Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To readily form epitaxial layers of different partial thicknesses with flat surfaces by forming a polygonal recess of a main body at the side parallel to the (100) direction on the (100) surface of a P type Si and covering the surface with an N type epitaxial layer. CONSTITUTION:A window having a side parallel to (100) is formed at an SiO2 52 on the (100) surface of a P type Si substrate 51, and is anisotropically etched, thereby forming a recess 501. After N+ type layers 53, 531 are diffused, an N type epitaxial layer 54 is superposed, and an SiO2 mask 55-551 are covered on the recess 502. It is again anisotropically etched to flatten the surface of the layer 54, and the remaining SiO2 mask 55 is removed. Thereafter, a high withstand voltage part 101 and a low withstand voltage part 102 are isolated via the P type layer 59, and a linear IC is formed in the ordinary way. According to this structure, an Si device having an epitaxial layer having partly different thickness and flat surface can be readily obtained by employing the mask of the side parallel to the prescribed direction as a main body and performing twice anisotropic etchings and once entire epitaxial growth.

Inventors

• 👤 Ichiro Imaizumi
• 👤 今泉　市郎
• 👤 Masatoshi Kimura
• 👤 正利 木村
• 👤 Keijiro Uehara
• 👤 敬二郎 上原

Bibliographic Details