Changing of surface properties of silicon plates under mechanical influence of ultrasonic frequency
Abstract
The work relates to alternative energy technologies, in particular, solar energy. The study discusses the results of changing the optical parameters of silicon wafers after the impact of ultrasonic frequency machining on their surface. Monocrystalline silicon plates of p-type conductivity, used as a base material for the manufacture of solar cells with a flat p-n transition, were chosen as the object for experiments. Mechanical processing of the ultrasonic frequency of the surface of silicon wafers was performed using a special device. Measurements of the surface roughness and the coefficient of light reflection from the surface, depending on the wavelength of incident light, were performed before and after the ultrasonic frequency machining. Based on the obtained LSM images and the surface roughness assessment, as well as the measurement of the light reflection coefficient, the authors proposed a texturing mechanism. Based on the experimental results obtained on the change in the lifetime of photogenerated charge carriers and the spectral dependence of the light reflection coefficient, as well as the physical justification of the processes of light absorption in plates subjected to surface machining of ultrasonic frequency, a new method for improving the efficiency of silicon solar cells has been developed and recommended for practice.