ANALYZING THE EFFECTS OF SPIN-COATED PHOSPHOSILICATE GLASS ON THE CRYSTALLIZATION PROCESS OF SILICON THIN FILMS DEPOSITED VIA MAGNETRON SPUTTERING

This study investigates the influence of spin-coated phosphosilicate glass (PSG) on the crystallization and electrical properties of silicon (Si) thin films deposited by magnetron sputtering, with a focus on optimizing their structural and electrical properties for potential applications in photovoltaics and microelectronics. The results demonstrate that higher spin-coating speeds lead to thinner and more uniform PSG layers, which in turn promote more efficient phosphorus diffusion and enhance film crystallization. Annealing at 950 °C resulted in enhanced dopant activation, improved crystallinity, and reduced sheet resistance. These structural and phase transformations were systematically analyzed by X-ray diffraction (XRD), providing detailed insight into the evolution of the Si thin films during thermal processing. In particular, the XRD results reveal a clear transition from the amorphous to the polycrystalline state, especially for samples processed at optimized spin speeds and elevated annealing temperatures. Optical characterization further showed that thermal annealing modified the reflectance and transmittance spectra and slightly increased the refractive index and extinction coefficient of the sputtered Si films. Overall, the combination of environmentally friendly spin-on doping with scalable physical deposition techniques represents a promising approach for the development of advanced photovoltaic technologies, offering a viable pathway toward sustainable and efficient device fabrication.

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