| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 148643 | Chemical Engineering Journal | 2013 | 8 Pages |
A process that used chemical vapor deposition (CVD) from the mixture of trichlorosilane (SiHCl3) and silicon tetrachloride (SiCl4) for the production of polysilicon granules in a fluidized bed reactor (FBR) was studied. The effects of the reaction temperature (800–1200 °C), molar ratio of H2 to SiHCl3 and SiCl4, and SiHCl3 fraction in the mixture of SiHCl3 and SiCl4 (0–100%) were studied. The reactant gas was analyzed by a gas chromatography (GC). The surface morphology of the product particles were analyzed by scanning electron microscopy. Well grown product particles were obtained. The reaction temperature and reactant composition significantly affected the Si yield and the amount of produced SiCl4 per kg deposited Si. The results showed that zero net by-production of SiCl4 could be realized by using the mixture of SiHCl3 and SiCl4 as reactant in a FBR while a satisfactory Si yield was remained. A suitable reaction condition for this was 1200 °C and molar ratio H2/SiHCl3/SiCl4 was 16/0.5/0.5. The corresponding one-through SiHCl3 conversion and Si yield were 21.1% and 9.6%, respectively, which were higher than the improved Siemens technology using pure SiHCl3.
► A process that produced Si from the mixture SiHCl3 and SiCl4 in FBR was studied. ► By-production of SiCl4 was completely suppressed by recycling by-produced SiCl4. ► Suitable conditions were 1200 °C and H2/SiHCl3/SiCl4 = 16/0.5/0.5. ► Corresponding one-through SiHCl3 conversion and Si yield were 30% and 9%, respectively.
