Properties Of Titanium Silicide Thin Films Deposited By APCVD

Low-E coating glass used as building windows that had attracted broad attentionas the continuous national energy conservation policies and the strengthening ofpeople environmental protection consciousness. In this paper, TiSi2and Ti5Si3thinfilms were respectively prepared on glass substrates by chemical vapor deposition atatmospheric pressure using SiH4and TiCl4as the precursors. The influence of moleratio of SiH4/TiCl4, reaction temperature and deposition time on the performance ofthe thin films was investigated by XRD, SEM, FTIR spectromete and UV-Vis,respectively. The results show that:(1) Ti5Si3thin films were successfully prepared with the mole ratio of SiH4/TiCl4changing from1to2. When the mole ratio of SiH4/TiCl4was2, the Ti5Si3crystalphase particles were more compact and the crystalline phases content per unit volumewas higher, as the results of it, the films had lower transmittance, lower sheetresistance and higher infrared reflectivity. C54phase of TiSi2thin films were obtainedwhen the mole ratio of SiH4/TiCl4was3,4or5. With the increase of the molar ratioof SiH4/TiCl4, the content of crystal phases in unit film thickness reduces gradually.The resistivity and transmittance of films increased, but the infrared reflectivitydecreased.(2) Due to the increase of the stack density and the content of crystalline phasesin unit film thickness with the reaction temperature, so the resistivity and visible lighttransmittance of films gradually declined, but the infrared reflectivity of filmsincreased. As the reaction temperature was too high, the crystal nucleation ratedecreased with the increase of growth rate which resulted in the formation of largecrystal particles and the decrease of the stack density of films, so the crystallinephases content per unit volume decreased, and thus the resistivity and thetransmittance of films increased, but the films’ infrared reflectivity decreased. Whenthe reaction temperature was720℃, Ti5Si3films obtained the minimum resisitivityand maximum infrared reflectivity with perfect crystal structure and high stack density. But the minimum resisitivity and maximum infrared reflectivity of TiSi2films was obtained at700℃.(3) With the increase of deposition time, the stack density of films increasedgradually, the resistivity of films decreased gradually, so the infrared reflectivity offilms increased gradually. When the deposition time was too long, the crystal particlesgrew into a large size of crystal structure in a particular direction because of crystalanisotropy, the stack density of films decreased, the resistivity of films increased andthus the infrared reflectivity of films decreased. As the thickness of films increasedwith time, the transmittance of films decreased gradually. When the deposition timereached to120s, the resistivity of Ti5Si3thin films would be the minimum (1.21×10-4·cm) and the maximum infrared reflectivity was up to0.95. But the minimumresistivity of the TiSi2thin film was as low as2.16×10-5·cm, while the infraredreflectivity was the maximum as great as0.93, when the deposition time was90s.