Electron induced deposition and in situ etching of CrOxCly films

In a 3 keV electron system, we have studied both electron beam induced CrOxCly deposition using precursor CrO2Cl2 and electron beam induced etching of as-deposited CrOxCly film using Cl2. The CrO2Cl2 pressure, 6.5 × 10−5 Torr, was experimentally observed to be a threshold for CrOxCly deposition. The Cr film is a composite of Cr, O and Cl with a ratio of Cr:O:Cl = 1:2.2:1.1, and under electron beam irradiation, O increases while Cl decreases. As-deposited CrOxCly films can be etched in situ by chlorine at a pressure of 6 × 10−4 Torr with an electron flux of 10 mA cm−2, demonstrating that Cl2 pressure is the key in initiating the etching reaction.