Patent ID: 6228750
Filing Date: 2001-05-08
Classification: H01L

Abstract:
A method for selectively doping a semiconductor substrate having a surface including a planar area and a non-planar area including sidewalls, the planar area having a first planar area portion and a second planar area portion, the method comprising the steps of:forming a planar doped layer on the semiconductor surface at the planar area, the planar doped layer not being formed on the sidewalls;forming an oxide material on the planar doped layer over the planar area;applying a coating material comprising dopats over the oxide material to form a dopant material coating; andheating the semiconductor substrate, the oxide material and the dopant material coating for at least a sufficient amount of time to cause the dopants to migrate from the dopant material coating into the semiconductor substrate defined by the non-planar area to form a doped semiconductor region extending from the surface of the semiconductor substrate where the non-planar area is located and into the semiconductor substrate, the oxide layer preventing migration of the dopants into the first planar area portion of the planar area.