Single component pad backer for polishing head of an orbital chemical mechanical polishing machine and method therefor

Abstract

A pad backer for a polishing head of an orbital chemical mechanical polishing (CMP) machine is formed of a flexible pad. A plurality of holes are formed through the flexible pad. The holes are used to accommodate tile flow of a polishing liquid from the underside of the flexible pad. A plurality of grooves are formed on a backside of the flexible pad for transferring a liquid during the polishing process.

Description

RELATED APPLICATIONS [0001] This patent application is claiming the benefit of the U.S. Provisional Application having an application number of 60 / 578,987, filed Jun. 11, 2004, in the name of Harvey Pinder, and entitled “SINGLE COMPONENT PAD BACKER FOR POLISHING HEAD OF AN ORBITAL CHEMICAL MECHANICAL POLISHING MACHINE”.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to an orbital chemical mechanical polishing machine, and more particularly, to a new single component flexible pad backer for the polishing head of an orbital chemical mechanical polishing machine. [0004] 2. Description of the Prior Art [0005] Chemical mechanical polishing is utilized in the fabrication of a semiconductor wafer in order to planarize both dielectric and metallization layers within the semiconductor wafer. The uniformity or planarization of each layer is critical for several reasons. A planar layer reduces the step height to facilitate the subsequent photol...

AI Technical Summary

Benefits of technology

"The present invention provides a new single component flexible pad backer that overcomes the problems associated with conventional multi-component pad backers. The single component flexible packer design increases flexibility, resulting in a more desirable level of uniformity of the polished surface layer of a wafer. It also increases the useable life of the packer and eliminates the need for a screen or mesh material to be placed between the air bladder and pad backer. The design incorporates channels or grooves for liquid transport into the backside of the pad backer."

Problems solved by technology

Additionally, a planar layer reduces the likelihood of accidental coupling of active conductive devices between different metallization layers.

The conventional multi-component pad backer design reduces the flexibility of the pad backer through the use of the metal plate that the urethane is portion of the pad backer is mounted to.

By reducing the flexibility of the pad backer, the planarization efficiency or uniformity of the polished surface layer of the wafer is affected.

In the conventional multi-component pad backer, the usable life of the pad backer is reduced due to the metal plate bending or deforming to the point that a planar or uniform surface on the wafer cannot be achieved.

Furthermore, users of the conventional multi-component pad backer have noted that the glue layer between the urethane and metal portions of the pad backer breaks down during use and results in delaminating of the pad backer.

Either of these situations has a negative impact of the planarization of the wafer surface and renders the pad backer unusable.

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