High-Performance and Low-Temperature-Compatible p-Channel Polycrystalline-Silicon TFTs Using Hafnium-Silicate Gate Dielectric

In this letter, high-performance p-channel polycrystalline-silicon thin-film transistors (TFTs) using hafnium- silicate (HfSiO
_x
) gate dielectric are demonstrated with low- temperature processing. Because of the higher gate-capacitance density, TFTs with HfSiO
_x
gate dielectric exhibit excellent device performance in terms of higher I
_ON
/I
_OFF
current ratio, lower subthreshold swing, and lower threshold voltage (V
_th
) albeit with slightly higher OFF-state current. More importantly, the mobility of TFTs with HfSiO
_x
gate dielectric is 1.7 times that of TFTs with conventional deposited-SiO
₂
gate dielectric.