Abstract: SOI material was successfully fabr icated by using epitaxial layer transfer of porous silicon.The result of Rutherford backscatte ring spectroscopy and channeling (RBS/C) shows that the crystalline quality of top Si layer is good.Spreading resistance probe technology (SRP) indicates that the resistivity of top silicon layer is uniform and the interface between the top silicon layer and SiO₂ buried layer is very sharp.The effect of silicon type before anodizing on the subsequent steps was also studied.Experimental results show that the porous silicon made from P type Si main tains good crystalline quality.And epitaxial silicon layer with good crystalline quality grew on it by using ultra-vacuum electronic beam evaporation.Furthermore,com paring body silicon,the corrosion rate in HF/H₂O₂ solution with a certain concentration is very high,which ensures the thickness of top Si layer.