Formation of Zn-Containing Clusters in Implanted Si₃N₄ Film

The results of the synthesis and study of Zn-containing clusters at the interface of a Si₃N₄/Si film implanted with ⁶⁴Zn⁺ ions with a dose of 5 × 10¹⁶ cm^–2 and an energy of 40 are presented. The Si₃N₄ film was preliminarily deposited on a silicon substrate from chemical vapor. Then, the implanted samples 10 × 10 mm in size were annealed in an oxidizing atmosphere (in air) with a step of 100°C for 1 h at each step in the temperature range 400–800°C. To study the profiles of zinc during annealing, the Rutherford backscattering method was used. The structure and composition of the film were studied using scanning electron microscopy in combination with energy dispersive spectroscopy, as well as photoluminescence. After implantation, individual clusters of metallic zinc with a size of about 100 nm or less were recorded near the surface of the Si₃N₄ film. It has been established that, during annealing, Zn clusters grow in the sample and the phase of metallic Zn gradually transforms into phases of its oxide ZnO and then, presumably, Zn₂SiO₄ silicide. After annealing at a temperature of 700°C, which is the most optimal for obtaining the ZnO phase, zinc oxide сlusters about 100 nm in size are formed in the Si₃N₄ film. A peak appears in the photoluminescence spectrum at a wavelength of 370 nm due to exciton luminescence in zinc oxide. After annealing at 800°C, the ZnO phase degrades and, presumably, the zinc silicide phase Zn₂SiO₄ is formed.