Method of crystallizing a nitride III-V compound semiconductor layer on a sapphire substrate

A manufacturing method of a semiconductor device using a nitride III-V compound semiconductor layer grown on a sapphire substrate comprising:

• first forming recesses on a major surface of said sapphire substrate, and thereafter growing said nitride III-V compound semiconductor layer on said major surface of said sapphire substrate;
• wherein a buffer layer made of a nitride III-V compound semiconductor is grown on said sapphire substrate while raising the substrate temperature from a first temperature to a second temperature higher than said first temperature, and
• wherein each said recess has a depth not less than 10 nm and a width not less than 30 nm.

A manufacturing method of a semiconductor device using a nitride III-V compound semiconductor layer grown on a sapphire substrate comprising:

• first forming recesses on a major surface of said sapphire substrate, and thereafter growing said nitride III-V compound semiconductor layer on said major surface of said sapphire substrate;
• wherein said nitride III-V compound semiconductor layer is grown directly on said sapphire substrate while raising the substrate temperature from a first temperature to a second temperature higher than said first temperature, and
• wherein each said recess has a depth not less than 10 nm and a width not less than 30 nm.