METHOD FOR CONTROLLING THRESHOLD VOLTAGE OF FIELD-EFFECT TRANSISTOR

摘要

PROBLEM TO BE SOLVED: To freely vary tensile stress or compressive stress required for each substrate through the formation of insulating films of a fixed thickness, by controlling the energy of ion irradiation on the surface of a semiconductor substrate during the formation of an insulating film, thereby varying the stress on the insulating film. ;SOLUTION: The gate 4, source, and drain 5 electrodes of FET are formed. The threshold voltage of FET is measured on a substrate-by-substrate basis. The value of tensile or compressive stress to be applied to each substrate is determined according to the difference between the measured threshold voltage and a final target threshold voltage. The energy or amount of ion irradiation required during film formation by plasma CVD is determined. An insulating film is formed by plasma CVD using the determined energy or amount of ion irradiation to complete the correction of threshold voltage.;COPYRIGHT: (C)1997,JPO