Patent ID: 8003306

Claim:
A method of forming an electronic device comprising: forming a resist layer over a substrate, wherein the resist layer has a first region, a second region, and a third region, wherein the second region lies between the first and third regions; directing radiation through a reticle to expose the resist layer, wherein the reticle comprises different radiation zones having different transmission values with respect to each other, and wherein the first region of the resist layer is exposed to a different amount of radiation as compared to the second region of the resist layer; removing part of the resist layer to leave a remaining portion, wherein within the remaining portion, the second region of the resist layer is thinner than the third region of the resist layer; and ion implanting the substrate while the remaining portion of the resist layer overlies the substrate to form a first implant region within the substrate and a second implant region within the substrate, wherein the first implant region is deeper than the second implant region.