Radiation Hardness on Submicron NMOS

We have studied the radiation hardness of the submicron NMOS fabricated by electron-beam lithography. E-beam lithography is known to create neutral traps in the gate oxides of MOS devices. These traps may make the devices more sensitive to radiation. We have developed an e-beam NMOS process, and have investigated the electrical characteristics of these devices before and after various radiation doses. We found that, for radiation doses below 10 Krad, the threshold shifts of the MOSFETs are not significant (<100mv). Also, there is no channel-length dependence on radiation hardness with devices made by the present process.