| The Siemens process was extensively applied to the production of polycrystallinesilicon. This study foucs on the temperature filed, flow filed and energy loss in theCVD reactor.The growth of Si from SiHCl3in H2by chemical vapor deposition （CVD） takesplace in the CVD reactor，it accompanies with momentum, heat, mass transferprocesses and chemical reaction. A good compromise between internal flow field andtemperature field uniformity has great influence on the energy consumption of CVDreactor. In this study, a new design of CVD reactor was provided. A different flowpattern formed due to setting a shield in the reactor. The shield divides the gas inletsand outlets into different zones compared with traditional reactor whose gas inlets andoutlets are in the same zone. Gas flow upwards after entering the reactor and havechemical vapor deposition reaction, then go across the top of the shield, finally flowout the outlets. This study focus on the design of shield structure in order to attaingood internal flow field and temperature field uniformity. According to the CFDsimulation, there is not the phenomenon of local temperature is too high, thetemperature of wall is lower than575℃, so the Si will not deposite on the wall, thereflection effect of wall could be preserved. According to set wall reflectivity asvariable, it could be found that the wall reflectivity has little influence for thetemperature field uniformity in the improved CVD reactor. The gas flow equably fromthe bottom up in the improved CVD reactor, it is good for the deposition of Si on theSi rods and preserves the rods’ equally growth.Compared improved CVD reactor with traditional CVD reactor, the wall energy lossof improved CVD reactor is14.6%lower than traditional CVD reactor. Lastly, thereaserch indicates the energy loss of Si production declined with the wall reflectivity’increase, so the cost of Si production and energy loss could decrease by increasing thewall reflectivity. |
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