What is the development path of sapphire substrate technology for LED?
The quality of the mainstream ultra-high-brightness LEDs currently on the market depends on the quality of the gallium nitride crystal layer, and the quality of the gallium nitride crystal layer is closely related to the quality of patterned sapphire substrates used. This is also the reason researchers focus on R & D and patent portfolio in the field of the sapphire substrate.
Because sapphire has excellent characteristics, its substrate can be used repeatedly as the main body of the substrate, so it can be used as a sacrificial substrate for LEDs. As a sacrificial substrate, related patent applications mainly involve the improvement of the structure and material of the separation layer. Forming a separation layer and a semiconductor film on a patterned sapphire substrate to form a semiconductor device can reduce the process difficulty and cost. At present, the C-plane sapphire substrate is a relatively mature and commonly used substrate in this field, with low manufacturing cost and stable physical and chemical properties.
Subsequently, the layout of patents in this field turned to the treatment of the surface of the patterned sapphire substrates. The formation of rough patterns on the substrate can improve the quality of the gallium nitride layer, thereby improving the luminous efficiency of the device.
In addition, in order to provide better raw sapphire crystal materials, scientists also focus on the research and development of raw material processing and cutting processes. For example, by improving processing technology to manufacture larger-sized patterned sapphire substrates, using diamond wire technology for cutting, etc., to facilitate large-scale manufacturing and production of sapphire substrates.
