Generally, the epitaxial layers of GaN based materials and devices are mainly grown on sapphire substrates. Sapphire substrate has many advantages: firstly, the production technology of sapphire substrate is mature and the device quality is good; secondly, the stability of sapphire is very good, which can be used in the high temperature growth process; finally, the mechanical strength of sapphire is high, and it is easy to handle and clean. Therefore, sapphire is usually used as substrate material in most processes.
In display and electronic devices, the thickness of sapphire substrate is only hundreds of microns. In the process of sapphire substrate cutting, double-sided grinding, and single-sided grinding and polishing, although part of the processing stress will be released in the next process, the stress release is disorderly, and the unreleased processing stress will gather on the wafer surface and affect the warpage of sapphire wafer Serious warping will produce fragments in the subsequent processing, which will affect the wafer quality of the whole processing cycle.
In the process of sapphire substrate wafer processing, annealing treatment is required after grinding operation, and the substrate needs to be cleaned before annealing. The cleaned substrate is put into the annealing furnace for high-temperature annealing to remove the residual stress in the processing process and eliminate the deformation of the substrate caused by the residual stress.
Haoyue Technology focuses on the research and development of oxygen and oxygen free substrate annealing furnace equipment to meet the requirements of customer processing technology and create the ultimate industrial products.
Oxygen free annealing furnace for sapphire wafer
Oxygen annealing furnace for sapphire wafer
1. Stress relief: make sapphire easy to process and chip.
2. It can eliminate stress concentration, avoid wafer cracking automatically, and crack and crack in processing.
3. The larger the diameter, the longer the holding time; the cooling time should be longer than the heating time, so as to avoid stress again.
4. The larger the diameter, the longer the holding time; the cooling time should be longer than the heating time, so as to avoid stress again.
1）Oxygen free annealing furnace
2）Oxygen annealing furnace
sapphire wafer annealing