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. Preparazione di PDMS Francobolli <ol><li> Impostare uno stampo nanohole (ciclo nanoimprinted film plastico polimero olefinico, dimensioni: 50 mm x 50 mm) in un politetrafluoroetilene (PTFE) contenitore. </li><li> Pesare copolimero vinylmethylsiloxane-dimetilsiloxano (0,76 g per la muffa mm 50 mm × 50) in una bottiglia di vetro a perdere e mescolare con complesso di Pt-divinyltetramethyldisiloxane (6 microlitri, con una micro pipetta digitale con una punta in polipropilene monouso) e 2,4, 6,8-tetramethyltetra-vinylcyclotetrasiloxane (24 microlitri, con una micro pipetta digitale con una punta in polipropilene usa e getta). </li><li> Aggiungere copolimero methylhydrosiloxane-dimetilsiloxano (0,24 ml, con una micro pipetta digitale con una punta in polipropilene monouso) nella bottiglia di vetro e mescolare rapidamente utilizzando una pipetta di vetro usa e getta. Dopo la superficie dello stampo impostato nel contenitore PTFE viene soffiato da N 2, versare la miscela risultante (&quot;hard&quot; prepolimero PDMS) sullo stampo e iniziare spin-coating a 1.000 rpm per 40 secondi per ottenere lo spessore di ~ 40 micron. </li><li> Trasferire il campione spin-rivestito in una camera calda preriscaldato a 65 ° C per 30 min a brevemente reticolare il PDMS duri. </li><li> Durante il riscaldamento, pesare silicone (6 g) e mescolare con catalizzatore (0,6 g) in una bottiglia di vetro monouso. Posizionare la bottiglia di vetro in un essiccatore a vuoto, applicare il vuoto (~ 133 Pa) per 15 minuti per eliminare l&#39;aria intrappolata nella miscela silicone (&quot;soft&quot; prepolimero PDMS). </li><li> Estrarre lo stampo e morbido prepolimero PDMS dalla camera di riscaldamento e essiccatore a vuoto, rispettivamente, e versare rapidamente il PDMS morbide prepolimero sullo stampo riscaldato. Lo spessore dello strato morbido PDMS è ~ 3 mm. </li><li> Posizionare il campione con conseguente essiccatore a vuoto di nuovo per ulteriori degasaggio a ~ 133 Pa per almeno 1 ora. </li><li> Trasferire il campione degasato alla camera di riscaldamento e iniziare riscaldando gradualmente fino a 80 ° C (velocità di riscaldamento ~ 3 ° C / min). Mantenere questa temperatura per 5 oreper reticolare le PDMS duri e molli completamente. </li><li> Dopo il raffreddamento del campione fino a RT, staccare il PDMS bollo con attenzione dallo stampo. Riutilizzare lo stampo per preparare il secondo (o più) Stamp, se necessario. Nota: Lo stesso stampo può essere utilizzato almeno cinque volte senza degradazione della qualità timbro. </li><li> Tagliare il timbro nanopillar risultante (a doppio strato duro / morbido PDMS composito) 27 in pezzi di dimensioni desiderate (in genere 7 mm x 7 mm per le nostre cellule solari) utilizzando un coltello e memorizzarle sotto aria fino al momento dell&#39;uso. </li></ol> 2. Preparazione di Block copolimero Solutions <ol><li> Pesare la polvere di blocco polystyrene- -poly-2-vinilpiridina (PS b -P2VP) in una bottiglia di vetro e mescolare con o -xylene nel rapporto di 3 mg / ml (PS b -P2VP / o -xylene) . </li><li> Mescolare la miscela utilizzando un agitatore magnetico rivestito in PTFE a 70 ° C per 1 ora. </li><li> Mantenere la soluzione risultante per più di 24 ore a RT senza mescolareanello per completare la formazione di micelle autoassemblati. Strettamente sigillare la soluzione e memorizzarlo in condizioni ambientali. Nota: La qualità della soluzione è invariata anche un anno dopo la preparazione. </li></ol> 3. Preparazione del μ c-Si: H Substrati <ol><li> Occhiali Lavare coperti con SnO 2: F (denotare vetro / SnO 2: F, di seguito) con H 2 O (500 ml), detergente (500 ml) e H 2 O (500 ml) a temperatura ambiente utilizzando un bagno ad ultrasuoni (15 min per ciascuno). Asciugarli soffiando N 2. </li><li> Caricare il vetro pulito / SnO 2: substrati F in un supporto substrato e deposito ZnO: Ga (20 Nm) con una corrente del sistema sputtering continua (DC) con le condizioni specificate nella tabella 2. </li><li> Caricare il vetro / SnO 2: F / ZnO: substrati Ga in un altro titolare substrato e deposito μ c-Si: H p (10 nm), i (500 nm), e N (40 nm) livelli utilizzando una sostanza chimica al plasma-enhanced vapor deposizione sistema (PECVD) con le condizioni specificate nella tabella 2. </li><li> Conservare il conseguente μ c-Si: H (vetro / SnO 2: F / ZnO: Ga / μ c-Si: H p - i - n) substrati sotto vuoto o N 2 fino alla fase di trasferimento la stampa. </li></ol> 4. Ag-rivestimento di PDMS Francobolli <ol><li> Lavare i francobolli PDMS (previste al punto 1) con EtOH (30 ml) con un bagno a ultrasuoni per 15 minuti e secco che soffia da N 2. </li><li> Caricare i PDMS timbri puliti su un supporto campione utilizzando nastro biadesivo adesivo e depositare un film Ag (10-80 nm) utilizzando un fascio di elettroni (EB) sistema di evaporazione con le condizioni seguenti: velocità di deposizione = 5-10 / sec, pressione = ~ 1.5 × 10 -4 Pa. </li><li> Estrarre i francobolli Ag rivestite dal sistema di evaporazione EB e utilizzarli immediatamente nel passaggio seguente stampa transfer. </li></ol> 5. Trasferimento di stampa di Ag Nanodisks su Thin-pellicola Si Superfici <ol><li> Estrarre il film sottile Si memorizzati substrati sotto vuoto o N 2 e spin-coat con la soluzione PS b -P2VP (0,3 ml per 50 mm x 50 mm di esempio, usando un micro pipetta digitale con una punta polipropilene monouso) a 5.000 rpm per 40 sec. </li><li> Bagnare la superficie PS b -P2VP rivestite con EtOH utilizzando una micro pipetta digitale (5 micron / zona cellulare) e si applicano le PDMS Ag rivestite timbro dolcemente sulla superficie EtOH bagnato. Non premere il timbro. </li><li> Posizionare il film sottile substrato di Si con il timbro in una camera a vuoto, applicare il vuoto (~ 133 Pa). </li><li> Dopo 5 minuti, riempire la camera a vuoto con l&#39;aria ed estrarre il film sottile Si substrato. </li><li> Rimuovere il timbro dal film sottile Si substrato tenendo il lato sia del timbro con una pinzetta per trasferire-stampa nanodisks Ag. Nota: In caso di successo, la traccia di stampaggio è visibile come una macchia verdastra. </li><li> Risciacquare il film sottile substrato di Si transfer-stampata con un flusso continuo di EtOH per 15 sec (~ 30 ml) e insufflando N 2. </li><li> Rimuovere il rivestimento PS-b-P2VP utilizzando un sistema al plasma Ar. <ol><li> Posizionare il film sottile Si substrato trasferimento stampato nella camera di processo del sistema plasma Ar. </li><li> Scaricare l&#39;aria nella camera di processo per ~ 5 min (pressione ~ 20 Pa). </li><li> Aprire la valvola di una linea gas Ar e regolare manualmente la portata di 4 sccm. Attendere per ~ 5 minuti per stabilizzare la pressione di 40 Pa. </li><li> Genera Ar plasma per 108 secondi. </li><li> Chiudere la valvola della linea del gas Ar, interrompere il pompaggio, e riempire l&#39;aria nella camera di processo per eliminare i, trasferimento stampato a film sottile Si substrati plasma pulita. </li></ol></li></ol> 6. Completamento del film sottile Fabrication cellulare Si solare <ol><li> Fissare le maschere di metallo per la sottile pellicola di trasferimento stampato Si substrati dopo il trattamento al plasma Ar utilizzano nastri in poliammide. </li><li> Caricare i substrati mascherati in un supporto substrato di un sistema di sputtering DC e Deposit ZnO: Ga (100 nm), Ag (250 nm), e ZnO: Ga (40 nm) in sequenza le condizioni specificate nella tabella 2. </li><li> Staccare le maschere di metallo dai substrati e rimuovere i mascherati film sottile Si strati (cioè, l&#39;area dove ZnO: Ga e Ag non sono stati depositati) utilizzando un sistema di attacco con ioni reattivi (RIE). <ol><li> Porre i campioni nella camera di processo del sistema RIE. </li><li> Scaricare l&#39;aria nella camera di processo seguendo le istruzioni del produttore. </li><li> Impostare le condizioni di processo come segue seguendo le istruzioni del produttore: SF 6 / O 2 Portata = 100/20 SCCM, pressione = 20 Pa, 100 W di potenza, tempo = 1 min 20 sec. </li><li> Aprire le linee di SF 6 e O 2 gas, stabilizzare la pressione, e generare plasma. </li><li> Chiudere la valvola della linea SF 6 e O 2 gas, interrompere il pompaggio, e riempire N 2 nella camera di processo per estrarre i campioni. </li></ol></li><li> Metti ilcampioni in una camera a vuoto ricottura e cominciano riscaldare gradualmente fino a 175 ° C sotto vuoto (~ 133 Pa). Mantenere questa temperatura per 2 ore, e poi lasciare raffreddare a temperatura ambiente. Riempire d&#39;aria nella camera e prendere i campioni, che ora possono essere chiamati celle. </li><li> Lega a base di Zn-Sn-Saldare sull&#39;elettrodo anteriore trasparente (vetro / SnO 2: F / ZnO: Ga, la parte esposta dal trattamento RIE) usando un dispositivo di saldatura ad ultrasuoni. </li></ol> 7. Misura di efficienza quantica esterna (EQE) <ol><li> Allegare una maschera di luce-schermatura per una cella fabbricato con nastro poliimmide e impostare la cella mascherato in un supporto cella. Collegare sonde all&#39;elettrodo anteriore saldato (+) e ritorno Ag / ZnO: Ga elettrodo (-). </li><li> Misurare spettri EQE utilizzando un sistema di misurazione EQE seguendo le istruzioni del produttore con una gamma di lunghezze d&#39;onda e fase di 300-1,100 nm e 5 nm, rispettivamente. </li></ol> 8. Misura della Fotovoltaico Corrente-Tensione (JV) Personaggiostiche <ol><li> Calibrare l&#39;intensità luminosa di un sistema di misura caratteristiche JV utilizzando una cella di riferimento Si amorfo. <ol><li> Impostare la cella di riferimento Si amorfo ad un supporto cella del sistema di misurazione caratteristiche JV, e illuminare la luce. </li><li> Leggere la corrente fotogenerata utilizzando un multimetro digitale dotata del sistema di misura caratteristiche JV. Regolare l&#39;intensità della luce finché la corrente fotogenerata mostra il giusto valore per la cella di riferimento (8,34 mA / cm 2). </li></ol></li><li> Attaccare una maschera luce schermatura a una cella e impostare la cella mascherato in un supporto della cella. Collegare sonde all&#39;elettrodo anteriore saldato (+) e ritorno Ag / ZnO: Ga elettrodo (-). </li><li> Illuminare la luce calibrata (100 mW / cm 2, 1 sole) sulla cella e misurare correnti fotogenerati utilizzando il sistema di misurazione caratteristiche JV seguendo le istruzioni del produttore con un gradino di tensione di 0,02 V. </li></ol>

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The authors have nothing to disclose.

In questo articolo, un hard doppio strato / PDMS morbide composito è stato impiegato come materiale di bollo. 27 Questa combinazione è risultata essenziale per replicare esattamente la nanostruttura genitore nello stampo, che era una matrice rotonda buche esagonale vicino ricco di diametro di 230 nm, 500 nm di profondità, e foro centrale a centro spaziatura di 460 nm. Quando solo PDMS morbide è stato utilizzato, il timbro sempre comportato una superficie di poco nanostrutturati (per esempio, nessun spigol...

Vi è stata una richiesta di lunga data per l&#39;applicazione di nanostrutture funzionali in una vasta gamma di campo tecnologico. Una delle aspettative per questa tendenza è quello di aprire il nuovo disegno di architetture di dispositivi che portano a migliori prestazioni e innovativi. Nel campo delle celle solari, per esempio, l&#39;utilizzo di nanostrutture metalliche ha attivamente esplorata a causa delle loro proprietà interessanti (cioè, plasmoniche) ottici, 1 potenzialmente utile per costruire sistemi di cattura luce efficaci. 2,3 studi Infatti, alcuni teorici 4 -6 hanno suggerito che tale cattura luce plasmoniche potrebbe ottenere effetti che superano l&#39;ottica a raggi convenzionali (texturing) -based limite di cattura della luce. 7 Di conseguenza, lo sviluppo di strategie per integrare nanostrutture metalliche desiderati con celle solari è diventato sempre più importante per la realizzazione di questi previsioni teoriche. Un certo numero di strategie hannostato proposto per affrontare questa sfida. 8-24 Questi includono, per esempio, semplice (a basso costo) ricottura termica di film metallici 8,9 o dispersione di nanoparticelle metalliche pre-sintetizzato, 10,11 entrambi i quali hanno portato a manifestazioni di successo di cattura la luce plasmonica. Tuttavia, va sottolineato che le nanostrutture metallo da questi approcci sono solitamente difficili da corrispondere ai modelli teorici. Al contrario, le tecniche di nanofabbricazione tradizionali industrie semiconduttore come fotolitografia e litografia a fascio elettronico, 12,13 possono controllare strutture ben al di sotto del livello di sub-100 nm, ma sono spesso troppo costosi e richiede tempo per applicare alle celle solari, dove la capacità a basso costo grandi superfici è essenziale. Al fine di soddisfare il basso costo, high-throughput, e le esigenze di grande superficie con scala nanometrica controllabilità, metodi come nanoimprint la litografia, 14-16 morbido litografia, 17,18 </sup&gt; Nanosphere litografia, 19-21 e hole-maschera colloidale litografia 22-24 sarebbe promettente. Tra queste scelte, abbiamo sviluppato un litografica morbido, avanzata tecnica di stampa di trasferimento. 25 Uso un poli nanostrutturati (dimetilsilossano) (PDMS) francobolli e strati adesivi a base di copolimero a blocchi, patterning di nanostrutture metalliche ordinato potrebbe essere facilmente ottenuto su un certo numero di tecnologicamente materiali relativi, compresi quelli per le celle solari. Il focus di questo articolo è quello di descrivere la procedura dettagliata del nostro approccio stampa transfer per incorporare efficaci luce di cattura nanostrutture plasmoniche in strutture di celle solari esistenti. Come caso dimostrativo, nanodisks Ag e film sottile idrogenati microcristallina Si (uC-Si: H) celle solari sono stati selezionati in questo studio (Figura 1), 26 anche se altri tipi di metalli e celle solari sono compatibili con questo approccio. Insieme con il suo processosemplicità, l&#39;approccio sarebbe di interesse per diversi ricercatori come uno strumento utile per integrare nanostrutture metalliche funzionali con i dispositivi.

<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.

Figura 2 illustra la procedura generale per la stampa a trasferimento di nanodisks Ag sulla superficie uC-Si: H (n layer). Brevemente, un film Ag (spessore: 10-80 nm) viene dapprima depositato sulla superficie di un timbro nanopillar PDMS dal fascio di elettroni evaporazione. In parallelo, una soluzione -P2VP b PS è spin-rivestito sulla superficie di un preparato fresco uC-Si: H n strato. Successivamente, una gocciolina di EtOH è posto sulla superficie rivestita -P2VP PS <em...

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.

Integrazione di luce Trapping Argento Nanostrutture in silicio microcristallino idrogenato celle solari tramite bonifico stampa

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 Views.  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.

Video: 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.

Celle in silicio policristallino solari a film sottile con plasmoniche-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 ...

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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.

Un metodo per fabbricare nanostrutture d&#39;argento disconnesse in 3D

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

Optical Trapping of Nanoparticles

Optical trapping is a technique for immobilizing and manipulating small objects in a gentle way using light, and it has been widely applied in trapping and manipulating small biological particles. Ashkin and co-workers first demonstrated optical tweezers using a single focused beam1. The single beam trap can be described accurately using the perturbative gradient force formulation in the case of small Rayleigh regime particles1. In the perturbative regime, the optical power required for trapping a particle scales as the inverse fourth power of the particle size. High optical powers can damage dielectric particles and cause heating. For instance, trapped latex spheres of 109 nm in diameter were destroyed by a 15 mW beam in 25 sec1, which has serious implications for biological matter2,3.
A self-induced back-action (SIBA) optical trapping was proposed to trap 50 nm polystyrene spheres in the non-perturbative regime4. In a non-perturbative regime, even a small particle with little permittivity contrast to the background can influence significantly the ambient electromagnetic field and induce a large optical force. As a particle enters an illuminated aperture, light transmission increases dramatically because of dielectric loading. If the particle attempts to leave the aperture, decreased transmission causes a change in momentum outwards from the hole and, by Newton's Third Law, results in a force on the particle inwards into the hole, trapping the particle. The light transmission can be monitored; hence, the trap can become a sensor. The SIBA trapping technique can be further improved by using a double-nanohole structure.
The double-nanohole structure has been shown to give a strong local field enhancement5,6. Between the two sharp tips of the double-nanohole, a small particle can cause a large change in optical transmission, thereby inducing a large optical force. As a result, smaller nanoparticles can be trapped, such as 12 nm silicate spheres7 and 3.4 nm hydrodynamic radius bovine serum albumin proteins8. In this work, the experimental configuration used for nanoparticle trapping is outlined. First, we detail the assembly of the trapping setup which is based on a Thorlabs Optical Tweezer Kit. Next, we explain the nanofabrication procedure of the double-nanohole in a metal film, the fabrication of the microfluidic chamber and the sample preparation. Finally, we detail the data acquisition procedure and provide typical results for trapping 20 nm polystyrene nanospheres.

The following setup approach details low power optical trapping of dielectric nanoparticles using a double-nanohole in metal film.

Trapping ottica di nanoparticelle

Optical trapping is a technique for immobilizing and manipulating small objects in a gentle way using light, and it has been widely applied in trapping ...

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%.

Rendere record efficienza SnS celle solari per evaporazione termica e 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 ...

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.

Luce migliorato Acido fluoridrico passivazione: una tecnica sensibile per il rilevamento di difetti Silicon Bulk

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.

La stampa Fabbricazione di massa eterogiunzione celle solari e<em&gt; In Situ</em&gt; Morfologia Caratterizzazione

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%.

La stampa digitale di biossido di titanio per le celle solari dye sensibilizzato

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.

Cationi monovalenti doping di CH<sub&gt; 3</sub&gt; NH<sub&gt; 3</sub&gt; PBI<sub&gt; 3</sub&gt; Per efficienti celle solari 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.

Le sfide in reologico Caratterizzazione di sospensioni altamente concentrato - un caso di studio per la serigrafia paste d&#39;argento

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 Monitoraggio del degrado prestazioni accelerate di celle e moduli solari: un caso di studio per le celle solari di 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 ...