Investigation on the role of oxygen in μc-Si:H thin film and its deposition process with VHF-PECVD

Investigations on the role of oxygen in μc-Si:H films deposited with and without load lock chamber by VHF-PECVD technique have been reported in this paper. From the results of in-situ optical emission spectroscopy (OES), X-ray photoelectron spectroscopy (XPS) and Fourier transformation infrared absorption (FTIR) measurements, it can be identified that oxygen existing in μc-Si:H film with different bonding modes, namely Si-O bonding, O-H bonding and O-O bonding. In addition, the influences of oxygen on the structural and electrical properties of films are studied with Raman spectra, conductivity (σ) and active energy (E_a) measurements. The results reveal the structural properties of μc-Si:H film strongly depends on the bonding modes of the existing oxygen, the electrical properties especially show that the role of oxygen in μc-Si:H films is different from those in a-Si:H and the essential mechanism needs to be further explored.