Experimental investigation into impacts of neutron irradiation on pMOS dosimeter behaviors. (February 2023) - Li, Lei
Abstract: The p-channel metal–oxide–semiconductor (pMOS) transistor is a frequently used dosimeter for ionizing radiation, such as γ -rays, since its threshold voltage changes ( Δ V th ) in proportion to the ionization dose. When a pMOS is subjected to γ -ray and neutron radiation fields, the neutrons can influence the Δ V th response to γ -rays. Individual cobalt-60 γ -ray irradiation and sequential irradiation by fission neutrons and subsequent cobalt-60 γ -rays are used to explore the neutron-induced impacts. Experiments show that preceding neutron irradiation can reduce γ -ray sensitivity of Δ V th while accelerating the recovery of Δ V th during the post- γ -irradiation annealing. Additionally, the component of Δ V th induced by oxide charges ( Δ V ox ) is separated from that induced by interface traps as determined by mid-gap tests. This proves that the neutron sensitivity of Δ V ox accounts for that of Δ V th . According to nuclear collision theory, this work suggests that the electronic loss of neutrons rather than the nuclear loss dominates the neutron-induced influences on Δ V th . Highlights: Reports experimental results for preceding neutron induced impacts on pMOS dosimeter. Reports impacts on components of threshold voltage for pMOS dosimeter. Suggest a method to subtract the neutron-induced impacts.