Stacked III-V Diode Metamorphic Buffer for Low Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing high-voltage III-V power semiconductor diodes face challenges in achieving low series resistance, low forward voltage, and minimal reverse leakage current while maintaining high breakdown voltages above 200V.
Innovation Solution
A stacked high barrier III-V power semiconductor diode design featuring a heavily doped semiconductor contact region, a drift layer, and a metamorphic buffer layer sequence with varying lattice constants, allowing for the use of III-V compounds with lower bandgaps and improved mobility, and integration of metallic terminal contact layers for reduced series resistance and enhanced electrical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a high breakdown voltage is achieved through conventional diode design, then the breakdown voltage exceeds 200V, but the series resistance and forward voltage remain high, causing power loss
Solution Approach 1:
The patent changes the material composition parameters by using III-V compound semiconductors (such as GaAs, InGaAs) instead of conventional silicon, and heavily dopes the contact regions with dopant concentrations greater than 1×10^18 N/cm³. This parameter change enables simultaneously achieving high breakdown voltage (>200V) and low forward voltage drop, reducing power loss while maintaining voltage blocking capability
Solution Approach 2:
The patent employs composite material structures including metamorphic buffer layer sequences with varying composition gradients, III-V compound semiconductor layers with different bandgaps, and stacked heterostructure designs. These composite structures enable optimization of both breakdown voltage and forward voltage characteristics, resolving the contradiction between high voltage blocking and low power loss
2Strength
If conventional semiconductor materials are used to achieve high breakdown voltage, then voltage blocking is improved, but reverse leakage current exceeds 1 microampere
Solution Approach 1:
The patent applies local quality optimization by creating heavily doped contact regions with dopant concentrations >1×10^18 N/cm³ at specific locations, while maintaining lower doping in the drift region. This localized doping strategy, combined with III-V compound materials, achieves high breakdown voltage while suppressing reverse leakage current to below 1 microampere through improved junction characteristics
Solution Approach 2:
The patent changes material parameters by using III-V compound semiconductors with appropriate bandgap energies and heavy doping concentrations, which fundamentally alters the reverse leakage characteristics compared to conventional materials, enabling simultaneous achievement of high breakdown voltage and ultra-low reverse leakage current
3Speed
If III-V compounds with lower bandgaps are used to improve mobility and reduce forward voltage, then transient electrical properties improve, but lattice mismatch issues arise
Solution Approach 1:
The patent introduces metamorphic buffer layer sequences as intermediary structures between substrates and active III-V layers. These buffer layers with graded composition profiles serve as transition zones that accommodate lattice mismatch, enabling the use of low-bandgap III-V compounds (such as InGaAs) with high electron mobility while preventing defect propagation to the active devices
Solution Approach 2:
The patent systematically changes composition parameters across the buffer layer sequence, creating graded structures where indium content increases progressively. This parameter gradient approach transforms the abrupt lattice mismatch into a gradual transition, enabling high-mobility III-V materials to be used without compromising device quality
Data Source
AI summary
A stacked high barrier III-V power semiconductor diode having an at least regionally formed first metallic terminal contact layer and a heavily doped semiconductor contact region of a first conductivity type with a first lattice constant, a drift layer of a second conductivity type, a heavily doped metamorphic buffer layer sequence of the second conductivity type is formed. The metamorphic buffer layer sequence has an upper side with the first lattice constant and a lower side with a second lattice constant. The first lattice constant is greater than the second lattice constant. The upper side of the metamorphic buffer layer sequence is arranged in the direction of the drift layer. A second metallic terminal contact layer is arranged below the lower side of the metamorphic buffer layer sequence. The second metallic terminal contact layer is integrally bonded with a semiconductor contact layer.