semiconductor processing
- November 28, 2017
NEW White Paper Available!
Gallagher Fluid Seals recently added a new white paper to its Resources Page, Perfluoroelastomers for the Semiconductor Industry, written by Russ Schnell. Below is an excerpt from the new white paper discussing the key reasons to choose perfluoroelastomers over fluoroelastomers for semiconductor manufacturing. You can download the white paper in its entirety by clicking on the thumbnail to the right.
Perfluoroelastomers (e.g. Kalrez® parts), often replace fluoroelastomer (e.g. Viton®) in semiconductor applications. However, even though perfluoroelastomers are the highest performance elastomers, there are still subtle differences between products. It is suggested that the elastomer supplier be contacted regarding the optimum product and seal design for specific applications. As mentioned above the key characteristics of perfluoroelastomers include:
- Lower offgassing than other elastomers, especially at temperatures above 200°C, which lowers the risk of product contamination.
- Better sealing force retention (lower compression set) at temperatures over 200°C, which is critical for longer service.
Best overall chemical resistance of any elastomer family. - Formulations with extremely low particle generation in aggressive process environments.
- Generally higher gas permeation than fluoroelastomers.
- Higher coefficient of thermal expansion when compared to fluoroelastomers. Proper seal design will account for this and optimize performance.
- October 17, 2017
NEW White Paper Available!
Gallagher Fluid Seals recently added a new white paper to its Resources Page, Perfluoroelastomers for the Semiconductor Industry, written by Russ Schnell. Below is an excerpt from the new white paper discussing thermal process manufacturing. You can download the white paper in its entirety by clicking on the thumbnail to the right.
The term “thermal process” covers a fairly wide range of applications. Per the name, these application temperatures are generally higher than plasma processes, ranging up to 300°C. This general term can cover processes including: Sub Atmospheric Chemical Vapor Deposition (SACVD), Metal CVD, Low Pressure CVD (LPCVD), Rapid Thermal Processing (RTP), and Oxidation or Diffusion furnaces. In these applications the wafers and the equipment that surrounds them, are heated to extremely high temperatures. In the case of thermal deposition, the high temperatures aid in the uniformity of the coating thickness.
Rapid Thermal Processing is used to very rapidly heat a wafer up to temperatures of 1000°C or greater for short periods of time. “Rapid Thermal Processing (RTP) can be used to reduce the thermal redistribution of impurities at high temperature…. RTP was originally developed for ion implant anneal, but has broadened its application to oxide growth, chemical vapor deposition, and silicidation.” For oxidation or diffusion furnaces, the applications are different, but still involve high temperatures. For oxidation applications, the procedure involves formation of a thin oxide film on the wafer surface. For diffusion applications, the furnace may assist in silicon dioxide formation on the wafer surface or it may be used to diffuse dopants in the wafer. For these applications, temperatures may range up to 1200°C.
- September 05, 2017
Purity is critical to high wafer yield, and Kalrez® seals are designed with properties that help reduce contamination from particulates, outgassing and extractables.
In a number of fabrication customer evaluations, Kalrez®seals exhibited improved mechanical strength, lower particle generation and longer seal life versus competitive perfluoroelastomers, in both static and dynamic sealing applications.
Operational Improvements
Kalrez® seals can help improve semiconductor manufacturing in a range of wafer-fabricating operations, including:
- Deposition
- Etch
- Ash/strip
- Thermal
- Wet