Semiconductor Device Asymmetric Insulating Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor devices, such as IGBTs, face challenges in reducing switching and conducting losses while improving electrical characteristics and safe operation area, particularly in achieving balanced on-resistance and breakdown voltage.
Innovation Solution
The semiconductor device incorporates a transistor cell with a drift region, a body region, active and body trenches, and asymmetric insulating layers, along with conductive layers, to enhance conductivity modulation and control gate feedback, thereby optimizing current and voltage gradients.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional trench structures with symmetric insulating layers are used, then manufacturing is simpler, but switching losses and conducting losses increase while electrical characteristics deteriorate
Solution Approach 1:
The patent applies asymmetry by configuring the insulating layer in the body trench with different thicknesses on opposite sides (first thickness on first sidewall, second thickness on second sidewall). This asymmetric structure creates non-uniform electric field distribution that optimizes both switching and conducting losses while maintaining manageable manufacturing complexity through a systematic design approach.
Solution Approach 2:
The patent implements local quality by providing different insulating layer thicknesses at different locations within the body trench. The first insulating layer portion has a first thickness while the second insulating layer portion has a second thickness, allowing localized optimization of electrical characteristics in different regions of the trench structure.
2Reliability
If symmetric insulating layers are used in body trenches, then manufacturing precision requirements are lower, but electrical characteristics and breakdown voltage performance worsen
Solution Approach 1:
The patent deliberately introduces asymmetry in the insulating layer configuration where the first thickness differs from the second thickness. This asymmetric design improves electrical characteristics and breakdown voltage by creating optimized electric field distribution, while the manufacturing precision challenge is addressed through defined thickness relationships (first thickness is greater than or equal to second thickness).
3Productivity
If conventional transistor structures are used, then device complexity is lower, but switching performance and safe operation area deteriorate
Solution Approach 1:
The patent applies segmentation by dividing the transistor cell into distinct functional regions: active trench with gate conductive layer, body trench with asymmetric insulating layers, and properly configured source regions. This segmented structure improves switching performance by creating well-defined electric field regions and charge distribution zones, while maintaining reasonable device complexity through systematic arrangement.
Solution Approach 2:
The patent implements feedback mechanisms through the body trench structure with asymmetric insulating layers that influence charge distribution and electric field formation. The conductive layers in both active and body trenches create feedback paths that optimize switching behavior and enhance safe operation area by controlling voltage and current gradients during switching transitions.
Data Source
AI summary
A semiconductor device is described in which a conductive channel is present along an active gate trench of the device when a gate potential is at an on-voltage, whereas no conductive channel is present along an inactive trench of the device for the same gate potential condition.