In situ monitoring of the growth of oxide thin films at high oxygen pressure

Abstract

Pulsed laser deposition is a well established deposition technique for oxide thin films and heterostructures. The knowledge and control of the growth processes of oxide materials are important for the fabrication of high-quality epitaxial and heteroepitaxial thin-film structures. Because of the high oxygen pressure during the growth process standard reflection high-energy electron diffraction (RHEED) analysis is not possible. To overcome this problem we have used a two-stage differential pumping system. In this way, the electron path in the high-pressure oxygen atmosphere within the deposition chamber has been reduced considerably. The specular beam intensity of the RHEED system was sufficiently high to allow the observation of intensity oscillations during the growth of oxide materials such as SrTiO3 and La2/3Ca1/3MnO3. In addition to the RHEED investigation the surface morphology of the deposited films has been characterized in situ by ultrahigh-vacuum atomic force microscopy.