Radiation Hardness of a-Si H FETs

In a recent paper French et al. (1983) investigated the effect of y radiation on the properties of a-Si H FETs by exposing devices to doses of up to 5 Mrad (Si). The notation implies that this energy is absorbed in the a-Si film. 

In the present study (French et al., 1983) a series of FETs with closely matched characteristics were irradiated at room temperature using a dose rate of 0.17 Mrad (Si) hr-1. The first group received a y-ray dose of 1 Mrad, the second of 5 Mrad. Each included devices held during irradiation at VG values of—8 V, — 5 V, 0 V, + 5 V, and + 8 V with respect to the source and 

On the basis of the present experiments, it is concluded that a-Si H FETs are remarkably resistant to the effect of radiation, despite the relatively thick dielectric layer used at present in these devices. 

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