SIMS depth profiles study of WSi structures produced via the silicon reduction of tungsten hexafluoride

Tungsten films were deposited on As- and B-implanted Si substrates by the Si reduction of WF6 at 300°C. The composition of the W/Si structures was investigated by secondary ion mass spectrometry (SIMS). Sputtered W/Si standard structures were used for calibration and to establish the procedure of the SIMS analyses. The depth concentration profiles of Si, W, As, B, O and F atoms in the W/Si structures were determined. These results corroborated the data obtained by Rutherford backscattering spectroscopy and nuclear reaction analyses. The WSi interfaces grown by the Si reduction of WF6 were found to be very rough. The SIMS profiles supported the growth mechanism of the W films based on the pinhole model proposed in the literature.