| 摘要 |
PURPOSE:To obtain a diode with a long inverse recovery time by a method wherein a thickness of a high density layer is regulated in accordance with the kind of metal of a backside electrode and a heat treatment temperature, so that diffusion of the metal into a low density substrate is avoided. CONSTITUTION:N<+> layer 2 are formed by diffusion from both sides of an n<-> type Si substrate and one of the layers 2 is removed by polishing, so that a specular surface is obtained, SiO23 is formed on the specular surface and an aperture 4 is made and a p<+> diffused layer 5 and an SiO2 thin film 6 are formed. An aperture is made in the film 6 and an Au electrode 7 is formed. Then the n<+> layer 2 of the backside is made thinner by etching and an Au electrode 8 is formed and a diode is completed after heat treatment. If the thickness of the n<+> layer 2 is determined in such a manner that Au is not diffused into the n<-> substrate 1 by the heat treatment at 380-400 deg.C, a diode with a long inverse recovery time is obtained and a required recovery time can be obtained in accordance with the thickness of the layer 2. |
