Power Semiconductor Termination Ring Trenches Breakdown Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power semiconductor devices face challenges in maintaining high breakdown voltage due to edge and corner junction curvature, leading to reduced breakdown voltage and increased production costs from complex termination structures like deep-ring-trench termination, which occupy a large area and affect device performance.
Innovation Solution
A power semiconductor device with a termination structure featuring ring trenches and semiconductor plugs formed in the substrate, reducing the need for extra doping regions and simplifying the fabrication process, while enhancing breakdown voltage by distributing the electric field effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If deep-ring-trench termination structures are used to maintain breakdown voltage, then breakdown voltage is improved, but device area increases and manufacturing complexity increases
Solution Approach 1:
The termination structure is segmented into multiple discrete ring trenches arranged in a pattern around the active device area, rather than using a continuous deep trench. This segmentation reduces the total area occupied while maintaining the electric field distribution benefits needed for high breakdown voltage.
Solution Approach 2:
The solution transitions from a three-dimensional deep-ring-trench structure to a primarily two-dimensional array of shallower ring trenches. By reducing depth and increasing lateral distribution, the structure achieves similar electrical performance with reduced area occupation and manufacturing complexity.
2Reliability
If deep-ring-trench termination structures are used to maintain breakdown voltage, then breakdown voltage is improved, but manufacturing complexity and cost increase
Solution Approach 1:
The termination structure is divided into multiple discrete ring trenches that can be formed using standard photolithography and etching processes, avoiding the need for complex deep-trench formation techniques. This segmentation enables manufacturing using conventional semiconductor fabrication processes.
Solution Approach 2:
By reducing the trench depth and emphasizing lateral arrangement, the structure becomes compatible with standard shallow-trench isolation processes already used in semiconductor manufacturing, thereby reducing manufacturing complexity and cost while maintaining electrical performance.
3Reliability
If termination structures occupy large area to ensure breakdown voltage, then breakdown voltage is improved, but device size increases
Solution Approach 1:
The termination structure uses multiple discrete ring trenches positioned strategically around the active device, creating an efficient perimeter-based configuration. This segmented approach provides adequate termination function with minimal encroachment on the active device area, thereby reducing overall device size.
Solution Approach 2:
The solution emphasizes two-dimensional lateral arrangement of shallow trenches over three-dimensional deep structures, achieving effective voltage termination with reduced area occupation and smaller overall device footprint.
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 proposed solution significantly increases the breakdown voltage of power semiconductor devices, reduces production costs, and minimizes the device size by optimizing the number and depth of ring trenches, thereby improving voltage endurance and preventing current leakage.
Implementation Method 1
enhancing breakdown voltage by distributing the electric field effectively
Data Source
AI summary
A method for forming power semiconductor device is provided. The power semiconductor device includes a substrate having a device region and a surrounding termination region; and at least a power device formed in the device region of the substrate. The power semiconductor substrate also includes a termination structure having a plurality of semiconductor plugs formed in a first surface of the termination region of the substrate. Wherein the plurality of the semiconductor plugs are formed in a plurality of ring trenches formed in the first surface of the substrate in the termination regions, with a semiconductor plug formed in each of the plurality of ring trenches.