The effect of ZnO:Si3N4 nanocomposite interlayer on electrical properties and interface-states between metal-semiconductor in Al/p-Si (MS) structures

Abstract

In the study, the fabrication processes of the Al/p-Si (MS), Al/ZnO/p-Si (MIS1), and Al/(ZnO:Si3N4)/p-Si (MIS2) structures were described and the effect of the ZnO:Si3N4 interface layer in MS was investigated in detail. The ZnO and (ZnO:Si3N4) thin films were coated on p-Si substrates and annealed at 500 °C for 1 h. Si3N4 and ZnO phases were identified via X-ray diffraction (XRD) and Raman spectra. FESEM images demonstrated that ZnO nanorods grew on Si3N4 particles with a heterogeneous nucleation mechanism. The I–V characterization was performed in the dark (±4 V). The basic diode parameters (barrier height (BH), series/shunt (Rs/Rsh) resistances, rectifying rate (RR=If/Ir), and ideality factor (n)) were calculated from various methods. The RR, and Rsh values increased, but n, Rs and BH decreased by insulating layer in the MIS2 The energy-dependent profiles of interface-states (Nss) were also extracted from the I–V plots according to voltage-dependent n and BH. The MIS2 provided the best passivation effect with decreasing interface traps.