Patent ID: 11942521
Assignee: INNOSCIENCE (SUZHOU) SEMICONDUCTOR CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 17:
18. A method of forming a semiconductor device, comprising:
providing a substrate;
forming a first transition layer on the substrate at a first temperature;
forming a second transition layer on the first transition layer at a second temperature greater than the first temperature;
forming a third transition layer on the second transition layer at a third temperature greater than the first temperature;
forming a fourth transition layer on the third transition layer at a fourth temperature greater than the first temperature;
forming a first III-nitride layer on the fourth transition layer; and
forming a second III-nitride layer having a band gap energy greater than that of the first III-nitride layer on the first III-nitride layer,
wherein a fourth transition layer is sandwiched between the third transition layer and the first III-nitride layer,
wherein the second transition layer has a minimum aluminium molar ratio among the first transition layer, the second transition layer and third transition layer; and the fourth transition layer has an aluminium molar ratio smaller than that of the third transition layer.