Dear Deepasree Konduparthi,

Both ASTM (www.astm.org) and SEMI (www.semi.org) have documents to show how to
measure the bow of a wafer.  The appropriate SEMI standards can be found from
the SEMI web site,

www.semi.org,

Once at their web site you can search the standards for items containing the
word bow.

Three of the SEMI standards are:

SEMI MF534-02A, Test Method for Bow of Silicon Wafers
SEMI MF1390-1104, Test Method for Measuring Warp of Silicon Wafers by Automated
Non-Contact Scannning
SEMI MF657-0705 Test method for Measuring Warp and Total Thickness Variation on
Silicon Wafers by Noncontact Scanning.

There are also general articles on measuring bow in several industry magazines,
including Semiconductor International, Solid State Technology, Semiconductor
Manufacturing, and Chip Scale Review.  All of these magazines have web sites and
archival articles.

There are several instruments that can be used to measure the wafer bow, from
microscopes to capacitive instruments and other optical instruments.  The
general articles mentioned from the magazines should give a good summary.

Best regards,

Tom Bristow
Chapman Instruments


-----Original Message-----
From: deepa sree [mailto:[email protected]]
Sent: Wednesday, June 07, 2006 7:10 AM
To: [email protected]
Subject: [mems-talk] Wafer Bow measurement

Can anyone tell me how to measure the bow of a wafer?