Electrical Characterisation of Gate Dielectrics Deposited with Multipolar Electron Cyclotron Resonance Plasma Source

Abstract

Silicon oxide films have been deposited by plasma-enhanced chemical vapour deposition, at glass compatible temperatures. A multipolar electron cyclotron resonance plasma (ECR) source with SiH4/He and N2O was used. The electrical properties of the films were determined by means of C-V and I-V measurements. The dependencies of the electrical properties on gas-flow ratio and pressure were investigated. Critical electric fields as high as 6 MV/cm and net oxide charge densities as low as 1×1011 ions/cm2 have been obtained for the optimal deposition conditions. The oxide integrity versus CVD conditions was investigated by charge to breakdown measurements. MOSFETs have been fabricated in order to test the dielectric quality.