Study of Optoelectronic Properties of doped Silicon Films by TBP and TMB

• Main Authors: Yi-cheng Lai, 賴宜呈
• Other Authors: Lu-Sheng Hong
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/32864376097241662161

碩士 === 國立臺灣科技大學 === 材料科技研究所 === 96 === In this thesis, we deposited doped thin silicon films using a parallel plate PECVD system. We deposited doped thin silicon films and thin film a-Si:H solar cell on glasses using tertiarybutylphosphine (TBP) and trimethylboron (TMB) as the dopant precursors of n-type and p-type layers, respectively. The optical and electrical properties of n-a-Si:H, p-a-Si:H, p-a-SiC:H and p-uc-Si:H films have been investigated. The dark conductivity and optical gap of the n-a-Si:H was 3.7×10-3 S/cm and 1.7 eV respectively under a 0.5% TBP doping ratio. The dark conductivity of the p-a-Si:H was 8×10-5 S/cm under 1% TMB doping ratio. Because the optical transmission of the p-a-Si:H was not good as a window layer for solar cell, we deposited a-SiC:H by adding CH4. The optical gap of the p-a-SiC:H was 2 eV when [CH4]/[SiH4]=0.6, while the carbon incorporation amount was about 20%. However, the dark conductivity decreased sharply. Micro-crystalline p type layers by increasing [H2]/[SiH4] feeding ratio up to 80 was done. The result showed that the dark conductivity was decreased to 3×10-2 S/cm for a 80 nm-thick p type microcrystalline layer, yet the value decreased to 10-6 for order when it thickness was decreased to 30 nm. A p-i-n cell was fabricated, which showed a Voc of about 0.53 V and Isc of 0.9 mA, the efficiency of the thin film a-Si:H solar cell is 0.24%. We will use laser scribing and modify the deposition parameter of the p-layer to improve the efficiency of solar cell.