LDMOS device and method of fabrication of LDMOS device

A method of fabricating a lateral double diffused metal oxide semiconductor (LDMOS) device, comprising the steps of:

• (a) providing a substrate of a first conductivity type;
• (b) implanting a first element in the substrate to form a well region of a second conductivity type;
• (c) implanting a second element in the well region to produce a super steep retrograde (SSR) well in which a doping concentration changes with depth so as to provide a lighter doping concentration in a surface region of the SSR well than in a region below the surface region of the SSR well;
• (d) forming a gate layer which partly overlies the well region and is insulated from the well region;
• and
• (e) forming one of a source region and a drain region in the well region, while maintaining the SSR well profile in portions of the well region on opposing sides of said one of the source region and the drain region.

A method of fabricating a lateral double diffused metal oxide semiconductor device on a substrate having a first conductivity type, comprising the steps of:

• forming within the substrate first and second well regions, with the first well region having the first conductivity type and the second well region having a second conductivity type and a super steep retrograde well profile, with the super steep retrograde well profile being absent from the first well region and sections of the substrate in superimposition therewith;
• forming a gate layer which is in superimposition with both the first and second well regions and spaced apart therefrom by dielectric material;
• and
• forming one of a source region and a drain region in one of the first and second well regions.