Low-Temperature, High-Quality Silicon Dioxide Thin Films Deposited Using Tetramethylsilane (TMS)

Abstract

AbstractSilicon dioxide thin films have been deposited at temperatures from 40°C to 250°C by plasma enhanced chemical vapor deposition (PECVD) using tetramethylsilane (TMS) as the silicon containing precursor. The properties of the PECVD TMS oxides (PETMS-Oxs) were analyzed with Fourier Transform Infrared (FTIR) transmission spectroscopy, BOE and P-etch rates and both current-voltage (I-V) and capacitance-voltage (C-V) electrical characterization. At both 130 °C and 250 °C, deposition conditions were identified which formed high quality as-deposited oxide films. Under the best conditions, unannealed Al/PETMS-Ox/c-Si capacitor structures displayed flat band voltages of Vfb = -2.5 V and breakdown fields (Vbd) in excess of 8 MV/cm. These PETMS-Ox films also show low leakage current densities <10-9 A/cm2 which can be maintained up to fields in excess of 4.5 MV/cm. The PETMS oxide electrical quality and process simplicity combine to make a very attractive oxide deposition technology for low temperature, large area applications.