Method and apparatus for measuring thickness of a thin oxide layer

Abstract

A method and an apparatus for measuring thicknesses of ultra-thin gate oxide layers are provided. In the method, a substrate that has a thin gate oxide layer formed on top is first heat treated at a temperature between about 400° C. and about 800° C. under a sub-atmospheric pressure for at least 10 seconds. The substrate is then immediately transferred, i.e., within 10 minutes, to a thickness measuring device for the accurate measurement of the thickness of the gate oxide layer. The apparatus can be provided by mounting a heating chamber juxtaposed to a thickness measuring device, such as an ellipsometer so that substrate can be immediately transferred therein between after a heat treatment step is completed. The heat treatment step of the present invention novel method is efficient in preventing the deposition of moisture and organic residue onto the surface of the thin gate oxide layer.

Dependencies are inferred from the claim text.