Multi-Trench Termination Structure for Schottky Diodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Schottky diodes have low reverse voltage tolerance and high reverse leakage current due to stress from trench-etching, leading to potential device malfunction and damage during reliability tests.
Innovation Solution
A multi-trench termination structure is created by forming a semiconductor substrate with a mask layer, etching trenches, applying a gate insulation layer, and depositing an electrically conductive and metal layer to enhance reverse voltage tolerance, while avoiding stress-related issues through surface smoothing and ion implantation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If a trench structure is formed to pinch off reverse leakage current, then reverse leakage current is reduced, but stress from trench-etching causes device damage and malfunction
Solution Approach 1:
The invention divides the single trench structure into multiple segmented trenches arranged in a specific pattern. This segmentation allows the stress from etching to be distributed across multiple smaller trenches rather than concentrated in one large trench, reducing the overall stress impact while maintaining the current pinching effect. The segmented trenches are filled with dielectric material and metallization layers to create a multi-trench termination structure that effectively manages both leakage current and stress.
Solution Approach 2:
The invention applies different properties to different regions of the trench structure. The trenches are selectively formed in the termination region rather than uniformly across the entire device. The dielectric filling and metallization layers are applied locally in specific patterns within the trenches, creating regions with different electrical and mechanical properties. This local differentiation allows current pinching where needed while managing stress in other regions.
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 method significantly increases the reverse voltage tolerance of Schottky diodes by effectively spreading the electric field and reducing current leakage, thereby improving device reliability and performance.
Implementation Method 1
forming a gate insulation layer on the multi-trench structure
Implementation Method 2
depositing an electrically conductive and metal layer
Implementation Method 3
avoiding stress-related issues through surface smoothing and ion implantation
Data Source
AI summary
A multi-trench termination structure for semiconductor device is disclosed, where the semiconductor device includes a semiconductor substrate and an active structure region. The multi-trench termination structure includes multiple trenches defined on an exposed face of the semiconductor substrate, a first mask layer formed on a partial exposed surface of the semiconductor substrate and corresponding to a termination structure region of the semiconductor device, a gate insulation layer formed in the trenches, a conductive layer formed on the gate insulation layer and protruding out of the exposed surface of the semiconductor substrate, and a metal layer formed over the first mask layer and conductive layer on the termination structure region of the semiconductor device.