Ultrathin silicon dioxide ®lms grown by photo-oxidation of silicon using 172 nm excimer lamps

We report the low temperature growth of ultrathin SiO2 ®lms on crystalline Si by photo-oxidation with an array of Xe 2 excimer vacuum ultraviolet (VUV) lamps operating at a wavelength of 172 nm. Ultrathin layers from 1.2 to 3.3 nm thickness were grown at time intervals from 5 to 40 min at 100±4008C at an O2 pressure of 1000 mbar. Growth rates of up to 0.2 nm minÿ1 have been achieved at 4008C, while the chemical bonding of the ®lms has been analysed by Fourier transform infrared (FTIR) spectroscopy and found to be SiO2. The as-grown 3.3 nm ®lms exhibited good dielectric properties, comparible to SiO2 ®lms of identical thickness, grown by RTP at 8008C. # 2000 Elsevier Science B.V. All rights reserved