• 한국전기전자재료학회논문지
• /
• 제27권3호
• /
• pp.137-140
• /
• 2014

With the recent advent of through silicon via (TSV) technology, wafer level-TSV interconnection become feasible in high volume manufacturing. To increase the manufacturing productivity, it is required to develop equipment for backside passivation layer deposition for TSV wafer bonding process with high deposition rate and low film stress. In this research, we investigated the relationship between process parameters and the induced wafer stress of PECVD silicon nitride film on 300 mm wafers employing statistical and artificial intelligence modeling. We found that the film stress increases with increased RF power, but the pressure has inversely proportional to the stress. It is also observed that no significant stress change is observed when the gas flow rate is low.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
• /
• pp.220-223
• /
• 1996

Mechanical properties of Plasma-Enhanced Chemical Vapor Deposited (PECVD) silicon nitride thin film was studied to determine the feasibility of the film as a passivation layer over the aluminum bonding areas of integrated circuit chips. Ultimate strain of the films in thicknesses of about 5 k${\AA}$ was measured using four-point bending method. The ultimate strain of these films was constant at about 0.2% regardless of residual stress. Intrinsic and residual stresses of these films were measured and compared with thermal shock and cycling test results. Comparison of the results showed that more tensile films were more susceptible to crack- induced failure.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
• /
• pp.1127-1130
• /
• 2003

The characteristics of silicon nitride films deposited in a planar coil reactor using a simple high-density inductively coupled plasma chemical vapor deposition technique have been investigated. The process gases used during silicon nitride deposition cycle were pure nitrogen and a mixture of silane and helium. It has been pointed out that the strong H-atom released from the growing SiN film and Si-N bond healing are responsible for the improved electrical and passivation properties of SiN.

• 한국표면공학회지
• /
• 제31권1호
• /
• pp.54-62
• /
• 1998

In this study, the behaviorof ion nitriding of AISI 304 stainless steel was investigated using plasma ion nitriding system. The characteristics of ion nitriding, and their micsoctrucyures, and physical properties were investigated as a function of process parmeteds. important conclusions can be summarzied as follows. Firstly, it was found that growth of nitride layer in ion nitriding are mainly affected by N2 partial pressures and nitriding temperatures for AISI 304 stainless steel. The $N_2$<\TEX> partial pressure plays on important role in ion nitriding since it determiness the incoming flux of nitrogen species onto specimen surface. Nitriding thmprrature is also important besauseit determines the diffusion rates of nitrogen through nitride layers. While both parameters affects the characteristics rateding are controlled by nitridingen diffusion nitration profiles of N and alloying elements such as Cr and Ni are observed through niride layers. Secondly, nitride layer consists of the upper white laywe having various nitride phases and the underneath diffusion layers. The thickness of white layer increases with $N_2$<\TEX> partial pressures and nitriding temperatures. The thinkness of diffusion layer is increasting nitriding temperatures. Finally, nitriding of stainless steels steel show slighly low their corrsionce prorerties. However, passivation properties, which is normally observed in stainless steels, were still observed aftre ion nitriding.

• 한국태양에너지학회 논문집
• /
• 제33권2호
• /
• pp.11-17
• /
• 2013

Silicon nitride($SiN_x:H$) deposited by radio frequency plasma enhanced chemical vapor deposition(RF-PECVD) is commonly used for anti-reflection coating and passivation in crystalline silicon solar cell fabrication. In this paper, characteristics of the deposited silicon nitride was studied with change of working pressure, deposition temperature, gas ratio of $NH_3$ and $SiH_4$, and RF power during deposition. The deposition rate, refractive index and effective lifetime were analyzed. The (100) p-type silicon wafers with one-side polished, $660-690{\mu}m$, and resistivity $1-10{\Omega}{\cdot}cm$ were used. As a result, when the working pressure increased, the deposition rate of SiNx was increased while the effective life time for the $SiN_x$-deposited wafer was decreased. The result regarding deposition temperature, gas ratio and RF power changes would be explained in detail below. In this paper, the optimized condition in silicon nitride deposition for silicon solar cell was obtained as 1.0 Torr for the working pressure, $400^{\circ}C$ for deposition temperature, 500 W for RF power and 0.88 for $NH_3/SiH_4$ gas ratio. The silicon nitride layer deposited in this condition showed the effective life time of > $1400{\mu}s$ and the surface recombination rate of 25 cm/s. The crystalline silicon solar cell fabricated with this SiNx coating showed 18.1% conversion efficiency.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
• /
• pp.430-430
• /
• 2012

The surface recombination velocity of the silicon solar cell could be reduced by passivation with insulating layers such as $SiO_2$, SiNx, $Al_2O_3$, a-Si. Especially, the aluminium oxide has advantages over other materials at rear surface, because negative fixed charge via Al vacancy has an additional back surface field effect (BSF). It can increase the lifetime of the hole carrier in p-type silicon. The aluminium oxide thin film layer is usually deposited by atomic layer deposition (ALD) technique, which is expensive and has low deposition rate. In this study, ICP-assisted reactive magnetron sputtering technique was adopted to overcome drawbacks of ALD technique. In addition, it has been known that by annealing aluminium oxide layer in nitrogen atmosphere, the negative fixed charge effect could be further improved. By using ICP-assisted reactive magnetron sputtering technique, oxygen to nitrogen ratio could be precisely controlled. Fabricated aluminium oxy-nitride (AlON) layer on silicon wafers were analyzed by x-ray photoelectron spectroscopy (XPS) to investigate the atomic concentration ratio and chemical states. The electrical properties of Al/($Al_2O_3$ or $SiO_2/Al_2O_3$)/Si (MIS) devices were characterized by the C-V measurement technique using HP 4284A. The detailed characteristics of the AlON passivation layer will be shown and discussed.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제12권4호
• /
• pp.449-457
• /
• 2012

The program/erase (P/E) cyclic endurances including bias temperature instability (BTI) behaviors of Metal-$Al_2O_3$-Nitride-Oxide-Semiconductor (MANOS) memories are investigated in comparison with those of Semiconductor-Oxide-Nitride-Oxide-Semiconductor (SONOS) memories. In terms of BTI behaviors, the SONOS power-law exponent n is ~0.3 independent of the P/E cycle and the temperature in the case of programmed cell, and 0.36~0.66 sensitive to the temperature in case of erased cell. Physical mechanisms are observed with thermally activated $h^*$ diffusion-induced Si/$SiO_2$ interface trap ($N_{IT}$) curing and Poole-Frenkel emission of holes trapped in border trap in the bottom oxide ($N_{OT}$). In terms of the BTI behavior in MANOS memory cells, the power-law exponent is n=0.4~0.9 in the programmed cell and n=0.65~1.2 in the erased cell, which means that the power law is strong function of the number of P/E cycles, not of the temperature. Related mechanism is can be explained by the competition between the cycle-induced degradation of P/E efficiency and the temperature-controlled $h^*$ diffusion followed by $N_{IT}$ passivation.

• 전기화학회지
• /
• 제27권1호
• /
• pp.8-14
• /
• 2024

오스테나이트계 스테인리스강은 내식성 및 성형성이 양호하여 다양한 분야에 적용되며, 구리계의 합금을 용가재로 하는 브레이징을 통하여 다양한 형상의 제품으로 가공되어 활용되고 있다. 이때, 구리 기반의 용가재와 스테인리스강의 계면에서 갈바닉 셀을 형성하여 부식을 촉진할 수 있으며, 확산을 통해 스테인리스강에 고용 시 형성되는 구리 과다 영역(Cu-rich region)은 공식 발생의 기점이 되어 내식성을 저하시킨다. 본 연구에서는 브레이징이 적용된 스테인리스강의 내식성을 개선하고자, AISI 316L 스테인리스강에 암모니아 가스를 이용한 질화처리를 적용하였다. 질화처리한 시편은 처리 온도가 증가함에 따라 두께가 증가하고 표면 경도가 높아졌다. 동전위분극시험을 통해 내식성을 평가한 결과 질화층 내 고용된 질소의 용출 및 부동태 거동으로 모재대비 내식성이 개선되었지만 처리온도가 높아 크롬질화물(CrN) 분율이 증가하는 경우 내식성이 감소하였다.

• 한국전기전자재료학회논문지
• /
• 제18권7호
• /
• pp.662-666
• /
• 2005

Silicon nitride $(SiN_x)$ film is a promising material for anti-reflection coating and passivation of multicrystalline silicon (me-Si) solar cells. In this work, a plasma-enhanced chemical vapor deposition (PECVD) system with batch-type reactor tube was used to prepare highly robust $SiN_x$ films for screen-printed mc-Si solar cells. The Gas flow ratio, $R=[SiH_4]/[NH_3]$, in a mixture of silane and ammonia was varied in the range of 0.0910.235 while maintaining the total flow rate of the process gases to 4,200 sccm. The refractive index of the $SiN_x$ film deposited with a gas flow ratio of 0.091 was measured to be 2.03 and increased to 2.37 as the gas flow ratio increased to 0.235. The highest efficiency of the cell was $14.99\%$ when the flow rate of $SiH_4$ was 350 sccm (R=0.091). Generally, we observed that the efficiency of the mc-Si solar cell decreased with increasing R. From the analysis of the reflectance and the quantum efficiency of the cell, the decrease in the efficiency was shown to originate mainly from an increase in the surface reflectance for a high flow rate of $SiH_4$ during the deposition of $SiN_x$ films.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
• /
• pp.364.1-364.1
• /
• 2014

고효율 태양전지로 가기 위해서는 태양전지의 후면 패시베이션은 중요한 역할을 한다. 후면 패시베이션 막으로 사용되는 $Al_2O_3$ 막은 $Al_2O_3/Si$ 계면에서 높은 화학적 패시베이션과 Negative Fixed Charge를 가지고 있어 적합한 Barrier막으로 여겨진다. 하지만 이후에 전면 Metal paste의 소성 공정에 의해 $800^{\circ}C$이상 온도를 올려주게 됨에 따라 $Al_2O_3$ 막 내부에 결합되어 있던 수소들이 방출되어 blister가 생성되고 막 질은 떨어지게 된다. 우리는 blister가 생성되는 것을 방지하기 위한 방법으로 PECVD 장비로 SiNx를 증착하는 공정 중에 $N_2O$ 가스를 첨가하여 SiON 막을 증착하였다. SiON막은 $N_2O$가스량을 조절하여 막의 특성을 변화시키고 변화에 따라 소성시 막에 미치는 영향에 대하여 조사하였다. 공정을 위해 $156{\times}156mm2$, $200{\mu}m$, $0.5-3.0{\Omega}{\cdot}cm$ and p-type 단결정 실리콘 웨이퍼를 사용하였고, $Al_2O_3$ 막을 올리기 전에 RCA Cleaning 실행하였다. ALD 장비를 통해 $Al_2O_3$ 막을 10nm 증착하였고 RF-PECVD 장비로 SiNx막과 SiON막을 80nm 증착하였다. 소성로에서 $850^{\circ}C$ ($680^{\circ}C$) 5초동안 소성하고 QSSPC를 통해 유효 반송자 수명을 알아보았다.