Charateristics of Low Temperature High Quality Silicon Oxide by Plasma Enhanced Atomic Layer Deposition with In Situ Plasma Densification Process

Abstract

We have researched low temperature silicon oxide (SiO2) with improved electrical properties and excellent film step-coverage. In-situ O2 plasma densification (DENSIFICATION) effect on SiO2 that has been deposited by PE-ALD at temperature (<400°C) was investigated. The wet etch rate was controllable as a function of DENSIFICAION time due to repairing of the SiO2 network defects by the oxygen radicals. Angle Resolved X-ray Photoelectron Spectroscopy (AR-XPS) analysis was carried out to observe the core-level binding energies shifts (chemical shifts) in the different SiO2 films. The characteristics of wet etch rate of high quality low temperature SiO2 demonstrated lower than high temperature LP-CVD SiO2 values. Compared to LP-CVD SiO2, PE-ALD SiO2 with DENSIFICATION showed excellent I-V characteristics with lower leakage current and similar to the thermal SiO2 carrier transport plot.