Ultrathin Al 2O 3 and AlN films deposited by reactive sputter using advanced electron cyclotron resonance plasma source

Abstract

Al 2O 3 and AlN films, with a minimum thickness of 2 nm, were deposited without substrate heating using an advanced electron cyclotron resonance (ECR) plasma source coupled with divided microwaves, and the electrical characteristics of the films were investigated. The uniformity of the film thickness is within ±2% on a 6-in wafer. High resistivity of the order of 10 15 Ω cm and the breakdown voltage of 10 MV/cm are obtained for Al 2O 3 films with thickness from 2 to 40 nm. For AlN films, the resistivity was of the order of 10 14Ω cm with thickness above 5 nm and the breakdown voltage was about 5 MV/cm.