Method and apparatus for monitoring of slurry consistency

Abstract

A method and apparatus for performing online monitoring of a physical characteristic of a process material. A request to provide a slurry to a processing tool is received. The slurry is transported through a slurry transport unit, based upon the request, to the processing tool. An online monitoring of a physical characteristic of the slurry is performed. The online monitoring of the slurry includes analyzing an optical signal sent through the slurry to determine whether the physical characteristic of the slurry is within a predetermined level of tolerance.

Description

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 60 / 486,387, filed Jul. 11, 2003, the entire contents of which are incorporated herein by reference.[0002] 1. Field of the Invention[0003] This invention relates to supplying chemicals for manufacturing processes and, in particular, to an apparatus and a method for performing online monitoring of the consistency of a chemical slurry.[0004] 2. Description of the Related Art[0005] The technology explosion in the manufacturing industry has resulted in many new and innovative manufacturing processes. Today's manufacturing processes, particularly semiconductor manufacturing processes, call for a large number of important steps. These process steps are usually vital, and therefore, require a number of inputs that are generally fine-tuned to maintain proper manufacturing control.[0006] The manufacture of semiconductor devices requires a number of discrete process steps to create a packaged semicondu...

AI Technical Summary

Problems solved by technology

Disruption or changes in the physical characteristic of the slurry may cause errors and misprocessing of various processes, such as CMP processes, performed on the semiconductor wafers.

However, the technology provided by U.S. Pat. No. 6,275,290 has various drawbacks.

Furthermore, if a slurry were undergoing a simultaneous change in the level of suspended solids and a change in particle size distribution, the method disclosed in U.S. Pat. No. 6,275,290 would be unable to distinguish the root cause of such change, since the light transmission at various wavelengths specified in this patent would be affected by such changes.

Hence, this method would not be an efficient and accurate quantifier of a change in suspended solids alone.

Also, the presence of other species in the slurry, such as oxidizers (like H.sub.2O.sub.2) and organic acids (like benzotriazole) will affect the light transmission at certain wavelengths in the method.

The state of the art generally lacks an efficient and accurate assessment of the slurry for use in various wafer-processing steps.

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