Pressure dependence of optical emission from DC magnetron sputtering plasma observed with spatial resolution

Optical emission spectroscopy (OES) with a wavelength range of 185-525 nm h as been performed for DC planar magnetron sputtering of copper in argon atm osphere. Spatial resolution of the light emission has been achieved by focu sing the plasma image on one end of an optical fiber. The other end of the fiber is connected to a "polychromator" with linear CCD array sensors, whic h enables an uptake of whole spectrum simultaneously. Several emission line s from Cu neutrals, Ar neutrals and Ar ions have been identified in the obs erved wavelength range. In this study, the emission spectra were measured a t positions of 5 and 10 mm above the center of the Cu target. Dependences o f emission intensities on discharge pressure and power have been studied, a nd the excitation process of Cu radicals is discussed. (C) 2000 Elsevier Sc ience Ltd. All rights reserved.