| 摘要 |
PURPOSE:To enable the estimation of the thickness of a thin film formed on an optically transparent base plate at ion etching time for thinning the film when observing the thicknesswise direction of the film by an electron microscope by inserting suitable semiconductor piece between two equal samples formed with the film. CONSTITUTION:A silicon semiconductor 14 is inserted via adhesives 13, 15 to between equal samples of silicons 12, 16 epitaxially grown on sapphire substrates 11, 17 and symmetrically bonded. Since a light gradually passes a semiconductor of silicon or the like in the vicinity of 1 micron of thickness, the thickness can be estimated, if there is a surface to be etched of several hundreds mum of thickness in case of ion etching. Accordingly, thicknesses of the thin films 12, 16 can be estimated by observing the thickness of the part of the semiconductor 14 bonded in case of ion etching by empolying the semiconductor 14 at the same etching speed as that of the same silicon as the films 12, 16. Since the surfaces of the films 12, 16 are protected by the semiconductor 14 via the adhesives 13, 15, defects of the films 12, 16 at polishing time can be avoided. |
