FLUORESCENCE SIGNAL DETECTION FOR OPTICAL MICRO-THREE DIMENSIONAL MEASUREMENT BASED ON CONFOCAL MICROSCOPY

Masaki Michihata, Ayano Fukui, Kenji Maruno, Terutake Hayashi, Yasuhiro Takaya

Abstract

We newly propose the optical micro-coordinate measurement technique based on the fluorescent signal. Surface position is detected based on fluorescent signal emitted from surface of structures by means of the confocal optical detection. Stimulated fluorophore emits fluorescence over wide angular ranges, allowing the confocal microscope to gather the fluorescent signal from steep surface (even from vertical sidewall). Thus this optical method is expected to measure three-dimensional shapes of smaller structures than 100 µm. Previously we reported the detection capability of a vertical surface based on the fluorescent signal with the confocal optical system. This paper deals with feasibility of three-dimensional measurement of micro-structures. Firstly, characteristic of detecting surface with various tilted angles were measured. As a substrate, the flat silicon wafer coated with the fluorescent dye thin film with a thickness of a few micrometers was used. Experimental result shows that the horizontal (0 deg.), vertical (90 deg.) and also undercut surface (120 deg.) could be successfully detected. At next, a cross-sectional shape of a metal wire was measured. A diameter of the wire was about 1 mm. The wire was also coated with fluorescent dye thin film. The result showed that the cross-sectional profile of the wire could be measured although the accuracy could not be ensured yet. We concluded that the proposed method manage to measure three-dimensional shapes of micro-structures.

Keywords

dimensional measurement, optical probe, fluorescence, confocal microscopy

Download

IMEKO-TC14-2014-25.pdf

DOI

-

IMEKO TC

TC14 - Measurement of Geometrical Quantities

Back to the proceedings