To provide a method of accurately and easily adjusting the thickness of two jointed wafers, while polishing the upper layer wafer, measuring the thickness of the wafers using a nondestructive method, and classifying them according to the specifications.
A plurality of mask patterns, with each size for inspecting the thickness of a wafer, are formed on one surface of a silicon wafer, and V-shaped trenches 210, 220, and 230 of various depths, after chemical etching for a fixed time. The residual thickness of the upper layer wafer 1 is measured, depending on the size of an aperture 212 of the V-shaped trenches 210, 220, and 230 appearing as a result of further polishing. Moreover, the wafers are classified according to applied specifications and are presented as constituent components of a microsensor device, a silicon piezometer, and an accelerometer.
GONG SHIH-CHIN
HUANG RUEY-SHING
TSENG CHUNG-YANG
Atsushi Nogami
Yasuo Nara
Etsuko Saito
Katsuyuki Utani
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