Deposition and Characterization of Metalorganic Chemical Vapor Deposition ZrO2 Thin Films Using Zr(Thd)4

Excellent quality ZrO2 thin films were successfully deposited on single crystal silicon wafers by metalorganic chemical vapor deposition (MOCVD) at reduced pressures using tetrakis(2,2,6,6—tetramethyl—3,5—heptanedionato) zirconium, [Zr(thd)4]. For substrate temperatures below 530°C, the film deposition rates were very small (≤ 1 nm/min). The film deposition rates were significantly affected by: (1) source temperature, (2) substrate temperature, and (3) total pressure. As—deposited films are stoichiometric (Zr/O = 1/2) and carbon free. Furthermore, only the tetragonal ZrO2 phase was identified in as—deposited films. The tetragonal phase transformed progressively into the monoclinic phase as the films were subjected to high temperature post—deposition annealing. The optical properties of the ZrO2 thin films as a function of wavelength, in the range of 200 nm to 2000 nm, are reported. The measured value of the dielectric constant of the as—deposited ZrO2 films is around 19 in the frequency range of 5 kHz to 1000 kHz.