Atomic Layer Deposition of ZrO2 Thin Films Using Dichlorobis[bis-(trimethylsilyl)amido]zirconium and Water

A new zirconium precursor, (ZrCl2[N(SiMe3)2]2), and H2O oxidant were used to deposit ZrO2 films on a Si substrate, for alternative gate dielectrics, via atomic layer deposition (ALD) in the temperature range 150–350 °C. The film growth showed the self‐limiting characteristic of ALD, with a maximum growth rate of 1.6 Å per cycle at 175 °C. The compositions of as‐deposited films were analyzed by Rutherford backscattering spectroscopy (RBS), X‐ray photoelectron spectroscopy (XPS), and secondary ion mass spectroscopy (SIMS), and it was found that the amount of silicon in ZrO2 films was uniformly distributed throughout the film in the range of 1.1 at.‐% to 5.4 at.‐% as the deposition temperature was increased. After rapid thermal annealing in an Ar atmosphere at 700–900 °C, the amorphous as‐deposited film was crystallized mainly in the cubic phase, and no significant change in surface morphology was observed. A novel zirconium precursor for ALD of ZrO2 is introduced. The ALD characteristics of zirconia on Si using dichlorobis[bis(trimethylsilyl)amido]zirconium and water are studied as a function of deposition temperature. The film growth shows self‐limiting characteristics with maximum growth of 1.6 Å cycle–1 achieved at 175 °C. The composition of the as‐deposited amorphous films are analyzed by RBS, XPS, and SIMS, and the amount of Si in ZrO2 films is found to be in the range of 1.1– 5.4 at.‐%. On rapid annealing in Ar at 700–900 °C, the deposited films are crystallized, mainly in the cubic phase, with no significant change in surface morphology.