Patent ID: 7829408

Claim:
A method for fabricating a laterally double-diffused metal oxide semiconductor transistor (LDMOS), comprising: providing a substrate comprising a first conductive dopant; forming a first well comprising a second conductive dopant in a part of the substrate; forming a second well comprising a first conductive dopant in another part of the substrate; forming a plurality of field oxide films (FOXs) on a top surface of the substrate, wherein a first FOX and a second FOX thereof are located in the first well, and a third FOX thereof is located in the second well; forming a gate structure on a part of the substrate and a part of the second FOX; forming a drain in the first well; forming a source in the second well, the source comprising a lightly doped region and a heavily doped region extending downwardly from the top surface of the substrate, wherein in the step of forming the source comprising the lightly doped region and the heavily doped region, the depth of the lightly doped region is more than the depth of the heavily doped region and the third field oxide film contact with the lightly doped region and is separated from the heavily doped region by a distance.