Effects of BCl3 addition on Ar/Cl-2 gas in inductively coupled plasmas forlead zirconate titanate etching

The lead zirconate titanate (PbZrxTi1-xO3:PZT) ferroelectric thin films hav e received great attention for the applications on nonvolatile memory, infr ared sensor, electro-optical device, microelectromechanical system device, etc. In order to accomplish the integration of these devices, the etching p rocess for both PZT film and electrode material must be developed. In this study, PZT etching was performed using planar inductively coupled Ar(20)/Cl -2/BCl3 plasma. The etch rate of PZT film was 2450 Angstrom/min at Ar(20)/B Cl3 (80) gas mixing ratio and substrate temperature of 80 degrees C. X-ray photoelectron spectroscopy analysis for film composition was utilized. The chemical bond of PbO is broken by ion bombardment, and the peak of metal Pb in a Pb 4f peak begins to appear upon etching, decreasing Pb content faste r than Zr and Ti. Also, the relative content of oxygen decreases rapidly. W e thought that abundant B and BCl radicals made a volatile oxycompound such as BxOy and/or BCl-O bond. To understand the etching mechanism, Langmuir p robe and optical emission spectroscopy analysis were utilized for plasma di agnostic: (C) 2000 American Vacuum Society. [S0734-2101(00)00404-8].