CyberOptics Semiconductors (www.CyberOpticsSemi.com) has published an application note on its web site explaining how its WaferSense® Auto Gapping System (AGS) has helped a 300 mm fab increase the availability of a plasmaenhanced chemical vapor deposition (PECVD) tool.

The Auto Gapping System replaced a legacy gapping method that took 10 hours to measure the distance between the chamber’s gas showerhead and wafer pedestal to ensure uniform film deposition, particularly with newer dielectric films. In addition to being imprecise, the gapping method was dangerous and increased exposure to particle contamination as techs repeatedly opened and handled the hot PECVD chamber.

CyberOptics AGS offered a safer, more precise gapping method that significantly reduces the time associated with characterizing the chamber. Configured with three capacitive sensors in a wafer-like form factor, the Auto Gapping System measures the distance to a conductive electrode in three locations on the showerhead and returns realtime gap measurements to a GUI. Companion software enables the exportation of gapping data as a CSV file.

In addition to eliminating exposure to contaminants, the Auto Gapping System enables the PECVD team to measure a range of possible gaps and set gaps with an accuracy of up to a thousandth of an inch to meet tight film deposition and production tolerances at the 300 mm fab. After a twomonth evaluation of the wireless gapping method, the team reported that the wireless method reduced the time to maintain the PECVD chamber’s gap settings from 10 to 4 hours or less – a reduction of 60 percent.

For details on how the WaferSense Auto Gapping System increased tool uptime for a 300 mm fab, go to:

http://www.cyberopticssemi.com/content/files/resources/ec-csi-ags-casestudyAJedits3-4-10.pdf

Detailed information on CyberOptics’ WaferSense products is available online at http://www.cyberopticssemi.com/products or by contacting sales at (503) 495-2200 for more information.