Hetero-structure semiconductor device

Abstract

Abstract PURPOSE:To obtain a photodetector stable in operation by forming one conductivity type layer having a wide forbidden band width as compared with one conductivity type semiconductor substrate thereon, and forming a reverse conductivity type region formed thereon as a P-N junction of a concentrical region deep in a shallow cylindrical post region when forming the reverse conductivity type region. CONSTITUTION:N<+> type InP layer 12, N<-> type InGaAsP layer 13 and N<-> type InP layer 14 are laminated and epitaxially grown on an N<+> type InP substrate 11. Then, a circular mask 151 made of SiO2 or Si3N4 is formed on the peripheral edge of the surface of the uppermost layer 14, Cd or Zn is diffused in the layer 14, a shallow cylindrical post-shaped p guard ring region 21 is formed in the layer 14, and first P-N junction 22 is formed between the region 21 and the layer 14. Thereafter, the same impurity is diffused in the region 21, and a deeper concentrical avalanche amplification p type region 23 is formed than the region 21, and a second P-N junction 24 is formed between the region 23 and the layer 14. Thus, the region 23 is formed deeply, a depletion layer allows to reach the hetero boundary 18 at the time of breakdown as a high speed and high sensitivity photodiode.

Inventors

• 👤 Yoshinari Matsumoto
• 👤 Kenshin Taguchi

Bibliographic Details