Process for making doped SiO2 layers fuse in fabricating integrated MOS semiconductor circuits

摘要

In order to level out topographic unevennesses prior to metallisation, the doped SiO2 (4) applied as an insulating interlayer to the substrate (3) provided with polysilicon structures (1) is made to fuse in a gas atmosphere which consists of oxygen and/or nitrogen and has a humidity of between 10 and 30 % by volume of water, at a temperature of less than 1000 DEG C. Owing to the low humidity, the surface oxidation of the substrate (3) is reduced; the fusing ratio is optimal and as good as in the known processes. The process is used in the fabrication of integrated MOS semiconductor circuits by VLSI techniques. <IMAGE>