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アシストフリップチップボンディング注：あり、LIFTアシストフリップチップアセンブリ、LIFT技術を用いて基材、すなわち、マイクロバンプを実現する熱圧着フリップチップボンディング法を用いてバンプ基板に光電子チップを取り付ける際には、三つの段階であり、かつ最終的に結合したアセンブリのカプセル化。これらの段階のそれぞれは、次のセクションで説明します： <ol><li>リフトを使用マイクロバンピング： <ol><li>ドナーの準備のために、レーザー透過性キャリア基板上にドナー材料の薄膜を堆積させる。 2インチ径のx 0.05センチメートル厚：この実験では、寸法のガラスキャリア基板の上にインジウム金属の厚さ200nmの膜を蒸発させる。 注：ドナー調製方法は、例えば、蒸発を使用して、固相ドナー材料スパッタリング及びスピンコーティングおよびドクターブレードの液相ドナーについて、ドナー材料の相に依存するS。 </li><li>受信機の製造のために、受信機などの5×5×0.07センチメートル3の寸法を有するガラス基板を用いる。パターンフォトリソグラフィを用いて構造プロービングOEチップとファンアウトを接合するための金属接触パッドと、これらの基板。この実験では、パターン厚さ4μmのNi-Auのボンドパッドとファンアウトをガラスレシーバ基板上にトラックを探索する。 </li><li>次に、受信機と接触してドナーを配置し、コンピュータ制御のXY移動ステージ上にドナー - 受信機アセンブリをマウントします。 注：ドナー材料の相（ 例えば、固体（インジウム）または液体（インク/ペースト））及びその厚さは、ドナーに依存し、レシーバ基板を容易に制御することができる最適な分離に配置されている（ 例えば、バイ）金属製のスペーサを使って。 </li><li> 160ミリメートルの焦点距離の対物レンズを用いたキャリア供与体界面に入射したレーザビームを集束し、ドナーsubstratにわたってビーム（20μmのスポットサイズ）をスキャン受信機のボンドパッド上にドナーマイクロバンプを転送するための電子。 270 MJ / cm 2のフルエンスでレシーバボンドパッド上にインジウムバンプを持ち上げるために355 nmの波長と12ピコ秒のパルス持続時間のピコ秒レーザー光源を使用してください。 注：このようなエネルギーなどのレーザ特性、ない。パルスは、対物レンズの高さを、ドナーマイクロバンプ転写されるべき所望のパターンを印刷するためのレシーバ基板上の正確な位置の座標を正確にコンピュータプログラムによって制御される。重要な実験パラメータ（ 例えば、転写フルエンス）は、他のレーザ光 ​​源を用いた場合に最適化される必要がある。 </li><li>厚いバンプのために数回、新鮮な領域にドナーを移動し、ステップ1.1.4を繰り返します。例えば、この実験のために、互いの上に印刷された6インジウムバンプのスタックを取得するために6回ステップ1.1.4を繰り返す。最終的には、バンプは〜1.5μmで20μmの直径（ 図2）の平均高さを持って持ち上げた。 注：これらのexperimについてエントバンプの表面形状と厚さは、光学プロフィロメータを用いて測定した。これは、バンプが1.5μmの平均厚さと、凸/ドーム形態を有し、（ 図3に黄色でマークされたように）、バンプ径にわたって平均化することを検討した。その理由は、ドナーは、レーザ照射ゾーン中で溶融し、ペレットを移し、次いで（インジウム、低融点を有する）受容体表面に到達した時点で再固化するという事実に起因する。これの利点は、VCSELの接触パッドに印刷されたバンプの良好な接着をもたらすことである。 </li></ol></li><li>熱圧着（ 図4-6）基板へのチップ： <ol><li>ぶつかった基板に光電子チップを接合するための半自動フリップチップボンダーを使用してください。 </li><li>ぶつかった受信機とボンダのそれぞれの真空プレートに接合されるチップをロードします。そのアクティブエリアFACで、すなわち 、反転した位置にチップを置きますダウンる。 </li><li>適切なピックアップツールを使用して、チップの中心に位置に合わせます。 図5に示すように、針状のツールを使用します。次に、このピックアップツールを使用してチップを選択します。 </li><li>カメラ·アライメントシステムを使用してレシーバ基板上の対応する接触パッドとチップボンドパッドの位置を合わせます。 </li><li>いったん整列すると、基板上にチップを置く。 </li><li>電気的および機械的な相互接続を基板へチップを実現すると同時に熱（〜200℃）および圧力（12.5重/バンプ）を適用する。 </li></ol></li><li>結合したアセンブリ（ 図4-6）のカプセル化： <ol><li>注射針を使用して接合体​​のエッジの周りに光学的に透明な接着剤を分注する。カプセル化は、結合したアセンブリの機械的信頼性が向上します。結合したチップをカプセル化するためのNOA 86などの単一成分のUV硬化型接着剤を使用してください。 </li><li> 〜30秒間UVランプを用いて接着剤を硬化させる。 </li></ol></li></ol>ボンド垂直共振器型面発光レーザ（VCSELの）のキャラクタリゼーション注：製造後に次のステップでは、結合アセンブリの電気光学的性能を評価することである。デバイスの光電流 - 電圧（LIV）の曲線は、プローブステーションを用いて、接合後に記録されている。次のステップはテストのために関与している： <ol><li>カスタムメイドの透明ステージにデバイスをフリップチップを置きます。ステージは、VCSELはによって放射される光に簡単にアクセスするためのその中心部に孔を有している。 </li><li>透明ステージの下に光検出器（PD）を配置し、顕微鏡を用いて接着チップとの活性領域を揃える。 </li><li>正確に顕微鏡を用いたNi-Auのプロービングパッド上プロービングの針を配置。 </li><li>電流の10 mAまで注入し、VCSELの両端の電圧降下および電流/電圧ソースメータユニットとパワーメータ解像度を使用することによって放出される光を測定するpectively。 </li></ol>

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The authors have nothing to disclose.

本稿では、LIFTいわゆるレーザベースの直接描画技術を使用して単一のVCSELチップの熱圧着フリップチップボンディングを示した。 LIFT技術を用いて基板接点パッド上のインジウムのマイクロバンプの印刷を関与アセンブリの製造工程。これは、熱圧着フリップチップバンプ基板にVCSELチップボンディングし、最終的にそれらのカプセル化を行った。 LIFTアシスト結合チッ?...

レーザー誘起前方転写（LIFT）は、ミクロンおよびサブミクロンの分解能を有するシングルステップパターン定義及び物質移動のための多目的な直接書き込み添加剤の製造方法である。本稿では、チップスケールの垂直共振器型面発光レーザ（VCSEL）のフリップチップ実装用のバンプ技術としてLIFTの使用を報告している。フリップチップシステム·パッケージと電子及び光電子（OE）コンポーネントの統合における重要な技術です。部品の高密度集積化を達成するためにファインピッチ接合が不可欠である。なお、ファインピッチ·ボンディングは、標準的な技術のいくつかによって実証されているが、ボイドが、柔軟性、費用対効果、スピード、精度と低処理温度などの他の重要な特徴を一緒に組み合わせるという点であります。これらの要件を満たすために、我々は、OE部品のファインピッチボンディングのLIFT補助熱圧着法を実証する。 LでIFT、印刷される材料の薄膜（ ドナーと呼ばれる）（ キャリアとも呼ばれる）レーザー透過性支持基板の一方の面上に堆積される。 図1は、この技術の基本原理を示す図である。十分な強度の入射レーザパルスは、次に近接して配置され（ 受信機ともいう）は、別の基板上に照射されたゾーンからのドナーピクセルを転送する転送するために必要な推進力を提供するキャリア供与体界面に集光される。 リフトが最初に損傷を受けたフォトマスク3を修復するためのミクロンサイズの銅配線を印刷する技術としてBohandyによって1986年に報告された。その最初の実証以来、この技術は、セラミックス4、カーボンナノチューブ5、量子ドット6のような広範囲の材料の制御されたパターニングと、印刷、生きた細胞7、グラフのマイクロ·ナノ加工技術として大きな関心を集めているエン8、そのようなバイオセンサー9、OLEDの10、光電子部品11、プラズモンセンサー12、有機エレクトロニクス13とフリップチップボンディング14,15として多様なアプリケーションのために。 LIFTは、OE部品のフリップチップ実装のためのシンプルさ、速度、柔軟性、費用対効果、高分解能と精度などの既存のフリップチップバンプと接合技術に勝るいくつかの利点を提供する。

<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

フリップチップ（FC）パッケージは、マイクロエレクト​​ロニクス産業で高性能、超小型化、高密度回路を実現するための重要な技術である。この技術では、チップおよび/または基板がバンプされ、両者は、これらの導電性バンプを介して接合されている。多くのバンピング技術が開発され、集中的にそのようなステンシル印刷、スタッドバンピング、蒸発電解として1960年にFC技術の導入1/2を電気めっきするので、研究されてきた。これらの方法は、それらすべてが1に苦しむ又はコスト、複雑な処理ステップ、高い処理温度、製造時間及び柔軟性の最も重要な不足などに対処する必要がある複数の欠点の進捗状況にもかかわらず。本稿では、レーザ誘起フォワード転送（LIFT）として知られているシンプルでコスト効率のレーザーベースのバンプ形成技術3を示しています。 LIFT法のバンプ材料の広い範囲を使用すると、bはできRTでの大きな柔軟性、高速かつ正確に一段階で印刷電子。また、LIFTは超小型回路を製造するために重要であるチップスケール、までバンピングとの結合を可能にします。

図7は 、多くのフリップチップ接合のVCSELチップの1つから記録された典型的なLIV曲線を示す。サプライヤーに測定された光パワーとの間に良好な一致が値を引用符で囲まれた接合デバイス接合後の成功の機能を示した。曲線もprior-、ポストカプセル化を記録し、比較には（ 図7に示すように）封入剤には、チップの機能に影響を与えたことが確認されなかった。また?...

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

私たちは光電子部品のフリップチップ実装用のレーザー誘起フォワード転送（LIFT）技術の使用を示す。このアプローチは、ファインピッチの光電子用途のための高密度回路を実現するためのチップスケール上バンピングと接合するためのシンプルでコスト効率、低温、高速で柔軟なソリューションを提供する。

シングルダイのフリップチップ実装用のレーザー誘起フォワード転送

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

Research

JoVE Journal

Engineering

12.2K ビュー.  Ghent University-imec. 私たちは光電子部品のフリップチップ実装用のレーザー誘起フォワード転送（LIFT）技術の使用を示す。このアプローチは、ファインピッチの光電子用途のための高密度回路を実現するためのチップスケール上バンピングと接合するためのシンプルでコスト効率、低温、高速で柔軟なソリューションを提供する。 

ビデオ: 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.

1分子蛍光イメージングのためのコンパクトな量子ドット

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

工学

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.

シングルGaNナノ細線デバイスのための接触界面の解析

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.

測定と原子状水素と二原子分子のAlO、Cの分析<sub&gt; 2</sub&gt;、CN、およびTiOスペクトラ[次のレーザー誘起光学破壊

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.

レーザー誘起ブレークダウン分光法：臓器組織内のナノ粒子のマッピングと定量化のための新たなアプローチ

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.

単電子揚水用のシリコン金属酸化膜半導体量子ドット

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.

転写印刷により水素化微結晶シリコン太陽電池の光トラッピング銀ナノ構造の統合

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.

銀ナノペーストのレーザー誘起フォワード転送

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.

フェムト秒レーザー誘起アブレーションを用いたナノファイバー上の1次元フォトニック結晶共振器の作製

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.

眼内レンズからの前方散乱光および後方散乱光を定量的に評価するための走査型光散乱プロファイラ（SLPS）に基づく方法論

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.

すべて電子ナノ秒分解走査型トンネル顕微鏡: 単一ドーパントの電荷ダイナミクスの調査を促進します。

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