| 摘要 |
PURPOSE:To reduce the unevenness of the concentration of impurities in a diffusion layer by etching the diffusion layer on a semiconductor substrate with application of a resist mask and then by covering the diffusion layer and the exposed surface of the substrate with an insulation layer. CONSTITUTION:A P layer 2 is provided on the N type Si substrate 1 and the resist mask 4' is applied thereto. The P layer 2 is etched by a liquid wherein hydrofluoric acid, nitric acid and acetic acid are mixed and thereby a layer 2' is formed, while the substrate 1 is slightly removed by etching. Next, the mask is removed and the layer 2' and the substrate 1 are covered with an SiO2 film 13. By this method, the resistance of sheet due to the unevenness of the density of the P layer is remarkably reduced. In addition, heating for forming the SiO2 film is conducted only once, which is effective for improving the property of the device and for curtailing the process for manufacturing the same. |
