• 한국진공학회지
• /
• 제7권2호
• /
• pp.150-154
• /
• 1998

실리콘산화막에 실리콘이온주입을 $5\times1016/\textrm{cm}^2, 1\times10^{17}/\textrm{cm}^2, 3\times10^{17}/\textrm{cm}^2$으로 하여 열처리온도와 열처리시간을 변화시키면서 광루미니센스, XRD, TEM을 관찰하였다. 이온주 입량이 적고 열처리온도가 낮을경우에 가시광 광루미니센스를 관찰할 수 있었다. 광루미니 센스의 peak는 7420$\AA$과 8360$\AA$위치에 있었으며, 열처리시간이 길어짐에 따라 intensity는 각각 증가하였다. 이온주입량이 많고 열처리온도가 높을경우에는 광루미니센스가 관찰되지 않았다. 이온주입량이 적고 열처리 온도가 높을경우에는 열처리시간이 짧으면 가시광 광루 미니센스가 있으나 열처리시간이 1시간 이상으로 길어지면 광루미니센스가 사라졌다. XRD 와 TEM결과로부터 실리콘 cluster는 nonradiative defect와 관련있으며, 실리콘이온주입된 실리콘산화막에서 관찰되는 광루미니센스의 origin은 nanocrystal이 아니라 defect임을 알 수 있었다. 이온주입되는 실리콘이온의 량, 열처리온도와 시간의 변화는 광루미니센스를 변 화시키는데 이 현상들을 Si-O-O결합인 O위주의 결함과 Si-Si-O결합인 Si위주의 결함과 연 관지어 설명할 수 있었다.

• 한국전기전자재료학회논문지
• /
• 제14권1호
• /
• pp.1-5
• /
• 2001

STI(shallow trench isolation)-CMP(chemical mechanical polishing) process have been substituted for LOCOS(local oxidation of silicon) process to obtain global planarization in the below sub-0.5㎛ technology. However TI-CMP process, especially TI-CMP with RIE(reactive ion etching) etch back process, has some kinds of defect like nitride residue, torn oxide defect, etc. In this paper, we studied how to reduced torn oxide defects after STI-CMP with RIE etch back processed. Although torn oxide defects which can occur on trench area is not deep and not severe, torn oxide defects on moat area is not deep and not severe, torn oxide defects on moat area is sometimes very deep and makes the yield loss. Thus, we did test on pattern wafers which go through trench process, APECVD process, and RIE etch back process by using an IPEC 472 polisher, IC1000/SUVA4 PAD and KOH base slurry to reduce the number of torn defects and to study what is the origin of torn oxide defects.

• Applied Microscopy
• /
• 제45권3호
• /
• pp.107-114
• /
• 2015

Two-dimensional (2D) materials containing hole defects are a promising substitute for conventional nanopore membranes like silicon nitride. Hole defects on 2D materials, as atomically thin nanopores, have been used in nanopore devices, such as DNA sensor, gas sensor and purifier at lab-scale. For practical applications of 2D materials to nanopore devices, researches on characteristics of hole defects on graphene, hexagonal boron nitride and molybdenum disulfide have been conducted precisely using transmission electron microscope. Here, we summarized formation, features, structural preference and stability of hole defects on 2D materials with atomic-resolution transmission electron microscope images and theoretical calculations, emphasizing the future challenges in controlling the edge structures and stabilization of hole defects. Exploring the properties at the local structure of hole defects through in situ experiments is also the important issue for the fabrication of realistic 2D nanopore devices.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2005년도 춘계학술대회
• /
• pp.98-101
• /
• 2005

변환 효율이 $16\%$에 근접하는 다결정 실리콘 태양전지를 위한 열처리 공정에 대한 연구를 수행하였다. 고속 열처리 공정이 가능한 RTP 를 사용하여 다결정 실리콘 태양전지의 효율 향상에 요구되는 PECVD $SiN_x$ 반사방지막을 이용한 결정 결함의 수소화 효과를 극대화하는 동시에 양산 가능한 screen-printed contacts 의 특성 (FF >0.76) 올 최적화함으로써 다결정 실리콘 태양전지의 변환 효율을 $15.9\%$까지 향상시킬 수 있었다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1991년도 하계학술대회 논문집
• /
• pp.162-165
• /
• 1991

Oxygen behaviors in CZ-silicon wafer, grown by the Lucky Advanced Materials Inc. that is a pioneer of silicon material industries in Korea, were investigated to simulate effects on the device performance of oxygen, neglecting the effect of other impurity content, defects and thermal history. Silicon wafers were annealed through simulated 16K SRAM thermal cycle. As initial oxygen concentration increased up to 16.7ppma the amount of oxygen precipitation increased up to 10.6ppma and the bulk microdefect density increased up to $10.3{\times}10^3/mm^2$, but the depth of the denuded zone decreased to $5.0{\mu}m$

• E2M - 전기 전자와 첨단 소재
• /
• 제7권2호
• /
• pp.94-99
• /
• 1994

The purpose of this work is to investigate the interface characteristics of hydrogenated amorphous silicon thin films prepared by PECVD and photo-induced CVD and to examine the annealing effects of ultraviolet irradiation on hydrogenated amorphous silicon thin films which were degraded by visible light illumination. The interface layer thickness of films deposited by photo-induced CVD was about 600-900.angs. while that by PECVD was about 1000-1300.angs.. These results can show that the quality of interface layer in photo induced CVD film is better than that in PECVD sample. The electrical properties are improved by ultraviolet irradiation on visible light soaked a-Si:H films using photo-CVD light sources, probably due to the fact that UV generates phonons in a-Si:H films and anneal the meta stable defects.

• 마이크로전자및패키징학회지
• /
• 제9권4호
• /
• pp.17-23
• /
• 2002

최근 반도체 소자의 고속화 및 고집적화에 따라 배선 패턴이 미세화 되고 다층의 금속 배선 공정이 요구됨에 따라 단차를 줄이고 표면을 광역 평탄화 시킬 수 있는 STI-CMP 공정이 도입되었다. 그러나, STI-CMP 공정이 다소 복잡해짐에 따라 질화막 잔존물, 찢겨진 산화막 결함들과 같은 여러 가지 공정상의 문제점들이 심각하게 증가하고 있다. 본 논문에서는 이상과 같은 CMP 공정 결함들을 줄이고, STI-CMP 공정의 최적 조건을 확보하기 위해 트렌치 깊이와 STI-fill 산화막 두께가 리버스 모트 식각 공정 후, 트랜치 위의 예리한 산화막의 취약함과 STI-CMP공정 후의 질화막 잔존물 등과 같은 결함들에 미치는 영향에 대해 연구하였다. 실험결과, CMP 공정에서 STI-fill의 두께가 얇을수록, 트랜치 깊이가 깊을수록 찢겨진 산화막의 발생이 증가하였다. 트랜치 깊이가 낮고 CMP 두께가 높으면 질화막 잔존물이 늘어나는 반면, 트랜치 깊이가 깊어 과도한 연마가 진행되면 활성영역의 실리콘 손상을 받음을 알 수 있었다

• 한국재료학회지
• /
• 제34권2호
• /
• pp.111-115
• /
• 2024

Silicon carbide (SiC) has emerged as a promising material for next-generation power semiconductor materials, due to its high thermal conductivity and high critical electric field (~3 MV/cm) with a wide bandgap of 3.3 eV. This permits SiC devices to operate at lower on-resistance and higher breakdown voltage. However, to improve device performance, advanced research is still needed to reduce point defects in the SiC epitaxial layer. This work investigated the electrical characteristics and defect properties using DLTS analysis. Four deep level defects generated by the implantation process and during epitaxial layer growth were detected. Trap parameters such as energy level, capture-cross section, trap density were obtained from an Arrhenius plot. To investigate the impact of defects on the device, a 2D TCAD simulation was conducted using the same device structure, and the extracted defect parameters were added to confirm electrical characteristics. The degradation of device performance such as an increase in on-resistance by adding trap parameters was confirmed.

• 한국전기전자재료학회논문지
• /
• 제24권7호
• /
• pp.525-531
• /
• 2011

In this paper, experimental analyses have been performed to compare the electrical characteristics of n channel LT(low temperature) and HT(high temperature) poly-Si TFTs(polycrystalline silicon thin film transistors) on quartz substrate according to activated step annealing. The size of the particles step annealed at low temperature are bigger than high temperature poly-Si TFTs and measurements show that the electric characteristics those are transconductance, threshold voltage, electric effective mobility, on and off current of step annealed at LT poly-Si TFTs are high more than HT poly-Si TFT's. Especially we can estimated the defect in the activated grade poly crystalline silicon and the grain boundary of LT poly-Si TFT have more high than HT poly-Si TFT's due to high off electric current. Even though the size of particles of step annealed at low temperature, the electrical characteristics of LT poly-Si TFTs were investigated deterioration phenomena that is decrease on/off current ratio depend on high off current due to defects in active silicon layer.

• Rapid Communication in Photoscience
• /
• 제4권3호
• /
• pp.54-58
• /
• 2015

Under the condition of femtosecond impulsive nonlinear optical irradiation, the bright and narrowed blue emission of silicon nanocrystal was observed. This synthetic method produced very small (~ 4 nm) oxide-capped silicon nanocrystal having probably ultra small emitting core (~ 1 nm) inferred from luminescence. By controlling the stirring condition, very high efficiencies of luminescence ( 4 fold higher) were obtained compared with the other conventional femtosecond laser fragmentation methods, which was attributed to the differences in hydration shell structure during the femtosecond laser induced irreversible phase transition reaction. When we properly adjusted the irradiation times of the white light continuum and stirring condition, very homogeneous luminescent silicon nanocrystal bands having relatively sharp lineshape were obtained, which can be attributable to the luminescent core site isolated and free from the surface defects.