Patent ID: 8247870

Claim:
A method for fabricating an integrated circuit (IC), comprising: fabricating a transistor of controller circuitry and a switch on a same semiconductor substrate for said IC, wherein said controller circuitry is operable for controlling said switch, and wherein said fabricating of said transistor and said switch comprises: forming a first P-well for said switch on said same semiconductor substrate; forming a second P-well and an N-well for said transistor on said same semiconductor substrate; forming a first polygate for said switch on said first P-well; forming a second polygate for said transistor on said second P-well and said N-well; implanting N-type dopants in said first P-well to form an N-type double diffused (NDD) layer for said switch after formation of said first polygate; implanting N-type dopants in said NDD layer to form a first N-type heavily doped (N+) layer for a drain of said switch, wherein said first N+ layer is surrounded by said NDD layer; implanting N-type dopants in said first P-well to form a second N+ layer for a source of said switch; implanting N-type dopants in said N-well to form a third N+ layer for a drain of said transistor; and implanting N-type dopants in said second P-well to form a fourth N+ layer for a source of said transistor.