• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.55 no.12
• /
• pp.565-569
• /
• 2006

Plasma enhanced chemical vapor deposition(PECVD) is a well established technique for the deposition of hydrogenated film of silicon nitride (SiNx:H), which is commonly used as an antireflection coating as well as passivating layer in crystalline silicon solar cell. PECVD-SiNx:H films were investigated by varying the deposition and annealing conditions to optimize for the application in silicon solar cells. By varying the gas ratio (ammonia to silane), the silicon nitride films of refractive indices 1.85 - 2.45 were obtained. The film deposited at $450^{\circ}C$ showed the best carrier lifetime through the film deposition rate was not encouraging. The film deposited with the gas ratio of 0.57 showed the best carrier lifetime after annealing at a temperature of $800^{\circ}C$. The single crystalline silicon solar cells fabricated in conventional industrial production line applying the optimized film deposition and annealing conditions on large area substrate of size $125mm{\times}125mm$ (pseudo square) was found to have the conversion efficiencies as high as 17.05 %. Low cost and high efficiency silicon solar cells fabrication sequence has also been explained in this paper.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.29 no.8
• /
• pp.505-509
• /
• 2016

We have investigated the characteristics of amorphous silicon (a-Si) thin-film solar cell by inserting barrier layer. The conversion efficiency of a-Si thin-film solar cells on graphite substrate shows nearly zero because of the surface roughness of the graphite substrate. To enhance the performance of solar cells, the surface morphology of the back side were modified by changing the barrier layer on graphite. The surface roughness of graphite substrate with the barrier layer grown by plasma enhanced chemical vapor deposition (PECVD) reduced from ~2 um to ~75 nm. In this study, the combination of the barrier layer on graphite substrate is important to increase solar cell efficiency. We achieved ~ 7.8% cell efficiency for an a-Si thin-film solar cell on graphite substrate with SiNx/SiOx stack barrier layer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.04a
• /
• pp.57-58
• /
• 2008

Microcrystalline (${\mu}c$) silicon thin films were prepared on glass by plasma-enhanced-chemical-vapor-deposition (PECVD) at various substrate temperature, and dilution ratio of $H_2$ with $SiH_4$. The structural and optical properties of. the ${\mu}c-Si$ thin films were investigated using XRD and UV-VIS spectrophotometer. The ${\mu}c-Si$ thin film with 42 nm grain size was grown at optimal condition of 2.5 Torr, spacing between electrodes of 3cm, deposition time of 3000s, RF power of 200W, substrate temperature of $350^{\circ}C$, $SiH_4$ ($20%SiH_4$+80%He) of 50sccm, and $H_2$ of 100sccm.

• Journal of the Korean Ceramic Society
• /
• v.38 no.4
• /
• pp.365-369
• /
• 2001

플라즈마 화학증착법(PECVD)에 의해 실리콘 (100) 기판 위에 3C-SiC막을 증착하였다. 증착반응시 유입가스비, R$_{x}$[=CH$_4$/(CH$_4$+H$_2$)]에 따른 증착막의 결정성에 대해 검토하였다. 증착된 3C-SiC막의 결정성은 R$_{x}$ 값이 감소할수록 더욱 향상되었으며, 형성된 결정상은 (111) 면으로 최대의 우선배향성을 가졌다. Nanoindentation 방법을 이용하여 3C-SiC막의 압입깊이에 따른 경도 및 탄성계수를 측정하였으며, 유입가스비(R$_{x}$)의 변화에 따라서 막의 경도 및 탄성계수가 뚜렷이 변화하였다.

• The Korean Journal of Ceramics
• /
• v.4 no.1
• /
• pp.9-14
• /
• 1998

Diamond-like carbon(DLC) films were deposited on buffer-layered ZnS substrates by radio frequency plasma enhanced chemical vapor deposition(RF-PECVD) method. Ge and GeC buffer layera were used between DLC and ZnS substrates to promote the adhesion of DLC on ZnS substrates. Ge buffer layers were sputter deposited by RF magnetron sputtering and $GeC^1$ buffer layers were deposited by same method except using acetylene reactive gas. The relatinship between film properties and deposition conditions was investigated using gas pressure, RF power and dc bias voltage as PECVD parameters. The hardness of DLC films were measured by micro Vickers hardness test and the adhesion of DLC films on buffer-layered ZnS substrates were studied by Sebastian V stud pull tester. The optical properties of DLC films on butter-layered ZnS substrates were characterized by ellipsometer and FTIR spectroscopy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.11a
• /
• pp.276-279
• /
• 2004

Plasma enhanced chemical vapor deposition (PECVD) of silicon nitride (SiN) is a proven technique for obtaining layers that meet the needs of surface passivation and anti-reflection coating. In addition, the deposition process appears to provoke bulk passivation as well due to diffusion of atomic hydrogen. This bulk passivation is an important advantage of PECVD deposition when compared to the conventional CVD techniques. A further advantage of PECVD is that the process takes place at a relatively low temperature of 300t, keeping the total thermal budget of the cell processing to a minimum. In this work SiN deposition was performed using a horizontal PECVD reactor system consisting of a long horizontal quartz tube that was radiantly heated. Special and long rectangular graphite plates served as both the electrodes to establish the plasma and holders of the wafers. The electrode configuration was designed to provide a uniform plasma environment for each wafer and to ensure the film uniformity. These horizontally oriented graphite electrodes were stacked parallel to one another, side by side, with alternating plates serving as power and ground electrodes for the RF power supply. The plasma was formed in the space between each pair of plates. Also this paper deals with the fabrication of multicrystalline silicon solar cells with PECVD SiN layers combined with high-throughput screen printing and RTP firing. Using this sequence we were able to obtain solar cells with an efficiency of 14% for polished multi crystalline Si wafers of size 125 m square.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.07a
• /
• pp.328-331
• /
• 2000

Carbon nanotube(CNT) was successfully grown on Ni-W alloyed substrate by applying PECVD technique(Plasma Enhanced Chemical Vapor Deposition). As a catalyst, Ni-W alloyed substrate was prepared by mechanical alloying method. In order to find the optimum growth condition, initially two different types of gas mixtures such ac $C_2$H$_2$-H$_2$and $C_2$H$_2$-MH$_3$were systematically investigated by adjusting results on the mixing ratio in temperature range of 500 to 80$0^{\circ}C$. In this work, we will report the preliminary results on the CNT processed by PECVD, which were characterized by XRD, SEM and TEM. Finally we will evalute the effect on CNT growth by changing many processing parameters, such as typical gas, mixing ratio between 2 mixture, plasma power and etc.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.148-148
• /
• 2008

Low-k dielectric materials are an alternative plan to improve the signal propagation delay, crosstalk, dynamic power consumption due to resistance and parasitic capacitance generated the decrease of device size. Now, various materials is studied for the next generation. Diethoxymethlysiliane (DEMS) precursor using this study has two ethoxy groups along with one methyl group attached to the silicon atoms. SiCOH thin films were deposited on p-type Si(100) substrate by Plasma Enhanced Chemical Vapor Deposition (PECVD) using DEMS. In this study, we studied the effect of oxygen($O_2$) flow rate for DEMS to characteristics of thin films. The characteristics of thin films deposited using DEMS and $O_2$ evaluated through refractive index, dielectric constant(k), surface roughness, I-V(MIM:Al / SiCOH / Ag), C-V(MIM), deposition rate.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1999.07a
• /
• pp.123-123
• /
• 1999

Amorphous hydrogenated silicon carbide (a-SiC:H) films were deposited at the temperature of 40$0^{\circ}C$ using plasma enhanced chemical vapor deposition. The a-SiC:H films were characterized by x-ray photoelectron spectroscopy (XPS) and nanoindentation method. By increasing the plasma power from 20W to 160W, the oxygen content of the a-SiC:H films were observed to decrease from 12.1% to 4.4%. On the other hand, the plasma power did not affect the ratio of carbon to silicon in our experiment where the 1, 3-disilabutane was used as the precursor. Microhardness of the films was observed to increase as the plasma power increased, while the elastic modulus was observed to gave a maximum value at the plasma power of 80W. Microhardness of the film is thought to be strongly affected by the content of adventitious oxygen in the film and it is concluded that the hardness of the film can be improved by increasing the plasma power.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2015.08a
• /
• pp.131.2-131.2
• /
• 2015

마이크로웨이브를 이용한 플라즈마는 효율적인 전자가열이 가능하며, 낮은 이온에너지를 가지는 고밀도 플라즈마를 생성시킬 수 있다는 장점이 있다. 최근 산화물 반도체 및 대화면 디스플레이 장치내 소자의 보호막 증착용으로 저온 PECVD (Plasma Enhanced Chemical Vapor Deposition) 공정 및 장치의 필요성에 따라 마이크로웨이브를 이용한 PECVD 장치가 주목 받고 있다. 본 연구에서는 실리콘 나이트라이드 공정 장치 개발을 위한 2차원 시뮬레이션 모델을 완성하였다. Global modeling을 이용하여 확보한 Chemical reaction data에 대한 검증을 하였다. Maxwell's equation, continuity equation, electromagnetic wave equation 등을 이용하여 Microwave의 파워 및 압력에 따른 전자 밀도, 전자 온도등의 플라즈마 변수의 변화를 관찰하였다. 또한 Navier Stokes equation을 추가하여 챔버 내의 Gas flow의 흐름을 고려한 시뮬레이션을 진행하여 분석하였다.