Process for synthesizing guartz glass by vertical silicon tetrachloride vapor deposition

Abstract

The present invention discloses the vertical silicon tetrachloride vapor deposition process of synthesizing quartz glass. One vertical deposition furnace is designed, which includes chimney, closed furnace body, burner in the top of the furnace body, base rod standing inside the furnace body, deposition plane on the base rod and opposite to the burner, and lathe clamped to the lower part of the base rod. There may be several burners with several material feeding tubes each. The present invention makes it possible to produce quartz glass ingot with weight of 30-50 Kg and diameter of 250-500 mm in the deposition rate of 200-500 g / hr, 1-5 times higher than that of horizontal deposition furnace.

Description

technical field [0001] The invention relates to a method for synthesizing quartz glass by vapor phase deposition of silicon tetrachloride. Background technique [0002] For more than two decades, quartz glass has been produced using a horizontal CVD production process. In this process, the deposition furnace adopts a horizontal furnace. The base rod of the furnace is arranged horizontally, one end is located inside the furnace body, and a deposition mound surface is fixed to the end of the base rod. As shown in Figure 1, the furnace body is open. , where the middle part is a chimney, a burner is provided outside one end of the furnace body, and a base rod is pierced through the other end. Crystals formed. There are three problems in the installation of horizontal furnaces: one is that the foundation rods are set horizontally, and the weight and the length of the foundation rods increase as the deposition mound surface accepts the deposits from the burner, and the pressure ...

AI Technical Summary

Problems solved by technology

There are three problems in the installation of horizontal furnaces: one is that the foundation rods are set horizontally, and the weight and the length of the foundation rods increase as the deposition mound surface accepts the deposits from the burner, and the pressure and tension on the foundation rods are doubled growth, which in turn causes the self-weight fracture of the basic rod; the second basic rod traverses the temperature field from room temperature to 1500°C. Since deposition is a slow process, the basic rod is in such a temperature field for a long time, which will cause crystallization. Reduce the strength of the base rod to bear the weight, resulting in the breakage of the base rod, thus limiting the production of large-size, large-diameter quartz glass; thirdly, the horizontal furnace is open-type production, which has low furnace temperature, high energy consumption and low efficiency

Due to the problem of the deposition furnace, the quartz glass ingot produced by the horizontal process is generally 10-20 kg, the diameter is 150-180 mm, the deposition rate is 40-100 g / hour, light weight, small diameter and low efficiency

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