Patent · US Expired

Semiconductor integrated circuit with photo diode

US5252851A · kind A · utility

37Cited by
2References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 28, 1992
Grant dateOct 12, 1993
Priority date
Expiry dateJan 28, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10F39/103

Abstract

An optical semiconductor is integrated with a transistor by epitaxially growing a lightly doped epitaxial layer on a substrate. One isolated island area of the epitaxial layer contains a diffusion area on its surface to form the optical semiconductor. A second isolated island area has its conductivity type inverted by a buried layer that is diffused upward into contact with a surface layer that is diffused downward. The upward-diffused and downward-diffused layers unite to form a collector of the transistor. A base area in the surface of the collector contains an emitter in its surface. The emitter and the diffusion area are formed of the same material, and in the same process steps.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.