Estimation of density changes associated with growth in vacuum-deposited amorphous films of antimony

Amorphous antimony films consisting of separate islands were deposited onto SiO_x and GeO_x film substrates at room temperature in a vacuum of 10^-5 Torr. By comparison of the interferometrically determined thickness and the total mass of incident vapour determined with a quartz oscillator, it was found that a sudden change in film density occurs at a certain film thickness d₀. Another change in film density, which is gradual, occurs in the vicinity of a certain thickness $\text{d}{}_{\mathrm{<mtext>c</mtext>}}\text{(d}{}_{\mathrm{<mtext>c</mtext>}}\text{\&\#62; d}{}_{\mathrm{<mtext>0</mtext>}}\text{)}$. The change at d₀ is caused by the coalescence of neighbouring islands. The change at d_c, at which the coalescence of amorphous islands is almost completed, is associated with crystallization.