Integrated Bidirectional Switch with Shared Electrodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bidirectional AC switches, such as TRIACs and devices with IGBTs and diodes, are complex, costly, and have high turn-on resistance and voltage, with difficulties in stabilizing the reference potential for gating.
Innovation Solution
A bidirectional switching device with a main semiconductor region, including two main electrodes and a gate electrode, where the diodes are integrated with the semiconductor switch, sharing electrodes to reduce complexity and size, and the substrate potential is stabilized by connecting the back electrode to the diode-forming electrodes, ensuring reliable gating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If separate IGBTs and diodes are used in bidirectional switching device, then the device can achieve bidirectional switching function, but the construction becomes complex and size increases
Solution Approach 1:
The patent merges the IGBT and diode functions into a single integrated structure where the same semiconductor device provides both the switching transistor and the flywheel diode functionality through shared electrodes and integrated doping regions, eliminating the need for separate discrete components
Solution Approach 2:
The integrated switching device serves multiple functions simultaneously - it acts as both the main switching element and the flywheel diode for bidirectional current flow, with the same physical structure providing both switching and freewheeling capabilities
2Ease of operation
If separate IGBTs and diodes are used in bidirectional switching device, then the switching function is achieved, but the device size and manufacturing cost increase
Solution Approach 1:
The patent combines multiple discrete semiconductor components (IGBT and diode) into a single integrated device structure, reducing the overall device volume by eliminating separate packages, mounting areas, and interconnection spaces
Solution Approach 2:
The diode structure is nested within the same semiconductor substrate as the IGBT, with shared electrodes and overlapping functional regions, allowing one component to be effectively embedded within the other's physical footprint
3Ease of manufacture
If conventional semiconductor materials are used, then manufacturing is easier, but antivoltage strength is insufficient
Solution Approach 1:
The patent employs advanced semiconductor materials with higher breakdown voltage characteristics than conventional silicon, such as silicon carbide or other wide-bandgap materials, which provide superior antivoltage strength while maintaining compatibility with standard semiconductor fabrication processes
4Reliability
If self-contained components are used, then the device can function independently, but the construction becomes bulky and costly
Solution Approach 1:
The patent integrates multiple previously separate components into a single monolithic structure where the IGBT and diode share common electrodes and semiconductor regions, reducing the number of discrete parts while maintaining full functional capability
Solution Approach 2:
The integrated device structure provides multiple functions (switching, flywheel, bidirectional current flow) through a single component that serves universal purposes, eliminating the need for multiple specialized components
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 solution results in a simpler, smaller, and cheaper bidirectional switching device with reduced parasitic impedance, enabling high-speed operation and stable substrate potential, thus improving antivoltage strength and reliability.
Implementation Method 1
The gate electrode is positioned between the main electrodes for controlling current flow therebetween
Implementation Method 2
The two main electrodes and gate electrode provide in combination with the main semiconductor region a semiconductor switch
Implementation Method 3
The two main electrodes and two diode-forming electrodes constitute two diodes in combination with the main semiconductor region
Data Source
AI summary
A main semiconductor region grown on a substrate has formed on its surface a pair of main electrodes spaced from each other, a gate electrode between the main electrodes, and a pair of diode-forming electrodes spaced farther away from the gate electrode than are the main electrodes. Making ohmic contact with the main semiconductor region, the pair of main electrodes serve both as drain or source of a HEMT switch and as cathodes of a pair of Schottky diodes integrated with the HEMT switch. Both gate electrode and diode-forming electrodes are in Schottky contact with the main semiconductor region.