ASTM F399-00a

This standard was transferred to SEMI (www.semi.org) May 2003

1.1 This test method covers the determination of thickness of silicon heteroepitaxial or polysilicon layers deposited under conditions such that the interface region between the deposited layer and the substrate is less than 20-nm thick. Interface regions 20 nm and thicker rarely occur, but are evidenced by a roughness in the originally smooth substrate which can be detected by a profilometer after the thickness measurement is completed and the layer has been etched away.

1.2 This test method is applicable to layers having a thickness in the range from 0.1 to 20 µm, inclusive. Other thicknesses may be measured by the same technique but the expected precisions have not been determined.

1.3 This test method is applicable to silicon layers deposited on any substrate, such as silicon dioxide, sapphire, spinel, etc., that is not significantly attacked by the recommended etch (see 8.3 and 8.4).

1.4 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. Specific hazard statements are given in Section 9.