Silicon Carbide Substrate Bonding for Reusable Carrier Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The manufacturing process of silicon carbide semiconductor components is expensive due to the significant removal of monocrystalline silicon carbide substrates during thickness reduction.
Innovation Solution
A method involving the deposition of silicon and germanium layers on polycrystalline and monocrystalline silicon carbide substrates using physical vapor deposition, followed by laser-induced connection and processing to create active regions, with a glass substrate adhesion and subsequent removal of the connection layer, allowing for cost-effective reuse of the polycrystalline substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the substrate thickness is reduced by grinding processes to achieve target thickness below 200 μm, then the required substrate thickness is achieved, but a large portion of the monocrystalline silicon carbide substrate is removed leading to high manufacturing costs
Solution Approach 1:
The substrate system is segmented into two distinct substrates: a monocrystalline silicon carbide substrate (50-100 μm thick) for active regions and a polycrystalline silicon carbide substrate as a reusable carrier. This segmentation allows the thin monocrystalline substrate to be processed without excessive material removal while the polycrystalline substrate serves as a durable platform that can be reused multiple times.
Solution Approach 2:
Silicon and germanium layers are deposited as intermediary connection layers between the monocrystalline and polycrystalline substrates. These intermediary layers facilitate bonding at moderate temperatures and can be selectively removed later, enabling the monocrystalline substrate to be released and the polycrystalline substrate to be reused for further manufacturing.
2Manufacturing precision
If laser beams are coupled in through the polycrystalline silicon carbide substrate to connect silicon and germanium layers, then precise connection is achieved, but the process complexity increases
Solution Approach 1:
The laser wavelength is specifically selected to exploit the differential optical absorption properties of silicon carbide polymorphs. The polycrystalline substrate is transparent to the chosen wavelength while the amorphous silicon and germanium layers absorb the laser energy, enabling selective heating and bonding. This parameter change allows precise control of the connection process without requiring complex additional equipment.
3Reliability
If high temperature processes are performed to create active regions, then the semiconductor component quality is improved, but the energy consumption and process complexity increase
Solution Approach 1:
Conventional thermal processing equipment (furnaces, heating chambers) is replaced with direct laser heating. The laser delivers concentrated energy precisely where needed, creating active regions through localized high-temperature processes. This substitution reduces overall energy consumption by eliminating the need to heat large chambers and allows for faster, more efficient processing with direct energy delivery to the substrate.
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 method reduces manufacturing costs and enables the reuse of polycrystalline substrates, maintaining the quality of the connection layer and adjusting its properties precisely, while keeping the process energy and temperature moderate.
Implementation Method 1
connecting the silicon layer and the germanium layer by means of a first laser, wherein laser beams are coupled in through the polycrystalline silicon carbide substrate
Implementation Method 2
high temperature processes are performed by means of a second laser having a wavelength of approximately 350 nm and an energy density of 0.5 J/cm2 to 5 J/cm2
Implementation Method 3
removing the connection layer by means of a third laser, wherein the laser beams are coupled in through the polycrystalline silicon carbide substrate
Implementation Method 4
depositing a silicon layer onto the polycrystalline silicon carbide substrate by means of physical vapor deposition and depositing a germanium layer onto the monocrystalline silicon carbide substrate by means of physical vapor deposition
Data Source
AI summary
A method for manufacturing a silicon carbide semiconductor component including a monocrystalline silicon carbide substrate and a polycrystalline silicon carbide substrate. The method includes: depositing a silicon layer onto the polycrystalline silicon carbide substrate; depositing a germanium layer onto the monocrystalline silicon carbide substrate; connecting the silicon layer and the germanium layer by a first laser, laser beams being coupled in through the polycrystalline silicon carbide substrate, and a connection layer consisting of silicon and germanium being produced; creating active regions on or within the monocrystalline silicon carbide substrate; depositing a glass substrate onto the active regions, the glass substrate being connected to the active regions by means of an adhesion layer; and removing the connection layer using a third laser, laser beams being coupled in through the polycrystalline silicon carbide substrate.