TEM Characterisation of Nichrome Thin Films

摘要

Nichrome (Ni-20 wt.% Cr) thin film resistors were grown on amorphous silicon nitride coated on GaAs substrate by RF magnetron sputtering technique. These structures, in the as-grown and air-annealed conditions, were characterised by cross-sectional transmission electron microscopy (TEM) technique to evaluate the crystalline nature, crystalline size and interface quality. The nichrome layers were nanocrystalline fcc nickel both in the as grown as well as after air annealing at 250 °C for 90 minutes. The average crystalline size, however, showed a moderate coarsening behaviour. Auger electron spectroscopic (AES) studies showed 4nm thick interface. The resistivity (sheet resistance and temperature coefficient of resistance) behaviour has been explained on the basis of these microstructural observations.