III-Nitride Stacked Structure Growth on Silicon With Dislocation Blocking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing III-nitride semiconductor devices face challenges in achieving high crystallinity and reducing material costs, particularly with silicon substrates, which lack heat dissipation and have high threading dislocation densities, affecting device reliability and performance.
Innovation Solution
A method involving the formation of protrusions on a silicon growth substrate, followed by the growth of buffer layers and the deposition of growth prevention films to inhibit threading dislocations, resulting in a non-emitting III-nitride semiconductor stacked structure with improved film quality and reduced dislocation density.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a silicon substrate is used to reduce material costs, then manufacturing cost is reduced, but threading dislocation density increases and crystallinity deteriorates
Solution Approach 1:
The buffer layer is segmented into multiple layers with different aluminum compositions (first buffer layer with 0≤x≤0.3, second buffer layer with 0.3<x≤1), allowing each layer to serve different functions in managing dislocations while maintaining overall crystallinity on silicon substrate
Solution Approach 2:
Growth prevention films are selectively formed only in specific regions (first and second regions) of the buffer layer, creating local variations in dislocation blocking while allowing other regions to maintain growth continuity, thus improving crystallinity locally without compromising overall structure
2Manufacturing precision
If a sapphire substrate is used to improve crystallinity, then manufacturing precision is improved, but heat dissipation capability deteriorates
Solution Approach 1:
A silicon substrate is introduced as an intermediary between the heat dissipation requirement and the III-nitride semiconductor layer, with specially designed buffer layers and growth prevention films that mediate between the silicon's poor crystalline match and the need for high crystallinity, enabling heat dissipation through silicon while maintaining crystallinity through the buffer structure
3Temperature
If a SiC substrate is used to improve heat dissipation, then temperature management is improved, but material cost increases
Solution Approach 1:
The invention uses a silicon substrate (cheaper than SiC) as a temporary growth platform, with the understanding that the substrate may need to be removed or replaced later, allowing cost-effective manufacturing while achieving the thermal management benefits typically associated with more expensive substrates
4Reliability
If growth prevention films are formed to block threading dislocations, then reliability is improved, but device complexity increases
Solution Approach 1:
The buffer layer is divided into multiple segments (first and second buffer layers with different compositions) with growth prevention films placed at specific interfaces, segmenting the dislocation blocking function across different regions and layers to reduce overall dislocation density while maintaining manageable structural complexity
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 enhances the crystallinity and reduces threading dislocation density to less than 10^7/cm², improving the reliability and performance of III-nitride semiconductor devices while utilizing cost-effective silicon substrates.
Implementation Method 1
the growth prevention film 150 enables epitaxially lateral overgrowth (ELOG) as in the III-nitride semiconductor stacked structure shown in FIG. 1 and also serves to block the defects 180 occurring below
Data Source
AI summary
The present disclosure relates to a method for manufacturing a non-emitting III-nitride semiconductor stacked structure, the method comprising the steps of: preparing a growth substrate containing silicon (Si); forming a plurality of protrusions on the growth substrate; growing a first buffer layer to cover the plurality of protrusions on the growth substrate; forming a plurality of growth prevention films on the first buffer layer, growing a second buffer layer from the first buffer layer exposed through the growth prevention films; and forming a non-emitting III-nitride semiconductor stacked structure on the second buffer layer.