Transmission line model (TLM) method study of nanostructural AuGeNi/n-GaAs ohmic contact layer for different substrate deposition temperature

摘要

Because of the importance of ohmic contact in semiconductor devices, in this study, AuGeNi thin films were depositedby thermal evaporation technique at substrate deposition temperaturefrom 80 °C to 230 °C andannealed at the same conditions. Thencontact resistivity and surface morphology was investigated. Surface morphology was investigatedby Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The compositions of different zones have been determined by use of x- ray Energy-Dispersive Spectrum (EDS) analysis. Contact resistivity of the samples is measured using a conventional Transmission Line model (TLM) method. So from the I–V curves and the other mentioned analysis results, it is concluded that the sample which was deposited at 180°C indicates the best electrical and morphological properties.