Method for epitaxy of high electron mobility transistor

A method for epitaxy of a high electron mobility transistor epitaxial structure, comprising:

• providing a substrate;
• forming a nucleation layer on the substrate;
• forming a buffer layer on the nucleation layer;
• forming a first nitride layer on the buffer layer, wherein the first nitride layer is in contact with the buffer layer;
• forming a second nitride layer on the first nitride layer, and performing carbon doping on the second nitride layer, wherein the second nitride layer is in contact with the first nitride layer;
• forming a channel layer on the second nitride layer;
• and
• forming a barrier layer on the channel layer, wherein a two-dimensional electron gas is formed in the channel layer along an interface between the channel layer and the barrier layer;
• forming a third nitride layer on the second nitride layer, wherein the third nitride layer is in contact with the second nitride layer and is located between the channel layer and the second nitride layer;
• the growth temperature of the second nitride layer is less than a growth temperature of the third nitride layer,
• wherein a growth temperature of the second nitride layer is less than a growth temperature of the first nitride layer;
• a film thickness of the first nitride layer is less than a film thickness of the second nitride layer.