Preparation method of avalanche photodiode diffusion structure and diode diffusion structure

Abstract

The invention provides a preparation method of an avalanche photodiode diffusion structure and a diode diffusion structure. The method includes: on the epitaxial wafer of the avalanche photodiode, under the action of the first photolithography mask, perform the first dopant diffusion to obtain the central circular diffusion main junction region (1) and the diffusion main junction region (1). Diffusion tank regions (2) with a predetermined distance between the junction regions; under the action of the second photolithography mask, a second dopant diffusion is performed, so that the central region (101) or edge region of the diffusion main junction region The depth of (102) is greater than the depth of the diffused main junction region obtained through the first dopant diffusion, thereby obtaining an avalanche photodiode diffused structure. The uniformity of chip breakdown voltage is regulated while suppressing edge breakdown.

Description

technical field [0001] The invention relates to the field of photodetectors, in particular to a preparation method of an avalanche photodiode diffusion structure and a diode diffusion structure. Background technique [0002] Avalanche photodiodes of III-V semiconductor materials are widely used in near-infrared photodetection and other related fields, such as optical fiber communication systems, near-infrared detection fields, and quantum communication single-photon detection. An avalanche photodiode (Separate Absorption and Multiplication Avalanche Photodiode: SAM-APD) structure with a separate absorption and multiplication layer can provide an electrical signal output with high fidelity (ie, low noise). On this basis, an avalanche photodiode (Separate, Absorption, Grading, Charge and Multiplication Avalanche Photodiode: SAGCM-APD) with a separate charge control layer and transition layer is added, which optimizes the electric field distribution of the device and reduces th...

AI Technical Summary

Problems solved by technology

Although the breakdown voltage deviation in the array can be compensated according to the test structure, this test and compensation device is complex and expensive, and it is not universal, and in imaging sensors, position sensors, etc., the impact of breakdown voltage changes is destructive

The breakdown voltage deviation in this array increases the complexity and cost of the external circuit and also degrades the performance of the avalanche photodiode array to some extent.

Images