Thanks to Michael Knutson, Paul Hamric, Greg Scott, and Chris Landes for helpful discussions and assistance related to the custom inert atmosphere sample holder and assistance in the University of Utah student machine shop. P.C. acknowledges the NSF GRFP under Grant No. 0750758. P.C. acknowledges the University of Utah Nanotechnology Training Fellowship. R.M. acknowledges a NSF CAREER Award No. 1054899 and funding from the USTAR Initiative.

참고 : 클린 룸 클래스 100 조건 또는 더 나은 아래의 모든 다음 단계를 수행하십시오. 1. 샘플 준비 <ol><li> (: 유해 화학 물질주의) 2 분 동안 버퍼 산화물 에칭 (BOE) 솔루션 (6 부품 40 % NH 4 F 1 부 49 %의 HF)와 2 &quot;직경의 실리콘 웨이퍼를 청소합니다. 표면에있는 유기물이나 오염 물질을 제거하려면이 에칭 시간을 선택합니다. 약 5 분 동안 탈 이온수 (DI) 물에 씻어. 건조 N 2와 건조 웨이퍼. 참고 : HF를 사용하는 경우 혼자 작업하지 마십시오. 항상 흩날 린 경우 얼굴 방패와 개인 보호 장비 (PPE)와 눈 보호를 착용합니다. 에칭이 수행 된 실험실에서 사용 및 HF 폐기물의 처리를위한 포스트 지침. 참고 : 전기 잠금만을위한 1.2-1.7 단계를 반복합니다. 용해를 통해 잠금을 수행하는 경우 2 단계로 진행합니다. </li><li> , 작동 전극을 버리는 깨끗한 2 &quot;직경 silic에 백금 (PT)의 100 nm의 스퍼터웨이퍼에. </li><li> 백금 박막을 에칭하기 전에, 이전의 건조 식각에서 불순물 또는 남은 포토 레지스트의 RIE 챔버를 청소합니다. </li><li> 토르 달성 1 × 10-5의 기본 압력까지 챔버를 펌프 다운. RF 전력은 200 W로 설정하고, 산소 및 아르곤의 유속은 각각 50 SCCM과 10 SCCM으로 설정되어 있는지 확인. 아르곤 / O 2 플라즈마 점화 적어도 1 시간 동안 실행합니다. </li><li> 아르곤 / O 2 플라즈마를 끄고 챔버는 약 10 분 동안 배출 할 수 있습니다. </li><li> 백금 박막 표면을 에칭하기 위하여, RIE 챔버로 샘플을 로딩하고 1 × 10-5 토르의 기본 압력까지 펌프 챔버. 이 시간에 0 SCCM 아르곤 유속을 설정. O 2 플라즈마를 점화하고이 과정이 30 분 동안 실행하자. </li><li> O 2 플라즈마를 끄고 챔버가 10 분 동안 배출 할 수 있습니다. </li></ol> 사용자 정의 L을 사용하여 광 변색 분자의 2 열 증발오우 온도 증발기 (LTE) <ol><li> BTE 30 밀리그램 무조건 2 배를 채우고 사용자 정의 LTE 소스 (그림 6)에로드. </li><li> 샘플에 넣 실리콘 웨이퍼를 탑재합니다. </li><li> 일실 포트와 펌프실 1 × 10-6 토르의 기본 압력으로 내려. </li><li> 30 nm의 막 두께, 100 ° C의 온도 설정치 BTE를 증발시켰다. </li><li> 즉시 증발 후, 홍수, 닫힌 형태로 1C을 BTE 재료를 변환하는 UV의 5 분에 샘플을 조명. </li><li> 샘플 크기를 정의하기 위해, 실리콘 표면의 가장자리에서 선 스크래치 다이아몬드 스크라이브를 사용하여 웨이퍼의 작은 조각을 절단. 스크래치 라인의 양측을 잡아 웨이퍼는 결정면을 따라 중단 될 때까지 아래쪽으로 구부러 웨이퍼. </li><li> BTE에게 얇은 막 두께를 확인하는 프로파일로 측정을 수행. 이렇게하려면 미세 에지 핀셋을 사용하여 샘​​플에 상처. 이리저리 스텝 높이를 측정m 좌우 커서 위치 사이의 높이 차이이 스크래치. 주 : 막 두께의 부정확성 노광량에 차이가 발생할 것이다. </li><li> N이 가득 글러브 박스에 보관 나머지 샘플. </li></ol> 3. 노출 주 : 시료의 열화를 방지하기 위해 불활성 분위기 조건에서 모든 노출을 수행한다. <ol><li> 단계 2.6에서 설명한 것과 동일한 절차에 따라 샘플을 쪼개짐. </li><li> 불활성 분위기 샘플 홀더로드 샘플. </li><li> 무대에 불활성 샘플 홀더를 탑재합니다. N 2 퍼지 샘플. </li><li> 예컨대도 8에 도시 한 바와 같이, 간섭계를 사용하여 소망의 노출 시간에 샘플을 노출. </li></ol> 세 개의 전극 셀을 사용 4. 전기 화학적 산화 주 : 시료의 열화를 방지하기 위해 불활성 분위기 조건에서 전기 화학을 수행한다. <ol><li> 핫 플레이트 위에 깨끗한 유리 병을 클램프. 유리 병에 깨끗한 교반 막대를 놓습니다. 교반기를 켭니다. </li><li> 메탄올 새로운 구리 클립을 청소합니다. 메탄올 백금 상대 전극을 청소합니다. </li><li> 깨끗한 구리 클립을 이용하여 테플론 병 뚜껑의 구멍 중 하나를 통해 샘플 클립. 만 노출 된 백금에 클립해야합니다. </li><li> 유리 병 위에 테프론 유리 병 뚜껑을 놓습니다. 백금 카운터 전극과 샘플을 들고 구리 클립 위에 흑연에 적색 리드를 클립. </li><li> 깨끗한 주사기를 사용하여 테프론 유리 병 캡에서 두 번째 구멍을 통해 여과 탈 (DI) 물을 유리 병을 채 웁니다. 샘플에 노출 된 백금의 몰입하지 않고 높은 입력합니다. </li><li> 3-5 분 동안 물을 통해 거품 질소. 질소를 끕니다. </li><li> 테프론 유리 병 캡에서 두 번째 구멍에 기준 전극을 배치합니다. 기준 전극에 흰색 리드를 클립. 베어 백금 O를 확인 아무것도하지 않습니다 확인n은 샘플을 담근다. </li><li> voltammograph를 사용하여, 0.5 V / 초의 산화 전압을 설정한다. </li><li> 원하는 산화 시간이 경과 한 후, voltammograph 오프에 전원을 켭니다. </li><li> 백금 상대 전극, 구리 클립 및 기준 전극에서, 빨강, 검정, 흰색 클립을 제거합니다. </li><li> 5 분 동안 UV하기 위해 샘플을 노출. </li></ol> 5. 샘플 개발 - 전기 잠금 주 : 시료의 열화를 방지하기 위해 비활성 분위기 조건으로 발전을 수행한다. <ol><li> 여과 5 (중량 %) 이소프로판올 샘플을 개발 시간의 원하는 양 95 (중량 %) 에틸렌 글리콜. 참고 : 80 nm의 샘플은 60-180 초 동안 개발하는 동안 일반적으로 50 나노 샘플이 30 ~ 60 초 동안 개발된다. </li><li> 건조 N 2와 건조 샘플. </li><li> 즉시 UV의 5 분에 샘플을 노출. </li></ol> 6. 샘플 개발 - 해산 잠금 </em&gt; 주 : 시료의 열화를 방지하기 위해 비활성 분위기 조건으로 발전을 수행한다. <ol><li> 깨끗한 유리 비이커에 에틸렌 글리콜 100 ㎖를 사용하여, 원하는 현상 시간 샘플에 대한 노출을 개발한다. </li><li> 건조 N 2와 건조 샘플. 즉시 UV의 5 분에 샘플을 노출. </li></ol> 7. 다중 노출 <ol><li> 다중 노출의 반복을 수행하면 광학에 샘플 상대의 번역 3-6 단계를 반복합니다. </li></ol>

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The authors have nothing to disclose.

The fabrication, experimental setup and related operational procedures of Patterning via Optical Saturable Transitions (POST) have been described. By exploiting the linear switching properties of thermally stable photochromic molecules, POST offers new perspectives on circumventing the far-field diffraction limit.1-2,4
Previously long-term storage requirement of the samples was solved by storing the samples under N2, directly after the initial evaporation.2 How...

광학 리소그래피는 나노 구조 및 장치의 제조에 대단히 중요하다. 새로운 리소그래피 기술의 향상 발전은 새로운 장치의 새로운 세대를 가능하게하는 기능이있다. 8 ~ 11이 글에서 검토가 새로운 환성 분자를 사용하여 깊은 파장 이하의 해상도를 달성 광 리소그래피 기술의 클래스 표시됩니다. 이 방법은 광학 - 가포 전환 (POST)를 통해 패턴 화라고합니다. 1-3 POST 고유 즉, (1,2- 비스 (5,5&#39;- 디메틸 -2,2&#39;- bithiophen 일))의 광 변색 성 분자 천이 포화의 사상을 겸비한 신규 한 나노 기술 perfluorocyclopent -1- 엔이다. 놓고,이 화합물을 그 larg의 강력한 도구하게 간섭 리소그래피와 같은 유도 방출 핍층 (STED) 현미경 (12)에 사용되는 것과 같은 BTE,도 1이라2 및 3 차원의 잠재적 인 확장과 다양한 표면 위에 깊은 서브 파장 기능의 전자 영역 병렬 나노 패터닝. 광 변색 층은 원래 하나의 균질 한 상태입니다. 이 층은 λ (1)의 균일 한 조명에 노출되는 경우, 제 2 이성체 상태 (도 1c),도 2로 변환한다. 그 후 샘플은 제 이성체 상태로 샘플 (변환 λ (2)에 포커싱 된 노드에 노출 1O) 사방 노드의 근처 부근에서 제외. 노광량을 제어함으로써, 전환되지 않은 영역의 크기는 임의로 작게 만들어 질 수있다. 이성체 중 하나의 후속 정착 단계는 선택적으로 패턴을 비가 역적으로 잠글 (블랙) 3 차 상태 (잠금) 변환 될 수있다. 이어서, 층을 다시 원래의 상태로 락 영역을 제외한 모든 변환 한 λ, 균일 노출된다.단계들의 시퀀스는 그 간격 원방 회절 한계보다 작은 두 잠긴 영역 결과적으로 광학 샘플의 상대 변위로 반복 될 수있다. 따라서, 임의의 형상은 &quot;도트 매트릭스&quot;방식으로 패턴 화 될 수있다. 1-3

<table border="0" cellpadding="0" cellspacing="0" width="778">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:205px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:239px;">Comments/Description</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Isopropanol</td>
			<td style="width:205px;">Fisher Scientific</td>
			<td style="width:119px;">P/7500/15</td>
			<td style="width:239px;">CAUTION: flammable, use good 
			ventilation and avoid all ignition 
			sources.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Buffered Oxide Etch</td>
			<td style="width:205px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Methanol</td>
			<td style="width:205px;">Ricca Chemical</td>
			<td style="width:119px;">48-293-2&#160;</td>
			<td style="width:239px;">CAUTION: flammable, use good 
			ventilation and avoid all ignition 
			sources.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Ethylene Glycol</td>
			<td style="width:205px;">Sigma-Aldrich</td>
			<td style="width:119px;">324558</td>
			<td>CAUTION: Harmful if swallowed</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Silicon wafer</td>
			<td style="width:205px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Diamond Scribe</td>
			<td style="width:205px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Glass Beakers</td>
			<td style="width:205px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Tweezers</td>
			<td style="width:205px;">Ted Pella</td>
			<td style="width:119px;">5226</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Reactive Ion Etching System</td>
			<td style="width:205px;">Oxford</td>
			<td style="width:119px;">Plasma Lab 80 Plus</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Inert Atmosphere Sample Holder</td>
			<td style="width:205px;">Proprietary In-house Designed</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Polarizing beamsplitter cube</td>
			<td style="width:205px;">Thorlabs</td>
			<td style="width:119px;">PBS052</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">HeNe Laser</td>
			<td style="width:205px;">Melles Griot</td>
			<td style="width:119px;">25-LHP-171</td>
			<td>CAUTION: Wear safety glasses</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Half-wave plates</td>
			<td style="width:205px;">Thorlabs</td>
			<td style="width:119px;">WPH05M-633</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Thermal Evaporator</td>
			<td style="width:205px;">Proprietary In-house Designed</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">TMV Super</td>
			<td style="width:205px;">TM Vacuum Products</td>
			<td style="width:119px;">TMV Super</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Voltammograph</td>
			<td style="width:205px;">Bioanalytical Systems</td>
			<td style="width:119px;">CV-37</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Shortwave UV lamp 365nm</td>
			<td style="width:205px;">UVP Analytik Jena Company</td>
			<td style="width:119px;">UVGL-25</td>
			<td>CAUTION: Wear UV safety glasses</td>
		</tr>
	</tbody>
</table>

patterning via optical saturable transitions - fabrication and characterization

This protocol describes the fabrication and characterization of nanostructures using a novel nanolithographic technique called Patterning via Optical Saturable Transitions (POST). In this technique the chemical properties of organic photochromic molecules that undergo single-photon reactions are exploited, enabling rapid top-down nanopatterning over large areas at low light intensities, thereby, allowing for the circumvention of the far-field diffraction barrier.4 Simple, cost-effective, high throughput and resolution alternatives to nanopatterning are being explored, such as, two-photon polymerization5,6, beam pen lithography (BPL)7, scanning electron beam lithography (SEBL), and focused ion beam (FIB) patterning. However, multi-photon approaches require high light intensities, which limit their potential for high throughput and offer low image contrast. Although, electron and ion beam lithographic processes offer increased resolution, the serial nature of the process is limited to slow writing speeds, which also prevents patterning of features over large areas. Beam-pen lithography is an approach towards parallel near-field optical lithography. However, the gap between the source of the beam and the surface of the photoresist needs to be controlled extremely precisely for good pattern uniformity and this is very challenging to accomplish for large arrays of beams. Patterning via Optical Saturable Transitions (POST) is an alternative optical nanopatterning technique for patterning sub-wavelength features1-3. Since this technique uses single photons instead of electrons, it is extremely fast and does not require high light intensities1-3, opening the door to massive parallelization.

제작 된 샘플 : 순환 전압 전류 측정에서 0.85 V의 산화 전압을도 3에서의 원자 힘 현미경 사진에 의해 도시 된 바와 같이, 상이한 산화 시간은 특성화 하였다. 50 nm 두께의 필름은 0.95 mW의 / ㎠의 전력 밀도에서 60 초 동안 400 nm 인 λ = 647 nm에서 정재파 노출시켰다. 산화 시간을 25 분에서 10 분으로 증가함에 1O 이루어지는 영역의 일부...

Watch this Scientific Journal Video about Patterning via Optical Saturable Transitions - Fabrication and Characterization at JoVE.com

Patterning via Optical Saturable Transitions - Fabrication and Characterization

We report that the diffraction limit of conventional optical lithography can be overcome by exploiting the transitions of organic photochromic derivatives induced by their photoisomerization at low light intensities.1-3 This paper outlines our fabrication technique and two locking mechanisms, namely: dissolution of one photoisomer and electrochemical oxidation.

광학 가포 전환을 통해 패터닝 - 제조 및 특성

This protocol describes the fabrication and characterization of nanostructures using a novel nanolithographic technique called Patterning via Optical ...

patterning-via-optical-saturable-transitions-fabrication

Research

JoVE Journal

Engineering

6.7K 조회수.  The University of Utah. We report that the diffraction limit of conventional optical lithography can be overcome by exploiting the transitions of organic photochromic derivatives induced by their photoisomerization at low light intensities.1-3 This paper outlines our fabrication technique and two locking mechanisms, namely: dissolution of one photoisomer and electrochemical oxidation.

비디오: Patterning via Optical Saturable Transitions - Fabrication and Characterization

Simulation, Fabrication and Characterization of THz Metamaterial Absorbers

Metamaterials (MM), artificial materials engineered to have properties that may not be found in nature, have been widely explored since the first theoretical1 and experimental demonstration2 of their unique properties. MMs can provide a highly controllable electromagnetic response, and to date have been demonstrated in every technologically relevant spectral range including the optical3, near IR4, mid IR5 , THz6 , mm-wave7 , microwave8 and radio9 bands. Applications include perfect lenses10, sensors11, telecommunications12, invisibility cloaks13 and filters14,15. We have recently developed single band16, dual band17 and broadband18 THz metamaterial absorber devices capable of greater than 80% absorption at the resonance peak. The concept of a MM absorber is especially important at THz frequencies where it is difficult to find strong frequency selective THz absorbers19. In our MM absorber the THz radiation is absorbed in a thickness of ~ &lambda;/20, overcoming the thickness limitation of traditional quarter wavelength absorbers. MM absorbers naturally lend themselves to THz detection applications, such as thermal sensors, and if integrated with suitable THz sources (e.g. QCLs), could lead to compact, highly sensitive, low cost, real time THz imaging systems.

This protocol outlines the simulation, fabrication and characterization of THz metamaterial absorbers. Such absorbers, when coupled with an appropriate sensor, have applications in THz imaging and spectroscopy.

THz Metamaterial Absorbers 시뮬레이션, 제조 및 특성

Metamaterials (MM),  artificial materials engineered to have properties that may not be found in  nature, have been widely explored since the first ...

연구

공학

Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities

Slow light has been one of the hot topics in the photonics community in the past decade, generating great interest both from a fundamental point of view and for its considerable potential for practical applications. Slow light photonic crystal waveguides, in particular, have played a major part and have been successfully employed for delaying optical signals1-4 and the enhancement of both linear5-7 and nonlinear devices.8-11
Photonic crystal cavities achieve similar effects to that of slow light waveguides, but over a reduced band-width. These cavities offer high Q-factor/volume ratio, for the realization of optically12 and electrically13 pumped ultra-low threshold lasers and the enhancement of nonlinear effects.14-16 Furthermore, passive filters17 and modulators18-19 have been demonstrated, exhibiting ultra-narrow line-width, high free-spectral range and record values of low energy consumption.
To attain these exciting results, a robust repeatable fabrication protocol must be developed. In this paper we take an in-depth look at our fabrication protocol which employs electron-beam lithography for the definition of photonic crystal patterns and uses wet and dry etching techniques. Our optimised fabrication recipe results in photonic crystals that do not suffer from vertical asymmetry and exhibit very good edge-wall roughness. We discuss the results of varying the etching parameters and the detrimental effects that they can have on a device, leading to a diagnostic route that can be taken to identify and eliminate similar issues.
The key to evaluating slow light waveguides is the passive characterization of transmission and group index spectra. Various methods have been reported, most notably resolving the Fabry-Perot fringes of the transmission spectrum20-21 and interferometric techniques.22-25 Here, we describe a direct, broadband measurement technique combining spectral interferometry with Fourier transform analysis.26 Our method stands out for its simplicity and power, as we can characterise a bare photonic crystal with access waveguides, without need for on-chip interference components, and the setup only consists of a Mach-Zehnder interferometer, with no need for moving parts and delay scans.
When characterising photonic crystal cavities, techniques involving internal sources21 or external waveguides directly coupled to the cavity27 impact on the performance of the cavity itself, thereby distorting the measurement. Here, we describe a novel and non-intrusive technique that makes use of a cross-polarised probe beam and is known as resonant scattering (RS), where the probe is coupled out-of plane into the cavity through an objective. The technique was first demonstrated by McCutcheon et al.28 and further developed by Galli et al.29

Use of photonic crystal slow light waveguides and cavities has been widely adopted by the photonics community in many differing applications. Therefore fabrication and characterization of these devices are of great interest. This paper outlines our fabrication technique and two optical characterization methods, namely: interferometric (waveguides) and resonant scattering (cavities).

광자 크리스탈 느린 경 Waveguides 그리고 안의 공간의 제조 및 특성

Slow light has been one of the hot topics in the photonics community in the past decade, generating great interest both from a fundamental point of view ...

Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters

In this video article we present a detailed demonstration of a highly efficient method for generating terahertz waves. Our technique is based on photoconduction, which has been one of the most commonly used techniques for terahertz generation 1-8. Terahertz generation in a photoconductive emitter is achieved by pumping an ultrafast photoconductor with a pulsed or heterodyned laser illumination. The induced photocurrent, which follows the envelope of the pump laser, is routed to a terahertz radiating antenna connected to the photoconductor contact electrodes to generate terahertz radiation. Although the quantum efficiency of a photoconductive emitter can theoretically reach 100%, the relatively long transport path lengths of photo-generated carriers to the contact electrodes of conventional photoconductors have severely limited their quantum efficiency. Additionally, the carrier screening effect and thermal breakdown strictly limit the maximum output power of conventional photoconductive terahertz sources. To address the quantum efficiency limitations of conventional photoconductive terahertz emitters, we have developed a new photoconductive emitter concept which incorporates a plasmonic contact electrode configuration to offer high quantum-efficiency and ultrafast operation simultaneously. By using nano-scale plasmonic contact electrodes, we significantly reduce the average photo-generated carrier transport path to photoconductor contact electrodes compared to conventional photoconductors 9. Our method also allows increasing photoconductor active area without a considerable increase in the capacitive loading to the antenna, boosting the maximum terahertz radiation power by preventing the carrier screening effect and thermal breakdown at high optical pump powers. By incorporating plasmonic contact electrodes, we demonstrate enhancing the optical-to-terahertz power conversion efficiency of a conventional photoconductive terahertz emitter by a factor of 50 10.

We describe methods for the design, fabrication, and experimental characterization of plasmonic photoconductive emitters, which offer two orders of magnitude higher terahertz power levels compared to conventional photoconductive emitters.

Plasmonic의 광전 테라 헤르츠 터의 설계, 제작 및 실험 특성

In this video article we present a detailed demonstration of a highly efficient method for generating terahertz waves. Our technique is based on ...

Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed polymer optical fiber is composed of 80,000 strands of poly (methyl methacrylate) (PMMA) and polystyrene (PS) that are randomly mixed and drawn into a square cross section optical fiber with a side width of 250 &mu;m. Initially, each strand is 200 &mu;m in diameter and 8-inches long. During the mixing process of the original fiber strands, the fibers cross over each other; however, a large draw ratio guarantees that the refractive index profile is invariant along the length of the fiber for several tens of centimeters. The large refractive index difference of 0.1 between the disordered sites results in a small localized beam radius that is comparable to the beam radius of conventional optical fibers. The input light is launched from a standard single mode optical fiber using the butt-coupling method and the near-field output beam from the disordered fiber is imaged using a 40X objective and a CCD camera. The output beam diameter agrees well with the expected results from the numerical simulations. The disordered optical fiber presented in this work is the first device-level implementation of 2D Anderson localization, and can potentially be used for image transport and short-haul optical communication systems.

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. This microstructured fiber can transport a small localized beam with a radius that is comparable to the beam radius of conventional optical fibers.

빛의 통과 앤더슨 현지화 무질서 폴리머 광섬유의 제조 및 특성

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed ...

Fabrication of Uniform Nanoscale Cavities via Silicon Direct Wafer Bonding

Measurements of the heat capacity and superfluid fraction of confined 4He have been performed near the lambda transition using lithographically patterned and bonded silicon wafers. Unlike confinements in porous materials often used for these types of experiments3, bonded wafers provide predesigned uniform spaces for confinement. The geometry of each cell is well known, which removes a large source of ambiguity in the interpretation of data.
Exceptionally flat, 5 cm diameter, 375 &#181;m thick Si wafers with about 1 &#181;m variation over the entire wafer can be obtained commercially (from Semiconductor Processing Company, for example). Thermal oxide is grown on the wafers to define the confinement dimension in the z-direction. A pattern is then etched in the oxide using lithographic techniques so as to create a desired enclosure upon bonding. A hole is drilled in one of the wafers (the top) to allow for the introduction of the liquid to be measured. The wafers are cleaned2 in RCA solutions and then put in a microclean chamber where they are rinsed with deionized water4. The wafers are bonded at RT and then annealed at ~1,100 &#176;C. This forms a strong and permanent bond. This process can be used to make uniform enclosures for measuring thermal and hydrodynamic properties of confined liquids from the nanometer to the micrometer scale.

A method for permanently bonding two silicon wafers so as to realize a uniform enclosure is described. This includes wafer preparation, cleaning, RT bonding, and annealing processes. The resulting bonded wafers (cells) have uniformity of enclosure ~1%1,2. The resulting geometry allows for measurements of confined liquids and gasses.

실리콘 다이렉트 웨이퍼 본딩을 통한 균일한 나노스케일 캐비티 제조

Measurements of the heat capacity and superfluid fraction of confined 4He have been performed near the lambda transition using lithographically patterned ...

Fabrication and Operation of a Nano-Optical Conveyor Belt

The technique of using focused laser beams to trap and exert forces on small particles has enabled many pivotal discoveries in the nanoscale biological and physical sciences over the past few decades. The progress made in this field invites further study of even smaller systems and at a larger scale, with tools that could be distributed more easily and made more widely available. Unfortunately, the fundamental laws of diffraction limit the minimum size of the focal spot of a laser beam, which makes particles smaller than a half-wavelength in diameter hard to trap and generally prevents an operator from discriminating between particles which are closer together than one half-wavelength. This precludes the optical manipulation of many closely-spaced nanoparticles and&#160;limits the&#160;resolution of optical-mechanical systems. Furthermore, manipulation using focused beams requires beam-forming or steering optics, which can be very bulky and expensive. To address these limitations in the system scalability of conventional optical trapping our lab has devised an alternative technique which utilizes near-field optics to move particles across a chip. Instead of focusing laser beams in the far-field, the optical near field of plasmonic resonators produces the necessary local optical intensity enhancement to overcome the restrictions of diffraction and manipulate particles at higher resolution. Closely-spaced resonators produce strong optical traps which can be addressed to mediate the hand-off of particles from one to the next in a conveyor-belt-like fashion. Here, we describe how to design and produce a conveyor belt using a gold surface patterned with plasmonic C-shaped resonators and how to operate it with polarized laser light to achieve super-resolution nanoparticle manipulation and transport. The nano-optical conveyor belt chip can be produced using lithography techniques and easily packaged and distributed.

The scalability and resolution of conventional optical manipulation techniques are limited by diffraction. We circumvent the diffraction limit and describe a method of optically transporting nanoparticles across a chip using a gold surface patterned with a path of closely spaced C-shaped plasmonic resonators.

나노 광학 컨베이어 벨트의 제작 및 운영

The technique of using focused laser beams to trap and exert forces on small particles has enabled many pivotal discoveries in the nanoscale biological ...

Compact Lens-less Digital Holographic Microscope for MEMS Inspection and Characterization

A micro-electro-mechanical-system (MEMS) is a widely used component in many industries, including energy, biotechnology, medical, communications, and automotive. However, effective inspection and characterization metrology systems are needed to ensure the functional reliability of MEMS. This study presents a system based on digital holography as a tool for MEMS metrology. Digital holography has gained increasing attention in the past 20 years. With the fast development and decreasing cost of sensor arrays, resolution of such systems has increased broadening potential applications. Thus, it has attracted attention from both research and industry sides as a potential reliable tool for industrial metrology. Indeed, by recording the interference pattern between an object beam (which contains sample height information) and a reference beam on a CCD camera, one can retrieve the quantitative phase information of an object. However, most of digital holographic systems are bulky and thus not easy to implement on industry production lines. The novelty of the system presented is that it is lens-less and thus very compact. In this study, it is shown that the Compact Digital Holographic Microscope (CDHM) can be used to evaluate several characteristics typically consider as criteria in MEMS inspections. The surface profiles of MEMS in both static and dynamic conditions are presented. Comparison with AFM is investigated to validate the accuracy of the CDHM.

We present a compact reflection digital holographic system (CDHM) for inspection and characterization of MEMS devices. A lens-less design using a diverging input wave providing natural geometrical magnification is demonstrated. Both static and dynamic studies are presented.

MEMS 검사 및 특성화를위한 소형 렌즈가없는 디지털 홀로그램 현미경

A micro-electro-mechanical-system (MEMS) is a widely used component in many industries, including energy, biotechnology, medical, communications, and ...

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Here, we present a protocol to fabricate organic thin film solar cells using a mini-slot die coater and related in-line structure characterizations using synchrotron scattering techniques.

벌크 이종 접합 태양 전지의 인쇄 제작 및<em&gt; 현장에서</em&gt; 형태학 특성

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices ...

Fabrication and Characterization of Superconducting Resonators

Superconducting microwave resonators are of interest for a wide range of applications, including for their use as microwave kinetic inductance detectors (MKIDs) for the detection of faint astrophysical signatures, as well as for quantum computing applications and materials characterization. In this paper, procedures are presented for the fabrication and characterization of thin-film superconducting microwave resonators. The fabrication methodology allows for the realization of superconducting transmission-line resonators with features on both sides of an atomically smooth single-crystal silicon dielectric. This work describes the procedure for the installation of resonator devices into a cryogenic microwave testbed and for cool-down below the superconducting transition temperature. The set-up of the cryogenic microwave testbed allows one to do careful measurements of the complex microwave transmission of these resonator devices, enabling the extraction of the properties of the superconducting lines and dielectric substrate (e.g., internal quality factors, loss and kinetic inductance fractions), which are important for device design and performance.

Superconducting microwave resonators are of interest for detection of light, quantum computing applications and materials characterization. This work presents a detailed procedure for fabrication and characterization of superconducting microwave resonator scattering parameters.

초전도 공진기의 제조 및 특성

Superconducting microwave resonators are of interest for a wide range of applications, including for their use as microwave kinetic inductance detectors ...

Fabrication of Polymer Microspheres for Optical Resonator and Laser Applications

This paper describes three methods of preparing fluorescent microspheres comprising &#960;-conjugated or non-conjugated polymers: vapor diffusion, interface precipitation, and mini-emulsion. In all methods, well-defined, micrometer-sized spheres are obtained from a self-assembling process in solution. The vapor diffusion method can result in spheres with the highest sphericity and surface smoothness, yet the types of the polymers able to form these spheres are limited. On the other hand, in the mini-emulsion method, microspheres can be made from various types of polymers, even from highly crystalline polymers with coplanar, &#960;-conjugated backbones. The photoluminescent (PL) properties from single isolated microspheres are unusual: the PL is confined inside the spheres, propagates at the circumference of the spheres via the total internal reflection at the polymer/air interface, and self-interferes to show sharp and periodic resonant PL lines. These resonating modes are so-called "whispering gallery modes" (WGMs). This work demonstrates how to measure WGM PL from single isolated spheres using the micro-photoluminescence (&#181;-PL) technique. In this technique, a focused laser beam irradiates a single microsphere, and the luminescence is detected by a spectrometer. A micromanipulation technique is then used to connect the microspheres one by one and to demonstrate the intersphere PL propagation and color conversion from coupled microspheres upon excitation at the perimeter of one sphere and detection of PL from the other microsphere. These techniques, &#181;-PL and micromanipulation, are useful for experiments on micro-optic application using polymer materials.

Protocols for the synthesis of microspheres from polymers, the manipulation of microspheres, and micro-photoluminescence measurements are presented.