The Relationship between 60Co and 10-keV X-Ray Damage in MOS Devices

This paper presents a conduction current technique to separate the effects of fractional charge yield and dose enhancement in metal-oxide semiconductor (MOS) devices in a 1O-keV x-ray environment. The results of the conduction current measurements, together with the concept of charge generation as the damage-producing agent, are used to correlate the threshold-voltage shifts in gate- and field-oxide MOS field-effect transistors irradiated with 60Co and a 10-keV x-ray machine. A straightforward procedure for calculating the equal-damage dose equivalence between the 10-keV x-ray and 60Co sources is also presented.