Fundamental connection between hydrogen/deuterium desorption at silicon surfaces in ultrahigh vacuum and at oxide/silicon interfaces in metal-oxide-semiconductor devices
Kg. Cheng et al., Fundamental connection between hydrogen/deuterium desorption at silicon surfaces in ultrahigh vacuum and at oxide/silicon interfaces in metal-oxide-semiconductor devices, J VAC SCI B, 19(4), 2001, pp. 1119-1123
The fundamental connection between electron stimulated desorption (ESD) of
hydrogen (H)/deuterium (D) at silicon surfaces in ultrahigh vacuum and hot-
carrier-stimulated desorption of H/D at the oxide/silicon interfaces in com
plementary metal-oxide-semiconductor (CMOs) devices is presented. The depen
dences of device degradation on carrier energy and current density were stu
died on two generations of CMOs devices. The results suggest that the inter
face degradation in long channel devices is primarily due to the desorption
of HID by high energy electrons through the direct electronic desorption m
echanism, while the multiple vibrational heating mechanism becomes importan
t for ESD of HID in deep submicron devices. By measuring interface trap gen
eration at various stressing conditions in large time scales, we also provi
de experimental evidence to show that, unlike the uniform energy distributi
on of Si-H on silicon surfaces, the disordered interface environment introd
uces a variation of Si-H bond strength at the interface. (C) 2001 American
Vacuum Society.