In situ optical diagnosis of pulsed laser deposition and oxidation of YBa2Cu3O7-delta thin films

Laser light (670 nm) was polarized and impinged on YBa2Cu3O7-delta (YBCO) films during their growth by pulsed laser deposition and subsequent oxidation. By simulation of the light reflectance variation, the refractive index (n) and extinction coefficient (k) of the growing films were determined together with the deposition rate. A reflectance change was also observed during cooling the deposited films and was attributed to the increase in oxygen content in the film by comparison with in situ. X-ray diffraction data. Furthermore, the ortho-tetra phase transition could be detected in situ by this method. Thus, the reflectance measurement of p-polarized light was verified to enable in, situ characterization of optical properties and oxygen nonstoichiometry of oxide films during their pulsed laser deposition.