Oxides are etched with a halide-containing species and a low molecular weight organic molecule having a high vapor pressure at standard conditions, where etching is performed at preset wafer temperature in an enclosed chamber at a pressure such that all species present in the chamber, including water, are in the gas phase and condensation of species present on the etched surface is controlled. Thus all species involved remain in the gas phase even if trace water vapor appears in the process chamber. Preferably, etching is performed in a cluster dry tool apparatus.