The authors thank New Energy and Industrial Technology Development Organization (NEDO) under Ministry of Economy, Trade, and Industry (METI), Japan, for the financial support.

1. Préparation de PDMS Timbres <ol><li> Définir un moule de nanotrou (cyclo nanoimprinted film plastique de polymère d&#39;oléfine, taille: 50 mm x 50 mm) dans un polytétrafluoroéthylène (PTFE) conteneur. </li><li> Peser copolymère vinylméthylsiloxane-diméthylsiloxane (0,76 g pour le mm moule 50 mm × 50) dans une bouteille en verre jetable et le mélanger avec le complexe Pt-divinyltétraméthyldisiloxane (6 pi, en utilisant une micro pipette numérique avec une pointe de polypropylène à usage unique) et 2,4, 6,8-tetramethyltetra-vinylcyclotetrasiloxane (24 pi, en utilisant une micro pipette numérique avec une pointe de polypropylène à usage unique). </li><li> Ajouter copolymère méthylhydrosiloxane-diméthylsiloxane (0,24 ml, en utilisant une micro pipette numérique avec une pointe de polypropylène à usage unique) dans la bouteille en verre et mélanger rapidement à l&#39;aide d&#39;une pipette de verre jetable. Après que la surface du moule mis dans le récipient de PTFE est soufflé par N 2, versez le mélange résultant (&quot;dur&quot; PDMS de prépolymère) sur le moule et commencer spin-manteaution à 1000 tours par minute pendant 40 secondes pour atteindre l&#39;épaisseur de couche de 40 um ~. </li><li> Placer l&#39;échantillon de spin-enduit dans une chambre chaude préchauffé à 65 ° C pendant 30 min à brièvement réticuler les PDMS durs. </li><li> Pendant le chauffage, peser silicone (6 g) et de le mélanger avec du catalyseur (0,6 g) dans un flacon en verre à usage unique. Placer le flacon de verre dans un dessiccateur à vide et appliquer le vide (~ 133 Pa) pendant 15 minutes pour éliminer l&#39;air emprisonné dans le mélange de silicone (&quot;soft&quot; de prépolymère PDMS). </li><li> Sortez le moule et doux prépolymère de PDMS de la chambre de chauffage et dessiccateur à vide, respectivement, et verser rapidement les PDMS douces prépolymère sur le moule chauffé. L&#39;épaisseur de la couche de PDMS douce est d&#39;environ 3 mm. </li><li> Placer l&#39;échantillon résultant dans le dessiccateur à vide supplémentaire pour le dégazage supplémentaire à ~ 133 Pa au moins pendant 1 heure. </li><li> Transférer l&#39;échantillon dégazé à la chambre de chauffage et de commencer à chauffer progressivement jusqu&#39;à 80 ° C (vitesse de chauffage ~ 3 ° C / min). Gardez cette température pendant 5 heurespour réticuler les PDMS durs et mous complètement. </li><li> Après refroidissement de l&#39;échantillon jusqu&#39;à RT, décoller le timbre PDMS soigneusement du moule. Réutiliser le moule de préparer le second (ou plusieurs) des timbres, si nécessaire. Remarque: le même moule peut être utilisé au moins cinq fois sans dégradation de la qualité de cachet. </li><li> Couper le timbre nanopilier résultant (double couche dur / mou PDMS composite) 27 en morceaux de tailles désirées (typiquement 7 mm x 7 mm pour nos cellules solaires) à l&#39;aide d&#39;un couteau et de les stocker sous air jusqu&#39;à utilisation. </li></ol> 2. Préparation de copolymère bloc Solutions <ol><li> Peser la poudre du bloc polystyrène poly-2-vinylpyridine (PS- b -P2VP) dans une bouteille en verre et le mélanger avec o-xylène dans le rapport de 3 mg / ml (PS- b -P2VP / o-xylène) . </li><li> Incorporer le mélange à l&#39;aide d&#39;une barre d&#39;agitation magnétique revêtu de PTFE à 70 ° C pendant 1 heure. </li><li> Gardez la solution résultante pendant plus de 24 h à température ambiante, sans agitationanneau pour compléter la formation de micelles auto-assemblées. Sceller hermétiquement la solution et de le stocker dans des conditions ambiantes. Remarque: La qualité de la solution est inchangée, même un an après la préparation. </li></ol> 3. Préparation de μ c-Si: H Substrats <ol><li> Lavez les verres recouverts de SnO 2: F (désigner verre / SnO 2: F, ci-après) avec H 2 O (500 ml), du détergent (500 ml), et H 2 O (500 ml) à la température ambiante en utilisant un bain à ultrasons (15 min pour chaque). Séchez-les en soufflant N 2. </li><li> Chargez le verre nettoyée / SnO 2: F substrats dans un support de substrat et le dépôt de ZnO: Ga (20 nm) en utilisant un (DC) système de pulvérisation à courant continu avec les conditions spécifiées dans le tableau 2. </li><li> Chargez le verre / SnO 2: F / ZnO: substrats Ga dans un autre support de substrat et le dépôt μ c-Si: H p (10 nm), i (500 nm) et N (40 nm) couches en utilisant un produit chimique de plasma vapodépôt de r du système (PECVD) avec les conditions spécifiées dans le tableau 2. </li><li> Rangez la résultante μ c-Si: H (verre / SnO 2: F / ZnO: Ga / μ c-Si: H p - i - n) substrats sous vide ou N 2 jusqu&#39;à l&#39;étape de transfert de l&#39;impression. </li></ol> 4. Ag-revêtement de PDMS Timbres <ol><li> Laver les timbres (PDMS préparés à l&#39;étape 1) avec de l&#39;EtOH (30 ml) en utilisant un bain à ultrasons pendant 15 min et sèches par insufflation de N 2. </li><li> Chargez les timbres de PDMS nettoyées sur un support d&#39;échantillon en utilisant du ruban adhésif double-face et de déposer un film d&#39;Ag (10-80 nm) en utilisant un faisceau d&#39;électrons (EB) du système d&#39;évaporation avec les conditions suivantes: Taux dépôt = 5-10 Å / s, pression = ~ 1,5 x 10 -4 Pa. </li><li> Sortez les timbres Ag revêtus du système d&#39;évaporation EB et les utiliser immédiatement dans l&#39;étape d&#39;impression par transfert suivant. </li></ol> Impression 5. Transfert de Ag nanodisques sur mincefilm de Si Surfaces <ol><li> Sortez le mince film de Si substrats stocké sous vide ou N 2 et de spin-manteau avec la solution PS- b -P2VP (0,3 ml pour 50 mm × 50 mm échantillon, en utilisant un micro pipette numérique avec une pointe de polypropylène jetables) à 5000 tours par minute pendant 40 secondes. </li><li> Mouiller la surface PS- b -P2VP revêtu avec EtOH l&#39;aide d&#39;un micro pipette numérique (5 pm / de surface de la cellule) et d&#39;appliquer les PDMS Ag revêtus timbre doucement à la surface de EtOH-humide. Ne pas appuyer sur le timbre. </li><li> Placez le substrat Si couche mince avec le timbre dans une chambre à vide et appliquer le vide (~ 133 Pa). </li><li> Après 5 min, remplir la chambre à vide d&#39;air et sortir le substrat Si couche mince. </li><li> Enlevez le tampon du substrat Si couche mince en tenant à la fois du côté du timbre avec des pincettes pour transférer-impression nanodisques AG. Remarque: En cas de succès, la trace de marquage est visible comme une tache verdâtre. </li><li> Rincer le film mince substrat en Si de transfert imprimé avec un flux continu de EtOH pendant 15 s (~ 30 ml) et séché par soufflage de N2. </li><li> Retirer le revêtement PS-b-P2VP l&#39;aide d&#39;un système de plasma Ar. <ol><li> Placer la couche mince de Si substrat de transfert imprimé dans la chambre de processus du système de plasma Ar. </li><li> Pomper l&#39;air dans la chambre de traitement pendant environ 5 min (~ 20 pression Pa). </li><li> Ouvrez le robinet d&#39;une conduite de gaz Ar et ajuster manuellement le taux à 4 sccm. Attendre pour ~ 5 min pour stabiliser la pression à 40 Pa. </li><li> Générer Ar plasma pour 108 sec. </li><li> Fermez la vanne de la conduite de gaz Ar, arrêter le pompage, et remplir l&#39;air dans la chambre de traitement à prendre, les couches minces de transfert imprimé Si substrats plasmatiques nettoyés. </li></ol></li></ol> 6. Achèvement de Thin-film cellulaire Si solaire Fabrication <ol><li> Attacher des masques métalliques pour la couche mince de transfert des substrats de Si-imprimé après le traitement au plasma Ar utilisant des bandes de polyimide. </li><li> Charger les substrats masqués dans un support de substrat d&#39;un système de pulvérisation cathodique à courant continu et dépot ZnO: Ga (100 nm), Ag (250 nm), et de ZnO: Ga (40 nm) séquentiellement avec les conditions spécifiées dans le tableau 2. </li><li> Détachez les masques métalliques de substrats et enlever les couches masqués couche mince de silicium (par exemple, la zone où ZnO: Ga et Ag ne sont pas déposés) en utilisant un système de gravure ionique réactive (RIE). <ol><li> Placer les échantillons dans la chambre de traitement du système de RIE. </li><li> Pomper l&#39;air dans la chambre de traitement suivant les instructions du fabricant. </li><li> Définir les conditions du procédé de la façon suivante en suivant les instructions du fabricant: SF 6 / O 2 du débit = 100/20 sccm, la pression = 20 Pa, la puissance de 100 W, le temps = 1 min 20 sec. </li><li> Ouvrez les lignes SF 6 et O 2 gaz, stabiliser la pression, et générer un plasma. </li><li> Fermez la vanne de la ligne SF 6 et gaz O 2, arrêter le pompage, et remplissez N 2 dans la chambre de traitement de prendre les échantillons. </li></ol></li><li> Mettez leéchantillons dans une chambre sous vide recuit et commencer à chauffer progressivement jusqu&#39;à 175 ° C sous vide (~ 133 Pa). Gardez cette température pendant 2 heures, puis laisser refroidir à température ambiante. Remplissez air dans la chambre et de prendre des échantillons, qui peuvent désormais être appelées cellules. </li><li> Alliage à base de Sn-Zn à souder sur l&#39;électrode transparente avant (verre / SnO 2: F / ZnO: Ga, la partie exposée par le traitement RIE) en utilisant un dispositif de soudage par ultrasons. </li></ol> 7. Mesure de l&#39;efficacité quantique externe (EEQ) <ol><li> Fixez un masque protecteur de la lumière à une cellule fabriquée en utilisant du ruban de polyimide et définir la cellule masquée dans un support de cellule. Connectez sondes à l&#39;électrode avant soudé (+) et le dos Ag / ZnO: Ga électrode (-). </li><li> Mesurer spectres EEQ en utilisant un système de mesure de EEQ en suivant les instructions du fabricant avec une gamme de longueur d&#39;onde et étape de 300-1,100 nm et 5 nm, respectivement. </li></ol> 8. Mesure de photovoltaïque courant-tension (JV) Caractèretiques <ol><li> Calibrer l&#39;intensité lumineuse d&#39;un système de mesure des caractéristiques JV en utilisant une cellule de référence Si amorphe. <ol><li> Régler la cellule de référence Si amorphe à un support de cellule du système de mesure des caractéristiques JV, et illuminer la lumière. </li><li> Lisez le courant photogénéré l&#39;aide d&#39;un multimètre numérique équipé dans le système de mesure des caractéristiques JV. Ajuster l&#39;intensité lumineuse jusqu&#39;à ce que le courant photogénéré montre la bonne valeur pour la cellule de référence (8,34 mA / cm 2). </li></ol></li><li> Fixez un masque protecteur de la lumière à une cellule et définir la cellule masquée dans un support de cellule. Connectez sondes à l&#39;électrode avant soudé (+) et le dos Ag / ZnO: Ga électrode (-). </li><li> Illuminez la lumière calibrée (100 mW / cm 2, 1 soleil) sur la cellule et mesurer les courants photogénérées utilisant le système de mesure des caractéristiques JV suivant les instructions du fabricant avec un échelon de tension de 0,02 V. </li></ol>

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The authors have nothing to disclose.

Dans cet article, un double-couche disque / PDMS doux composite a été utilisé comme matériaux de timbre. 27 Cette combinaison a été jugée essentielle pour reproduire précisément la nanostructure de parent dans le moule, ce qui était un tableau à trous ronds hexagonale serrée dont le diamètre de 230 nm, profondeur de 500 nm, et l&#39;espacement des trous 460 nm de centre à centre. Lorsque seuls PDMS Soft a été utilisé, le timbre toujours abouti à une surface mal nanostructuré (par exemple, p...

Il ya eu une demande de longue date pour l&#39;application de nanostructures fonctionnelles dans un large éventail de domaines technologiques. Une des attentes de cette tendance est d&#39;ouvrir une nouvelle conception des architectures de dispositifs conduisant à des performances améliorées ou novatrices. Dans le domaine des cellules solaires, par exemple, l&#39;utilisation de nanostructures métalliques a été activement exploré en raison de leurs propriétés intrigantes optiques (c.-à-plasmoniques), 1 potentiellement bénéfique pour construire des systèmes efficaces de lumière de piégeage. 2,3 études En effet, certains théoriques 4 -6 ont suggéré qu&#39;une telle piégeage de lumière plasmonique pourrait avoir des effets qui dépassent les optiques de rayons classiques (de texturing) à base de limite de piégeage de la lumière. 7 En conséquence, l&#39;élaboration de stratégies pour intégrer les nanostructures métalliques désirés avec des cellules solaires est devenu de plus en plus importante pour réaliser ces prédictions théoriques. Un certain nombre de stratégies ontété proposées pour répondre à ce défi 8-24. Ceux-ci comprennent, par exemple, simple (low-cost) de recuit thermique de films métalliques ou 8,9 dispersion des nanoparticules métalliques pré-synthétisé, 10,11 qui tous deux ont abouti à des démonstrations réussies plasmonique piégeage de la lumière. Cependant, il convient de souligner que les nanostructures métalliques fabriqués par ces approches sont généralement difficiles à correspondre aux modèles théoriques. En revanche, les techniques de nanofabrication traditionnels dans les industries de semi-conducteurs, tels que la photolithographie et faisceau d&#39;électrons lithographie, 12,13 peuvent contrôler des structures bien en dessous du niveau de nm sous-100, mais ils sont souvent trop coûteux et fastidieux à appliquer aux cellules solaires, où la capacité de grande surface à faible coût est essentielle. Afin de remplir le faible coût, à haut débit, et les exigences de grande surface avec l&#39;échelle nanométrique contrôlabilité, des méthodes telles que la lithographie par nano, 14-16 lithographie douce, 17,18 </sup&gt; Nanosphères lithographie, 19-21 et le trou-masque lithographie colloïdale 22-24 serait prometteur. Parmi ces choix, nous avons développé une lithographie douce, technique avancée d&#39;impression par transfert. 25 L&#39;utilisation d&#39;un poly nanostructuré (diméthylsiloxane) (PDMS) timbres et des couches adhésives à base de copolymère bloc, motif de nanostructures métalliques commandés pourrait être facilement atteint sur ​​un certain nombre de technologies de les documents pertinents, y compris ceux pour les cellules solaires. L&#39;objectif de cet article est de décrire la procédure détaillée de notre approche de transfert d&#39;impression à intégrer la lumière piégeage nanostructures plasmoniques efficaces dans les structures de cellules solaires existantes. Comme un cas démonstratif, nanodisques AG et à couche mince hydrogénées microcristalline Si (uC-Si: H) des cellules solaires ont été sélectionnés dans cette étude (Figure 1), 26 bien que d&#39;autres types de métaux et les cellules solaires sont compatibles avec cette approche. Avec son processusla simplicité, l&#39;approche serait d&#39;intérêt pour divers chercheurs comme un outil pratique pour intégrer les nanostructures métalliques fonctionnelles avec des appareils.

<table border="0" cellpadding="0" cellspacing="0" style="width:864px;" width="863">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Nanohole mold</td>
			<td style="width:200px;">Scivax 
			http://www.scivax.com</td>
			<td style="width:129px;">FLH230/500-120</td>
			<td style="width:319px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">PTFE container</td>
			<td style="width:200px;">Eishin 
			http://www.colbyeishin.com</td>
			<td style="width:129px;">n/a</td>
			<td style="width:319px;">Custom made</td>
		</tr>
		<tr height="21">
			<td height="63" rowspan="3" style="height:63px;width:216px;">Hard-PDMS materials</td>
			<td rowspan="3" style="width:200px;">Gelest 
			http://www.gelest.com/gelest/forms/Home/home.aspx</td>
			<td style="width:129px;">VDT-731</td>
			<td>Vinylmethylsiloxane-dimethylsiloxane copolymer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:129px;">SIP6831.1</td>
			<td>Pt-divinyltetramethyldisiloxane complex</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:129px;">HMS-301</td>
			<td>Methylhydrosiloxane-dimethylsiloxane copolymer</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">2,4,6,8-tetramethyltetra-vinylcyclotetrasiloxane</td>
			<td style="width:200px;">Sigma-Aldrich 
			http://www.sigmaaldrich.com</td>
			<td style="width:129px;">396281</td>
			<td>Additive for hard-PDMS</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Soft-PDMS materials</td>
			<td style="width:200px;">Dow Corning 
			http://www.dowcorning.com</td>
			<td style="width:129px;">Sylgard-184</td>
			<td>Silicone precursor</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">PS-b-P2VP</td>
			<td style="width:200px;">Polymer Source 
			http://polymersource.com</td>
			<td style="width:129px;">P5742-S2VP</td>
			<td>Mn &#215; 103 = 133-b-132</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Glass/SnO2:F substrates</td>
			<td style="width:200px;">Asahi Glass Co. Ltd. 
			http://www.agc.com/english/company</td>
			<td style="width:129px;">Type VU</td>
			<td style="width:319px;">Chemical mechanical polished by D-process Inc. (http://d-process.jp/index.html) to flatten the surfaces</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Detergent</td>
			<td style="width:200px;">Fruuchi Chemical Co. 
			http://www.furuchi.co.jp/eng/main.htm</td>
			<td style="width:129px;">Semico-clean 56</td>
			<td style="width:319px;">Used for the cleaning of Glass/SnO2:F substrates</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">ZnO:Ga supputtering target</td>
			<td style="width:200px;">AGC Ceramics Co. Ltd. 
			http://www.agcc.jp/2005/en/index.html</td>
			<td style="width:129px;">5.7GZO</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Ag supputtering target</td>
			<td style="width:200px;">Mitsubishi Materials Co. 
			http://www.mitsubishicarbide.com/mmc/en/index.html</td>
			<td style="width:129px;">4NAg</td>
			<td></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Double-sided adhesive tape</td>
			<td style="width:200px;">Nisshin EM Co. 
			http://nisshin-em.co.jp/information/carbontape.html</td>
			<td style="width:129px;">732</td>
			<td></td>
		</tr>
		<tr height="120">
			<td height="120" style="height:120px;width:216px;">Polyimide tape</td>
			<td style="width:200px;">Dupont 
			http://www.dupont.com/products-and-services/membranes-films/polyimide-films/brands/kapton-polyimide-film.html</td>
			<td style="width:129px;">Kapton 650S#25</td>
			<td></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Sn-Zn-based Solder</td>
			<td style="width:200px;">Kuroda Techno Co., Ltd. 
			http://www.kuroda-techno.com/english/index.html</td>
			<td style="width:129px;">Cerasolzer AL-200</td>
			<td></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Digital micro pipette</td>
			<td style="width:200px;">Nichiryo 
			http://www.nichiryo.co.jp/en/product/pipette/ex/index.html</td>
			<td style="width:129px;">00-NPX2-20 
			00-NPX2-200 
			00-NPX2-1000</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Heating chamber</td>
			<td style="width:200px;">Tokyo Rikakikai Co., Ltd. 
			http://www.eyelaworld.com/product_view.php?id=120</td>
			<td style="width:129px;">VOS-201SD</td>
			<td></td>
		</tr>
		<tr height="84">
			<td height="126" rowspan="2" style="height:126px;width:216px;">Electron beam evaporator 
			(two types)</td>
			<td style="width:200px;">Canon-Anelva 
			https://www.canon-anelva.co.jp/english/index.html</td>
			<td style="width:129px;">n/a</td>
			<td style="width:319px;">Custom made</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:200px;">Arios 
			http://arios.com/</td>
			<td style="width:129px;">n/a</td>
			<td>Custom made</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Sputtering system</td>
			<td style="width:200px;">Ulvac 
			http://www.ulvac.co.jp/en</td>
			<td style="width:129px;">SBR-2306</td>
			<td style="width:319px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">PECVD system&#160;</td>
			<td style="width:200px;">Shimadzu Emit Co. Ltd. 
			http://www.shimadzu.co.jp/emit/en/</td>
			<td style="width:129px;">SLCM-13</td>
			<td style="width:319px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Ar plasma system&#160;</td>
			<td style="width:200px;">Diner Electric Gmbh 
			http://www.plasma.de/index.html</td>
			<td style="width:129px;">Femto&#160;</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">RIE system</td>
			<td style="width:200px;">Samco Inc. 
			http://www.samcointl.com</td>
			<td style="width:129px;">RIE-10NR</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Ultrasonic soldering device</td>
			<td style="width:200px;">Colby-Eishin Enterprises, Inc. 
			http://www.colbyeishin.com/sub_sunbonder.htm</td>
			<td style="width:129px;">SUNBONDER</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">EQE measurement system</td>
			<td rowspan="3" style="width:200px;">Bunkoukeiki Co. Ltd. 
			http://www.bunkoukeiki.co.jp/</td>
			<td style="width:129px;">CEP-25BXS</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">J-V characteristics measurement system</td>
			<td style="width:129px;">OTENTOSUN-5S-I/V</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Amorphous Si reference cell</td>
			<td style="width:129px;">WPVS-NPB-S1</td>
			<td>For light intensity calibration</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Digital multi-meter</td>
			<td style="width:200px;">Keithley Instruments Inc. 
			http://www.keithley.com/</td>
			<td style="width:129px;">2400</td>
			<td></td>
		</tr>
	</tbody>
</table>

integration of light trapping silver nanostructures in hydrogenated microcrystalline silicon solar cells by transfer printing

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly known as plasmonic effects, play an important role. Research in this field has, however, been impeded owing to the difficulty of fabricating devices containing the desired functional metal nanostructures. In order to provide a viable strategy to this issue, we herein show a transfer printing-based approach that allows the quick and low-cost integration of designed metal nanostructures with a variety of device architectures, including solar cells. Nanopillar poly(dimethylsiloxane) (PDMS) stamps were fabricated from a commercially available nanohole plastic film as a master mold. On this nanopatterned PDMS stamps, Ag films were deposited, which were then transfer-printed onto block copolymer (binding layer)-coated hydrogenated microcrystalline Si (&#181;c-Si:H) surface to afford ordered Ag nanodisk structures. It was confirmed that the resulting Ag nanodisk-incorporated &#181;c-Si:H solar cells show higher performances compared to a cell without the transfer-printed Ag nanodisks, thanks to plasmonic light trapping effect derived from the Ag nanodisks. Because of the simplicity and versatility, further device application would also be feasible thorough this approach.

La figure 2 illustre le processus général de l&#39;impression par transfert de nanodisques Ag sur la surface de uC-Si: H (n couche). En bref, un film d&#39;Ag (épaisseur: 10 à 80 nm) est d&#39;abord déposée sur la surface d&#39;un timbre nanopilier de PDMS par évaporation sous faisceau d&#39;électrons. En parallèle, une solution de -P2VP b de PS est déposée par centrifugation sur la surface d&#39;un fraîchement préparée uC-Si: H n couche. Par la suite, une goutte...

Watch this Scientific Journal Video about Integration of Light Trapping Silver Nanostructures in Hydrogenated Microcrystalline Silicon Solar Cells by Transfer Printing at JoVE.com

Integration of Light Trapping Silver Nanostructures in Hydrogenated Microcrystalline Silicon Solar Cells by Transfer Printing

A viable transfer printing-based methodology to introduce plasmonic metal nanostructures in solar cells is described. Using nanopillar poly(dimethylsiloxane) stamps, an Ag-based ordered nanodisk array was integrated with standard hydrogenated microcrystalline Si solar cells, which led to improved device performances due to plasmonic light trapping.

Intégration de la Lumière de piégeage argent Nanostructures dans hydrogénée microcristalline cellules solaires en silicium par impression par transfert

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly ...

integration-light-trapping-silver-nanostructures-hydrogenated

Research

JoVE Journal

Engineering

7.7K vues.  National Institute of Advanced Industrial Science and Technology, Koriyama, Fukushima, Japan. A viable transfer printing-based methodology to introduce plasmonic metal nanostructures in solar cells is described. Using nanopillar poly(dimethylsiloxane) stamps, an Ag-based ordered nanodisk array was integrated with standard hydrogenated microcrystalline Si solar cells, which led to improved device performances due to plasmonic light trapping.

Vidéo: Integration of Light Trapping Silver Nanostructures in Hydrogenated Microcrystalline Silicon Solar Cells by Transfer Printing

Polycrystalline Silicon Thin-film Solar cells with Plasmonic-enhanced Light-trapping

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To compensate for lower light absorption such physically thin devices have to incorporate light-trapping which increases their optical thickness. Light scattering by textured surfaces is a common technique but it cannot be universally applied to all solar cell technologies. Some cells, for example those made of evaporated silicon, are planar as produced and they require an alternative light-trapping means suitable for planar devices. Metal nanoparticles formed on planar silicon cell surface and capable of light scattering due to surface plasmon resonance is an effective approach.
The paper presents a fabrication procedure of evaporated polycrystalline silicon solar cells with plasmonic light-trapping and demonstrates how the cell quantum efficiency improves due to presence of metal nanoparticles.
To fabricate the cells a film consisting of alternative boron and phosphorous doped silicon layers is deposited on glass substrate by electron beam evaporation. An Initially amorphous film is crystallised and electronic defects are mitigated by annealing and hydrogen passivation. Metal grid contacts are applied to the layers of opposite polarity to extract electricity generated by the cell. Typically, such a ~2 &mu;m thick cell has a short-circuit current density (Jsc) of 14-16 mA/cm2, which can be increased up to 17-18 mA/cm2 (~25% higher) after application of a simple diffuse back reflector made of a white paint.
To implement plasmonic light-trapping a silver nanoparticle array is formed on the metallised cell silicon surface. A precursor silver film is deposited on the cell by thermal evaporation and annealed at 23&deg;C to form silver nanoparticles. Nanoparticle size and coverage, which affect plasmonic light-scattering, can be tuned for enhanced cell performance by varying the precursor film thickness and its annealing conditions. An optimised nanoparticle array alone results in cell Jsc enhancement of about 28%, similar to the effect of the diffuse reflector. The photocurrent can be further increased by coating the nanoparticles by a low refractive index dielectric, like MgF2, and applying the diffused reflector. The complete plasmonic cell structure comprises the polycrystalline silicon film, a silver nanoparticle array, a layer of MgF2, and a diffuse reflector. The Jsc for such cell is 21-23 mA/cm2, up to 45% higher than Jsc of the original cell without light-trapping or ~25% higher than Jsc for the cell with the diffuse reflector only.
Introduction
Light-trapping in silicon solar cells is commonly achieved via light scattering at textured interfaces. Scattered light travels through a cell at oblique angles for a longer distance and when such angles exceed the critical angle at the cell interfaces the light is permanently trapped in the cell by total internal reflection (Animation 1: Light-trapping). Although this scheme works well for most solar cells, there are developing technologies where ultra-thin Si layers are produced planar (e.g. layer-transfer technologies and epitaxial c-Si layers) 1 and or when such layers are not compatible with textures substrates (e.g. evaporated silicon) 2. For such originally planar Si layer alternative light trapping approaches, such as diffuse white paint reflector 3, silicon plasma texturing 4 or high refractive index nanoparticle reflector 5 have been suggested.
Metal nanoparticles can effectively scatter incident light into a higher refractive index material, like silicon, due to the surface plasmon resonance effect 6. They also can be easily formed on the planar silicon cell surface thus offering a light-trapping approach alternative to texturing. For a nanoparticle located at the air-silicon interface the scattered light fraction coupled into silicon exceeds 95% and a large faction of that light is scattered at angles above critical providing nearly ideal light-trapping condition (Animation 2: Plasmons on NP). The resonance can be tuned to the wavelength region, which is most important for a particular cell material and design, by varying the nanoparticle average size, surface coverage and local dielectric environment 6,7. Theoretical design principles of plasmonic nanoparticle solar cells have been suggested 8. In practice, Ag nanoparticle array is an ideal light-trapping partner for poly-Si thin-film solar cells because most of these design principle are naturally met. The simplest way of forming nanoparticles by thermal annealing of a thin precursor Ag film results in a random array with a relatively wide size and shape distribution, which is particularly suitable for light-trapping because such an array has a wide resonance peak, covering the wavelength range of 700-900 nm, important for poly-Si solar cell performance. The nanoparticle array can only be located on the rear poly-Si cell surface thus avoiding destructive interference between incident and scattered light which occurs for front-located nanoparticles 9. Moreover, poly-Si thin-film cells do not requires a passivating layer and the flat base-shaped nanoparticles (that naturally result from thermal annealing of a metal film) can be directly placed on silicon further increases plasmonic scattering efficiency due to surface plasmon-polariton resonance 10.
The cell with the plasmonic nanoparticle array as described above can have a photocurrent about 28% higher than the original cell. However, the array still transmits a significant amount of light which escapes through the rear of the cell and does not contribute into the current. This loss can be mitigated by adding a rear reflector to allow catching transmitted light and re-directing it back to the cell. Providing sufficient distance between the reflector and the nanoparticles (a few hundred nanometers) the reflected light will then experience one more plasmonic scattering event while passing through the nanoparticle array on re-entering the cell and the reflector itself can be made diffuse - both effects further facilitating light scattering and hence light-trapping. Importantly, the Ag nanoparticles have to be encapsulated with an inert and low refractive index dielectric, like MgF2 or SiO2, from the rear reflector to avoid mechanical and chemical damage 7. Low refractive index for this cladding layer is required to maintain a high coupling fraction into silicon and larger scattering angles, which are ensured by the high optical contrast between the media on both sides of the nanoparticle, silicon and dielectric 6. The photocurrent of the plasmonic cell with the diffuse rear reflector can be up to 45% higher than the current of the original cell or up to 25% higher than the current of an equivalent cell with the diffuse reflector only.

Polycrystalline silicon thin-film solar cells on glass are fabricated by deposition of boron and phosphorous doped silicon layers followed by crystallisation, defect passivation and metallisation. Plasmonic light-trapping is introduced by forming Ag nanoparticles on the silicon cell surface capped with a diffused reflector resulting in ~45% photocurrent enhancement.

Base de silicium polycristallin à couche mince des cellules solaires avec plasmonique amélioré par Light-piégeage

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To ...

Recherche

Ingénierie

A Method to Fabricate Disconnected Silver Nanostructures in 3D

The standard nanofabrication toolkit includes techniques primarily aimed at creating 2D patterns in dielectric media. Creating metal patterns on a submicron scale requires a combination of nanofabrication tools and several material processing steps. For example, steps to create planar metal structures using ultraviolet photolithography and electron-beam lithography can include sample exposure, sample development, metal deposition, and metal liftoff. To create 3D metal structures, the sequence is repeated multiple times. The complexity and difficulty of stacking and aligning multiple layers limits practical implementations of 3D metal structuring using standard nanofabrication tools. Femtosecond-laser direct-writing has emerged as a pre-eminent technique for 3D nanofabrication.1,2 Femtosecond lasers are frequently used to create 3D patterns in polymers and glasses.3-7 However, 3D metal direct-writing remains a challenge. Here, we describe a method to fabricate silver nanostructures embedded inside a polymer matrix using a femtosecond laser centered at 800 nm. The method enables the fabrication of patterns not feasible using other techniques, such as 3D arrays of disconnected silver voxels.8 Disconnected 3D metal patterns are useful for metamaterials where unit cells are not in contact with each other,9 such as coupled metal dot10,11or coupled metal rod12,13 resonators. Potential applications include negative index metamaterials, invisibility cloaks, and perfect lenses.
In femtosecond-laser direct-writing, the laser wavelength is chosen such that photons are not linearly absorbed in the target medium. When the laser pulse duration is compressed to the femtosecond time scale and the radiation is tightly focused inside the target, the extremely high intensity induces nonlinear absorption. Multiple photons are absorbed simultaneously to cause electronic transitions that lead to material modification within the focused region. Using this approach, one can form structures in the bulk of a material rather than on its surface.
Most work on 3D direct metal writing has focused on creating self-supported metal structures.14-16 The method described here yields sub-micrometer silver structures that do not need to be self-supported because they are embedded inside a matrix. A doped polymer matrix is prepared using a mixture of silver nitrate (AgNO3), polyvinylpyrrolidone (PVP) and water (H2O). Samples are then patterned by irradiation with an 11-MHz femtosecond laser producing 50-fs pulses. During irradiation, photoreduction of silver ions is induced through nonlinear absorption, creating an aggregate of silver nanoparticles in the focal region. Using this approach we create silver patterns embedded in a doped PVP matrix. Adding 3D translation of the sample extends the patterning to three dimensions.

Femtosecond-laser direct-writing is frequently used to create three-dimensional (3D) patterns in polymers and glasses. However, patterning metals in 3D remains a challenge. We describe a method for fabricating silver nanostructures embedded inside a polymer matrix using a femtosecond laser centered at 800 nm.

Une méthode pour fabriquer des nanostructures d&#39;argent déconnectés en 3D

The standard nanofabrication toolkit includes  techniques primarily aimed at creating 2D patterns in dielectric media. Creating  metal patterns on a ...

Making Record-efficiency SnS Solar Cells by Thermal Evaporation and Atomic Layer Deposition

Tin sulfide (SnS) is a candidate absorber material for Earth-abundant, non-toxic solar cells. SnS offers easy phase control and rapid growth by congruent thermal evaporation, and it absorbs visible light strongly. However, for a long time the record power conversion efficiency of SnS solar cells remained below 2%. Recently we demonstrated new certified record efficiencies of 4.36% using SnS deposited by atomic layer deposition, and 3.88% using thermal evaporation. Here the fabrication procedure for these record solar cells is described, and the statistical distribution of the fabrication process is reported. The standard deviation of efficiency measured on a single substrate is typically over 0.5%. All steps including substrate selection and cleaning, Mo sputtering for the rear contact (cathode), SnS deposition, annealing, surface passivation, Zn(O,S) buffer layer selection and deposition, transparent conductor (anode) deposition, and metallization are described. On each substrate we fabricate 11 individual devices, each with active area 0.25 cm2. Further, a system for high throughput measurements of current-voltage curves under simulated solar light, and external quantum efficiency measurement with variable light bias is described. With this system we are able to measure full data sets on all 11 devices in an automated manner and in minimal time. These results illustrate the value of studying large sample sets, rather than focusing narrowly on the highest performing devices. Large data sets help us to distinguish and remedy individual loss mechanisms affecting our devices.

Tin sulfide (SnS) is a candidate material for Earth-abundant, non-toxic solar cells. Here, we demonstrate the fabrication procedure of the SnS solar cells employing atomic layer deposition, which yields 4.36% certified power conversion efficiency, and thermal evaporation which yields 3.88%.

Faire Enregistrez-efficacité SnS cellules solaires par évaporation thermique et Atomic Layer Deposition

Tin sulfide (SnS) is a candidate absorber material for Earth-abundant, non-toxic solar cells. SnS offers easy phase control and rapid growth by congruent ...

Selective Area Modification of Silicon Surface Wettability by Pulsed UV Laser Irradiation in Liquid Environment

The wettability of silicon (Si) is one of the important parameters in the technology of surface functionalization of this material and fabrication of biosensing devices. We report on a protocol of using KrF and ArF lasers irradiating Si (001) samples immersed in a liquid environment with low number of pulses and operating at moderately low pulse fluences to induce Si wettability modification. Wafers immersed for up to 4 hr in a 0.01% H2O2/H2O solution did not show measurable change in their initial contact angle (CA) ~75&#176;. However, the 500-pulse KrF and ArF lasers irradiation of such wafers in a microchamber filled with 0.01% H2O2/H2O solution at 250 and 65 mJ/cm2, respectively, has decreased the CA to near 15&#176;, indicating the formation of a superhydrophilic surface. The formation of OH-terminated Si (001), with no measurable change of the wafer&#8217;s surface morphology, has been confirmed by X-ray photoelectron spectroscopy and atomic force microscopy measurements. The selective area irradiated samples were then immersed in a biotin-conjugated fluorescein-stained nanospheres solution for 2 hr, resulting in a successful immobilization of the nanospheres in the non-irradiated area. This illustrates the potential of&#160;the method for selective area biofunctionalization and fabrication of advanced Si-based biosensing architectures. We also describe a similar protocol of irradiation of wafers immersed in methanol (CH3OH) using ArF laser operating at pulse fluence of 65 mJ/cm2 and in situ formation of a strongly hydrophobic surface of Si (001) with the CA of 103&#176;. The XPS results indicate ArF laser induced formation of Si&#8211;(OCH3)x compounds responsible for the observed hydrophobicity. However, no such compounds were found by XPS on the Si surface irradiated by KrF laser in methanol, demonstrating the inability of the KrF laser to photodissociate methanol and create -OCH3 radicals.

We report on a process of in situ alteration of HF treated Si (001) surface into a hydrophilic or hydrophobic state by irradiating samples in microfluidic chambers filled with&#160;H2O2/H2O solution (0.01%-0.5%) or methanol solutions using pulsed UV laser of a relative low pulse fluence.

Selective Area Modification de la Silicon mouillabilité de surface par irradiation laser pulsé UV en milieu liquide

The wettability of silicon (Si) is one of the important parameters in the technology of surface functionalization of this material and fabrication of ...

Light Enhanced Hydrofluoric Acid Passivation: A Sensitive Technique for Detecting Bulk Silicon Defects

A procedure to measure the bulk lifetime (&#62;100 &#181;sec) of silicon wafers by temporarily attaining a very high level of surface passivation when immersing the wafers in hydrofluoric acid (HF) is presented. By this procedure three critical steps are required to attain the bulk lifetime. Firstly, prior to immersing silicon wafers into HF, they are chemically cleaned and subsequently etched in 25% tetramethylammonium hydroxide. Secondly, the chemically treated wafers are then placed into a large plastic container filled with a mixture of HF and hydrochloric acid, and then centered over an inductive coil for photoconductance (PC) measurements. Thirdly, to inhibit surface recombination and measure the bulk lifetime, the wafers are illuminated at 0.2 suns for 1 min&#160;using a halogen lamp, the illumination is switched off, and a PC measurement is immediately taken. By this procedure, the characteristics of bulk silicon defects can be accurately determined. Furthermore, it is anticipated that a sensitive RT surface passivation technique will be imperative for examining bulk silicon defects when their concentration is low (&#60;1012 cm-3).

A RT liquid surface passivation technique to investigate the recombination activity of bulk silicon defects is described. For the technique to be successful, three critical steps are required: (i) chemical cleaning and etching of silicon, (ii) immersion of silicon in 15% hydrofluoric acid and (iii) illumination for 1 min.

Lumière amélioré la passivation de l&#39;acide fluorhydrique: une technique sensible pour détecter des défauts de silicium massif

A procedure to measure the bulk lifetime (&#62;100 &#181;sec) of silicon wafers by temporarily attaining a very high level of surface passivation when ...

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Here, we present a protocol to fabricate organic thin film solar cells using a mini-slot die coater and related in-line structure characterizations using synchrotron scattering techniques.

Fabrication d&#39;impression de gros hétérojonction cellules solaires et<em&gt; In Situ</em&gt; Morphologie Caractérisation

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices ...

Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 &#181;m thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm2 and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 &#176;C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 &#730;C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells.

This paper investigates the suitability of inkjet printing for the manufacturing of dye-sensitized solar cells. A binder-free TiO2 nanoparticle ink was formulated and printed onto a FTO glass substrate. The printed layer was fabricated into a cell with an active area of 0.25 cm2 and an efficiency of 3.5%.

Impression numérique de dioxyde de titane pour les cellules solaires à colorant

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less ...

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Here, we demonstrate the incorporation of monovalent cation additives into CH3NH3PbI3 perovskite in order to adjust the optical, excitonic, and electrical properties. The possibility of doping was investigated by adding monovalent cation halides with similar ionic radii to Pb2+, including Cu+, Na+, and Ag+. A shift in the Fermi level and a remarkable decrease of sub-bandgap optical absorption, along with a lower energetic disorder in the perovskite, was achieved. An order-of-magnitude enhancement in the bulk hole mobility and a significant reduction of transport activation energy within an additive-based perovskite device was attained. The confluence of the aforementioned improved properties in the presence of these cations led to an enhancement in the photovoltaic parameters of the perovskite solar cell. An increase of 70 mV in open circuit voltage for AgI and a 2 mA/cm2 improvement in photocurrent density for NaI- and CuBr-based solar cells were achieved compared to the pristine device. Our work paves the way for further improvements in the optoelectronic quality of CH3NH3PbI3 perovskite and subsequent devices. It highlights a new avenue for investigations on the role of dopant impurities in crystallization and controls the electronic defect density in perovskite structures.

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Here, we present a protocol to adjust the properties of solution-processed CH3NH3PbI3 through the incorporation of monovalent cation additives in order to achieve highly efficient perovskite solar cells.

Monovalents Cation dopage du CH<sub&gt; 3</sub&gt; NH<sub&gt; 3</sub&gt; PbI<sub&gt; 3</sub&gt; Pour Efficient cellules solaires perovskite

Here, we demonstrate the incorporation of monovalent cation additives into CH3NH3PbI3 perovskite in order to adjust the optical, excitonic, and electrical ...

Challenges in Rheological Characterization of Highly Concentrated Suspensions &#8212; A Case Study for Screen-printing Silver Pastes

A comprehensive rheological characterization of highly concentrated suspensions or pastes is mandatory for a targeted product development meeting the manifold requirements during processing and application of such complex fluids. In this investigation, measuring protocols for a conclusive assessment of different process relevant rheological parameters have been evaluated. This includes the determination of yield stress, viscosity, wall slip velocity, structural recovery after large deformation and elongation at break as well as tensile force during filament stretching.
The importance of concomitant video recordings during parallel-plate rotational rheometry for a significant determination of rheological quantities is demonstrated. The deformation profile and flow field at the sample edge can be determined using appropriate markers. Thus, measurement parameter settings and plate roughness values can be identified for which yield stress and viscosity measurements are possible. Slip velocity can be measured directly and measuring conditions at which plug flow, shear banding or sample spillover occur can be identified clearly. 
Video recordings further confirm that the change in shear moduli observed during three stage oscillatory shear tests with small deformation amplitude in stage I and III but large oscillation amplitude in stage II can be directly attributed to structural break down and recovery. For the pastes investigated here, the degree of irreversible, shear-induced structural change increases with increasing deformation amplitude in stage II until a saturation is reached at deformations corresponding to the crossover of G' and G'', but the irreversible damage is independent of the duration of large amplitude shear. 
A capillary breakup elongational rheometer and a tensile tester have been used to characterize deformation and breakup behavior of highly filled pastes in uniaxial elongation. Significant differences were observed in all experiments described above for two commercial screen-printing silver pastes used for front side metallization of Si-solar cells.

Challenges in Rheological Characterization of Highly Concentrated Suspensions &amp;#8212; A Case Study for Screen-printing Silver Pastes

A protocol for a robust and application relevant rheological characterization of highly concentrated suspensions is presented. Silver pastes used for screen-printing application in solar cell production are employed as model systems.

Défis à rhéologique Caractérisation des concentrés - Suspensions très Une étude de cas pour la sérigraphie argent Pastes

A comprehensive rheological characterization of highly concentrated suspensions or pastes is mandatory for a targeted product development meeting the ...

In Situ Monitoring of the Accelerated Performance Degradation of Solar Cells and Modules: A Case Study for Cu(In,Ga)Se2 Solar Cells

The levelized cost of electricity (LCOE) of photovoltaic (PV) systems is determined by, among other factors, the PV module reliability. Better prediction of degradation mechanisms and prevention of module field failure can consequently decrease investment risks as well as increase the electricity yield. An improved knowledge level can for these reasons significantly decrease the total costs of PV electricity. 
In order to better understand and minimize the degradation of PV modules, the occurring degradation mechanisms and conditions should be identified. This should preferably happen under combined stresses, since modules in the field are also simultaneously exposed to multiple stress factors. Therefore, two 'Combined Stress test with in situ measurement' setups have been designed and constructed. These setups allow the simultaneous use of humidity, temperature, illumination, and electrical biases as independently controlled stress factors on solar cells and minimodules. The setups also allow real-time monitoring of the electrical properties of these samples. This protocol presents these setups and describes the experimental possibilities. Moreover, results obtained with these setups are also presented: various examples about the influence of both deposition and degradation conditions on the stability of thin film Cu(In,Ga)Se2 (CIGS) as well as Cu2ZnSnSe4 (CZTS) solar cells are described. Results on the temperature dependency of CIGS solar cells are also presented.

In Situ Monitoring of the Accelerated Performance Degradation of Solar Cells and Modules: A Case Study for CuIn,GaSe2 Solar Cells

Two &#39;Combined Stress test with in situ measurement&#39; setups, which allow real-time monitoring of accelerated degradation of solar cells and modules, were designed and constructed. These setups allow the simultaneous use of humidity, temperature, electrical biases, and illumination as independently controlled stress factors. The setups and various experiments executed are presented.

In Situ Suivi de la dégradation de Performance accélérée des cellules et Modules solaires : une étude de cas pour les cellules solaires de Cu (In, Ga) Se2

The levelized cost of electricity (LCOE) of photovoltaic (PV) systems is determined by, among other factors, the PV module reliability. Better prediction ...