Method for forming high yield epitaxial wafers

A method for forming an epitaxial wafer from a silicon substrate, the method comprising the steps of:

• slicing the substrate to form a wafer;
• annealing the wafer;
• forming an epitaxial layer;
• and
• forming an oxide layer on the epitaxial layer by (a) heating the wafer to a first temperature, (b) removing a portion but not all of the epitaxial layer, (c) placing the wafer in an oxygen atmosphere for a given time period, and (d) gradually reducing the temperature to a second temperature.

A method of forming an epitaxial wafer from a silicon substrate, the method comprising:

• slicing the substrate to form a wafer;
• annealing the wafer;
• forming an epitaxial layer by (a) growing an epitaxial layer, (b) removing a substantial portion but not all, of the grown layer, and (c) regrowing the epitaxial layer to the required thickness;
• and
• forming an oxide layer by (i) heating the wafer to a first temperature, (ii) removing a portion of the epitaxial layer, (iii) placing the wafer in an oxygen atmosphere for a given time period, and (iv) gradually reducing the temperature to a second temperature.