[OPTICAL REVIEW Vol. 13, No. 4 (2006) 269-275]
© 2006 The Optical Society of Japan

Development of a “Built-in” Scanning Near Field Microscope Head for an Atomic Force Microscope System and Stress Mapping of an Al2O3/ZrO2 Eutectic Composite

Tatsuo NAKAGAWA*, Satoshi FUKURA1, Munenori NAKAI2, Kazumasa SUGIYAMA2, Ryohei KOKAWA3 and Hiroyuki KAGI1

UNISOKU Co., Ltd., Kasugano, Hirakata, Osaka 573-0131, Japan
1Geochemical Laboratory, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
2Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
3Shimadzu Corp., Horiyamashita, Hadano, Kanagawa 259-1304, Japan

(Received November 15, 2005; Accepted January 20, 2006)

We constructed a scanning near-field optical microscope (SNOM) on a commercially available atomic force microscopy (AFM) apparatus (SPM-9500J2; Shimadzu Corp.) to measure the stress distribution in ceramic composite materials. Features of our SNOM system are: (1) a compact SNOM head substituted for the original AFM head; (2) a wide scanning range (125 × 125 μm2) inherited from the original scanner; (3) use of conventional shear-force regulation; (4) an optical system for the illumination-collection (I-C) mode; (5) excitation by a 488 nm line of an Ar-ion laser, and (6) light detection by photon counting or a polychromator equipped with an electronically cooled charge coupled device (CCD). This SNOM system was used to measure the surface structure and stress distribution of an Al2O3/ZrO2 eutectic composite. We simultaneously measured topographic images and fluorescence spectra of an Al2O3/ZrO2 eutectic composite. We estimated its peak intensity, peak position, and peak width from the fluorescence spectrum during scanning, which respectively correspond to the abundance of Al2O3, stress in the grain, and the anisotropy of that stress. Mapping images showed that the stress and its anisotropy were weaker in the center of the Al2O3 grain than its boundary between Al2O3 and ZrO2. That observation suggests that Al2O3 underwent intense anisotropic stress induced by volume expansion in the phase transition of ZrO2 from the cubic phase to the monoclinic phase during preparation.

Key words: SNOM, AFM, mapping of spectral parameters, stress mapping, Al2O3/ZrO2 eutectic composite

*Corresponding author. E-mail address: tatsuo@unisoku.co.jp