Production and characterization of porous silicon via laser-assisted etching: Effect of gamma irradiation

In this research, we investigate that Gamma-rays may be used to affect the morphology of pores and the size of porous silicon. Porous silicon (PS) has been produced from the n-type silicon wafers of (111) orientations with the use of the approach of the laser-assisted etching, the samples have been anodized in a solution of HF:C2H2OH concentration 18%. X-ray diffraction (XRD), Atomic force microscopy (AFM), Photoluminescence (PL) and Raman spectroscopy were utilized for the characterization of morphological, optical and structural characteristics of the PS. Before irradiation, the AFM images reveal a dense and randomly dispersed network of pores that cover the whole surface and it is of varying size and pyramidal form. The pores seem more obvious, distinguish, that has larger diameters after 16 Gy Gamma irradiation. Before and after irradiation, the XRD pattern shows significant < 111 > peaks at 28.3 degrees and 28.6 degrees, respectively, indicating that the structure is cubic. After irradiation with gamma rays, the PL intensity in modified PS samples slight decreased, and the wavelength peaks of the PL spectra shifted to the left. Raman spectra of PS prior to and post the irradiation revealed a highly symmetric band structure. Because of new pores forming inside the first layer of PS the roughness of the samples increases with irradiation indicating that it may be utilized in optoelectmnic applications.