Views: 26 Author: Site Editor Publish Time: 2021-05-17 Origin: Site
Patterned sapphire substrate (PSS), that is, a dry etching microstructure grown on a sapphire substrate.
The microstructure is patterned by a standard photolithography process, and the sapphire is etched using ICP etching technology. Then GaN epitaxy can be grown on it.
The vertical epitaxy of the GaN material is changed to the lateral epitaxy.
On the one hand, it can effectively reduce the dislocation density of the GaN epitaxial material, thereby reducing the non-radiative recombination of the active area,
reducing the reverse leakage current, and improving the life of the LED;
On the other hand, the light emitted from the active area is scattered multiple times by the interface between the GaN and the sapphire substrate, which changes the exit
angle of the total reflection light and increases the probability that the light of the flip-chip LED exits the sapphire substrate, thereby improving the light extraction efficiency.
Therefore, the output brightness of the LED grown on the PSS is greatly improved than that of the traditional LED, while the reverse leakage current is reduced, and the life
of the LED is also extended.
With the development of process technology in the LED field and the rapid growth of the entire LED industry, research on PSS substrates for GaN-based LED devices has gradually increased.
Nowadays, various manufacturers have adopted PSS technology to improve the light extraction efficiency of LED devices. There are many types of PSS patterns.
FineWin wafers can provide Patterned Specification Diameter: 2.7 ± 0.15 μm; Spacing: 0.3 ± 0.15 μm; Depth: 1.75 ± 0.15 μm. Pattern Type is 3 μm pitch, Cone Type.