Core key technologies of epitaxial materials

Innovatively propose high-quality defect and stress control technology for ultraviolet LED epitaxial materials, achieving a reduction in dislocation density of ultraviolet LED materials to 3 × 10 ⁸ cm ⁻ ², reaching the international advanced level

Dislocation density control

The dislocation density has been reduced to 3 × 10 ⁸ cm ⁻ ², reaching the international advanced level

Effective stress release

Innovative Pyramid Nanographic NPSS Substrate Epitaxial Growth and Healing Technology

Nobel laureates recognized

2014 Nobel Prize winner in Physics, Nakamura, highly praised

Innovative high-quality ultraviolet LED epitaxial material defect and stress control technology

Breakthrough improvement in epitaxial material quality achieved through graphical substrate, thickness control, dislocation merging, and stress relief techniques

Graphic substrate surface morphology

The graphical substrate surface observed by atomic force microscopy (AFM) presents a regular arrangement of pyramid shaped or conical structures, uniformly distributed, providing an ideal template for epitaxial growth

surface feature
Pyramid shaped microstructure array
Regular grid arrangement
3D surface morphology control

Thickness exceeding 10 µ m

Scanning electron microscopy (SEM) cross-sectional images show the growth of AlN layer on sapphire substrate, with a thickness exceeding 10 µ m, including vertically extending air holes

Material structure hierarchy
AlN layer Thickness>10 µ m
Air hole Vertical extension
Sapphire h = 6. 6µm

Bending annihilation during dislocation merging process

Transmission electron microscopy (TEM) images show the bending, merging, and annihilation processes of dislocation defects in the epitaxial layer during growth, effectively reducing defect density

Dislocation control mechanism
Dislocation bending
Dislocation merging
Dislocation annihilation

Effective stress release

Reverse space mapping (RSM) analysis displays the stress state and crystal quality in the material, achieving high-quality epitaxial growth through effective stress release techniques

Stress analysis parameters
Qx×10000 (rlu) 2810-2880
Qz×10000 (rlu) 7715-7750
Stress state Effective Release

Technological achievements and intellectual property rights

Innovative achievements based on epitaxial technology have been recognized by Nobel laureates and successfully applied to satellite exploration engineering

core patents

Ultra wide bandgap aluminum nitride epitaxial wafers and their preparation methods
Patent number: ZL201811380251.1
A heterogeneous epitaxial substrate for deep ultraviolet LED and its preparation method and application
Patent number: ZL202110397975.2

Representative paper

Applied Physics Letters
2019, 114. 4
Optics Express
2018, 26. 2: 680-686

Application achievements

Ocean One Satellite Exploration Project
Online monitoring of marine environment
Application of AlGaN material
Successfully applied to satellite systems

Evaluation of Nobel laureates

2014 Nobel Prize winner in Physics Nakamura

This technological innovation is expected to make low dislocation density AlN/NPSS a reality through novel growth methods and annealing techniques

Summary of Technical Advantages

Innovative Pyramid Nanographic NPSS Substrate Technology
Effective release of stress and promotion of error control
The dislocation density is reduced to 3 × 10 ⁸ cm ⁻ ²
Reaching the international advanced level
Successfully applied to satellite exploration engineering
Highly praised by Nobel laureates