Flexible Freestanding Epitaxial Elements for Low-Stress Semiconductor Growth
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for forming flexible semiconductor devices face challenges such as high stress due to thermal expansion mismatch, limited availability of low-cost high-quality nitride and zinc oxide substrates, and the need for expensive and defect-prone processes like slicing and polishing, which compromise device performance and increase costs.
Innovation Solution
The development of flexible semiconductor devices grown on freestanding thin flexible epitaxial elements with a virgin as-grown surface, allowing for direct epitaxial growth without surface preparation, which reduces stress and eliminates polishing and miscut angle defects, and uses direct actinic heating for rapid and uniform temperature control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If flexible semiconductor devices are formed by removing epitaxial layers from rigid growth substrates via liftoff, then flexibility is achieved, but epitaxial stresses increase and device performance is compromised
Solution Approach 1:
The patent employs flexible freestanding epitaxial elements as thin film structures that inherently provide flexibility while maintaining low stress states. These elements are grown directly on flexible substrates and then released to form standalone flexible semiconductor devices, eliminating the need for rigid growth substrates and subsequent liftoff processes.
Solution Approach 2:
The invention extracts the epitaxial layers from rigid growth substrates through a controlled release process, creating freestanding flexible elements. This extraction is performed in a way that preserves the low-stress state of the epitaxial layers, allowing them to maintain their intrinsic flexibility and performance characteristics without the constraints of rigid substrate attachment.
2Ease of manufacture
If conventional wafer-based lithography and patterning equipment are used, then standard processing is enabled, but flexibility is lost due to rigid wafer requirements
Solution Approach 1:
The patent implements a dynamic processing approach where flexible epitaxial elements are grown on rigid substrates using standard equipment, then released and transferred to flexible configurations. This dynamic transition allows the system to leverage standard wafer-based processing capabilities while achieving final flexible device structures, bridging the gap between conventional manufacturing and flexible electronics.
3Manufacturing precision
If nitrides and zinc oxides are grown on native substrates at high temperatures, then high crystal quality is achieved, but costs increase due to narrow growth conditions
Solution Approach 1:
The patent employs flexible freestanding epitaxial elements that can serve multiple functions: they provide high-quality crystal growth surfaces, enable low-stress device fabrication, and offer flexibility for various device configurations. This multi-functionality allows a single platform to address multiple requirements, reducing the need for specialized expensive substrates and processes.
4Adaptability or versatility
If growth substrates are removed via liftoff, then flexibility is achieved, but surface defects and stress increase compromise device performance
Solution Approach 1:
The patent performs preliminary actions by growing the epitaxial layers directly on flexible substrates from the beginning, rather than on rigid substrates and then transferring them. This preliminary configuration ensures that the layers are grown in a low-stress state with clean surfaces, and the flexibility is inherent to the growth process itself, eliminating the need for damaging liftoff operations.
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 high-quality, cost-effective semiconductor device growth with reduced thermal stress, faster processing times, and improved device performance by minimizing surface defects and thermal mass, while allowing for dual-sided processing and high-temperature packaging.
Implementation Method 1
The epitaxial element is directly heated by actinic radiation wherein the epitaxial element absorbs at least a portion of the actinic radiation and is heated to a temperature within a reactor such that deposition, growth, curing, epitaxial growth, or formation of additional semiconductor device layer occurs
Data Source
AI summary
Flexible semiconductor devices based on flexible freestanding epitaxial elements are disclosed. The flexible freestanding epitaxial elements provide a virgin as grown epitaxy ready surface for additional growth layers. These flexible semiconductor devices have reduced stress due to the ability to flex with a radius of curvature less than 100 meters. Low radius of curvature flexing enables higher quality epitaxial growth and enables 3D device structures. Uniformity of layer formation is maintained by direct absorption of actinic radiation by the flexible freestanding epitaxial element within a reactor. In addition, standard post processing steps like lithography are enabled by the ability of the devices and elements to be flattened using a secondary support element or vacuum. Finished flexible semiconductor devices can be flexed to a radius of curvature of less than 100 meters. Nitrides, Zinc Oxides, and their alloys are preferred materials for the flexible freestanding epitaxial elements.