In this paper, the influence of nitrous oxide (N2O) nitridation temperatures on p-type Pi-gate (PG) poly-Si junctionless accumulation mode (JAM) TFTs is experimentally investigated. The tetraethoxysilane (TEOS) gate oxide quality for PG JAM TFTs can be significantly improved by increasing N2O nitridation temperatures (TN) from 700 °C to 800 °C in N2O ambient, resulting in the improvement of average subthreshold swing (A.S.S.), increase of on current (ION ), and enhancement of TEOS gate oxide breakdown E -field (EOBD). PG JAM TFTs by means of a proper channel doping concentration (Nch= 5 × 1018 cm-3) and a suitable TN (800 °C) exhibit a steep A.S.S. 96 mV/dec. and a large EOBD ∼ 12.1 MV/cm.