Structural and optical properties of Zn-implanted silica: effect of fluence and annealing

The phase-structural composition of silica films grown on Si substrates implanted with different fluences of Zn ions has been studied using transmission electron microscopy (TEM) and electron diffraction. Small clusters (2-3 nm) and larger clusters (5-7 nm) were formed in the as-implanted silica films with Zn concentration of 6-8 at % and 16%-18%, respectively. Furnace annealing at 750 & DEG;C for two hours in air resulted in the formation of an orthorhombic Zn2SiO4 phase (space group R-3) in the case of low fluence (5 x 10(16) cm(-2)) and in the formation of a zinc blended ZnO phase (space group F-43m) in the case of high fluence (1 x 10(17) cm(-2)). Based on the Rutherford backscattering spectrometry (RBS) data, it has been shown that impurity losses during implantation and subsequent annealing increase with the fluence of the implanted ions. The photoluminescence data were consistent with the TEM and RBS.