Silicon doping and N2 annealing effects on Zn3N2 thin film transistors

Zn3N2 has high mobility >100 cm(2)V(-1)s(-1), but its intrinsic carrier concentration (10(18)-10(20) cm(-3)) has limited its application as thin-film transistor active material. In this work, Si-doped Zn3N2 (ZSN) thin-film transistors (TFTs) were fabricated by magnetron sputtering and annealed in N-2 ambient. The influences of Si doping content, annealing temperature and active layer thickness on ZSN TFTs were investigated. It was found that annealing temperature up to 250 degrees C improved the performances of ZSN TFTs. The threshold voltage (V-th) positively shifts along with improving subthreshold swing (SS) as Si doping content increases. Moreover, further SS improvement was observed by reducing active layer thickness. The ZSN TFT with overall optimal performances exhibited typical V-th of 1.4 V, on-off current ratio of 2.9 x 10(6), subthreshold swing of 0.86 V.dec(-1) and field-effect mobility of 0.69 cm(2)V(-1)s(-1). Finally, the bias stress stability and the influence of oxide passivation on ZSN TFTs were investigated.

Automated summary

Si-doped Zn3N2 thin-film transistors (TFTs) were fabricated and investigated, showing improved performance in terms of mobility and on-off current ratio.