Title :
Closed recycle CVD process for mass production of SOG-Si from MG-Si
Author :
Noda, Suguru ; Hagiwara, Kazuki ; Ichikawa, Osamu ; Tanabe, Katsuaki ; Yahiro, Takashi ; Ohkawa, Hiroshi ; Osawa, Toshio ; Komiyama, Hiroshi
Author_Institution :
Dept. of Chem. Syst. Eng., Tokyo Univ., Japan
Abstract :
"CVD Process with Closed Gas Recycling" is proposed for mass production of SOG-Si from MG-Si. By combining chlorosilane synthesis in the reaction of MG-Si and HCl and Si-CVD from chlorosilanes, a closed system with ideal Si conversion ratio of 100 % can be realized with little emission of chloride pollutants. Based on thermodynamic investigation, operating temperatures were set below 900 K for Si etching and above 1200 K for Si-CVD. Si etching showed time dependent natures due to the activation of Si surface, and the rate of activated surfaces was in the order of 1 μm/min (623- 723 K. 0.9×105 Pa, 3.3- 10 mol% HCl/H2). Si growth rate by CVD was also in the same order (1323- 1473 K, 0.1- 1×105 Pa, 0.1- 9 mol% SiHCl3/H2 or SiCl4/H2), which was quantitatively explained by kinetic simulations. This process can be combined with layer transfer processes to form crystalline Si thin films.
Keywords :
CVD coatings; elemental semiconductors; etching; semiconductor thin films; silicon; solar cells; 0.1×105 to 1×105 Pa; 0.9×105 Pa; 1200 K; 1323 to 1473 K; 623 to 723 K; 900 K; MG-Si; SOG-Si; Si; Si etching; activated surfaces; chloride pollutants; chlorosilane synthesis; closed recycle CVD process; ideal Si conversion ratio; kinetic simulations; layer transfer processes; mass production; operating temperatures; Crystallization; Etching; Kinetic theory; Mass production; Pollution; Recycling; Semiconductor thin films; Surface contamination; Temperature; Thermodynamics;
Conference_Titel :
Photovoltaic Specialists Conference, 2002. Conference Record of the Twenty-Ninth IEEE
Print_ISBN :
0-7803-7471-1
DOI :
10.1109/PVSC.2002.1190520
