Plasma Grown Oxy-Nitride Films for Silicon Surface Passivation

Abstract

This letter investigates the potential of a low-temperature plasma grown silicon oxy-nitride (SiO x N y ) film for surface passivation of silicon surfaces. Using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, the film composition is studied to identify the process condition for obtaining a smooth Si-SiO x N y interface. D it in the order of ∼10 10 eV −1 cm −2 , is obtained on capping the SiO x N y with a silicon nitride (SiN v :H) film, followed by annealing at 550°C for 2 s. A surface recombination velocity of 50 cm/s is obtained for the SiO x N y -SiN v :H stack when annealed at 400°C for 2 s. The growth of an interfacial SiO x N y prior to SiN v :H deposition is found to improve the thermal stability of the silicon nitride passivation. The stack could be an interesting option with further optimization for surface passivation of n-type surfaces in mono-and multicrystalline silicon solar cells.

Optimization of a Solution-Processed TiOx/(n)c-Si Electron-Selective Interface by Pre- and Postdeposition Treatments

“…Second, there is a reduced stretch-out of the high-frequency capacitance along the voltage axis after annealing. The occurrence of stretch-out is attributed to the presence of interface traps. − The elimination of hysteresis and the sharp transition from the inversion to accumulation regions (and vice versa) after annealing can therefore be ascribed to the suppression of slow defect sites and interface trap density brought about by promoted chemical passivation. While negative V fb and positive Q f of −0.44 V and 4.84 × 10 11 cm –2 were calculated for the annealed sample, respectively, the high current leakage across the device precluded the extraction of D it via conductance-based methods to quantify the chemical passivation level.…”