SCANNING TUNNELING MICROSCOPE COAXIALLY ARRANGED WITH AN OPTICAL MICROSCOPE

A newly developed STM has an optical microscope which is coaxially arranged with the tunneling tip. In STM operation, the surfaces of samples can be observed simultaneously with an optical microscope. Furthermore the tunneling tip can be recognized as a shadow image of a submicron dot in the observing area of the optical microscope. The tube scanner with tip holder is arranged in the center hole of the objective lenses. The scanning area of the STM is 20 x 20-mu-m, and the visual field of the optical microscope is about ten times as large as the scanning area, so it is convenient in identifying the region of a surface to be imaged with the STM. The performance of this STM has been demonstrated on the surface of a lithography pattern, and on the atomic images of HOPG.