Browse Prior Art Database

Method for using a chemical mechanical polishing tester for quality control analysis/qualifying of polishing pads and slurries

IP.com Disclosure Number: IPCOM000005061D
Publication Date: 2001-Aug-07
Document File: 5 page(s) / 142K

Publishing Venue

The IP.com Prior Art Database

Abstract

Disclosed is a method for using a chemical mechanical polishing (CMP) tester for quality control (QC) analysis and the qualifying of polish pads and slurries.

This text was extracted from a WORD97 document.
This is the abbreviated version, containing approximately 34% of the total text.

Method for using a chemical mechanical polishing tester for quality control analysis/qualifying of polishing pads and slurries

Disclosed is a method for using a chemical mechanical polishing (CMP) tester for quality control (QC) analysis and the qualifying of polish pads and slurries. Benefits include:

Description

The disclosed method is an analytical technique to establish reliable procedure for pre-selecting the pads and slurries with an acceptable polishing performance before their use in VF for high volume wafer manufacturing.

The key elements of the method include:

Establishment of the difference in polishing rate of certain metal, oxide, dielectric, or any other layers that are used in IC manufacturing, using various pads and/or slurries in in-situ analytical polishing tests.

Differentiating pad hardness in in-situ analytical polishing tests and establishing effect of the said quantity on the polishing rate.

Application of a CMP tester, also known as a tribometer, for characterization of the pad properties

Establishment of the direct correlation between the pad and slurry properties and pad and slurry performance in mass volume production

The disclosed method addresses the problem of uniformity and reproducibility of wafer polishing by the pre-selection of the pads and slurries with the required performance using QC tests of the pads and slurries before mass volume production.

The uniformity and reproducibility of such parameter of the polishing process, the removal rate, is crucial for the degree of surface planarity. However, this parameter can vary even when the same types of pads, slurry, equipment, and polish conditions are used. The pad and slurry manufacturers use different material properties to characterize the pads and slurries. However, the unambiguous relationships between the pad/slurry properties and their polish performance have not conventionally been established. The disclosed method utilizes an analytical procedure that establishes the direct correlations between the pad/slurry properties and their polishing rate. Additionally, the method establishes direct correlation between polishing rate and pad hardness, which is measured in-situ during analytical polishing test.

Conventionally, no solution exists for the problem of establishing an unambiguous relationship between the pad/slurry properties and their polish performance. Numerous material pad and slurry properties are measured by the pad and slurry manufacturers and by various analytical and research laboratories. However, these measurements do not enable an unambiguous pre-selection of the pads and slurries with the required polishing performance before mass volume production.

Mechanical end-point detection was introduced in the early CMP tools. Polishing mechanical resistance was characterized using the electrical output signal that depended on the motor tor...