Semiconductor Sealing Solutions
Moore’s law, named after Intel and Fairchild Semiconductor founder Gordon Moore, predicted that the density of integrated circuits, or chips, would double every two years. For 50 years that prediction has been met through breakneck innovation in manufacturing processes and equipment. What allows for this continued advancement in wafer construction? In a word, purity.
Like many sealing applications contamination is the enemy of sealing performance. In typical industrial sealing applications contamination is measured in millimeters, in the semiconductor industry it is measured in microns.
This pursuit of environmental purity causes unique semiconductor sealing challenges. Various wafer-fabricating operations; such as deposition, etch, ash/strip, thermal and wet, utilize caustic chemicals at extreme temperatures. Traditional elastomers don’t stand a chance in these environments.
To meet these challenges materials such as Kalrez™, a DuPont Performance Elastomers product, were developed. Kalrez™ is part of a family of highly fluorinated materials. These compounds will perform where other traditional materials fail, and extend planned maintenance schedules that maximize equipment up-time and increase total cost of ownership.
New materials continue to develop in this area. Lower particle generation and longer seal life are the byproducts of this innovation. Consult Gallagher engineers on your OEM or aftermarket semiconductor sealing application.
When the seal has to be right, Gallagher Delivers.
Application Case Study 1: Bonded Door Seals
Problem: Standard O-ring profiles installed in traditional groove shapes were producing high levels of particle generation and eventually contamination.
Cause: O-Rings installed in gate valves, or slit valve dovetail grooves have ‘Dead-Space’ within the grooves. Over time particles generated from application wear will accumulate within this dead space causing contamination into the deposition chamber.
Solution: Molding the exact same O-Ring elastomer into the gate removes the O-Ring groove, and the corresponding dead space. This profile also improves the wear characteristics of the seal, and extends life and time between maintenance.
Application Case Study 2: Outgassing
Problem: Small molecules originating from seal degradation find their way into the deposition processing chamber, in addition to decreasing vacuum pump performance.
Cause: Elevated temperatures cause fluorine-containing fragments within the elastomer to outgas into the chamber.
Solution: High performance FFKM materials, such as Kalrez™ 9100, are polymeric filled. This offers reduced potential for particle degradation. Furthermore, the compound is cross-linked using a proprietary curing system providing strong thermal stability while reducing outgassing at elevated temperatures.