Method for producing synthetic quartz material for semiconductor mask

Abstract

The invention relates to a method for producing a synthetic quartz material for a semiconductor mask plate. The method comprises the following steps: (1) depositing a silicon source on a guide rod by adopting a vapor phase axial deposition method to obtain a low-density SiO2 loose body; wherein in the deposition process, the interior of the deposition cavity is controlled to be in a negative pressure environment, and the temperature is not higher than 500 DEG C; (2) transferring the low-density SiO2 loose body into a sintering furnace, and heating to 1100-1300 DEG C in a closed environment filled with dehydroxylation airflow and oxygen so as to dehydrate the low-density SiO2 loose body; (3) in an inert gas environment, introducing fluorine-containing gas into the sintering furnace, and heating to 1400-1600 DEG C, so that the low-density SiO2 loose body is vitrified to form transparent quartz glass; in the dehydration and vitrification process, the low-density SiO2 loose body is kept not moving in the longitudinal direction, and the longitudinal and radial temperature gradient in the deposition cavity is smaller than or equal to 2 DEG C; and (4) annealing the transparent quartz glass to obtain the synthetic quartz material. According to the method disclosed by the invention, the continuity of the production process is high, and T170-193nm of the synthesized quartz product is greater than or equal to 95%.

Description

technical field [0001] The invention relates to the technical field of quartz preparation, in particular to a method for producing a synthetic quartz material for a semiconductor mask. Background technique [0002] Quartz glass is a special glass composed of a single component of silica, and its chemical formula is SiO 2 . Quartz has unique optical, mechanical and thermal properties, including: high softening temperature, strong heat resistance; high purity, corrosion resistance; low thermal expansion coefficient, thermal shock resistance; good light transmittance from the ultraviolet band to the infrared band ; Strong radiation resistance; excellent electrical insulation, etc. The above properties make quartz products widely used in aerospace, laser optics, semiconductors, optical communications, metallurgy, chemical and other high-end manufacturing fields. [0003] Traditional optical quartz glass preparation processes include electrofusion, gas refining, chemical vapor...

AI Technical Summary

Problems solved by technology

Since most of the materials inside the deposition chamber are made of metal materials, metal chloride gas is easily generated under high temperature conditions and highly corrosive environments. The metal chloride gas flows with the airflow in the deposition chamber and deposits on the quartz material. materials causing pollution

The corrosion of the chamber during the pyrohydrolysis reaction makes the contamination of the quartz material with metal impurities inevitable, making it more difficult to reduce the content of metal impurities in the quartz material

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