Patent ID: 6727157
Filing Date: 2004-04-27
Classification: H01L

Abstract:
A method for fabricating a shallow trench isolation, comprising the steps of:sequentially depositing a silicon oxide layer, a silicon nitride layer and a moat pattern on a silicon substrate; etching the silicon nitride layer and the silicon oxide layer using the moat pattern as a mask to thereby partially expose the silicon substrate and then removing the moat pattern; performing ion implanting process into the silicon substrate using the silicon nitride layer as a mask, adjusting a dose of an implanted ion and an implant energy, to thereby form an isolation region; anodizing the isolation region to form a porous silicon and to form an air gap in the porous silicon, wherein a porosity of the porous silicon is determined by the dose of the implanted ion; oxidizing the porous silicon through an oxidation process; and removing the silicon nitride layer.