Irradiation of electronic memory circuits I am investigating the radiation hardness of electronic memory circuits (EEPROM). The following measurement has been performed:
Beam set-up: 
Irradiation occurred perpendicular to the DUT (device under test). The distance between the DUT and a 60Co source was 16 cm leading to a dose rate of 100 Gy/h. The average photon
energy of 60Co is 1.25 MeV. The lateral dimensions of the beam are approximately
4 x 4 cm².
Single Irradiation dose was 20 (krad(Si)). The circuit passed a total dose of 200 Gy.
Now I got a request if the circuit would survive an X-ray with the following specification:
100 keV, 40 uA for a time span of 1-2 minutes
Who could help me with a detailled calculation ? 
 A: The damage done by ionizing radiation to EEPROMs, which are in essence metal-oxide-semiconductor devices (MOSFETs), is mainly due to the charges (electrons, holes) produced by the ionizing radiation which are captured on traps in the volume, at the interface of the insulator and on the floating gate of the devices. These captured/produced charges change the electrical characteristics of the devices and eventually lead to device failure. Furthermore, these charges can also lead to the generation of new traps in the devices which enhances the effects and can lead to increased leakage currents through the insulators. The gamma-ray radiation of 1.2 MeV is more than 10 times more energetic than the the 100keV X-ray radiation. This, however, does't not necessarily mean that there is more radiation damage done in the device. One could try to look up and compare the ionization rates for the involved materials at the different photon energies. In the question essential information is missing, in particular the radiation dose achieved by the x-ray machine cannot be derived from the current.At least data on the absorbed dose (Gy/h) would be needed to make any intelligent guesses about the radiation effects on the devices at the different photon energies.        
