Name: laser-induced forward transfer for flip-chip packaging of single dies
Uploaded: 2015-03-20T14:00:00.000+00:00
Duration: 8 min 21 s
Description: Watch this Scientific Journal Video about Laser-induced Forward Transfer for Flip-chip Packaging of Single Dies at JoVE.com

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

1. 리프트를 이용한 플립 칩 본딩 NOTE : 거기, LIFT 이용한 플립 칩 어셈블리 LIFT 기술을 사용하여 기판 즉 마이크로 범핑 실현 열 압착 플립 칩 접합 방법을 사용하여 범프 기판에 광전자 칩 부착에 관여하는 세 단계가 있으며, 결합 어셈블리의 마지막 캡슐화. 각 단계는 다음 섹션에 설명되어 있습니다 : <ol><li> 리프트를 사용하여 마이크로 범핑 : <ol><li> 도너 준비 기간은 레이저 투과성 캐리어 기판 상에 도너 재료의 박막을 증착. 이 실험을 위해, 치수 유리 캐리어 기판 위에 인듐 금속의 200 nm 두께의 필름을 증발 : 직경 2 인치 X 0.05 cm 두께. 주 : 기부자 제조 방법은 예를 들어, 증발을 사용하여 고상 도너 재료 스퍼터링 스핀 코팅 및 닥터 블레이 딩을-액상 공여체, 도너 물질의 위상에 의존의. </li><li> 수신기 준비를 들어, 수신기 등 5 × 5 × 0.07 cm 3 차원 유리 기판을 사용합니다. 패턴을 포토 리소그래피를 이용한 구조 프로빙 OE 칩과 팬 아웃을 접합 금속 접촉 패드와 이들 기판. 이 실험을 위해, 패턴 4 μm의 두께 니켈 - 금 본드 패드 및 팬 아웃 유리 수신기 기판 상에 트랙을 프로빙. </li><li> 다음으로, 수신기와 접촉하는 기증자를 배치하고 컴퓨터 제어 XY 번역 무대에 기증자 수신기 어셈블리를 탑재합니다. 참고 : 도너 재료 (예를 들면, 고체 (인듐) 또는 액체 (잉크 / 페이스트)) 그 두께, 도너와 수신기의 기판 상에 따라 쉽게 예 그래피 (제어 될 수 최적의 분리에 배치되고 ) 금속 스페이서를 사용. </li><li> 도너 substrat 통하여 상기 빔 (20 μm의 스폿 크기)를 초점 거리 160mm의 대물 렌즈를 채용 캐리어 도너 계면에 입사 레이저 빔을 초점 스캔수신기 본드 패드 상에 도너 마이크로 범프를 전송하기위한 E. 270 엠제이 / cm 2의 플루 언스에서 수신기 본드 패드 위에 인듐 범프를 들어 올립니다 355 nm 파장과 12 PSEC 펄스 지속 시간의 피코 초 레이저 소스를 사용합니다. 참고 : 에너지와 같은 레이저 특성을, 아니. 펄스, 대물 렌즈의 높이, 인쇄 공여체 마이크로 범프 수신기 기판 정확하게 컴퓨터 프로그램에 의해 제어되는 전송 될 원하는 패턴에 정밀한 위치 조정한다. 중요한 실험 파라미터 (예, 전사 플루 언스)는 다른 레이저 광원을 사용하는 경우에 최적화 될 필요가있다. </li><li> 두꺼운 범프는 새로운 영역으로 기증자를 이동하고 단계를 1.1.4 여러 번 반복하십시오. 예를 들어,이 실험에서 서로의 상단에 인쇄 6 인듐 범프 스택을 얻는 단계 1.1.4에게 여섯 번 반복. 최종 범프 ~ 1.5 ㎛의 평균 높이의 20 μm의 (도 2)의 직경이 해제. 참고 : 이러한 experim 들어엔트 범프의 표면 프로파일 및 두께는 광학 프로파일로 미터를 사용하여 측정 하였다. (그림 3 노란색 표시로) 그것은 범프 1.5 μm의 평균 두께의 볼록 / 돔 형태를 가지고 있음을 확인 하였다, 범프의 직경에 대해 평균. 그 이유는 도너 레이저 조사 영역에서 용융 전사 후 펠릿 (인듐 저 융점) 수신기 표면에 도달하면 다시 고화 것에 기인한다고 생각된다. 이것의 장점은 VCSEL 접촉 패드에 프린트 범프의 양호한 접착 성을 초래한다는 것이다. </li></ol></li><li> 이 칩 열 압착하는 기판 (도 4-6) : <ol><li> 범프 기판에 광전자 칩을 접합하기위한 반자동 플립 칩 본더를 사용합니다. </li><li> 범프 형 수신기와 칩 본더의 각 진공 플레이트에 결합 될로드. 활성 영역 FAC으로, 즉, 대칭 위치에 칩을 놓습니다늦추십시오. </li><li> 적절한 픽업 도구를 사용하여 칩의 중심에 맞 춥니 다. 도 5에 도시 된 바와 같이 바늘 형상의 툴을 사용한다. 다음에,이 픽업 도구를 이용하여 칩을 선택한다. </li><li> 카메라 정렬 시스템을 이용하여 수신기 기판상의 대응 접촉 패드와 칩의 본드 패드를 정렬. </li><li> 일단 장소를 기판에 칩을 정렬. </li><li> 전기 및 기계 상호를 기판에 칩을 실현하는 동시에 열 (~ 200 ° C의)와 압력 (12.5 GF / 범프)를 적용합니다. </li></ol></li><li> 결합 어셈블리 (4-6도)의 캡슐화 : <ol><li> 주사기 바늘을 이용하여 접합 조립체의 가장자리 주위에 광학적으로 투명한 접착제를 디스펜스. 캡슐화는 결합 어셈블리의 기계적 신뢰성을 증가시킨다. 결합 칩을 캡슐화 NOA (86)과 같은 단일 성분 UV 경화형 접착제를 사용합니다. </li><li> ~ 30 초 동안 UV 램프를 이용하여 접착제를 경화. </li></ol></li></ol> 보세 수직 공동 표면 방출 레이저 2. 특성 (표면 광 레이저) 주 : 제작 한 후, 다음 단계는 접합 조립체의 전기 광학 성능을 평가하는 것이다. 소자의 광 전류 - 전압 (LIV) 곡선은 프로브 스테이션을 이용한 포스트 - 본딩 기록된다. 다음 단계는 테스트에 참여하고 있습니다 : <ol><li> 주문 제작 투명 무대에 장치를 결합 플립 칩을 놓습니다. 스테이지의 VCSEL에 의해 방사 된 광에 쉽게 액세스 할 수 있도록 중앙에 뚫린 구멍을 갖는다. </li><li> 투명 단계 아래의 광 검출기 (PD)를 놓고 현미경을 사용하여 결합 된 칩의 활성 영역을 맞 춥니 다. </li><li> 정확히 현미경을 사용하여 패드를 프로빙 니켈 - 금에 프로브 바늘을 놓습니다. </li><li> 전류 10mA까지 주입 한 VCSEL 양단의 전압 강하 및 전류 / 전압 소스 미터 유닛을 사용하여 출사 광 및 파워 미터 측정 입술에 각기. </li></ol>

<ol>
	<li>Davis, E., Harding, W., Schwartz, R., Coring, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solid+logic+technology:+versatile,+high+performance+microelectronics.">Solid logic technology: versatile, high performance microelectronics.</a> IBM J. Res. Develop. 8, 102-114 (1964).</li><li>Bigas, M., Cabruja, E., Lozano, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bonding+techniques+for+hybrid+active+pixel+sensors+(HAPS).">Bonding techniques for hybrid active pixel sensors (HAPS).</a> Nucl. Instrum. Methods Phys. Res. A. 574 (2), 392-400 (2007).</li><li>Bohandy, J., Kim, B. F., Adrian, F. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metal+deposition+from+a+supported+metal+film+using+an+excimer+laser.">Metal deposition from a supported metal film using an excimer laser.</a> J. Appl. Phys. 60 (4), 1538-1539 (1986).</li><li>Kaur, K. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shadowgraphic+studies+of+triazene+assisted+laser-induced+forward+transfer+of+ceramic+thin+films.">Shadowgraphic studies of triazene assisted laser-induced forward transfer of ceramic thin films.</a> J. Appl. Phys. 105 (11), 113119 (2009).</li><li>Boutopoulos, C., Pandis, C., Giannakopoulos, K., Pissis, P., Zergioti, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polymer/carbon+nanotube+composite+patterns+via+laser+induced+forward+transfer.">Polymer/carbon nanotube composite patterns via laser induced forward transfer.</a> Appl. Physc. Lett. 96, 041104 (2010).</li><li>Xu, J., Liu, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laser-assisted+forward+transfer+of+multi-spectral+nanocrystal+quantum+dot+emitters.">Laser-assisted forward transfer of multi-spectral nanocrystal quantum dot emitters.</a> Nanotechnology. 18 (2), 025403 (2007).</li><li>Doraiswamy, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Excimer+laser+forward+transfer+of+mammalian+cells+using+a+novel+triazene+absorbing+layer.">Excimer laser forward transfer of mammalian cells using a novel triazene absorbing layer.</a> Appl. Surf. Sci. 252 (13), 4743-4747 (2006).</li><li>Papazoglou, S., Raptis, Y. S., Chatzandroulis, S., Zergioti, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=I.A+study+on+the+pulsed+laser+printing+of+liquid+phase+exfoliated+graphene+for+organic+electronics.">I.A study on the pulsed laser printing of liquid phase exfoliated graphene for organic electronics.</a> Appl. Phys. A. , (2014).</li><li>Chatzipetrou, M., Tsekenis, G., Tsouti, V., Chatzandroulis, S., Zergioti, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biosensors+by+means+of+the+laser+induced+forward+transfer+technique.">Biosensors by means of the laser induced forward transfer technique.</a> Appl. Surf. Sci. 278, 250-254 (2013).</li><li>Stewart, J. S., Lippert, T., Nagel, M., Nuesch, F., Wokaun, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Red-green-blue+polymer+light-emitting+diode+pixels+printed+by+optimized+laser-induced+forward+transfer.">Red-green-blue polymer light-emitting diode pixels printed by optimized laser-induced forward transfer.</a> Appl. Phys. Lett. 100 (20), 203303 (2012).</li><li>Kaur, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Waveguide+mode+filters+fabricated+using+laser-induced+forward+transfer.">Waveguide mode filters fabricated using laser-induced forward transfer.</a> Opt. Express. 19 (10), 9814-9819 (2011).</li><li>Kuznetsov, A. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laser+fabrication+of+large-scale+nanoparticle+arrays+for+sensing+applications.">Laser fabrication of large-scale nanoparticle arrays for sensing applications.</a> ACS Nano. 5 (6), 4843-4849 (2011).</li><li>Rapp, L., Diallo, A. K., Alloncle, A. P., Videlot-Ackermann, C., Fages, F., Delaporte, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulsed-laser+printing+of+organic+thin-film+transistors.">Pulsed-laser printing of organic thin-film transistors.</a> Appl. Phys. Lett. 95 (17), 171109 (2009).</li><li>Bosman, E., Kaur, K. S., Missinne, J., Van Hoe, B., Van Steenberge, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assembly+of+optoelectronics+for+efficient+chip-to-waveguide+coupling.">Assembly of optoelectronics for efficient chip-to-waveguide coupling.</a> , 630-634 (2013).</li><li>Kaur, K. S., Missinne, J., Van Steenberge, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flip-chip+bonding+of+vertical-cavity+surface-emitting+lasers+using+laser-induced+forward+transfer.">Flip-chip bonding of vertical-cavity surface-emitting lasers using laser-induced forward transfer.</a> Appl. Phys. Lett. 104 (6), 061102 (2014).</li><li>Kaur, K. S., al, e. t. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laser-induced+forward+transfer+of+focussed+ion+beam+pre-machined+donors.">Laser-induced forward transfer of focussed ion beam pre-machined donors.</a> Appl. Surf. Sci. 257 (15), 6650-6653 (2011).</li></ol>

The authors have nothing to disclose.

본 논문에서는, 우리는 LIFT라는 레이저를 기반으로 직접 쓰기 기술을 사용하여 하나의 VCSEL 칩의 열 압축 플립 칩 본딩을 증명하고있다. LIFT 기술을 이용하여 기판 콘택트 패드 상에 인듐의 마이크로 범프의 인쇄 관련 조립체 제조 단계. 이 열 압착 플립 칩 범프 기판에 VCSEL 칩 본딩 마침내 캡슐화 하였다. LIFT 보조 결합 칩, 전기 광학적, 기계적 신뢰성 그들의 LIV 곡선을 측정?...

레이저 유발 순방향 전송 (LIFT)는 단일 - 단계 패턴 정의 및 미크론 및 서브 미크론 해상도와 물질 전달을위한 다용도의 직접 기록 첨가제의 제조 방법이다. 본 논문에서는, 우리는 칩 스케일에 수직 공동 표면 방출 레이저 (의 VCSEL)의 플립 칩 패키징에 대한 범핑 기술로 LIFT의 사용을보고합니다. 플립 칩은 시스템 패키징 및 전자 및 광전자 (OE) 구성 요소의 통합의 핵심 기술이다. 부품의 고밀도 통합을 달성하기 위해서, 파인 피치 접합이 필수적이다. 파인 피치 접합의 일부 표준 기술에 의해 증명되지만, 유연성, 경제성, 속도, 정확도 및 낮은 가공 온도로 다른 중요한 기능을 함께 결합하는면에서 보이드가되었지만. 이러한 요구 사항을 충족하기 위해, 우리는 OE 성분의 파인 피치 접합 용 LIFT 이용한 열 압착 접합 방법을 설명한다. L에서IFT (도너로 지칭) 인쇄 될 재료의 박막 (담체 라 함) 레이저 투명지지 기판의 한쪽면 상에 증착된다. (1)가이 기술의 기본적인 원리를 도시 한 도표. 충분한 강도의 입사 레이저 펄스는 다음 근접하여 배치 (수신자로 칭함) 또 다른 기판 상에 조사 된 영역의 도너 화소 전송 전달할 필요 추진 동력을 제공 사업자 도너 계면에 집중된다. LIFT 먼저 손상 포토 마스크 (3) 수리를 위해 미크론 크기의 구리 선을 인쇄하는 기술로 Bohandy에 의해 1986 년에보고되었다. 첫 데모 때문에이 기술은 세라믹 4, 탄소 나노 튜브 5, 6 양자점 등 다양한 재료의 패터닝을 제어 및 인쇄, 살아있는 세포 7 그래프 용 마이크로 - 나노 제작 기술에 상당한 관심을 얻고엔 8, 바이오 - 센서 (9), 유기 발광 다이오드 (10), 광전자 부품 (11), 플라즈몬 센서 (12), 유기 전자 (13)와 플립 칩 본딩 (14, 15) 등 다양한 애플리케이션을위한. LIFT는 OE 성분의 플립 칩 장착을위한 단순성, 속도, 유연성, 비용 효율성, 높은 해상도 및 정밀도 등의 기존의 플립 칩 범핑 및 접합 기술에 비해 여러 장점을 제공한다.

<table><tbody><tr><td>Laser source</td><td>3D MicroMac (3DMM)</td><td>2912-295</td><td></td></tr><tr><td>Photodetector</td><td>Newport&amp;nbsp;</td><td>818 series</td><td></td></tr><tr><td>Source measurement unit</td><td>Keithley&amp;nbsp;</td><td>2401</td><td></td></tr><tr><td>Power meter</td><td>Newport&amp;nbsp;</td><td>1930</td><td></td></tr><tr><td>Underfill</td><td>Norlands</td><td>NOA 86</td><td></td></tr><tr><td>UV lamp</td><td>Omnicure</td><td>Series 1000 UV</td><td></td></tr><tr><td>Probe station</td><td>Cascade Microtech</td><td>model 42</td><td></td></tr><tr><td>Flip-chip bonder</td><td>Dr. Tresky</td><td>T-320 X</td><td></td></tr></tbody></table>

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

플립 칩 (FC) 포장 마이크로 전자 산업에서 고성능, 소형화 및 울트라 고밀도 회로를 실​​현하기위한 핵심 기술이다. 이러한 방법에 칩 및 / 또는 기판은 범핑되고이 두 도전성 범프를 통해 결합된다. 많은 범핑 기술 개발이 집중적 1960 한 이러한 공판 인쇄, 스터드 범핑, 증발과 같은 무전 / 2 FC 전기 도금 기술의 도입으로 조사되었다. 이들 방법은 모두 한 고통이나 비용, 복잡한 처리 단계, 높은 가공 온도, 제조 시간 및 유연성의 가장 중요한 부족 등 해결해야 할 하나 이상의 단점 만든 것을 진행 불구. 본 논문은 레이저 유발 순방향 전송 (LIFT)라고도 간단하고 비용 효율적인 레이저 기반의 범프 형성 기술 3을 증명한다. LIFT 기법 범프를 다양한 재료를 사용하여 수 bRT의 유연성, 높은 속도와 정확도 단일 단계에서 인쇄 한 전자. 또한, LIFT는 초소형 회로를 제조하기위한 중요한 칩 스케일, 아래로 범핑과 결합 할 수 있습니다.

도 7은 다수의 플립 칩 본딩 VCSEL 칩 중 하나에서 기록되었다 LIV 전형적인 곡선을 나타낸다. 공급 업체에 측정 된 광 전력 사이 좋은 경기는 값이 결합 장치 포스트 결합을 성공적으로 기능을 표시 인용했다. 곡선도있어 우선 사후 캡슐화를 기록하고, 그 비교에 (도 7에 도시 된 바와 같이) 밀봉 더 칩의 기능에 영향을했다는 확인되지 않았다. 또한, 플립 칩 본딩의 VCSEL과 베...

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

우리는 광전자 부품의 플립 칩 실장 용 레이저 유발 순방향 전송 (LIFT) 기술의 사용을 입증한다. 이 방법은 간단하고 비용 효과적인 저온, 광전자 응용을위한 고밀도 회로를 실​​현하기위한 칩 크기에 당김 미세 피치 및 접착 용 빠르고 유연한 솔루션을 제공한다.

단일 다이스의 플립 칩 패키징을위한 레이저 유도 앞으로 전송

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

12.3K 조회수.  Ghent University-imec.  우리는 광전자 부품의 플립 칩 실장 용 레이저 유발 순방향 전송 (LIFT) 기술의 사용을 입증한다. 이 방법은 간단하고 비용 효과적인 저온, 광전자 응용을위한 고밀도 회로를 실​​현하기위한 칩 크기에 당김 미세 피치 및 접착 용 빠르고 유연한 솔루션을 제공한다. 

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

Lensless Fluorescent Microscopy on a Chip

On-chip lensless imaging in general aims to replace bulky lens-based optical microscopes with simpler and more compact designs, especially for high-throughput screening applications. This emerging technology platform has the potential to eliminate the need for bulky and/or costly optical components through the help of novel theories and digital reconstruction algorithms. Along the same lines, here we demonstrate an on-chip fluorescent microscopy modality that can achieve e.g., &lt;4&mu;m spatial resolution over an ultra-wide field-of-view (FOV) of &gt;0.6-8 cm2 without the use of any lenses, mechanical-scanning or thin-film based interference filters. In this technique, fluorescent excitation is achieved through a prism or hemispherical-glass interface illuminated by an incoherent source. After interacting with the entire object volume, this excitation light is rejected by total-internal-reflection (TIR) process that is occurring at the bottom of the sample micro-fluidic chip. The fluorescent emission from the excited objects is then collected by a fiber-optic faceplate or a taper and is delivered to an optoelectronic sensor array such as a charge-coupled-device (CCD). By using a compressive-sampling based decoding algorithm, the acquired lensfree raw fluorescent images of the sample can be rapidly processed to yield e.g., &lt;4&mu;m resolution over an FOV of &gt;0.6-8 cm2. Moreover, vertically stacked micro-channels that are separated by e.g., 50-100 &mu;m can also be successfully imaged using the same lensfree on-chip microscopy platform, which further increases the overall throughput of this modality. This compact on-chip fluorescent imaging platform, with a rapid compressive decoder behind it, could be rather valuable for high-throughput cytometry, rare-cell research and microarray-analysis.

A lensless on-chip fluorescent microscopy platform is demonstrated that can image fluorescent objects over an ultra-wide field-of-view of e.g., &#62;0.6-8 cm2 with &#60;4&#956;m resolution using a compressive sampling based decoding algorithm. Such a compact and wide-field fluorescent on-chip imaging modality could be valuable for high-throughput cytometry, rare-cell research and microarray-analysis.

칩에 Lensless 형광 현미경

On-chip lensless imaging in general aims to replace bulky lens-based optical microscopes with simpler and more compact designs, especially for ...

연구

생체공학

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.

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

공학

Using Synchrotron Radiation Microtomography to Investigate Multi-scale Three-dimensional Microelectronic Packages

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data acquisition times with high spatial resolution. In the electronics industry there is serious interest in performing failure analysis on 3D microelectronic packages, many which contain multiple levels of high-density interconnections. Often in tomography there is a trade-off between image resolution and the volume of a sample that can be imaged. This inverse relationship limits the usefulness of conventional computed tomography (CT) systems since a microelectronic package is often large in cross sectional area 100-3,600 mm2, but has important features on the micron scale. The micro-tomography beamline at the Advanced Light Source (ALS), in Berkeley, CA USA, has a setup which is adaptable and can be tailored to a sample&#39;s properties, i.e., density, thickness, etc., with a maximum allowable cross-section of 36 x 36 mm. This setup also has the option of being either monochromatic in the energy range ~7-43 keV or operating with maximum flux in white light mode using a polychromatic beam. Presented here are details of the experimental steps taken to image an entire 16 x 16 mm system within a package, in order to obtain 3D images of the system with a spatial resolution of 8.7 &#181;m all within a scan time of less than 3 min. Also shown are results from packages scanned in different orientations and a sectioned package for higher resolution imaging. In contrast a conventional CT system would take hours to record data with potentially poorer resolution. Indeed, the ratio of field-of-view to throughput time is much higher when using the synchrotron radiation tomography setup. The description below of the experimental setup can be implemented and adapted for use with many other multi-materials.

For this study synchrotron radiation micro-tomography, a non-destructive three-dimensional imaging technique, is employed to investigate an entire microelectronic package with a cross-sectional area of 16 x 16 mm. Due to the synchrotron&#39;s high flux and brightness the sample was imaged in just 3 min&#160;with an 8.7 &#181;m spatial resolution.

멀티 스케일 3 차원 마이크로 전자 패키지를 조사하는 방사광 Microtomography 사용

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data ...

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.

의 Ag Nanopaste의 레이저 유도 앞으로 전송

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

Plasmonic Trapping and Release of Nanoparticles in a Monitoring Environment

Plasmonic tweezers use surface plasmon polaritons to confine polarizable nanoscale objects. Among the various designs of plasmonic tweezers, only a few can observe immobilized particles. Moreover, a limited number of studies have experimentally measured the exertable forces on the particles. The designs can be classified as the protruding nanodisk type or the suppressed nanohole type. For the latter, microscopic observation is extremely challenging. In this paper, a new plasmonic tweezer system is introduced to monitor particles, both in directions parallel and orthogonal to the symmetric axis of a plasmonic nanohole structure. This feature enables us to observe the movement of each particle near the rim of the nanohole. Furthermore, we can quantitatively estimate the maximal trapping forces using a new fluidic channel.

A microchip fabrication process that incorporates plasmonic tweezers is presented here. The microchip enables the imaging of a trapped particle to measure maximal trapping forces.

모니터링 환경에서 플라즈몬 트랩 및 나노 입자의 릴리스

Plasmonic tweezers use surface plasmon polaritons to confine polarizable nanoscale objects. Among the various designs of plasmonic tweezers, only a few ...

Multicolor Fluorescence Detection for Droplet Microfluidics Using Optical Fibers

Fluorescence assays are the most common readouts used in droplet microfluidics due to their bright signals and fast time response. Applications such as multiplex assays, enzyme evolution, and molecular biology enhanced cell sorting require the detection of two or more colors of fluorescence. Standard multicolor detection systems that couple free space lasers to epifluorescence microscopes are bulky, expensive, and difficult to maintain. In this paper, we describe a scheme to perform multicolor detection by exciting discrete regions of a microfluidic channel with lasers coupled to optical fibers. Emitted light is collected by an optical fiber coupled to a single photodetector. Because the excitation occurs at different spatial locations, the identity of emitted light can be encoded as a temporal shift, eliminating the need for more complicated light filtering schemes. The system has been used to detect droplet populations containing four unique combinations of dyes and to detect sub-nanomolar concentrations of fluorescein.

Multicolor fluorescence detection in droplet microfluidics typically involves bulky and complex epifluorescence microscope-based detection systems. Here we describe a compact and modular multicolor detection scheme that utilizes an array of optical fibers to temporally encode multicolor data collected by a single photodetector.

물방울 미세 유체에 대한 여러 가지 빛깔의 형광 검출 광학 섬유를 사용하여

Fluorescence assays are the most common readouts used in droplet microfluidics due to their bright signals and fast time response. Applications such as ...

Automated Delivery of Microfabricated Targets for Intense Laser Irradiation Experiments

Described is an experimental procedure that enables high-power laser irradiation of microfabricated targets. Targets are brought to the laser focus by a closed feedback loop that operates between the target manipulator and a ranging sensor. The target fabrication process is explained in detail. Representative results of MeV-level proton beams generated by irradiation of 600 nm thick gold foils at a rate of 0.2 Hz are given. The method is compared with other replenishable target systems and the prospects of increasing the shot rates to above 10 Hz are discussed.

A protocol is presented for automated irradiation of thin gold foils with high intensity laser pulses. The protocol includes a step-by-step description of the micromachining target fabrication process and a detailed guide for how targets are brought to the laser&#39;s focus at a rate of 0.2 Hz.

강렬한 레이저 조사 실험을 위한 미세 가공 대상의 자동 전달

Described is an experimental procedure that enables high-power laser irradiation of microfabricated targets. Targets are brought to the laser focus by a ...

Multi-step Variable Height Photolithography for Valved Multilayer Microfluidic Devices

Microfluidic systems have enabled powerful new approaches to high-throughput biochemical and biological analysis. However, there remains a barrier to entry for non-specialists who would benefit greatly from the ability to develop their own microfluidic devices to address research questions. Particularly lacking has been the open dissemination of protocols related to photolithography, a key step in the development of a replica mold for the manufacture of polydimethylsiloxane (PDMS) devices. While the fabrication of single height silicon masters has been explored extensively in literature, fabrication steps for more complicated photolithography features necessary for many interesting device functionalities (such as feature rounding to make valve structures, multi-height single-mold patterning, or high aspect ratio definition) are often not explicitly outlined. 
Here, we provide a complete protocol for making multilayer microfluidic devices with valves and complex multi-height geometries, tunable for any application. These fabrication procedures are presented in the context of a microfluidic hydrogel bead synthesizer and demonstrate the production of droplets containing polyethylene glycol (PEG diacrylate) and a photoinitiator that can be polymerized into solid beads. This protocol and accompanying discussion provide a foundation of design principles and fabrication methods that enables development of a wide variety of microfluidic devices. The details included here should allow non-specialists to design and fabricate novel devices, thereby bringing a host of recently developed technologies to their most exciting applications in biological laboratories.

Multilayer microfluidic devices often involve the fabrication of master molds with complex geometries for functionality. This article presents a complete protocol for multi-step photolithography with valves and variable height features tunable to any application. As a demonstration, we fabricate a microfluidic droplet generator capable of producing hydrogel beads.

판막 다층 미세 유체 장치에 대한 여러 단계의 변수 높이 포토 리소그래피

Microfluidic systems have enabled powerful new approaches to high-throughput biochemical and biological analysis. However, there remains a barrier to ...

High-resolution Volume Imaging of Neurons by the Use of Fluorescence eXclusion Method and Dedicated Microfluidic Devices

Volume is an important parameter regarding physiological and pathological characteristics of neurons at different time scales. Neurons are quite unique cells regarding their extended ramified morphologies and consequently raise several methodological challenges for volume measurement. In the particular case of in vitro neuronal growth, the chosen methodology should include sub-micrometric axial resolution combined with full-field observation on time scales from minutes to hours or days. Unlike other methods like cell shape reconstruction using confocal imaging, electrically-based measurements or Atomic Force Microscopy, the recently developed Fluorescence eXclusion method (FXm) has the potential to fulfill these challenges. However, although being simple in its principle, implementation of a high-resolution FXm for neurons requires multiple adjustments and a dedicated methodology. We present here a method based on the combination of fluorescence exclusion, low-roughness multi-compartments microfluidic devices, and finally micropatterning to achieve in vitro measurements of local neuronal volume. The high resolution provided by the device allowed us to measure the local volume of neuronal processes (neurites) and the volume of some specific structures involved in neuronal growth, such as growth cones (GCs).

Volume is an important parameter regarding physiological and pathological characteristics of cells. We describe a fluorescent exclusion method allowing full-field measurement of in vitro neuronal volume with sub-micrometric axial resolution required for the analysis of neurites and dynamic structures implied in neuronal growth.

고해상도 볼륨 이미징의 뉴런 형광의 사용 제외 방법에 의해 및 미세 장치 전용

Volume is an important parameter regarding physiological and pathological characteristics of neurons at different time scales. Neurons are quite unique ...

신경과학

Microfabrication of Implantable Optics Integrated in a Microstructured Imaging Window for Advanced In Vivo Imaging

In the context of biomaterials and drug testing in animal models, this study presents a streamlined protocol for fabricating a novel implantable integrated imaging window. The micro-device comprises a sophisticated system of microlenses coupled with micro-scaffolds specifically designed for in vivo quantification of the immune response using advanced non-linear excitation microscopy. The protocol is based on two-photon polymerization (2PP) of the biocompatible photoresist SZ2080, which enables the fabrication of micro-scaffolds and micro-lenses in a continuous sequence to enhance manufacturing efficiency and precision. To further improve speed, accuracy, and structural integrity, a hybrid optics fabrication approach was implemented, involving the 2PP of the microlens outer shell followed by UV bulk crosslinking of the inner core. This innovative technique optimizes the optical properties of the microlenses while streamlining the production process. The resulting micro-device demonstrates high reproducibility and mechanical stability, making it an effective method for prototyping microscale optical systems for a range of biomedical applications.

This protocol describes the fabrication of an implantable integrated imaging window using 3D laser printing. The window consists of a system of microlenses coupled with micro-scaffolds. The method involves two-photon polymerization (2PP) of the biocompatible photoresist SZ2080 in a continuous sequence, optimizing manufacturing efficiency and alignment between the different components.