| 摘要 |
PURPOSE:To relieve stress concentration and prevent defect when the thick film is formed, by exercising oxidation with thick SiO2 film formed at the end of Si3N4 film which works as a mask for selective oxidation. CONSTITUTION:During oxidation of an Si substrate, SiO2 thick film is formed in proportion to 1/2 power of the oxidation time, and the speed of forming oxidation film slows down as the film gets thicker. Therefore, by oxidating on Si substrate 11 with SiO2 thick film formed at the end of Si3N4 film 14 which works as a mask for selective oxidation, stress concentration can be decreased and defect eliminated, although SiO2 film 15 formed will be thinner. Thus, leak current and noise is decreased. |
