Silicone gels for semiconductor

Silicone gels intended for direct application to active semiconductor devices, especially VLSI s, are controlled for sodium, potassium and chloride content. Values range from one to two parts per million each, to as little as 0.1 part per million. Test methods can have an impact on the value quoted. 

Even though silicon is extremely abundant, only one silicon-containing compound appears in the list of top 50 industrial chemicals. That is sodium silicate, Na2 Si03, used for the manufacture of silica gel and glass. Nevertheless, with the advent of the electronic age silicon has become an extremely important substance that is the primary ingredient of most semiconductors. Because these are microscale devices, the quantity of production of silicon remains small compared with that of fertilizers and construction materials. Although relatively small in quantity, the value of silicon products is quite high. 

This process has been used in the early 1960s to fabricate pure ultrafine pSiC powders especially suited for the semiconductor and pigment industry [37,38]. During the first step of the General Electric Process [37] a silica gel is formed by hydrolysis of silicon tetrachloride in an aqueous solution of sugar (sucrose). Upon dehydratization at 300°C the sugar pyrolizes and an intimate amorphous carbon/amorphous silica mixture is obtained which is subsequently fired at 1800°C in an inert atmosphere to form pSiC. 

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