n and p channel MOSFETs from four bulk CMOS technologies and two CMOS/SIMOX technologies were characterized for total dose response up to 1 Mrad(SiO/sub 2/) at temperatures from 10 K to 120 K. The peak transconductance in the linear region increased in n channel devices and decreased in p channel devices for devices with lightly doped drain (LDD) implants. These changes were much larger as the temperature was decreased and were as much as a factor of 50 in p MOSFETs at 10 K. The one technology without LDD showed only a minor change in and, with dose even at 10 K. The changes in transconductance are most likely a result of hole trapping in the spacer oxide affecting the series resistance. >