Fabrication of semiconductor device using alternating high and low temperature layers
View Patent ↗A method for fabricating a III-nitride semiconductor body that includes high temperature and low temperature growth steps.
1. A method of fabricating a semiconductor device, said method comprising:
providing a silicon substrate; and
growing a III-nitride body over a major surface of said substrate to a final thickness over a growth period of time,
wherein growing said III-nitride body comprises growing at least two AlN layers including a first AlN layer and a second AlN layer grown directly on said first AlN layer, and growing a superlattice over said second AlN layer, said first AlN layer grown during a period of low temperature growth at a first temperature, said second AlN layer grown on said first AlN layer during a period of high temperature growth at a second temperature, and said superlattice grown at a constant temperature,
wherein said first temperature is lower than said second temperature.
2. The method of claim 1 , wherein a number of layers grown at said second temperature is equal to a number of layers grown at said first temperature.
3. The method of claim 1 , further comprising forming a buffer layer over said III-nitride body.
4. The method of claim 3 , further comprising forming an active layer over said buffer layer, said active layer providing an active region for fabricating a power FET.
5. The method of claim 1 , wherein said second temperature is constant over said growth period of time.
6. The method of claim 1 , wherein said first temperature is constant over said growth period of time.
7. The method of claim 1 , wherein said period of high temperature growth is varied.
8. The method of claim 1 , wherein said period of low temperature growth is varied.
9. The method of claim 1 , wherein said period of high temperature growth and said period of low temperature growth are varied.
10. The method of claim 1 , wherein said period of high temperature growth is equal to said period of low temperature growth.
11. The method of claim 1 , wherein said period of high temperature growth is different than said period of low temperature growth.