Insulating material for polycrystalline silicon hydrogenation furnace

Abstract

The invention relates to the field of photovoltaics or semiconductor, in particular to an insulating material for a polycrystalline silicon hydrogenation furnace. The insulating material is characterized in that the formula of the insulating material comprises 80 to 99 percent of silicon nitride and 1 to 20 percent of stabilizer. Because the silicon nitride is a high-temperature-resistant and corrosion-resistant gas, the silicon nitride does not react with corrosive gas, such as H2, HCl, SiHCl3, SiCl4 and the like, under the condition of high temperature. Thus, the insulating material can effectively prevent a conducting material, such as stripped carbon felt and the like, in a heat-insulating cage from connecting an electrode with a chassis not to cause a short-circuit phenomenon, and isolate the electrode from high temperature in the furnace so as to avoid the digitalization of a spacer at the bottom of the electrode caused by high temperature; therefore, safety accidents, such as hydrogen leakage and even explosion of the hydrogenation furnace and the like, are prevented. In addition, the insulating material can also be used in a reducing furnace or synthesizing tower under polycrystalline silicon production environment so as to conduct the function of heat insulation, corrosion resistance and high temperature resistance, such as electrode washer, valve core and the like.

Description

technical field [0001] The invention relates to the fields of photovoltaics or semiconductors, in particular to an insulating material for a polycrystalline silicon hydrogenation furnace. Background technique [0002] Polysilicon is the most important photovoltaic material, the main material of integrated circuit silicon substrate, new environmentally friendly energy solar cells, and the direct raw material for the production of monocrystalline silicon. There are many ways to produce polysilicon. At present, polysilicon manufacturers at home and abroad mainly use the improved Siemens method (closed-loop trichlorosilane reduction method) to produce polysilicon. The improved Siemens method is to use chlorine and hydrogen to synthesize hydrogen chloride, hydrogen chloride and silicon powder to synthesize trichlorosilane at a certain temperature, and then separate and rectify trichlorosilane for purification, and the purified trichlorosilane is carried out in a polysilicon reduc...

AI Technical Summary

Problems solved by technology

In addition, at high temperature, SiHCl 3 and H 2 The silicon generated by the reaction is deposited on the graphite rod or the inner wall of the heat insulation cage at a higher temperature. Due to the existence of thermal stress, the generated silicon or silicon carbide will stick to part of the graphite material and peel off from the graphite rod in the form of large scales. Most of these substances Falling on the electrode that has lost the protection of the quartz ring, the electrode will be connected to the graphite of the chassis, causing a short circuit and affecting the normal operation of the high-temperature hydrogenation furnace