Patent ID: 8900954
Filing Date: 2014-12-02
Classification: H01L

Abstract:
1. A method comprising: implanting a well implant into a substrate such that said well implant extends laterally between shallow trench isolation regions and is shallower in depth than said shallow trench isolation regions; patterning a mask on said substrate above said well implant, said mask having an opening that exposes a channel region of said substrate; forming a conformal dielectric layer on said mask and to line said opening, said conformal dielectric layer covering said channel region of said substrate; forming a conformal gate metal layer on said conformal dielectric layer; implanting a compensating implant through said conformal gate metal layer and said conformal dielectric layer into said well implant in said channel region of said substrate, said compensating implant extending vertically through said well implant to a lower portion of said substrate below said well implant; forming a gate conductor in said opening on said conformal gate metal layer; removing said mask to leave a gate stack on said substrate; forming sidewall spacers on said gate stack; and forming source/drain regions in said substrate, extending laterally from said shallow trench isolation regions to partially below said sidewall spacers, and extending vertically through said well implant into said lower portion of said substrate below said well implant, said source/drain regions being separated from said compensating implant by portions of said well implant and said portions of said well implant being partially below said gate stack.