Crystallization process of high-k gate dielectrics studied by surface X-ray diffraction

Abstract

We have studied the crystallization process of HfO 2 and HfAlO x films using grazing incidence X-ray diffraction (GIXRD) with synchrotron radiation. The HfO 2 and HfAlO x films were grown by atomic layer deposition (ALD) on a chemical SiO 2 interfacial layer. X-ray diffraction (XRD) patterns of the HfO 2 film as-deposited contain not only the monoclinic phase but also the orthorhombic or tetragonal phase. With increasing annealing temperature, the orthorhombic or tetragonal phase decreases and disappears. The HfAlO x film crystallized after annealing at 900 °C. The crystallographic phase was the cubic phase of CaF 2 type.