Inductively coupled plasma etching of a Pb(ZrxTi1?x)O3 thin film in a HBr/Ar plasma
The etching of Pb(ZrxTi1?x)O3 (PZT) thin films was performed using HBr/Ar gas in an inductively coupled plasma. The etch rate and etch profile of the PZT films were investigated as a function of the gas concentration of the HBr/Ar mixture. In addition, the etch parameters, including coil power, dc bias and gas pressure, were examined to characterize the etching process of the PZT films. An enhancement of the etch rate with increasing gas concentration was found, which indicates that PZT etching by HBr/Ar follows the reactive ion etching mechanism. It was found that the maximum etch rate and selectivity for Pt films was around 40% HBr under the etch conditions used in this study. From X-ray photoelectron spectroscopy (XPS) analysis, it was observed that the Pb component in PZT solid solution showed a faster etching than the Zr and Ti components. The etch rate and the degree of anisotropy of the PZT films were enhanced by increasing the coil power and dc-bias voltage, and by lowering the gas pressure. An etch rate of 900 /min and a steep etch profile of >70 could be achieved with HBr/Ar chemistry.
inductively coupled plasma pb(zrxti1?x)o3 thin film hbr/ar gas high-density etching