Semiconductor device and manufacture thereof

Abstract

Abstract PURPOSE:To obtain a hetero-bipolar transistor capable of being operated at high speed by diffusing a P-type impurity as a graft base to a semi-insulating substrate and reducing a base-collector junction area. CONSTITUTION:An N-type InP layer 2, a P-type InGaAsP layer 3 and an N-type InP layer 4 are grown on a semi-insulating InP substrate l by using a liquid phase epitaxial growth method in succession. The N-type InP layer 4 and the P-type InGaAsP layer 3 are removed selectively by employing a normal photolithographic step and an etching step. A P-type impurity is diffused selectively through a normal insulating step, the photolithographic step and a diffusion process. The impurity is diffused in such a manner that it punches through the P-type InGaAsP layer 3 and the N-type InP layer 2 from the surface of the N-type InP layer 4 and reaches to the semi-insulating InP substrate I, and a P-type impurity diffusion layer 8 is shaped. The N-type InP layer 4 is removed selectively through the normal photolithographic step and the etching step.

Inventors

• 👤 Soichi Kimura
• 👤 木村　壮一

Bibliographic Details