Influence of vacuum rapid thermal annealing on the properties of μPCVD SiO 2 and SiO 2·P 2O 5 films

Abstract

The effect of the rapid thermal annealing (RTA) on the properties of SiO 2 and SiO 2·P 2O 5. (phosphor silicate glass) is presented. The films have been prepared by micro pressure chemical vapor deposition (μPCVD) technique. The precursors used for the deposition of the films were SiH 4, O 2 and PH 3. The substrate temperature during the deposition was 430°C. The RTA was carried out in vacuum at 800–1400°C for different times of 15–180 s. The samples were characterized by infrared (FTIR) spectroscopy and by measurement of the etching rate of the layers. Both analyses show that the RTA leads to densification of the layers. The etching rate increases with the increase of the temperature and the duration of annealing. The etching rate of the phosphor silicate glass remains about 5% greater than the etching rate of the silicon dioxide. The FTIR spectra show that the RTA shifts the SiO 2 peak closely to the peak of the melted silica, which is at 1100 cm −1.