value by this zero bias 34 radiation induced annealing 34 ria process illustration of this annealing effect is shown in fig1 and 2 an sos transistor as utilized in the present invention is a prior art device which may be purchased from several leading semiconductor manufacturers in fig1 the radiation response of two n channel sos transistors is compared with i l versus dose co 60 being shown for a wet gate oxide device and a dry gate oxide device respectively irradiations were performed with the gate source voltage v gs equal to zero and a drain source voltage v ds equal to five volts but leakage current measurements were performed with v gs approximately equal to 7 volts to avoid measurement of front channel current this was accomplished by switching v gs from zero to 7 volts for a time long enough approximately two seconds to measure i l and then switching back to zero volts the general shape of the wet oxide data is similar to that fordry oxide with saturation in leakage current being observed for doses u2267 10 5 rads in both cases an analysis of the data suggests thathole trapping centers in the sapphire responsible for the increase.