| 摘要 |
PURPOSE:To prevent the generation of an abnormal condition on the surface of an element which causes deterioration of characteristics of the element by a method wherein the metal layer, consisting of the principal ingredient of a Ta coated on the surface of an element or an Nb, is selectively etched with the prescribed etching solution while irradiating a beam of light on the surface of the metal layer. CONSTITUTION:In the process of electrode formation, for example, an SiO2 film 2 is deposited on the substrate 10 whereon an epitaxial layer 11 was provided and after an aperture has been formed, an AuGe layer 3, a Ta layer 4 and an Au layer 5 are deposited successively. Then, the metal layer, excluding the aperture section which will be used as electrodes 61-64, is selectively etched using the prescribed etching solution and an element is formed. As the etching solution of the Ta layer 4, the mixed solution (mixture ratio by volume of 50:50:1:4, for example) consisting of H2SO4, H2O, H2O2 and HF, is used and an etching is performed while the white light of luminous intensity of 500 luxes, for example, is irradiated on the etching surface. Through these procedures, the generation of abnormal small holes on the SiO2 film of the Hall element can be prevented and the asymmetrical property of an unbalanced voltage can also be reduced. |
