Semiconductor Advanced Technology
New Process
[One-step transfer] The process adopts a new crucible design of a porous graphite cylinder. The SiC material particles were placed between the crucible wall and the porous graphite cylinder. The whole crucible is deeper and bigger compared with the regular crucible. So we can put more materials and the evaporation area is bigger. This process solves the problem of crystal defects caused by the recrystallization of materials. The new process reduces the sensitivity of the temperature distribution in the material area to crystal growth, improves and stabilizes the transfer efficiency, and reduces the impact of carbon inclusions in the late growth period. [One-step transfer] without sticking seed crystal can be used to free thermal expansion, which is conducive to stress release. [One-step transfer] The process optimizes the hot zone and improves the efficiency of expanding.
*new process means [One-step transfer]
Axial and Radial Temp Control Separate
[Axial and Radial Separation] is adopted by graphite furnace to solve the temperature coupling phenomenon of induction furnace. Adjust the axial temperature gradient to increase the crystal growth rate, but the radial temperature gradient will also be changed, which will lead to the change of the crystal growth surface, to increase of stress and crystal defects.
The graphite furnace heats up by different heating elements, it can separate control temp around the seed area and SiC particles material area .Then we can improve the growth rate when ensuring the crystal quality
Temp Control at Whole Cycle
This technology solves the problem of accurate temperature measurement and control in the high-temperature environment above 2000 ° C.Normally we use infrared Thermometers . However, in the high-temperature environment, volatiles from graphite crucible and SiC particles materials will affect infrared thermometers data, so normally we control the power to estimate the temperature
We separate the crystal grow space and temperature measurement space .So we can control the real temperature when crystal growing,Impove the quality and stable of crystal
High Precision Pressure Control
Pressure control is important for crystal growth. The pressure will affect the gas composition, gas flow uniformity, and crystal growth rate of SiC powder during sublimation.
The common pressure control accuracy is around ± 3Pa. We use our innovation pressure sensor match with a proportional valve to control pressure accuracy ± 0.3Pa (100-500Pa).
Double Coils Technology
We control two coils separately ,one coil controls the temperature of the SiC powder material area and the other one control the temperature of the seed crystal area. The axial temperature gradient during crystal growth can be better controlled. After crystal growth is finished,we can control the temperature of the seed crystal area to do crystal annealing separately.
Heat Radiation Control
We put an auto-run insulation shield above the graphite crucible. Then we can control the heat radiation by rotating the insulation shield.
The crystal growth interface moves downward during crystal growth, We can control the heat radiation to adjust the temperature of the seed crystal area without moving the Coil. Close the heat radiation when the crystal growth is completed to improve the quality of the SIC crystal.
Automation Technology
Instead of manual handling of materials, information intelligent interaction, to achieve a digital intelligent factory
- Auto-run to load and unload the goods.
- Auto-run to level and position by itself.
- AGV+Charging system
- Laser navigation available.
*will launch soon