Abstract: An implanter without ion mass analyzer was used to fabricate thin SOI materials by low energy and low dose water ions implantation instead of conventional SIMOX.The result shows that the interfaces between the top silicon,buried oxide layer and bulk silic on are smooth and sharp.XTEM and SIMS results of as-implanted and annealed samples reveal that the thickness of the top Si is dependent on implanting energy at fixed dose,while the BOX thickness independent.Under 50keV implantation energy,the thickness of BOX is relative thin,but more Si islands emerge in the buried oxide layer.The appropriate energy and dose need to be chosen to fabricate desirable SOI structure.