• E2M - 전기 전자와 첨단 소재
• /
• 제10권5호
• /
• pp.473-480
• /
• 1997

Surface passivation using glass powders results in good reliability for high voltage silicon power devices. In this paper Zinc borosilicate glass and Lead borosilicate glass were prepared for the purpose of passivating, and a deposition technique of glass films on the silicon surface by electrophoresis in which acetone is used as a suspension medium has been investigated. Their physical properties were compared using DTA, SEM, XRD, as a function of firing temperature, I can get the fine films of 22${\mu}{\textrm}{m}$ thickness with Lead borosilicate glass under 300 volts applied, 3 minutes and $700^{\circ}C$ firing temperature. Also I can get the fine films of 17${\mu}{\textrm}{m}$ thickness with Zinc borosilicate glass under same conditions. As a result of investigation of glass films from which glass layer was removed by placing it in HCl, it has been found that pre-firing and annealing play an important role to achieve uniform and fine glass deposition films. And also it was found that relative dielectric constant is independence of frequency.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
• /
• pp.269-270
• /
• 2005

A hybrid passivation method using parylene and silicon dioxide combination layer for a flexible organic light emitting diode (FOLED) was applied on a polycarbonate substrate. A parylene coating by vapor polymerization method is a highly effective passivation process for the FOLED, and it applies all top surface and the edges of the FOLED device. In order to minimize the permeation of moisture and oxygen from the top surface of the device, an additional layer of silicon dioxide was deposited over the parylene coated layer. It was found that the water vapor transmittance rate (WVTR) of parylene (15 m-in-thickness) / SiO2 (0.3$\mu$m-in-thickness) combination layers deposited on polycarbonate film was decreased under the value of 10-3 g/m2day. The FOLED with the hybrid passivation showed remarkably longer lifetime characteristics in the ambient conditions than the non-passivated FOLED. The lifetime of the passivated FOLED was 400 hours and it was more than ten times over the lifetime of the convectional non-passivated FOLED.

• 한국재료학회지
• /
• 제23권1호
• /
• pp.35-40
• /
• 2013

In this study, the influence on the surface passivation properties of crystalline silicon according to silicon wafer thickness, and the correlation with a-Si:H/c-Si heterojunction solar cell performances were investigated. The wafers passivated by p(n)-doped a-Si:H layers show poor passivation properties because of the doping elements, such as boron(B) and phosphorous(P), which result in a low minority carrier lifetime (MCLT). A decrease in open circuit voltage ($V_{oc}$) was observed when the wafer thickness was thinned from $170{\mu}m$ to $50{\mu}m$. On the other hand, wafers incorporating intrinsic (i) a-Si:H as a passivation layer showed high quality passivation of a-Si:H/c-Si. The implied $V_{oc}$ of the ITO/p a-Si:H/i a-Si:H/n c-Si wafer/i a-Si:H/n a-Si:H/ITO stacked layers was 0.715 V for $50{\mu}m$ c-Si substrate, and 0.704 V for $170{\mu}m$ c-Si. The $V_{oc}$ in the heterojunction solar cells increased with decreases in the substrate thickness. The high quality passivation property on the c-Si led to an increasing of $V_{oc}$ in the thinner wafer. Short circuit current decreased as the substrate became thinner because of the low optical absorption for long wavelength light. In this paper, we show that high quality passivation of c-Si plays a role in heterojunction solar cells and is important in the development of thinner wafer technology.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2010년도 추계학술대회 초록집
• /
• pp.55.2-55.2
• /
• 2010

최근 태양전지에 대한 연구가 본격적으로 진행 중인 가운데 Local back contact 태양전지에 대한 연구가 새로운 이슈로 떠오르고 있다. LBC 구조의 태양전지는 후면 passivation에 대한 최적화 공정이 가장 중요하다. 후면 passivation으로 사용되는 물질로는 $SiO_2$, SiNx, $Al_2O_3$ 등의 산화막이 대표적이다. 본 연구에서는 LBC 구조 태양전지의 후면 passivation 박막으로 사용되는 $SiO_2$ 산화막의 공정가변에 따른 박막의 특성을 비교 분석하였다. $SiO_2$ 성장은 RTP를 사용하였다. 성장 온도 $850^{\circ}C$의 온도에서 진행하였으며, 4L/min의 $O_2$분위기에서 진행하였다. 공정 시간 5분 일 때 12.5nm, 15분 일 때 21.7nm의 두께의 박막을 성장 시킬 수 있었다. Carrier lifetime 확인 결과 박막의 두께가 얇을수록 lifetime이 향상함을 확인 할 수 있었고, C-V 측정을 통한 charge 비교를 통해 두께가 얇은 박막 일수록 더 적은 positive charge를 갖고있는 것을 확인 할 수 있었으며 이를 통해 passivation 효과가 우수함을 확인 할 수 있었다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
• /
• pp.126-129
• /
• 2000

This paper describes on the fabrication of a SOI substrate by SDB technology and electrochemical etch-stop. The surface of the thinned SDB SOI substrate is more uniform than that of grinding or polishing by mechanical method, and this process was found to be very accurate method for SOI thickness control. During electrochemical etch-stop, leakage current versus voltage curves were measured for analysis of the open current potential (OCP) point, the passivation potential (PP) point and anodic passivation potential. The surface roughness and the controlled thickness selectivity of the fabricated a SDB SOI substrate were evaluated by using AFM and SEM, respectively.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2000년도 영호남학술대회 논문집
• /
• pp.301-306
• /
• 2000

This paper describes on the fabrication of a SOI substrate by SDB technology and electrochemical etch-stop. The surface of the thinned SDB SOI substrate is more uniform than that of grinding or polishing by mechanical method, and this process was found to be a very accurate method for SOI thickness control. During electrochemical etch-stop, leakage current versus voltage curves were measured for analysis of the open current potential(OCP) point, the passivation potential(PP) point and anodic passivation potential. The surface roughness and the controlled thickness selectivity of the fabricated a SDB SOI substrate were evaluated by using AFM and SEM, respectively.

• 한국전기전자재료학회논문지
• /
• 제13권5호
• /
• pp.431-436
• /
• 2000

This paper describes on the fabrication of a SOI substrate by SDB technology and electrochemical etch-stop. The surface of the thinned SDB SOI substrate is more uniform than that of grinding or polishing by mechanical method and this process was found to be a very accurate method for SOI thickness control. During electrochemical etch-stop leakage current versus voltage curves were measured for analysis of the open current potential(OCP) point the passivation potential(PP) point and anodic passivation potential. The surface roughness and the controlled thickness selectivity of the fabricated a SDB SOI substrate were evaluated by using AFM and SEM respectively.

• Bulletin of the Korean Chemical Society
• /
• 제12권5호
• /
• pp.540-544
• /
• 1991

Thin film being formed on the surface of cobalt in the early stage of electrochemically induced passivation was studied by the three-parameter ellipsometry. The growth of the passive film was complete in a few seconds from the onset of the passivating potential, and was followed by a slight decrease in the thickness in 4-40 seconds. The optical constants of the passive film changed gradually during the changes in the thickness. The thickness and the optical properties at the steady state of passivation depended on the potential of the electrode. From the coulometric data and the optical properties, the composition of the passive films was deduced to be close to those of CoO, ${Co_3}{O_4}$ and ${Co_2}{O_3}$ depending on the potential. Cathodic reduction in the presence of EDTA was found to be an efficient way to obtain film-free reference surface of cobalt.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
• /
• pp.964-967
• /
• 2002

The effectiveness of silicon nitride SiNx surface passivation is investigated and quantified. This study adopted single-layer antireflection (SLAR) coating of SiNx for efficiency improvement of solar cell. The silicon nitride films were deposited by means of plasma enhanced chemical vapor deposition (PECVD) in planar coil reactor. The process gases used were pure ammonia and a mixture of silane and helium. The thickness and the refractive index on the films were measured by ellipsometry and chemical bonds were determined by using an FT-IR equipment. This films obtained were analyzed in term of hydrogen content, refractive index for gas flow ratio $(NH_3/SiH_4)$, and efficiency of solar cell. The polycrystalline silicon solar cells passivated by silicon nitride shows efficiency above 12.8%.

• Nuclear Engineering and Technology
• /
• 제54권12호
• /
• pp.4693-4697
• /
• 2022

Parylene coating was adopted on CdZnTe (CZT) detector as a mechanical protection layer after wet passivation with hydrogen peroxide (H₂O₂) and ammonium fluoride (NH₄F). Wet chemical passivant lose their effectiveness when exposed to the ambient conditions for a long time. Parylene coating could protect the effectiveness of passivation, by mechanically blocking the exposure to the ambient conditions. Stability of CZT detector was tested with the measurement of leakage current density and response to radio-isotopes. When the enough thickness of parylene (>100 ㎛) is adopted, parylene is a promising protection layer thereby ensuring the performance and long-term stability of CZT detectors.