Avalanche photodiode

Abstract

Abstract PURPOSE:To obtain a high guard-ring effect by a method wherein a portion of curvature of a larger P-N junction within a photodetection region which constitutes an avalanche photodiode is formed in a semiconductor with a large forbidden band width to increase a breakdown voltage. CONSTITUTION:An N type In1-xGaxAsyP1-y (0.42<=x<=0.5y, 0<=y<=1) layer 11 is grown on an N type InP substrate 10, and a P type In1-xGaxAsyP1-y layer 12 is formed within the layer 11 to create the P-N junction face 13, which becomes a photodetection region, on the interface formed by these layers 11 and 12 for making a diode. In this construction, a P type In1-pGapAsqP1-q (0.42q<=P<=0.50q, 0<=q<= 1) layer 14 having a larger forbidden band width than that of the layers 11 and 12 is diffusion-formed on the both ends 19 with a large radius of curvature, and in such a manner as surrounding this, an N type In1-pGapAsqP1-q layer 15 with a large forbidden band width is similarly diffusion-formed within the layer 11 to create a P-N junction 20 on the interface formed between the layers 14 and 15. Thus, the withstand voltage at the junction 20 is made larger than that of the junction 13.

Inventors

• 👤 Kazuo Sakai
• 👤 Yuichi Matsushima
• 👤 Shigeyuki Akiba
• 👤 Akiya Yamamoto

Bibliographic Details