Part of the work has been performed in the project JEMSiP_3D, which is funded by the Public Authorities in France, Germany, Hungary, The Netherlands, Norway and Sweden, as well as by the ENIAC Joint Undertaking. The authors would like to thank the Dimes Technology Centre staff for processing support.

주의 : 사용하기 전에 모든 관련 물질 안전 보건 자료 (MSDS)를 참조하시기 바랍니다. 이 제조 공정에서 사용되는 화학 물질 중 일부는 급성 독성 및 발암 성이다. 나노 물질은 대량의 대응에 비해 추가 위험이있을 수 있습니다. 공학적 관리 (흄 후드) 및 개인 보호 장비 (안전 안경, 장갑, 클린 룸 의류)의 사용을 포함, 장비, 화학 물질이나 나노 물질 작업을 할 때 모든 적절한 안전 방법을 사용하십시오. 리소그래피 1. 정렬 마커 정의 <ol><li> 하나 n 또는 p 형 도핑 단일 양면 연마 산업 등급의 Si (100) 웨이퍼로 시작합니다. </li><li> 코트 긍정적 인 포토 레지스트의 1.4 μm의와 웨이퍼. 적절한 속도 (3500 RPM)에서 냉각 판, 스핀 코팅에 웨이퍼를 냉각 한 다음, 포토 레지스트의 접착을 촉진하기 위해 130 ℃에서 90 초, 헥사 메틸 디 실라 잔 (HMDS) 처리를 수행하고, 90 초간 소프트 베이크T 95 ° C를. </li><li> 포토 리소그래피 마스크를 사용하여 노광 툴은 정렬 마커를 노출, 노광량 120 mJ의 / cm 2. </li><li> 하나의 웅덩이 개발 프로세스를 수행합니다. 레지스트가 경화 100 ℃에서 90 초간 현상하고 하드 베이크를 사용하여 60 초간 현상 한 다음 90 초 115 ° C의 노광 후 베이킹을 수행. </li><li> 레지스트의 개구부가 정확한 치수의 경우 검사 현미경을 사용합니다. </li><li> Si를 염소 플라즈마 에칭을 사용하여 120 nm의 에칭. 이 두께는이 작품에 사용되는 노광 장치의 자동 정렬 시스템을위한 좋은 대조를 제공합니다. 20/40 SCCM의 O 2 / CF 4, 5 mTorr 이하, 정반 500분의 60 W / ICP RF 전력, Cl2를 40분의 80 SCCM이어서 10 초 산화물 브레이크 스루 에칭 / HBr을 : 유도 결합 형 플라즈마 (ICP)를 사용하여 예를 들어 , 60 mTorr 이하, 5백분의 20 W 정반 / ICP RF 전력, 35 초 Si의 에칭. </li><li> 포토 레지스트 (1 kW 급, endpo 400 SCCM의 O 2를 제거하기 위해 산소 플라즈마 스트리퍼를 사용하여INT 검출 및 2 분 오버 에칭). 포토 레지스트는 아세톤과 같은 플라즈마 통상 용매에 의해 경화되기 때문에 사용될 수 없다. </li><li> 웨이퍼를 청소합니다. 물의 저항은 5 MΩ (유기 청소) 될 때까지 첫 번째 DI 물에 세척 한 다음 99 % HNO 3, 10 분 동안 넣어. 물의 비저항은 5 MΩ (깨끗한 금속) 될 때까지 110 ℃에서 65 % HNO 3에서 10 분간 웨이퍼이 깨끗하게 한 후, 탈 이온수로 린스 하였다. 웨이퍼를 건조 린서 드라이어를 사용합니다. </li></ol> 2. 아래 금속 및 층간 증착 <ol><li> 비아 시험 하부 금속층을 증착하기 위해 마그네트론 스퍼터링을 사용한다. Ti를 500nm의 주석을 50 nm의, 100 nm의 티를 세 금속층 스택에 증착 될 필요가있다. 제 Ti 층 스택의 저항을 감소시키는, 주석은 CNT 성장 실제 지지층이며, SiO2의 층 (12)을 에칭 할 때 상단 TI는 플라즈마 손상에 대해 주석 보호하는 </suP&gt;. TI는 350 ℃의 기판 온도에서 아르곤 플라즈마과 순수한 티타늄의 타겟을 이용하여 스퍼터링을 수행한다. 반응성 스퍼터링 TiN을 350 ℃의 기판 온도에서 다시, 아르곤 및 N (2)의 조합을 사용한다. </li><li> 플라즈마 강화 화학 기상 증착 (PECVD)을 이용하여, SiO2로 1 μm의 두께 층을 증착. 여기에 테트라 에틸 오르토 실리케이트 (TEOS)를 350 ℃의 온도에서 압반 전구체로서 사용된다. <ol><li> 적절한 도구를 사용하여 SiO2로 층의 두께, 예를 들어 반사 또는 엘 립소 미터를 확인한다. </li></ol></li><li> 코트 적절한 속도 (3500 RPM)에서 냉각 판, 스핀 코팅에 웨이퍼를 냉각 한 다음 130 ℃에서 90 초 HMDS 처리, 시작하여 포지티브 형 포토 레지스트의 1.4 μm의 가진 웨이퍼, 촉감 90 초 95 ℃에서 굽는다. </li><li> 포토 리소그래피 마스크 및 노광 툴을 사용하여, 나중에 그런가 2t 안으로 에칭 될 개구부의 원하는 패턴을, 노광O 정렬 마커에 정렬 비아를 형성하고, 노광량 140 mJ의 / cm 2. </li><li> 100 ℃에서 90 초간 현상 및 하드 베이크를 사용하여 60 초간 현상 한 다음 90 초 115 ° C의 노광 후 베이크로 시작하는 하나의 퍼들 현상 공정을 수행한다. </li><li> 레지스트의 개구부가 올바른 치수 및 정렬 마커에 오버레이가 올바른지 경우 검사 현미경을 사용합니다. </li><li> 플라즈마에 SiO2로 접촉 개구를 에칭. 예를 들어, C 2 F 6 단자 플라즈마 에칭을 사용 / CHF 3 1백44분의 36 SCCM 180 mTorr 내지 300 W의 RF 전력에서. 필요한 경우, 시간의 5 % -10 %의 오버 에칭 최소화하기 위해 테스트 웨이퍼에 대한 식각 율 테스트를 수행. 주 : TI는이 불소 화학 반응성 에칭에 저항하지만, 플라즈마에 장기간 노출 티 층의 물리적 에칭 발생합니다. TiN 층이 플라즈마에 노출되면이 부정적인 influen이있을 것이다CNT (12)의 성장에 CE. 이 구멍을 너무 많이 확대 될 것으로 제 4 부 문제에서 최고의 금속을, 습식 에칭을 사용하지 마십시오. </li><li> 60 초 동안 0.55 %의 HF 습식 에칭에 의해 희생 Ti 층을 제거합니다. 물 저항률까지 DI 물 린스 웨이퍼 에칭 후 5 MΩ이고 웨이퍼를 건조 린서 건조기를 사용한다. 주 : TI는 금속성 회색 인 반면, Ti 층을 에칭하는 경우는, 점검 할 수 현미경을 사용하여, TiN 층은 금 갈색을 가질 것이다. </li></ol> 3. 촉매 증착 및 탄소 나노 튜브 성장 <ol><li> 전자빔 증착기를 이용하여 5 nm의 공동을 증발시켰다. 적어도 2 × 10 -6 Torr로 펌핑 다운 될 때까지, 임의의 수막을 제거하기 위해 증착 전에 진공 하에서 램프를 사용하여 60 ° C로 웨이퍼를 가열한다. 포토 레지스트 접촉 개구를 정의하는 데 사용은 SiO2로에 접촉 개구에 촉매의 자기 정렬을 제공하기 위해 웨이퍼 상에 유지된다. </li><li> 풀다리프트 오프 (lift-off)에 의해 접촉 구멍 외부 공동. 공동 들어 그것은 테트라 하이드로 퓨란 (THF)이 낮은 온도에서 최적의 리프트 오프 결과와 성장을 제공 한 것으로 밝혀졌습니다. 이전 철 증발 후 리프트 오프 (lift-off)에 사용 된 N 개의 메틸 -2- 피 롤리 돈 (NMP)이, 손상 발견 공동 너무 정도로 모든 정렬 CNT의 성장을 방지 할 수있다. 35 ℃에서 THF와 초음파 조에서 15 분 동안 웨이퍼를 넣습니다. 5 분 동안 탈 이온수로 씻어 스피너 또는 질소 총을 사용하여 건조. </li><li> 현미경 아래에 웨이퍼를 검사하고 잔류 물에 저항을 확인합니다. 잔류 수동 잔류 물을 닦아 리프트 오프 (lift-off) 목적을위한 특별한 부드러운 면봉을 사용하여 선택적으로 THF에 이상 초음파 처리를 수행하고, 남아있는 경우. </li><li> 저압 화학 기상 증착 (LPCVD)을 이용하여 CNT의 성장을 수행한다. 50 SCCM의 C 2 H 2를 추가하여 탄소 나노 튜브 성장에 이어 80 밀리바에서 700 SCCM H 2로 350 ℃에서 8 분 전 어닐링 : 다음과 같은 조리법을 사용합니다. 350 ° C에서, (60)성장의 분은 약 1 μm의 탄소 나노 튜브의를 제공합니다. 필요하면 조정하는 시험을 성장의 SiO2 층과 동일한 두께이어야 높이를 수행한다. 원자로를 냉각 및 N 2를 사용하여 제거. </li><li> 또는 단면을 준비하여 45 ° 경사 아래 개구 내부 CNT의 높이를 검사하는 주사 전자 현미경을 사용한다. </li><li> CNT (18)의 결정 성을 결정하는 라만 분광법을 이용하여 시료를 검사한다. </li></ol> 4. 톱 사이드 금속 화 <ol><li> 최고 금속을 증착 마그네트론 스퍼터링을 사용합니다. TI는 CNT (19)와 접촉하기위한 양호한 금속이므로, 먼저 진공을 깨지 않고 알 (1 %의 Si) 2 ㎛의 Ti를이어서 100 nm의 스퍼터. </li><li> 코팅 3,000 rpm에서 콜드 플레이트, 스핀 코팅에 웨이퍼를 냉각 한 다음 130 ℃에서 90 초 HMDS 처리로 시작 높은 점도와 포지티브 형 포토 레지스트의 3.1 μm의, 및 90 초간 소프트 베이크시와 웨이퍼 (95)기음. </li><li> 포토 리소그래피 마스크 및 노광 툴을 사용하여 정렬 마커에 정렬 상부 금속 패턴, 노광량 420 mJ의 / cm 2, -1의 초점을 노출. </li><li> 하나의 웅덩이 개발 프로세스를 수행합니다. 이것은 100 ℃에서 개발자 90 초 하드 베이크를 사용하여 60 초 개발 한 다음, 90 초 115 ° C의 노출 후 베이킹을 시작합니다. </li><li> 레지스트의 라인이 올바른 치수 및 마커 오버레이가 올바른지 경우 검사 현미경을 사용합니다. </li><li> 염소 플라즈마 에칭을 이용하여 티타늄 / 알루미늄 스택을 에칭. 유도 결합 형 플라즈마를 사용하는 예를 들어 : 30/40 SCCM CL 2 / HBr을, 5 mTorr 이하, 종말점 검출하고, 80 %의 오버 에칭으로 압반 5백분의 40 W / ICP RF 전력은 15/30 SCCM CL 2 / HBr로를 사용. </li><li> 포토 레지스트 (1 킬로와트, 종말점 검출하고 2 분 과식 400 SCCM의 O 2)를 제거하기 위해 산소 플라즈마를 사용하여 스트리퍼. 금속 따르면이 완료되지 않은 경우 (즉, 핀홀 주위에 존재CNT)는 CNT에 플라즈마 손상을 방지하기 위해 포토 레지스트를 제거하기 위해, 유기 용매 (예를 들면, NMP)을 사용한다. </li><li> 웨이퍼를 청소합니다. 물의 비저항은 5 MΩ (유기 청소) 될 때까지 탈 이온수로 세척 한 다음 99 % HNO 3, 10 분 동안 넣어. 웨이퍼를 건조 린서 드라이어를 사용합니다. </li></ol> 5. 측정 <ol><li> 웨이퍼의 상부 금속 화를 확인하기 위해 제조업 자의 지시에 따라 주 사형 전자 현미경을 사용한다. 주 :.도 3에 도시 된 바와 같이, 웨이퍼는 기계적 이미지 결과 90 ° 샘플 기울기를 사용을 통해 완전한 CNT를 확인하기 위해서 절단 될 수있는 필요하다면 시료를 도전대로 추가적인 처리 단계를 사용하지 않는 것으로하고 샘플은 직접 SEM에 장착 될 수있다. 일반적으로, 15 또는 20 kV의 높은 가속 전압이 사용될 수 있지만, 경우의 SiO2 층이 너무 많이 감소시킬 수 t를 충전되고5 kV의를 오. </li><li> 4- 포인트를 수행하고도 1에 Vollebregt 외. (16)에 기재된 반도체 파라미터 분석기와 결합 프로브 스테이션을 사용하여 프로브 IV 측정. 참고 : 상호 연결을 통해 잠재적 인 드롭이 이상적으로 작은로서 일반적으로 -0.5 V 0.5에서 전압 스윕은 충분하다. 4- 포인트 프로브 설정을 이용하여 프로브 침과 설치의 와이어 저항의 접촉 저항을 생략한다. </li></ol>

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Eng. 64 (1-4), 399-408 (2002).</li><li>Vereecke, B., 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=Characterization+of+carbon+nanotube+based+vertical+interconnects.">Characterization of carbon nanotube based vertical interconnects.</a> Extended Abstracts of the 2012 International Conference on Solid State Devices and Materials. , 648-649 (2012).</li><li>Vollebregt, S., Ishihara, R., Derakhshandeh, J., vander Cingel, J., Schellevis, H., Beenakker, C. I. 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H., 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=Electrical+Improvement+of+CNT+Contacts+with+Cu+Damascene+Top+Metallization.">Electrical Improvement of CNT Contacts with Cu Damascene Top Metallization.</a> Proceedings of the IEEE International Interconnect Technology Conference. , 193-195 (2013).</li><li>Istratov, A. A., Hieslmair, H., Weber, E. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Iron+contamination+in+silicon+technology.">Iron contamination in silicon technology.</a> Appl. Phys. A. 70, 489-534 (2000).</li><li>Vollebregt, S., Tichelaar, F. D., Schellevis, H., Beenakker, C. I. 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Lett. 95 (26), 264103 (2009).</li><li>Awano, Y., 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=Carbon+nanotube+via+interconnect+technologies:+size-classified+catalyst+nanoparticles+and+low-resistance+ohmic+contact+formation.">Carbon nanotube via interconnect technologies: size-classified catalyst nanoparticles and low-resistance ohmic contact formation.</a> Phys. Status Solidi (a). 203 (14), 3611-3616 (2006).</li><li>Van der Veen, M. H., 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=Electrical+characterization+of+CNT+contacts+with+Cu+Damascene+top+contact.">Electrical characterization of CNT contacts with Cu Damascene top contact.</a> Microelectron. Eng. 106, 106-111 (2012).</li><li>Horibe, M., Nihei, M., Kondo, D., Kawabata, A., Awano, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+Polishing+Technique+for+Carbon+Nanotube+Interconnects+in+ULSIs.">Mechanical Polishing Technique for Carbon Nanotube Interconnects in ULSIs.</a> Jpn J. App. Phys. 43 (9A), 6499-6502 (2004).</li><li>Vollebregt, S., Chiaramonti, A. N., Ishihara, R., Schellevis, H., Beenakker, C. I. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contact+resistance+of+low-temperature+carbon+nanotube+vertical+interconnects.">Contact resistance of low-temperature carbon nanotube vertical interconnects.</a> Proceedings of the 12th IEEE Conference on Nanotechnology. , 424-428 (2012).</li><li>Fiorentino, G., Vollebregt, S., Tichelaar, F. D., Ishihara, R., Sarro, P. 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The authors have nothing to disclose.

도 1은 본 연구에서 제작 한 구조물의 개략도를 표시하고, 이는 4 점 탐침 측정에 사용 하였다. 전위가 전류를 운반하지 프로브에 의해 측정 된 바와 같이, 중앙 CNT 다발과 금속과의 접촉을 통해 정확한 전위 강하 (V H 종의 -V L)를 측정 할 수있다. 더 큰 직경의 CNT 번들 강제 전류 프로브의 전체 저항을 감소시키고 중앙 CNT 다발 위에 전위 강하를 최대화하기 위해, 접촉 ?...

구리, 텅스텐, 현재 최첨단 매우-대규모 통합 (VLSI) 기술의 상호 연결에 사용되는 금속은 안정성과 전기 전도성 1의 관점에서 물리적 한계에 접근하고있다. 다운 스케일링 트랜지스터는 일반적으로 그들의 성능이 향상되지만, 실제로 저항 및 배선의 전류 밀도를 증가시킨다. 이것은 지연 및 전력 소비의 측면에서 2 집적 회로 (IC)의 성능을 지배 상호 결과. 탄소 나노 튜브 (CNT)는 수직 상호 탄소 나노 튜브로 (비아) 쉽게 3 수직 성장하고 있습니다 특히 위해, Cu 및 W 금속에 대한 대안으로 제안되었다. CNT는 Cu를 4보다 1000 배 더 높은 전류 밀도를 최대 허용 우수한 전기적 안정성을 보여왔다. 또한, CNT가 표면 및 입자 경계 산란 겪지 않으며, 이는 R을 증가나노 미터 스케일 (5)에서 구리의 esistivity. 마지막으로, CNT는 VLSI 칩의 열 관리에 도움이 될 수있다 우수한 열 전도체 (6) 인 것으로 밝혀졌다. VLSI 기술에 대한 CNT의 성공적인 통합 것이 대한 CNT 성장 프로세스가 반도체 제조 양립하는 것이 중요하다. 이는 물질 및 대규모 제조에 호환 및 확장 장치를 고려하여 CNT (&lt;400 °의 C)의 저온 성장을 필요로한다. CNT 시험 비아의 많은 예들은 7,8,9,10,11,12,13,14 문헌에서 설명되었지만, 이들의 대부분은 오염 물질의 IC (15)를 제조하는 것으로 간주되는 철을 촉매로 사용한다. 게다가, 이러한 많은 작품에서 사용되는 성장 온도가 400 ° C의 상한보다 훨씬 높다. 바람직 CNT도 현대 저 κ 유전체 또는가요 성 통합을 허용하기 위해, 350 ° C 이하로 성장되어야기판. 여기에서 우리는 촉매 (16)로 공동을 사용하여 350 ℃의 낮은 온도에서 탄소 나노 튜브를 성장을위한 확장 가능한 방법을 제시한다. 이 방법은, 집적 회로에서 수직 배향 CNT 이루어진 다른 전기적 구조들을 제조하는 수퍼 커패시터 및 전계 방출 소자로 상호 연결 전극 이르기위한 관심사이다. 주석은 종종 사용 차단재 7 동안 공동 촉매 금속은 종종 실리사이드의 (17)의 제조를 위해 IC 제조에서 사용된다. 더욱이, 우리는 표준 반도체 제조 기술에서 사용 중에 CNT 시험 비아를 제조하기위한 프로세스를 보여준다. 이에 의해, CNT 시험 비아 전자 현미경 (SEM) 및 라만 분광법, 전기적 특성화를 스캔하여 검사, 제조된다.

<table border="0" cellpadding="0" cellspacing="0" width="905">
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		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Materials</td>
			<td style="width:188px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:291px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Si (100) wafer 4&#34;</td>
			<td style="width:188px;">International Wafer Service</td>
			<td style="width:119px;"></td>
			<td>Resisitivity: 2-5 m&#937;-cm, thickness: 525 &#181;m&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Ti-sputtertarget (99.995 % purity)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Al (1% Si)-sputtertarget (99.999 % purity)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Co (99.95 % purity)</td>
			<td style="width:188px;">Kurt J. Lesker</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Chemicals</td>
			<td style="width:188px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td>Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">SPR3012 positive photoresist</td>
			<td style="width:188px;">Dow Electronic Materials</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">MF-322 developer</td>
			<td style="width:188px;">Dow Electronic Materials</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">HNO3 (99.9 %)</td>
			<td style="width:188px;">KMG Ultra Pure Chemicals</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">HNO3 (69.5%)</td>
			<td style="width:188px;">KMG Ultra Pure Chemicals</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">HF 0.55%</td>
			<td style="width:188px;">Honeywell</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Tetrahydrofuran</td>
			<td style="width:188px;">JT Baker</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Acetone</td>
			<td style="width:188px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">ECI3027 positive photoresist</td>
			<td style="width:188px;">AZ</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Tetraethyl orthosilicate (TEOS)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Gasses</td>
			<td style="width:188px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td>Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">N2 (99.9990%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">O2 (99.9999%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">CF4 (99.9970%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">CL2 (99.9900%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">HBr (99.9950%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Ar (99.9990%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">C2F6 (99.9990%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">CHF3 (99.9950%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">H2 (99.9950%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">C2H2 (99.6000%)</td>
			<td style="width:188px;">Praxair</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Equipment</td>
			<td style="width:188px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td>Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">EVG 120 coater/developer</td>
			<td style="width:188px;">EVG</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">ASML PAS5500/80 waferstepper</td>
			<td style="width:188px;">ASML</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">SPTS &#937;mega 201 plasma etcher</td>
			<td style="width:188px;">SPTS</td>
			<td style="width:119px;"></td>
			<td>Used for Si and metal etching</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">SPTS &#931;igma sputter coater</td>
			<td style="width:188px;">SPTS</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Novellus Concept One PECVD</td>
			<td style="width:188px;">LAM</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Drytek 384T plasma etcher</td>
			<td style="width:188px;">LAM</td>
			<td style="width:119px;"></td>
			<td>Used for oxide etching</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">CHA Solution e-beam evaporator</td>
			<td style="width:188px;">CHA</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">AIXTRON BlackMagic Pro CVD tool</td>
			<td style="width:188px;">AIXTRON</td>
			<td style="width:119px;"></td>
			<td>Carbon nanotube growth</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Philips XL50 scanning electron microscope</td>
			<td style="width:188px;">FEI</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Tepla 300</td>
			<td style="width:188px;">PVA TePla</td>
			<td style="width:119px;"></td>
			<td>Resist plasma stripper</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Avenger rinser dryer</td>
			<td style="width:188px;">Microporcess Technologies</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Leitz MPV-SP reflecometer</td>
			<td style="width:188px;">Leitz</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Renishaw inVia Raman spectroscope</td>
			<td style="width:188px;">Renishaw</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Agilent 4156C parameter spectrum analyzer</td>
			<td style="width:188px;">Agilent</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:307px;">Cascade Microtech probe station</td>
			<td style="width:188px;">Cascade Microtech</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

fabrication of low temperature carbon nanotube vertical interconnects compatible with semiconductor technology

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive thin-films. Due to the low growth temperature, the process allows integration with modern low-&#954; dielectrics and some flexible substrates. The process is compatible with standard semiconductor fabrication, and a method for the fabrication of electrical 4-point probe test structures for vertical interconnect test structures is presented. Using scanning electron microscopy the morphology of the CNT bundles is investigated, which demonstrates vertical alignment of the CNT and can be used to tune the CNT growth time. With Raman spectroscopy the crystallinity of the CNT is investigated. It was found that the CNT have many defects, due to the low growth temperature. The electrical current-voltage measurements of the test vertical interconnects displays a linear response, indicating good ohmic contact was achieved between the CNT bundle and the top and bottom metal electrodes. The obtained resistivities of the CNT bundle are among the average values in the literature, while a record-low CNT growth temperature was used.

이 연구에서 사용 된 측정 구조의 설계는도 1에서 발견 될 수있다. 탐침 및 와이어 저항을 회피 한, CNT 다발 저항과 금속 CNT의 접촉 저항의 측정이 정확하게 판정 될 수있는 구조를 채용함으로써. 다발의 저항은 CNT 다발의 품질과 밀도를 측정한다. 상이한 길이의 접촉 저항 번들을 결정하기 위하여 측정한다. 45 ° 기울기에서 금속 화 전에 위쪽에서 찍은 60 분 동안...

Watch this Scientific Journal Video about Fabrication of Low Temperature Carbon Nanotube Vertical Interconnects Compatible with Semiconductor Technology at JoVE.com

Fabrication of Low Temperature Carbon Nanotube Vertical Interconnects Compatible with Semiconductor Technology

A method for the growth of low temperature vertically-aligned carbon nanotubes, and the subsequent fabrication of vertical interconnect electrical test structures using semiconductor fabrication is presented.

반도체 기술과 호환 저온 탄소 나노 튜브 수직 상호 연결의 제작

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive ...

fabrication-low-temperature-carbon-nanotube-vertical-interconnects

Research

JoVE Journal

Engineering

7.6K 조회수.  Delft University of Technology. A method for the growth of low temperature vertically-aligned carbon nanotubes, and the subsequent fabrication of vertical interconnect electrical test structures using semiconductor fabrication is presented.

비디오: Fabrication of Low Temperature Carbon Nanotube Vertical Interconnects Compatible with Semiconductor Technology

Fabrication, Densification, and Replica Molding of 3D Carbon Nanotube Microstructures

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip devices, and their applications. In particular, capabilities for cost-effective fabrication of polymer microstructures were transformed by the advent of soft lithography and other micromolding techniques 1, 2, and this led a revolution in applications of microfabrication to biomedical engineering and biology. Nevertheless, it remains challenging to fabricate microstructures with well-defined nanoscale surface textures, and to fabricate arbitrary 3D shapes at the micro-scale. Robustness of master molds and maintenance of shape integrity is especially important to achieve high fidelity replication of complex structures and preserving their nanoscale surface texture. The combination of hierarchical textures, and heterogeneous shapes, is a profound challenge to existing microfabrication methods that largely rely upon top-down etching using fixed mask templates. On the other hand, the bottom-up synthesis of nanostructures such as nanotubes and nanowires can offer new capabilities to microfabrication, in particular by taking advantage of the collective self-organization of nanostructures, and local control of their growth behavior with respect to microfabricated patterns. 
Our goal is to introduce vertically aligned carbon nanotubes (CNTs), which we refer to as CNT "forests", as a new microfabrication material. We present details of a suite of related methods recently developed by our group: fabrication of CNT forest microstructures by thermal CVD from lithographically patterned catalyst thin films; self-directed elastocapillary densification of CNT microstructures; and replica molding of polymer microstructures using CNT composite master molds. In particular, our work shows that self-directed capillary densification ("capillary forming"), which is performed by condensation of a solvent onto the substrate with CNT microstructures, significantly increases the packing density of CNTs. This process enables directed transformation of vertical CNT microstructures into straight, inclined, and twisted shapes, which have robust mechanical properties exceeding those of typical microfabrication polymers. This in turn enables formation of nanocomposite CNT master molds by capillary-driven infiltration of polymers. The replica structures exhibit the anisotropic nanoscale texture of the aligned CNTs, and can have walls with sub-micron thickness and aspect ratios exceeding 50:1. Integration of CNT microstructures in fabrication offers further opportunity to exploit the electrical and thermal properties of CNTs, and diverse capabilities for chemical and biochemical functionalization 3.

We present methods for fabrication of patterned microstructures of vertically aligned carbon nanotubes (CNTs), and their use as master molds for production of polymer microstructures with organized nanoscale surface texture. The CNT forests are densified by condensation of solvent onto the substrate, which significantly increases their packing density and enables self-directed formation of 3D shapes.

3D 카본 나노튜브 Microstructures의 제조, Densification 및 복제 성형

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip ...

연구

공학

Dry Oxidation and Vacuum Annealing Treatments for Tuning the Wetting Properties of Carbon Nanotube Arrays

In this article, we describe a simple method to reversibly tune the wetting properties of vertically aligned carbon nanotube (CNT) arrays. Here, CNT arrays are defined as densely packed multi-walled carbon nanotubes oriented perpendicular to the growth substrate as a result of a growth process by the standard thermal chemical vapor deposition (CVD) technique.1,2 These CNT arrays are then exposed to vacuum annealing treatment to make them more hydrophobic or to dry oxidation treatment to render them more hydrophilic. The hydrophobic CNT arrays can be turned hydrophilic by exposing them to dry oxidation treatment, while the hydrophilic CNT arrays can be turned hydrophobic by exposing them to vacuum annealing treatment. Using a combination of both treatments, CNT arrays can be repeatedly switched between hydrophilic and hydrophobic.2 Therefore, such combination show a very high potential in many industrial and consumer applications, including drug delivery system and high power density supercapacitors.3-5
The key to vary the wettability of CNT arrays is to control the surface concentration of oxygen adsorbates. Basically oxygen adsorbates can be introduced by exposing the CNT arrays to any oxidation treatment. Here we use dry oxidation treatments, such as oxygen plasma and UV/ozone, to functionalize the surface of CNT with oxygenated functional groups. These oxygenated functional groups allow hydrogen bond between the surface of CNT and water molecules to form, rendering the CNT hydrophilic. To turn them hydrophobic, adsorbed oxygen must be removed from the surface of CNT. Here we employ vacuum annealing treatment to induce oxygen desorption process. CNT arrays with extremely low surface concentration of oxygen adsorbates exhibit a superhydrophobic behavior.

This article describes a simple method to fabricate vertically aligned carbon nanotube arrays by CVD and to subsequently tune their wetting properties by exposing them to vacuum annealing or dry oxidation treatment.

탄소 나노 튜브 배열의 으러 속성을 조정을위한 트리트먼트 소둔 건식 산화, 진공

In this article, we describe a simple method to reversibly  tune the wetting properties of vertically aligned carbon nanotube (CNT) arrays.  Here, CNT ...

Synthesis and Functionalization of Nitrogen-doped Carbon Nanotube Cups with Gold Nanoparticles as Cork Stoppers

Nitrogen-doped carbon nanotubes consist of many cup-shaped graphitic compartments termed as nitrogen-doped carbon nanotube cups (NCNCs). These as-synthesized graphitic nanocups from chemical vapor deposition (CVD) method were stacked in a head-to-tail fashion held only through noncovalent interactions. Individual NCNCs can be isolated out of their stacking structure through a series of chemical and physical separation processes. First, as-synthesized NCNCs were oxidized in a mixture of strong acids to introduce oxygen-containing defects on the graphitic walls. The oxidized NCNCs were then processed using high-intensity probe-tip sonication which effectively separated the stacked NCNCs into individual graphitic nanocups. Owing to their abundant oxygen and nitrogen surface functionalities, the resulted individual NCNCs are highly hydrophilic and can be effectively functionalized with gold nanoparticles (GNPs), which preferentially fit in the opening of the cups as cork stoppers. These graphitic nanocups corked with GNPs may find promising applications as nanoscale containers and drug carriers.

We discussed the synthesis of individual graphitic nanocups using a series of techniques including chemical vapor deposition, acid oxidation and probe-tip sonication. By citrate reduction of HAuCl4, the graphitic nanocups were effectively corked with gold nanoparticles due to the chemically reactive edges of the cups.

코르크 마개로 금 나노 입자와 질소 도핑 된 탄소 나노 튜브 컵의 합성과 기능화

Nitrogen-doped carbon  nanotubes consist of many cup-shaped graphitic compartments termed as  nitrogen-doped carbon nanotube cups (NCNCs).  These ...

Writing and Low-Temperature Characterization of Oxide Nanostructures

Oxide nanoelectronics is a rapidly growing field which seeks to develop novel materials with multifunctional behavior at nanoscale dimensions. Oxide interfaces exhibit a wide range of properties that can be controlled include conduction, piezoelectric behavior, ferromagnetism, superconductivity and nonlinear optical properties. Recently, methods for controlling these properties at extreme nanoscale dimensions have been discovered and developed. Here are described explicit step-by-step procedures for creating LaAlO3/SrTiO3 nanostructures using a reversible conductive atomic force microscopy technique. The processing steps for creating electrical contacts to the LaAlO3/SrTiO3 interface are first described. Conductive nanostructures are created by applying voltages to a conductive atomic force microscope tip and locally switching the LaAlO3/SrTiO3 interface to a conductive state. A versatile nanolithography toolkit has been developed expressly for the purpose of controlling the atomic force microscope (AFM) tip path and voltage. Then, these nanostructures are placed in a cryostat and transport measurements are performed. The procedures described here should be useful to others wishing to conduct research in oxide nanoelectronics.

Oxide nanostructures provide new opportunities for science and technology. The interfacial conductivity between LaAlO3 and SrTiO3 can be controlled with near-atomic precision using a conductive atomic force microscopy technique. The protocol for creating and measuring conductive nanostructures at LaAlO3/SrTiO3 interfaces is demonstrated.

작성 및 산화물 나노 구조의 저온 특성

Oxide nanoelectronics is a rapidly growing field which seeks to develop novel materials with multifunctional behavior at nanoscale dimensions.  Oxide ...

Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures

Layer semiconductors with easily processed two-dimensional (2D) structures exhibit indirect-to-direct bandgap transitions and superior transistor performance, which suggest a new direction for the development of next-generation ultrathin and flexible photonic and electronic devices. Enhanced luminescence quantum efficiency has been widely observed in these atomically thin 2D crystals. However, dimension effects beyond quantum confinement thicknesses or even at the micrometer scale are not expected and have rarely been observed. In this study, molybdenum diselenide (MoSe2) layer crystals with a thickness range of 6-2,700 nm were fabricated as two- or four-terminal devices. Ohmic contact formation was successfully achieved by the focused-ion beam (FIB) deposition method using platinum (Pt) as a contact metal. Layer crystals with various thicknesses were prepared through simple mechanical exfoliation by using dicing tape. Current-voltage curve measurements were performed to determine the conductivity value of the layer nanocrystals. In addition, high-resolution transmission electron microscopy, selected-area electron diffractometry, and energy-dispersive X-ray spectroscopy were used to characterize the interface of the metal&#8211;semiconductor contact of the FIB-fabricated MoSe2 devices. After applying the approaches, the substantial thickness-dependent electrical conductivity in a wide thickness range for the MoSe2-layer semiconductor was observed. The conductivity increased by over two orders of magnitude from 4.6 to 1,500 &#937;&#8722;1 cm&#8722;1, with a decrease in the thickness from 2,700 to 6 nm. In addition, the temperature-dependent conductivity indicated that the thin MoSe2 multilayers exhibited considerably weak semiconducting behavior with activation energies of 3.5-8.5 meV, which are considerably smaller than those (36-38 meV) of the bulk. Probable surface-dominant transport properties and the presence of a high surface electron concentration in MoSe2 are proposed. Similar results can be obtained for other layer semiconductor materials such as MoS2 and WS2.

We describe the approaches for the device fabrication and electrical characterization of molybdenum diselenide (MoSe2) layer semiconductor nanostructures with different thicknesses. In addition, the fabrication of ohmic contacts for MoSe2-layer nanocrystals by the focused-ion beam deposition method using platinum (Pt) as a contact metal is described.

오믹 접촉 제조 집중 이온 빔 기술 및 전기 특성 계층 반도체 나노 구조를 위해 사용

Layer semiconductors with easily processed two-dimensional (2D) structures exhibit indirect-to-direct bandgap transitions and superior transistor ...

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials

Novel electronic materials are often produced for the first time by synthesis processes that yield bulk crystals (in contrast to single crystal thin film synthesis) for the purpose of exploratory materials research. Certain materials pose a challenge wherein the traditional bulk Hall bar device fabrication method is insufficient to produce a measureable device for sample transport measurement, principally because the single crystal size is too small to attach wire leads to the sample in a Hall bar configuration. This can be, for example, because the first batch of a new material synthesized yields very small single crystals or because flakes of samples of one to very few monolayers are desired. In order to enable rapid characterization of materials that may be carried out in parallel with improvements to their growth methodology, a method of device fabrication for very small samples has been devised to permit the characterization of novel materials as soon as a preliminary batch has been produced. A slight variation of this methodology is applicable to producing devices using exfoliated samples of two-dimensional materials such as graphene, hexagonal boron nitride (hBN), and transition metal dichalcogenides (TMDs), as well as multilayer heterostructures of such materials. Here we present detailed protocols for the experimental device fabrication of fragments and flakes of novel materials with micron-sized dimensions onto substrate and subsequent measurement in a commercial superconducting magnet, dry helium close-cycle cryostat magnetotransport system at temperatures down to 0.300 K and magnetic fields up to 12 T.

We describe the methodology of mechanical exfoliation and deposition of flakes of novel materials with micron-sized dimensions onto substrate, fabrication of experimental device structures for transport experimentation, and the magnetotransport measurement in a dry helium close-cycle cryostat at temperatures down to 0.300 K and magnetic fields up to 12 T.

소설 재료의 저온 Magnetotransport 측정을위한 고급 실험 방법

Novel electronic materials are often produced for the first time by synthesis processes that yield bulk crystals (in contrast to single crystal thin film ...

Precision Milling of Carbon Nanotube Forests Using Low Pressure Scanning Electron Microscopy

A nanoscale fabrication technique appropriate for milling carbon nanotube (CNT) forests is described. The technique utilizes an environmental scanning electron microscope (ESEM) operating with a low pressure water vapor ambient. In this technique, a portion of the electron beam interacts with the water vapor in the vicinity of the CNT sample, dissociating the water molecules into hydroxyl radicals and other species by radiolysis. The remainder of the electron beam interacts with the CNT forest sample, making it susceptible to oxidation from the chemical products of radiolysis. This technique may be used to trim a selected region of an individual CNT, or it may be used to remove hundreds of cubic microns of material by adjusting ESEM parameters. The machining resolution is similar to the imaging resolution of the ESEM itself. The technique produces only small quantities of carbon residue along the boundaries of the cutting zone, with minimal effect on the native structural morphology of the CNT forest.

Low pressure scanning electron microscopy in a water vapor ambient is used to machine nanoscale to microscale features in carbon nanotube forests.

저압 주사 전자 현미경을 사용하여 탄소 나노 튜브 숲의 정밀 밀링

A nanoscale fabrication technique appropriate for milling carbon nanotube (CNT) forests is described. The technique utilizes an environmental scanning ...

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia (YSZ) Scaffolds by In Situ Carbon Templating Xerogels

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) scaffolds with tunable specific surface areas up to 80 m2&#183;g-1. An aqueous solution of a zirconium salt, yttrium salt, and glucose is mixed with propylene oxide (PO) to form a gel. The gel is dried under ambient conditions to form a xerogel. The xerogel is pressed into pellets and then sintered in an argon atmosphere. During sintering, a YSZ ceramic phase forms and the organic components decompose, leaving behind amorphous carbon. The carbon formed in situ serves as a hard template, preserving a high surface area YSZ nanomorphology at sintering temperature. The carbon is subsequently removed by oxidation in air at low temperature, resulting in a porous, nanostructured YSZ scaffold. The concentration of the carbon template and the final scaffold surface area can be systematically tuned by varying the glucose concentration in the gel synthesis. The carbon template concentration was quantified using thermogravimetric analysis (TGA), the surface area and pore size distribution was determined by physical adsorption measurements, and the morphology was characterized using scanning electron microscopy (SEM). Phase purity and crystallite size was determined using X-ray diffraction (XRD). This fabrication approach provides a novel, flexible platform for realizing unprecedented scaffold surface areas and nanomorphologies for ceramic-based electrochemical energy conversion applications, e.g. solid oxide fuel cell (SOFC) electrodes.

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels

A protocol for fabricating porous, nanostructured yttria-stabilized-zirconia (YSZ) scaffolds at temperatures between 1,000 &#176;C and 1,400 &#176;C is presented.

에 의한 나노 구조 산화 이트륨 안정화 지르코니아 (YSZ) 비계의 고온 제작<em&gt; 시츄</em&gt; 탄소 템플릿 생성 크 세로 겔

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) ...

Fabrication of 3D Carbon Microelectromechanical Systems (C-MEMS)

A wide range of carbon sources are available in nature, with a variety of micro-/nanostructure configurations. Here, a novel technique to fabricate long and hollow glassy carbon microfibers derived from human hairs is introduced. The long and hollow carbon structures were made by the pyrolysis of human hair at 900 &#176;C in a N2 atmosphere. The morphology and chemical composition of natural and pyrolyzed human hairs were investigated using scanning electron microscopy (SEM) and electron-dispersive X-ray spectroscopy (EDX), respectively, to estimate the physical and chemical changes due to pyrolysis. Raman spectroscopy was used to confirm the glassy nature of the carbon microstructures. Pyrolyzed hair carbon was introduced to modify screen-printed carbon electrodes ; the modified electrodes were then applied to the electrochemical sensing of dopamine and ascorbic acid. Sensing performance of the modified sensors was improved as compared to the unmodified sensors. To obtain the desired carbon structure design, carbon micro-/nanoelectromechanical system (C-MEMS/C-NEMS) technology was developed. The most common C-MEMS/C-NEMS fabrication process consists of two steps: (i) the patterning of a carbon-rich base material, such as a photosensitive polymer, using photolithography; and (ii) carbonization through the pyrolysis of the patterned polymer in an oxygen-free environment. The C-MEMS/NEMS process has been widely used to develop microelectronic devices for various applications, including in micro-batteries, supercapacitors, glucose sensors, gas sensors, fuel cells, and triboelectric nanogenerators. Here, recent developments of a high-aspect ratio solid and hollow carbon microstructures with SU8 photoresists are discussed. The structural shrinkage during pyrolysis was investigated using confocal microscopy and SEM. Raman spectroscopy was used to confirm the crystallinity of the structure, and the atomic percentage of the elements present in the material before and after pyrolysis was measured using EDX.

Fabrication of 3D Carbon Microelectromechanical Systems C-MEMS

Long and hollow glassy carbon microfibers were fabricated based on the pyrolysis of a natural product, human hair. The two fabrication steps of carbon microelectromechanical and carbon nanoelectromechanical systems, or C-MEMS and C-NEMS, are: (i) photolithography of a carbon-rich polymer precursor and (ii) pyrolysis of the patterned polymer precursor.

3D 탄소 미세 전자 기계 시스템 (C-MEMS) 제작

A wide range of carbon sources are available in nature, with a variety of micro-/nanostructure configurations. Here, a novel technique to fabricate long ...

Flow-assisted Dielectrophoresis: A Low Cost Method for the Fabrication of High Performance Solution-processable Nanowire Devices

Flow-assisted dielectrophoresis (DEP) is an efficient self-assembly method for the controllable and reproducible positioning, alignment, and selection of nanowires. DEP is used for nanowire analysis, characterization, and for solution-based fabrication of semiconducting devices. The method works by applying an alternating electric field between metallic electrodes. The nanowire formulation is then dropped onto the electrodes which are on an inclined surface to create a flow of the formulation using gravity. The nanowires then align along the gradient of the electric field and in the direction of the liquid flow. The frequency of the field can be adjusted to select nanowires with superior conductivity and lower trap density. 
In this work, flow-assisted DEP is used to create nanowire field effect transistors. Flow-assisted DEP has several advantages: it allows selection of nanowire electrical properties; control of nanowire length; placement of nanowires in specific areas; control of orientation of nanowires; and control of nanowire density in the device. 
The technique can be expanded to many other applications such as gas sensors and microwave switches. The technique is efficient, quick, reproducible, and it uses a minimal amount of dilute solution making it ideal for the testing of novel nanomaterials. Wafer scale assembly of nanowire devices can also be achieved using this technique, allowing large numbers of samples for testing and large-area electronic applications.

In this paper, flow assisted dielectrophoresis is demonstrated for the self-assembly of nanowire devices. The fabrication of a silicon nanowire field effect transistor is shown as an example.

흐름 기반 Dielectrophoresis: 고성능 솔루션 처리 나노와이어 소자의 제조에 대 한 낮은 비용 방법

Flow-assisted dielectrophoresis (DEP) is an efficient self-assembly method for the controllable and reproducible positioning, alignment, and selection of ...