Wide bandgap material in drift well of semiconductor device

A method of forming a semiconductor device comprising:

• forming a drain region in a semiconductor material of a semiconductor substrate;
• forming a source region in the semiconductor material of the semiconductor substrate;
• and
• forming a drift well laterally between the drain region and the source region, the drift well including a wide bandgap material, the wide bandgap material having a bandgap energy that is larger than a bandgap energy of the semiconductor material of the semiconductor substrate,
• wherein the wide bandgap material interfaces with the semiconductor material at a bottom surface and at linear sidewall surfaces.

A method of forming a semiconductor device comprising:

• forming a first gate electrode structure over a first gate oxide layer and a first local oxidation of silicon (LOCOS) structure;
• forming a first drain region in a semiconductor material of a semiconductor substrate;
• forming a first source region in the semiconductor material of the semiconductor substrate, the first gate oxide layer and the first LOCOS structure being disposed laterally between the first drain region and the first source region;
• and
• forming a first drift well, at least in part, laterally between the first drain region and the first source region, the first drift well including a wide bandgap material, the wide bandgap material being disposed underlying the first LOCOS structure, the wide bandgap material having a bandgap energy that is larger than a bandgap energy of the semiconductor material of the semiconductor substrate,
• wherein the wide bandgap material interfaces with the semiconductor material at a bottom surface and at linear sidewall surfaces.

A method of forming an integrated circuit, comprising:

• forming a first laterally-diffused metal-oxide-semiconductor (LDMOS) transistor in or over a semiconductor layer, the LDMOS transistor comprising:
• a drain region disposed in a semiconductor material of a semiconductor substrate;
• a source region disposed in the semiconductor material of the semiconductor substrate;
• and
• a drift well disposed laterally between the drain region and the source region, the drift well including a wide bandgap material, the wide bandgap material having a bandgap energy that is larger than a bandgap energy of the semiconductor material of the semiconductor substrate,
• wherein:
• the wide bandgap material includes silicon carbide (SiC);
• a concentration of carbon in the silicon carbide increases from an interface between the semiconductor material and the wide bandgap material vertically along a direction to a peak carbon concentration;
• and
• a concentration of carbon in the silicon carbide decreases vertically along the direction from the peak carbon concentration.