ASTM F1390-97

1.1 This test method covers a noncontacting, nondestructive procedure to determine the warp of clean, dry semiconductor wafers.

1.2 The test method is applicable to wafers 50 mm or larger in diameter, and 100 [mu]m (0.004 in.) approximately and larger in thickness, independent of thickness variation and surface finish, and of gravitationally-induced wafer distortion.

1.3 This test method is not intended to measure the flatness of either exposed silicon surface. Warp is a measure of the distortion of the median surface of the wafer.

1.4 This test method measures warp of a wafer corrected for all mechanical forces applied during the test. Therefore, the procedure described gives the unconstrained value of warp. This test method includes a means of canceling gravity-induced deflection which could otherwise alter the shape of the wafer. The resulting parameter is described by Warp(2) in Appendix X2 Shape Decision Tree in SEMI Specification M1. (See Annex A1.)

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.