Nanometer-scale crystallization of thin HfO2 films studied by HF-chemical etching

Abstract

We used a HF-chemical etching process to examine crystalline structures in thin HfO2 films grown by metal organic chemical vapor deposition at 350–550°C. Nanometer-scale crystalline HfO2 nuclei were identified from all the HfO2 films. The nucleus density exponentially increased with increasing deposition temperature, but the diameter of the nuclei did not depend on the deposition temperature. We propose that the crystallization of thin HfO2 film during growth proceeds in a patchwork process with the increase of the crystalline HfO2 nuclei.