Fin-based laterally diffused structure having a gate with two adjacent metal layers and method for manufacturing the same

Abstract

A structure includes a semiconductor fin; a first source/drain region and a second source/drain region in the semiconductor fin; a first doping region about the first source/drain region, defining a channel region in the semiconductor fin; and a second doping region about the second source/drain region, defining a drain extension in the semiconductor fin. A gate structure is over the channel region and the drain extension. The gate structure includes a gate dielectric layer, a first metal layer adjacent a second metal layer over the gate dielectric layer, and a contiguous gate conductor over the first metal layer and the second metal layer. One of the metal layers is over the channel region and the other is over the drain extension. The metal layers may have different thicknesses and/or work functions, to improve transconductance and RF performance of an LDMOS FinFET including the structure.