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Indexed by:期刊论文

Date of Publication:2013-09-23

Journal:Advanced Materials Research

Included Journals:EI、CPCI-S、Scopus

Volume:797

Page Number:561-565

ISSN No.:9783037858257

Key Words:Large and thin silicon wafer; Gravity-induced deflection; Warp measuring equipment; FEM; Air bearing stage

Abstract:Larger diameter wafers are used to decrease the cost of IC manufacturing and the wafer thickness is decreasing for form factor and thermal power dissipation considerations. The larger wafer requires a large scanning area to inspect the warp, and warp measurement of large and thin silicon wafers is greatly affected by the gravity-induced deflection. In this paper the gravity-induced deflection was calculated using finite element method by supporting the wafer horizontally with three steel balls. A laser displacement sensor based on triangulation principle was used to measure the warp and an air bearing stage was developed to achieve high straightness. The shape of the wafer was obtained using the silicon wafer warp measuring equipment.