Scalable MOS field effect transistor

A method of forming a field effect transistor comprising the steps of:

• selecting a substrate of single crystal semiconductor material,
• forming a first layer on said substrate of heavily doped semiconductor material compositionally different from said substrate to provide a different etching rate with respect to said substrate,
• forming a second layer of insulating material,
• forming an opening through said first and second layers exposing said substrate for forming a gate dielectric,
• forming a gate dielectric on said substrate in said opening and over the sidewalls of said opening,
• forming a conductive layer on said gate dielectric in said gate opening and on said sidewalls of said opening, and
• patterning said conductive layer to define a gate electrode,
• said first layer on opposite sides of said gate electrode corresponding to the source and drain of said field effect transistor.

A method of forming a field effect transistor comprising the steps of:

• selecting a substrate of single crystal'semiconductor material,
• forming a metal layer on said substrate, said metal layer including material suitable for forming a Schottky metal-to-semiconductor barrier and having a selected work function,
• forming an insulating layer over said metal layer,
• forming a gate opening in said insulating layer to expose said metal layer,
• heating said metal layer in said gate opening above a selected temperature for a time period in a gaseous ambient to react said metal layer and constituents in said gaseous ambient to form a gate dielectric in said gate opening on said substrate,
• forming a conductive layer on said gate dielectric in said gate opening, and
• patterning said conductive layer to define a gate electrode,
• said Schottky metal-to-semiconductor barrier on opposite sides of said gate electrode corresponding to the source and drain of said field effect transistor.

A method for making an FET comprising:

• selecting a semiconductor substrate having a layer of dielectric thereon,
• etching a gate window in said layer of dielectric exposing said substrate,
• selectively growing germanium on said substrate in said gate window wherein no germanium has grown on said layer of dielectric,
• using the germanium as a mask, implanting shallow regions of dopant ions to form the source and drain,
• removing said germaniun,
• forming a gate oxide in said gate window,
• forming a layer of conductive material on said gate oxide and on said layer of dielectric, and
• patterning said layer of conductive material to form a gate.

A method of forming a field effect transistor comprising the steps of:

• selecting a substrate of single crystal semiconductor material,
• forming a metal layer on said substrate, said metal layer including material suitable for forming a Schottky metal-to-semiconductor barrier and having a selected work function,
• forming an insulating layer over said metal layer,
• forming a gate opening in said insulating layer to expose said metal layer,
• forming a gate dielectric in said gate opening by oxidation of said metal layer,
• forming a conductive layer on said gate dielectric in said gate opening, and
• patterning said conductive layer to define a gate electrode,
• said Schottky metal-to-semiconductor barrier on opposite sides of said gate electrode corresponding to the source and drain of said field effect transistor.

A method of forming a field effect transistor comprising the steps of:

• selecting a substrate of single crystal semiconductor material,
• forming at least one conductive layer on said substrate, said at least one conductive layer including a metal suitable for forming a Schottky metal-to-semiconductor barrier and having a selected work function,
• forming an insulating layer over said at least one conductive layer,
• forming a gate opening in said at least one conductive layer and said insulating layer,
• forming a gate dielectric in said gate opening,
• forming a second conductive layer on said gate dielectric in said gate opening, and
• patterning said second conductive layer to define a gate electrode,
• said Schottky metal-to-semiconductor barrier on opposite sides of said gate electrode corresponding to the source and drain of said field effect transistor.