This work was carried out in the framework of the project &#8220;MIRAGE,&#8221; funded by the European Commission within the FP7 program.

1. LIFT-destekli flip-çip Bağlar NOT: Orada, ASANSÖR-destekli flip-çip meclisleri, ASANSÖR tekniği kullanılarak yüzeylerin yani mikro-darbeleme hayata termo-sıkıştırma flip-çip bağlama yöntemi kullanılarak çarptı yüzeylere optoelektronik cips takılarak katılan üç aşaması vardır, ve gümrüklü meclislerinin nihayet kapsülleme. Bu aşamaların her biri, aşağıdaki bölümlerde ele alınmaktadır: <ol><li> LIFT kullanarak Mikro-darbeleme: <ol><li> Verici hazırlanması için, bir lazer şeffaf taşıyıcı tabaka üzerine verici malzemeden ince bir film oluşturur. Bu deney için, boyutları ile birlikte cam taşıyıcısı alt-tabaka üzerine indiyum metal bir 200 nm kalınlığında bir filmi buharlaşması: 2 inç çapında x 0.05 cm kalınlığında. NOT: Donör hazırlama yöntemi, örneğin, buharlaşma kullanmak ve katı faz donör malzemeler için püskürtme ve spin-kaplama ve doktor-blading sıvı-faz donör için, donör malzemenin faz bağlıdırs. </li><li> Alıcı hazırlanması için, alıcı olarak 5 x 5 x 0.07 cm 3 boyutlarında cam alt-tabakaları kullanmaktadır. Desen fotolitografi kullanarak yapıların sondalama OE çip ve fan-out yapıştırılması için metalik temas yastıkları ile bu yüzeyler. Bu deney için, desen 4 mikron kalınlığında Ni-Au bağ pedleri ve fan-out cam alıcı yüzeylerde parça sondalama. </li><li> Sonraki, alıcı ile temas donör koyun ve bir bilgisayar kontrollü XY çeviri sahneye donör-alıcı düzeneğini monte edin. Not: verici bir maddenin (örneğin, bir katı madde (indiyum) ya da sıvı (mürekkep / yapıştırma)) ve bunun kalınlığı, verici ve alıcı alt-tabakaların aşamasına bağlı olarak kolayca ör göre (kontrol edilebilir optimum ayırma yerleştirilir ) metalik pulları kullanarak. </li><li> Donör substrat boyunca ışın (20 mikron spot büyüklüğü) 160 mm odak uzaklığı objektif lens kullanan taşıyıcı verici arayüzünde olay lazer ışını Odak ve taramaAlıcı bağ-pedleri üzerine donör mikro-diken diken aktarmak için e. 270 mJ / cm 2 bir akıcılığa de alıcı bağ-pedleri üzerine indiyum darbelere ASANSÖR 355 nm dalga boyunda ve 12 Yönlendirme ve İcra Komitesinin darbe süresi bir pikosaniye lazer kaynağı kullanın. NOT: enerji gibi lazer özellikleri, hayır. bakliyat, objektif lens yüksekliği, baskı donör mikro-darbe için alıcı substrat ve doğru bir bilgisayar programı tarafından kontrol edilir transfer edilmek istenen desen hassas konumu koordinatları. Anahtar deney parametreleri (örneğin, aktarma akıcılık) bir lazer kaynağı kullanarak halinde optimize edilmesi gerekir. </li><li> Kalın diken diken taze alana donör hareket ve adım 1.1.4 birkaç kez tekrarlayın için. Örneğin, bu deney için birbirlerinin üstüne basılmış 6 indiyum diken diken yığınını almak için adım 1.1.4 altı kez tekrarlayın. Nihai darbe 1.5 um ~ ortalama yüksekliği ve 20 um (Şekil 2) bir çapa sahiptir kaldırdı. NOT: Bu experim içinveliler darbelere yüzey profili ve kalınlığı bir optik profilometre kullanılarak ölçüldü. (Şekil 3 sarı işaretli) Bu diken diken 1.5 mikron ortalama kalınlıkta bir dışbükey / kubbe morfolojisi olduğu incelendi, yumru çapı üzerinde ortalama. Bunun nedeni, verici lazer ışınlanmış bölümü içinde eritildiği ve transfer Pelet daha sonra (İndiyum, düşük bir erime noktasına sahiptir) alıcı yüzeyine ulaşan üzerine yeniden katılaşan gerçeğine atfedilebilir. Bu avantajı VCSEL temas pedleri basılı yumru iyi yapışma sonuçları olmasıdır. </li></ol></li><li> Chip termo-sıkıştırma bağ alt tabakaya (4-6 Şekil): <ol><li> Çarptın yüzeylere optoelektronik fiş bağlanması için bir yarı otomatik flip-çip birleştirici, kullanın. </li><li> Çarptın alıcı ve yonga yapıştırıcının kendi vakum plakalar üzerine yapıştırılacak yükleyin. Aktif alan fac ile, yani, bir saygısız pozisyonda çip yerleştirinAşağı ing. </li><li> Uygun bir pick-up aracı kullanın ve çip ortasına hizalayın. Şekil 5&#39;te gösterildiği gibi bir iğne şeklinde aracını kullanın. Sonra, bu pick-up aracı kullanarak çip almak. </li><li> Bir kamera hizalama sistemi kullanılarak alıcı substrat üzerinde ilgili irtibat yastıkları ile çip bağ-yastıkları aynı hizaya getirin. </li><li> Bir kez yerde alt tabaka üzerinde çip uyumlu. </li><li> Elektrik ve mekanik bağlantıları alt tabakaya çip gerçekleştirmek için aynı anda ısı (~ 200 ° C) ve basınç (12.5 gf / yumru) uygulayın. </li></ol></li><li> Gümrüklü meclisleri (4-6 Şekil) kapsülleme: <ol><li> Bir şırınga iğnesi kullanarak gümrüklü montaj kenarlarında bir optik şeffaf yapışkan dağıtın. kapsülleme bağlı meclislerinin mekanik güvenilirliğini artırır. Bağlanmış fiş kapsüllenmesi için NOA 86 gibi tek bir bileşen UV yapıştırıcı kullanın. </li><li> ~ 30 sn için UV lamba kullanarak yapışkan Cure. </li></ol></li></ol> Gümrüklü Dikey boşluğu Yüzey yayan Lazerlerin 2. Karakterizasyonu (VCSEL) NOT: imalat sonra bir sonraki adım bağlı meclislerinin elektro-optik performansını değerlendirmek için. cihazların ışık akım-gerilim (LIV) eğrileri bir prob istasyonu kullanarak post-yapıştırma kaydedilir. Aşağıdaki adımlar test için katılmaktadırlar: <ol><li> Bir ısmarlama şeffaf sahneye cihazı bağlı Flip-çip yerleştirin. sahne VCSEL yaydığı ışığın kolay erişim için merkezi delinmiş bir delik vardır. </li><li> Şeffaf aşamada altında fotodetektörü (PD) yerleştirin ve bir mikroskop kullanılarak bağlanmış çip ile aktif alanı hizalayın. </li><li> Kesinlikle bir mikroskop kullanılarak pedleri sondalama Ni-Au üzerinde sondalama iğne yerleştirin. </li><li> Mevcut 10 mA kadar enjekte ve VCSEL üzerinde gerilim düşümü ve akım / gerilim kaynağı metre birimini kullanarak onun tarafından yayılan ışık ve güç metre res ölçmekpectively. </li></ol>

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The authors have nothing to disclose.

Bu yazıda, ASANSÖR denilen bir lazer tabanlı doğrudan yazma tekniği kullanılarak tek VCSEL cips termo-sıkıştırma flip-çip bağ göstermiştir. ASANSÖR tekniği kullanılarak substrat temas pedleri üzerine indiyum mikro-darbe baskı dahil montaj üretim aşamaları. Bu ısıyla sıkıştırma flip-chip çarptı substratlara VCSEL yongaları yapıştırma ve son olarak da kapsülleme izledi. ASANSÖR-destekli bağlı cips, elektrik, optik ve mekanik güvenilirlik onların LIV eğr...

Lazer kaynaklı İleri Transferi (LIFT) tek adım desen tanımı ve mikron ve alt mikron çözünürlüklü malzeme transferi için çok yönlü direkt yazmak katkı üretim yöntemidir. Bu yazıda, bir çip-ölçekte dikey-oyuk yüzey yayan lazerler (VCSEL) flip-çip paketleme için darbeleme tekniği olarak LIFT kullandığını rapor. Flip-çip sistemi ambalaj ve elektronik ve optoelektronik (OE) bileşenlerinin entegrasyonu önemli bir teknolojidir. Bileşenlerinin yoğun entegrasyonu sağlamak amacıyla ince adımlı bağlama gereklidir. Ince bacaklı yapıştırma standart tekniklerle bazı gösterdiği ancak esneklik, maliyet-etkililik, hız, doğruluk ve düşük işlem sıcaklığı gibi diğer önemli özellikleri biraraya açısından bir boşluk var olmasına rağmen. Bu gereksinimleri karşılamak için biz OE bileşenleri ince ziftinin için LIFT-destekli termo-sıkıştırma yapıştırma yöntemi göstermektedir. L iseIFT (verici olarak da adlandırılır) basılacak malzemenin ince bir film (taşıyıcı madde olarak da adlandırılır), bir lazer şeffaf destek alt-tabakanın bir yüzeyi üzerine tatbik edilir. 1 Bu tekniğin temel prensibini gösterir, Şekil. Yetecek bir şiddete sahip bir olay Lazer darbesinin ardından yakın yerleştirilir (alıcısı olarak da adlandırılır) bir alt-tabaka üzerine ışınlanmış bölgeden verici piksel transferi iletmek için gerekli olan tahrik kuvveti sağlar taşıyıcı verici arayüzünde odaklanmıştır. ASANSÖR ilk hasarlı fotoğraf maskeler 3 onarımı için mikron büyüklüğünde bakır hatları yazdırmak için bir teknik olarak Bohandy tarafından 1986 yılında rapor edilmiştir. Ilk gösteri yana bu teknik seramik 4 CNTs 5, QDS 6 gibi malzemelerin geniş bir kontrol desen ve baskı, canlı hücreler 7, grafik boyunca bir mikro nano üretim teknolojisi gibi önemli ilgi görürene 8 gibi biyo-sensörler 9, OLEDler 10, optoelektronik bileşenlerin 11, plasmonik sensörler 12, organik-elektronik 13 ve flip-chip yapıştırma 14,15 gibi çeşitli uygulamalar için. ASANSÖR gibi OE bileşenleri flip-çip paketleme için sadelik, hız, esneklik, maliyet-etkililik, yüksek çözünürlük ve doğruluk gibi mevcut Flip-çip sarsıntı ve yapıştırma teknikleri üzerinde çeşitli avantajlar sunuyor.

<table border="0" cellpadding="0" cellspacing="0" width="663">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:161px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Laser source</td>
			<td style="width:161px;">3D MicroMac (3DMM)</td>
			<td style="width:119px;">2912-295</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Photodetector</td>
			<td style="width:161px;">Newport&#160;</td>
			<td style="width:119px;">818 series</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Source measurement unit</td>
			<td style="width:161px;">Keithley&#160;</td>
			<td style="width:119px;">2401</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Power meter</td>
			<td style="width:161px;">Newport&#160;</td>
			<td style="width:119px;">1930</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Underfill</td>
			<td style="width:161px;">Norlands</td>
			<td style="width:119px;">NOA 86</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">UV lamp</td>
			<td style="width:161px;">Omnicure</td>
			<td style="width:119px;">Series 1000 UV</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Probe station</td>
			<td style="width:161px;">Cascade Microtech</td>
			<td style="width:119px;">model 42</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Flip-chip bonder</td>
			<td style="width:161px;">Dr. Tresky</td>
			<td style="width:119px;">T-320 X</td>
			<td></td>
		</tr>
	</tbody>
</table>

laser-induced forward transfer for flip-chip packaging of single dies

Flip-çip (FC) ambalaj mikro-elektronik sektöründe yüksek performans, minyatür ultra yüksek yoğunluklu devreleri gerçekleştirmek için bir anahtar teknolojidir. Bu teknikte çipi ve / veya alt-tabaka bombelidir ve iki bu iletken darbe ile bağlanır. Birçok çarpma teknikleri geliştirilmiş ve yoğun 1960 1 gibi şablon baskı, damızlık darbeleme, buharlaşma ve elektriksiz olarak / 2 galvanik FC teknolojisinin girmesiyle incelenmiştir. Bu yöntemler hepsi birinden muzdarip ya da maliyet karmaşık işlem adımları, yüksek işlem sıcaklıkları, imalat süresi ve esneklik en önemlisi eksikliği gibi ele alınması gereken birden fazla dezavantajları yapmış olduğu ilerlemeye rağmen. Bu yazıda Lazer kaynaklı İleri Transferi (ASANSÖR) olarak bilinen basit ve maliyet-etkin bir lazer tabanlı yumru oluşturan tekniği 3 göstermektedir. ASANSÖR tekniktir çarpmak malzemeleri geniş bir yelpazede kullanarak olabilir bOda sıcaklığında büyük esneklik, yüksek hız ve doğruluk ile tek aşamada basılabilir ör. Buna ek olarak, ASANSÖR ultra minyatür devreyi imalatı için kritik çip ölçekli, aşağı darbeleme ve yapıştırma sağlar.

Şekil 7, birçok flip-çip bağlı VCSEL cips birinden kaydedildi tipik bir LIV eğrisini göstermektedir. Tedarikçiye ölçülen optik güç arasında bir iyi bir maç değerleri bağlı cihazlar sonrası bağ başarılı işleyişini belirtilen alıntı. Eğimler aynı zamanda, prior- ve post-kapsülleme kaydedildi ve karşılaştırma üzerine, bunun (Şekil 7 &#39;de gösterildiği gibi) kapsülleyici talaş işlevselliği etkisi olduğunu teyit edilmiştir. Ayrıca, Flip-çip ba?...

Watch this Scientific Journal Video about Laser-induced Forward Transfer for Flip-chip Packaging of Single Dies at JoVE.com

Laser-induced Forward Transfer for Flip-chip Packaging of Single Dies

Biz optoelektronik bileşenlerin flip-çip montaj Lazer kaynaklı İleri Transferi (LIFT) tekniğinin kullanımını göstermektedir. Bu yaklaşım, basit, maliyet-etkin, düşük-sıcaklık, optoelektronik uygulamalar için yüksek yoğunluklu devreleri ulaşmak için çip-ölçekte darbeleme ince perde ve yapıştırılması için hızlı ve esnek bir çözüm sağlar.

Tek Dies Flip-çip Ambalaj Lazer kaynaklı İleri Transferi

Flip-chip (FC) packaging is a key technology for realizing high performance, ultra-miniaturized and high-density circuits in the micro-electronics ...

laser-induced-forward-transfer-for-flip-chip-packaging-of-single-dies

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JoVE Journal

Engineering

12.2K Görüntüleme.  Ghent University-imec.  Biz optoelektronik bileşenlerin flip-çip montaj Lazer kaynaklı İleri Transferi (LIFT) tekniğinin kullanımını göstermektedir. Bu yaklaşım, basit, maliyet-etkin, düşük-sıcaklık, optoelektronik uygulamalar için yüksek yoğunluklu devreleri ulaşmak için çip-ölçekte darbeleme ince perde ve yapıştırılması için hızlı ve esnek bir çözüm sağlar. 

Video: Laser-induced Forward Transfer for Flip-chip Packaging of Single Dies

Compact Quantum Dots for Single-molecule Imaging

Single-molecule imaging is an important tool for understanding the mechanisms of biomolecular function and for visualizing the spatial and temporal heterogeneity of molecular behaviors that underlie cellular biology 1-4. To image an individual molecule of interest, it is typically conjugated to a fluorescent tag (dye, protein, bead, or quantum dot) and observed with epifluorescence or total internal reflection fluorescence (TIRF) microscopy. While dyes and fluorescent proteins have been the mainstay of fluorescence imaging for decades, their fluorescence is unstable under high photon fluxes necessary to observe individual molecules, yielding only a few seconds of observation before complete loss of signal. Latex beads and dye-labeled beads provide improved signal stability but at the expense of drastically larger hydrodynamic size, which can deleteriously alter the diffusion and behavior of the molecule under study.
Quantum dots (QDs) offer a balance between these two problematic regimes. These nanoparticles are composed of semiconductor materials and can be engineered with a hydrodynamically compact size with exceptional resistance to photodegradation 5. Thus in recent years QDs have been instrumental in enabling long-term observation of complex macromolecular behavior on the single molecule level. However these particles have still been found to exhibit impaired diffusion in crowded molecular environments such as the cellular cytoplasm and the neuronal synaptic cleft, where their sizes are still too large 4,6,7.
Recently we have engineered the cores and surface coatings of QDs for minimized hydrodynamic size, while balancing offsets to colloidal stability, photostability, brightness, and nonspecific binding that have hindered the utility of compact QDs in the past 8,9. The goal of this article is to demonstrate the synthesis, modification, and characterization of these optimized nanocrystals, composed of an alloyed HgxCd1-xSe core coated with an insulating CdyZn1-yS shell, further coated with a multidentate polymer ligand modified with short polyethylene glycol (PEG) chains (Figure 1). Compared with conventional CdSe nanocrystals, HgxCd1-xSe alloys offer greater quantum yields of fluorescence, fluorescence at red and near-infrared wavelengths for enhanced signal-to-noise in cells, and excitation at non-cytotoxic visible wavelengths. Multidentate polymer coatings bind to the nanocrystal surface in a closed and flat conformation to minimize hydrodynamic size, and PEG neutralizes the surface charge to minimize nonspecific binding to cells and biomolecules. The end result is a brightly fluorescent nanocrystal with emission between 550-800 nm and a total hydrodynamic size near 12 nm. This is in the same size range as many soluble globular proteins in cells, and substantially smaller than conventional PEGylated QDs (25-35 nm).

We describe the preparation of colloidal quantum dots with minimized hydrodynamic size for single-molecule fluorescence imaging. Compared to conventional quantum dots, these nanoparticles are similar in size to globular proteins and are optimized for single-molecule brightness, stability against photodegradation, and resistance to nonspecific binding to proteins and cells.

Tek molekül Görüntüleme için kompakt Kuantum Noktaları

Single-molecule imaging is an important tool for  understanding the mechanisms of biomolecular function and for visualizing the  spatial and temporal ...

Mühendislik

Analysis of Contact Interfaces for Single GaN Nanowire Devices

Single GaN nanowire (NW) devices fabricated on SiO2 can exhibit a strong degradation after annealing due to the occurrence of void formation at the contact/SiO2 interface. This void formation can cause cracking and delamination of the metal film, which can increase the resistance or lead to a complete failure of the NW device. In order to address issues associated with void formation, a technique was developed that removes Ni/Au contact metal films from the substrates to allow for the examination and characterization of the contact/substrate and contact/NW interfaces of single GaN NW devices. This procedure determines the degree of adhesion of the contact films to the substrate and NWs and allows for the characterization of the morphology and composition of the contact interface with the substrate and nanowires. This technique is also useful for assessing the amount of residual contamination that remains from the NW suspension and from photolithographic processes on the NW-SiO2 surface prior to metal deposition. The detailed steps of this procedure are presented for the removal of annealed Ni/Au contacts to Mg-doped GaN NWs on a SiO2 substrate.

A technique was developed that removes Ni/Au contact metal films from their substrate to allow for the examination and characterization of the contact/substrate and contact/NW interfaces of single GaN nanowire devices.

Tek GaN Nanotel Cihazlar İletişim arabirimleri Analizi

Single GaN nanowire (NW) devices fabricated on SiO2 can exhibit  a strong degradation after annealing due to the  occurrence of void formation at the ...

Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown

In this work, we present time-resolved measurements of atomic and diatomic spectra following laser-induced optical breakdown. A typical LIBS arrangement is used. Here we operate a Nd:YAG laser at a frequency of 10 Hz at the fundamental wavelength of 1,064 nm. The 14 nsec pulses with anenergy of 190 mJ/pulse are focused to a 50 &#181;m spot size to generate a plasma from optical breakdown or laser ablation in air. The microplasma is imaged onto the entrance slit of a 0.6 m spectrometer, and spectra are recorded using an 1,800 grooves/mm grating an intensified linear diode array and optical multichannel analyzer (OMA) or an ICCD. Of interest are Stark-broadened atomic lines of the hydrogen Balmer series to infer electron density. We also elaborate on temperature measurements from diatomic emission spectra of aluminum monoxide (AlO), carbon (C2), cyanogen (CN), and titanium monoxide (TiO).
The experimental procedures include wavelength and sensitivity calibrations. Analysis of the recorded molecular spectra is accomplished by the fitting of data with tabulated line strengths. Furthermore, Monte-Carlo type simulations are performed to estimate the error margins. Time-resolved measurements are essential for the transient plasma commonly encountered in LIBS.

Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown

Time-resolved atomic and diatomic molecular species are measured using LIBS. The spectra are collected at various time delays following the generation of optical breakdown plasma with Nd:YAG laser radiation&#160;and are analyzed to infer electron density and temperature.

Ölçme ve Atomik Hidrojen ve iki atomlu moleküler AIO, C Analizi<sub&gt; 2</sub&gt;, CN, ve TiO Spectra takiben lazer kaynaklı Optik Dağılımı

In this work, we present time-resolved measurements of atomic and diatomic spectra following laser-induced optical breakdown. A typical LIBS arrangement ...

Laser-induced Breakdown Spectroscopy: A New Approach for Nanoparticle's Mapping and Quantification in Organ Tissue

Emission spectroscopy of laser-induced plasma was applied to elemental analysis of biological samples. Laser-induced breakdown spectroscopy (LIBS) performed on thin sections of rodent tissues: kidneys and tumor, allows the detection of inorganic elements such as (i) Na, Ca, Cu, Mg, P, and Fe, naturally present in the body and (ii) Si and Gd, detected after the injection of gadolinium-based nanoparticles. The animals were euthanized 1&#160;to 24 hr&#160;after intravenous injection of particles. A two-dimensional scan of the sample, performed using a motorized micrometric 3D-stage, allowed the infrared laser beam exploring the surface with a lateral resolution less than 100 &#956;m. Quantitative chemical images of Gd element inside the organ were obtained with sub-mM sensitivity. LIBS offers a simple and robust method to study the distribution of inorganic materials without any specific labeling. Moreover, the compatibility of the setup with standard optical microscopy emphasizes its potential to provide multiple images of the same biological tissue with different types of response:&#160;elemental, molecular, or cellular.

Laser-induced Breakdown Spectroscopy: A New Approach for Nanoparticle&#039;s Mapping and Quantification in Organ Tissue

Laser-induced breakdown spectroscopy performed on thin organ and tumor tissue successfully detected natural elements and artificially injected gadolinium (Gd), issued from Gd-based nanoparticles. Images of chemical elements reached a resolution of 100 &#956;m and quantitative sub-mM sensitivity. The compatibility of the setup with standard optical microscopy emphasizes its potential to provide multiple images of a same biological tissue.

Lazer kaynaklı Arıza Spektroskopisi: Organ Doku Nanopartikülün en Mapping ve Nicelik için Yeni Bir Yaklaşım

Emission spectroscopy of laser-induced plasma was applied to elemental analysis of biological samples. Laser-induced breakdown spectroscopy (LIBS) ...

Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping

As mass-produced silicon transistors have reached the nano-scale, their behavior and performances are increasingly affected, and often deteriorated, by quantum mechanical effects such as tunneling through single dopants, scattering via interface defects, and discrete trap charge states. However, progress in silicon technology has shown that these phenomena can be harnessed and exploited for a new class of quantum-based electronics. Among others, multi-layer-gated silicon metal-oxide-semiconductor (MOS) technology can be used to control single charge or spin confined in electrostatically-defined quantum dots (QD). These QD-based devices are an excellent platform for quantum computing applications and, recently, it has been demonstrated that they can also be used as single-electron pumps, which are accurate sources of quantized current for metrological purposes. Here, we discuss in detail the fabrication protocol for silicon MOS QDs which is relevant to both quantum computing and quantum metrology applications. Moreover, we describe characterization methods to test the integrity of the devices after fabrication. Finally, we give a brief description of the measurement set-up used for charge pumping experiments and show representative results of electric current quantization.

The fabrication process and experimental characterization techniques relevant to single-electron pumps based on silicon metal-oxide-semiconductor quantum dots are discussed.

Tek elektron pompalayabilme için Silikon Metal-oksit-yarıiletken Kuantum Noktaları

As mass-produced silicon transistors have reached the nano-scale, their behavior and performances are increasingly affected, and often deteriorated, by ...

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.

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.

Transfer Baskı ile Hidrojene Mikrokristal Silikon Güneş Pilleri Işık Yakalama Gümüş Nanoyapıların Entegrasyonu

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

Laser-induced Forward Transfer of Ag Nanopaste

Over the past decade, there has been much development of non-lithographic methods1-3 for printing metallic inks or other functional materials. Many of these processes such as inkjet3 and laser-induced forward transfer (LIFT)4 have become increasingly popular as interest in printable electronics and maskless patterning has grown. These additive manufacturing processes are inexpensive, environmentally friendly, and well suited for rapid prototyping, when compared to more traditional semiconductor processing techniques. While most direct-write processes are confined to two-dimensional structures and cannot handle materials with high viscosity (particularly inkjet), LIFT can transcend both constraints if performed properly. Congruent transfer of three dimensional pixels (called voxels), also referred to as laser decal transfer (LDT)5-9, has recently been demonstrated with the LIFT technique using highly viscous Ag nanopastes to fabricate freestanding interconnects, complex voxel shapes, and high-aspect-ratio structures. In this paper, we demonstrate a simple yet versatile process for fabricating a variety of micro- and macroscale Ag structures. Structures include simple shapes for patterning electrical contacts, bridging and cantilever structures, high-aspect-ratio structures, and single-shot, large area transfers using a commercial digital micromirror device (DMD) chip.

We demonstrate the use of the Laser-induced forward transfer technique (LIFT) for the printing of high-viscosity Ag paste. This technique offers a simple, low temperature, robust process for non-lithographically printing microscale 2D and 3D structures.

Ag Nanopaste lazer kaynaklı İleri Transferi

Over the past decade, there has been much development of non-lithographic methods1-3 for printing metallic inks or other functional materials. Many of ...

Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation

We present a protocol for fabricating 1-D Photonic Crystal (PhC) cavities on subwavelength-diameter tapered optical fibers, optical nanofibers, using femtosecond laser-induced ablation. We show that thousands of periodic nano-craters are fabricated on an optical nanofiber by irradiating with just a single femtosecond laser pulse. For a typical sample, periodic nano-craters with a period of 350 nm and with diameter gradually varying from 50 - 250 nm over a length of 1 mm are fabricated on a nanofiber with diameter around 450 - 550 nm. A key aspect of such a nanofabrication is that the nanofiber itself acts as a cylindrical lens and focuses the femtosecond laser beam on its shadow surface. Moreover, the single-shot fabrication makes it immune to mechanical instabilities and other fabrication imperfections. Such periodic nano-craters on nanofiber, act as a 1-D PhC and enable strong and broadband reflection while maintaining the high transmission out of the stopband. We also present a method to control the profile of the nano-crater array to fabricate apodized and defect-induced PhC cavities on the nanofiber. The strong confinement of the field, both transverse and longitudinal, in the nanofiber-based PhC cavities and the efficient integration to the fiber networks, may open new possibilities for nanophotonic applications and quantum information science.

We present a protocol for fabricating 1-D photonic crystal cavities on subwavelength diameter silica fibers (optical nanofibers) using femtosecond laser-induced ablation.

Femtosaniye Lazer kaynaklı Ablasyonu kullanarak nanolif 1-D Fotonik Kristal Kavitenin Fabrikasyon

We present a protocol for fabricating 1-D Photonic Crystal (PhC) cavities on subwavelength-diameter tapered optical fibers, optical nanofibers, using ...

Scanning Light Scattering Profiler (SLPS) Based Methodology to Quantitatively Evaluate Forward and Backward Light Scattering from Intraocular Lenses

The scanning light scattering profiler (SLSP) methodology has been developed for the full-angle quantitative evaluation of forward and backward light scattering from intraocular lenses (IOLs) using goniophotometer principles. This protocol describes the SLSP platform and how it employs a 360&#176; rotational photodetector sensor that is scanned around an IOL sample while recording the intensity and location of scattered light as it passes through the IOL medium. The SLSP platform can be used to predict, non-clinically, the propensity for current and novel IOL designs and materials to induce light scatter. Non-clinical evaluation of light scattering properties of IOLs can significantly reduce the number of patient complaints related to unwanted glare, glistening, optical defects, poor image quality, and other phenomena associated with the unintended light scattering. Future studies should be conducted to correlate SLSP data with clinical results to help identify which measured light scatter is most problematic for patients that have undergone cataract surgery subsequent to IOL implantation.

Scanning Light Scattering Profiler SLPS Based Methodology to Quantitatively Evaluate Forward and Backward Light Scattering from Intraocular Lenses

This protocol describes the scanning light scattering profiler (SLSP) that enables the full-angle quantitative evaluation of forward and backward scattering of light from intraocular lenses (IOLs) using goniophotometer principles.

Işık saçılma Profiler (SLPS) Tabanlı Metodoloji İntraoküler Lenslerden İleri ve Geri Işık Saçılımını Kantitatif Olarak Değerlendirmek İçin Tarama

The scanning light scattering profiler (SLSP) methodology has been developed for the full-angle quantitative evaluation of forward and backward light ...

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics

The miniaturization of semiconductor devices to scales where small numbers of dopants can control device properties requires the development of new techniques capable of characterizing their dynamics. Investigating single dopants requires sub-nanometer spatial resolution, which motivates the use of scanning tunneling microscopy (STM). However, conventional STM is limited to millisecond temporal resolution. Several methods have been developed to overcome this shortcoming, including all-electronic time-resolved STM, which is used in this study to examine dopant dynamics in silicon with nanosecond resolution. The methods presented here are widely accessible and allow for local measurement of a wide variety of dynamics at the atomic scale. A novel time-resolved scanning tunneling spectroscopy technique is presented and used to efficiently search for dynamics.

We demonstrate an all-electronic method to observe nanosecond-resolved charge dynamics of dopant atoms in silicon with a scanning tunneling microscope.

Tüm elektronik Nanosecond çözüldü tarama tünelleme mikroskobu: tek Dopant şarj Dynamics incelenmesi kolaylaştırılması

The miniaturization of semiconductor devices to scales where small numbers of dopants can control device properties requires the development of new ...