Method of producing a high resistivity silicon wafer utilizing heat treatment that occurs during device fabrication

Abstract

A high resistivity wafer which does not exhibit diminishing resistivity after device installation and method of making the high resistivity wafer comprising a) using the CZ method to grow a silicon single crystal ingot with a resistivity of 100 Ω·cm or more, preferably 1000 Ω·cm or more, and an initial interstitial oxygen concentration of 10 to 40 ppma, b) processing the ingot into a wafer, c) determining the total amount of heat treatment required to reduce the interstitial oxygen content of the wafer to about 8 ppma or less, d) determining the amount of heat treatment which will take place during the device fabrication process after wafer fabrication, e) subjecting the wafer to a partial oxygen precipitation heat treatment equivalent to the total amount of heat treatment, less the amount of heat treatment that will occur during device fabrication.

Dependencies are inferred from the claim text.