ZnO nanostructures grown on porous silicon substrate without catalyst

ZnO nanostructure is one of the most interesting compound semiconductors due to its enormous potential applications in the electronics and optical devices [1, 2]. In this work, ZnO nanostructures were grown on porous silicon (PS) substrate without any catalyst by a simple thermal evaporation method. It has been found that PS with a rough surface morphology is an ideal growth template for growing ZnO nanostructures without the use of any metal catalysts [1–5]. PS structure was fabricated by using electrochemical etching method in HF/ethanol solution. The morphology of PS sample was investigated by scanning electron microscopy (SEM). The field-emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), Raman and photoluminescence (PL) analysis were used to characterize the as-grown ZnO nanostructures.