Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To increase remarkedly the surface area of a capacitor plate and to obtain a sufficient capacity even in a fine area by a method wherein a roughness is provided on the capacitor plate itself. CONSTITUTION:A first oxide film 7, a first poly-Si film 8, a second oxide film 9 and a second poly-Si film 10 are each deposited on a MOS transistor formed on an Si substrate by a known method in a desired thickness by a CVD method. The poly-Si film 10 is etched by anisotropic etching and is made to remain only on the sidewall part of the film 9. Then, after the film 9 only is selectively removed by etching of a high selection ratio to polysilicon, a capacitor oxide film is deposited by a CVD method or a thermal oxidation method. Then, a third poly-Si film 12 is deposited in a desired thickness by a CVD method and is patterned by a photolithographic method to form a capacitor. Thereby, a capacity of 4 times or thereabouts compared to the conventional capacitor of the same area as that of the capacitor can be obtained.

Inventors

• 👤 Nobuo Aoi
• 👤 Yoshitaka Dansui
• 👤 Masabumi Kubota

Bibliographic Details