Method for precision oxidation control by ion implantation

A method of processing a semiconductor substrate, the method comprising:

• performing a first ion implantation process on the semiconductor substrate, wherein a first ion beam formed of an ionized first dopant species is directed at a top surface of the semiconductor substrate and wherein a mask disposed on the top surface shields a first portion of the semiconductor substrate from the first ion beam while allowing the first ion beam to impinge upon and implant a second portion of the semiconductor substrate;
• removing the mask from the top surface of the semiconductor substrate;
• performing a second ion implantation process on the semiconductor substrate, wherein a second ion beam formed of an ionized second dopant species is directed at the top surface of the semiconductor substrate, including the first portion and the second portion, wherein an effect of the second ion implantation process on an oxidation rate of the second portion counteracts an effect of the first ion implantation process on the oxidation rate of the second portion;
• removing the mask from the top surface of the semiconductor substrate;
• performing an oxidation process on the semiconductor substrate, wherein a layer of oxide having a uniform thickness and uniform height is formed on the first and second portions of the semiconductor substrate;
• removing the layer of oxide from the semiconductor substrate, whereafter the semiconductor substrate is left with a planar surface extending across the first and second portions of the semiconductor substrate;
• and
• forming an epitaxial layer on the semiconductor substrate, wherein the epitaxial layer has a uniform thickness and uniform height extending across the first and second portions of the semiconductor substrate.