Electron Energy-Loss Spectrum Imaging of an HfSiO High- k Dielectric Stack with a TaN Metal Gate

摘要

A Si(100)/SiO2/HfSiO/TaN/poly-Si gate stack is investigated using analytical electron microscopy and, in particular, electron energy-loss spectroscopy. Oxygen is shown to be present in the TaN layer and at the TaN/poly-Si interface in the form of oxidised TaN and SiO2, respectively. Phase separation of the HfSiO into crystalline HfO2 and amorphous SiO2 is also observed with a resulting widening of the SiO2 layer.