US 6,617,087 B1 · Use of scatterometry to measure pattern accuracy

Abstract

The present invention provides a system and process for controlling the application of patterned resist coatings in an integrated circuit manufacturing process that employs multiple reticle patterns. One aspect of the invention relates to obtaining scatterometry measurements from a patterned resist and using the measurements to determine whether the correct reticle pattern was employed in forming the patterned resist. According to another aspect of the invention, the reticles are provided with grating patterns in addition to reticle patterns, whereby when the reticles are printed, gratings are formed in the resist. The gratings can be used, with scatterometry, to identify the reticle pattern. The reticles can be configured so that the gratings form in a non-functional portion of a wafer, such as a portion along a score line. Where it is, determined that the correct reticle pattern was not used, corrective action can be taken such as stripping the resist and reprocessing the affected wafers.

Claims7

Dependent claims

An integrated circuit device manufacturing process, comprising:

coating a substrate with a resist;
selecting a reticle from among a plurality of reticles, one or more of which comprises a correct reticle pattern for a current stage in the integrated circuit device manufacturing process, wherein each of the plurality of reticles comprise a reticle pattern and a grating pattern, and wherein each grating pattern uniquely corresponds to and identifies a respective reticle, and wherein the grating patterns are adapted to facilitate identification of the corresponding reticle through scatterometry measurements of gratings formed in the resist from the reticle grating pattern;
selectively exposing the resist to actinic radiation through the selected reticle;
developing the resist to obtain a patterned resist having a reticle pattern portion and a grating pattern portion associated therewith;
obtaining scatterometry data relating to the grating pattern portion of the patterned resist;
determining from the scatterometry data whether the selected reticle comprises the correct reticle of the plurality of reticles for the current stage in the integrated circuit device manufacturing process.

3 more elements

Dependencies are inferred from the claim text.

Use of scatterometry to measure pattern accuracy

Life of this patent

Use of scatterometry to measure pattern accuracy

Life of this patent

Abstract

Claims7