SiC Epitaxial Layer Bonding via Room-Temperature Diffusion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge lies in achieving a semiconductor substrate structure with stable bonding strength and high reliability, particularly under high temperature environments, while also reducing material restrictions and costs, and improving the physical properties of power semiconductor devices. This is complicated by the difficulty in obtaining a flat surface for porous support substrates, leading to insufficient bonding strength and challenges in using materials that do not readily form a stable liquid phase.
Innovation Solution
The proposed solution involves a semiconductor substrate structure where a silicon carbide epitaxial growth layer is bonded to a substrate using room-temperature bonding or diffusion bonding techniques, with a surface roughness improvement layer to enhance bonding strength and reliability. This allows for the use of arbitrary substrates and SiC epitaxial growth layers, expanding material combinations and reducing manufacturing costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional high-temperature bonding methods are used, then bonding strength can be achieved, but material restrictions increase and manufacturing costs rise
Solution Approach 1:
The patent changes the bonding temperature parameter from conventional high temperature to room temperature, enabling bonding of materials that would otherwise be restricted by thermal compatibility requirements. This parameter change allows arbitrary substrate and SiC epitaxial growth layer combinations without material restrictions.
Solution Approach 2:
The patent replaces thermal bonding mechanisms with room-temperature bonding mechanisms, substituting the need for high-temperature thermal fields with alternative bonding methods that operate at ambient conditions, thereby expanding material compatibility.
2Ease of manufacture
If porous support substrates are used to reduce costs, then manufacturing costs decrease, but bonding reliability deteriorates due to surface flatness issues
Solution Approach 1:
The patent applies preliminary surface treatment to the porous support substrate to improve surface flatness before bonding. This preliminary action compensates for the inherent surface irregularities of porous substrates, enabling reliable bonding while maintaining cost advantages.
3Adaptability or versatility
If room-temperature bonding is used, then material restrictions are eliminated and costs are reduced, but bonding stability under high temperature may be compromised
Solution Approach 1:
The patent introduces a bonding agent as an intermediary substance between the substrate and SiC epitaxial growth layer. This bonding agent forms a stable interface that maintains bonding integrity under high-temperature operating conditions, even though the bonding process itself occurs at room temperature.
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
This approach enables stable bonding even at high temperatures, expands material combinations, reduces manufacturing costs, and improves the thermal, electrical, and mechanical properties of power semiconductor devices, leading to enhanced switching characteristics and reliability.
Implementation Method 1
the substrate and the silicon carbide epitaxial growth layer are bonded by a diffusion bonding
Data Source
AI summary
A semiconductor substrate structure includes: a substrate; and an epitaxial growth layer bonded to the substrate, wherein the substrate and the epitaxial growth layer are bonded by a room-temperature bonding or a diffusion bonding.