Stepped Guard Ring Structure for Avalanche Photodiode Edge Breakdown
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional guard rings in planar avalanche photodiodes, particularly those using indium gallium arsenide grown on indium phosphide, suffer from edge breakdown due to high electric field concentration, leading to increased dark count rates and decreased breakdown gain, which is not adequately addressed by single attached guard rings.
Innovation Solution
A guard ring structure featuring multiple attached guard rings forming a stepped configuration, with each ring having a specific width and height relationship, is introduced to effectively disperse the electric field and suppress edge breakdown, replacing the need for floating guard rings and optimizing area utilization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single attached guard ring is used, then the structure is simple, but edge breakdown cannot be properly suppressed due to insufficient electric field dispersion
Solution Approach 1:
The single attached guard ring is segmented into multiple attached guard rings arranged in a stepped configuration. This segmentation allows each ring to contribute to electric field dispersion at different radial positions, thereby improving edge breakdown suppression while maintaining a relatively simple attached guard ring structure without requiring floating guard rings.
2Reliability
If floating guard rings are used instead of multiple attached guard rings, then electric field dispersion may be improved, but area utilization rate increases and manufacturing costs rise
Solution Approach 1:
Multiple attached guard rings are merged into a unified stepped structure that integrates the functions of electric field dispersion and area efficiency. The stepped configuration allows the guard rings to be closely spaced and radially arranged, maximizing area utilization while achieving effective electric field dispersion without requiring additional floating guard ring structures.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The stepped guard ring structure enhances detection efficiency and jitter performance while reducing manufacturing costs by improving electric field concentration and area efficiency, making it suitable for LIDAR devices and avalanche photodiodes.
Implementation Method 1
edge breakdown occurs at a Zn diffusion edge of, for example, a planar avalanche photodiode due to a high electric field concentration effect
Data Source
AI summary
A guard ring structure and a component structure are provided. The guard ring structure includes a first attached guard ring and a second attached guard ring. The first attached guard ring is disposed at a periphery of an active region. The second attached guard ring is disposed at a periphery of the first attached guard ring. The first attached guard ring and the second attached guard ring are each an attached guard ring, and form a stepped structure. The guard ring structure is a stepped diffusion structure for an avalanche photodiode.