摘要 |
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 OMEGA.cm or more, preferably 1000 OMEGA.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.
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