Starved source diffusion for avalanche photodiode

US7553690B2 · kind B2 · utility

Assignee

• FINISAR CORPORATION · US

Inventors

• Daniel Francis · Los Altos, US
• Rashit Nabiev · Palo Alto, US
• Richard Ratowsky · Castro Valley, US
• David Bruce Young · Taipei, TW
• Sunil Thomas · Palm Harbor, US
• Roman Dimitrov · San Jose, US

Key dates

• Filing date: Jun 14, 2005
• Grant date: Jun 30, 2009
• Expiry date: Aug 12, 2025

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E10/50

Abstract

This disclosure is concerned with starved source diffusion methods for forming avalanche photodiodes are provided for controlling an edge effect. In one example, a method for manufacturing an avalanche photodiode includes forming an absorber layer and an avalanche layer over a substrate. Next, a patterned mask defining one or more openings is formed over a surface of the avalanche layer. Finally, a dopant is deposited over the patterned mask and the avalanche layer such that the dopant is blocked by the patterned mask but diffuses into the avalanche layer in areas where the patterned mask defines an opening. The patterned mask is configured such that the depth to which the dopant diffuses into the avalanche layer varies so as to form a sloped diffusion front in the avalanche layer.