To provide a technique for measuring the track width of writing magnetic head formed on a substrate, orthogonally to the writing direction without cutting it out, namely, from the above with high precision, and also to provide a method for manufacturing a thin film magnetic head by using this technique.
The device is equipped with a lighting optical system for illuminating a light track bottom in a wafer with a light beam, an imaging optical system for forming image of scattering light from the light track bottom, and a measuring part for measuring the dimension of a predetermined portion from a formed image. The lighting optical system emits visible rays, ultraviolet rays or far ultraviolet rays as illuminating light, and is provided with a focusing optical system for focusing an objective lens on the light track bottom. As a result, image measurement of a light track width is made possible with high precision, high stability and high resolution on a wafer, enabling the narrow track width of a GMR head to be measured with high precision.
UTO YUKIO
SASAZAWA HIDEAKI
NAKADA TOSHIHIKO
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