| 摘要 |
PURPOSE:To achieve the miniaturization of a Schottky barrier diode and to improve the accuracy of the diode by forming an annular second electrode around a first electrode on an insulating film. CONSTITUTION:A thin oxide film 4 and a thick oxide film 2 are formed on a semiconductor substrate 1 made of a P-type silicon substrate, and a channel stopper 3 made of a P<+> type impurity diffused layer is formed under the film 2. Then, a polysilicon layer is formed on the films 2, 4, and patterned to form a polysilicon electrode 5 which planely becomes annular. When the film 4 exposed in the annular interior of the electrode 5 is, for example, removed by etching with solution of hydrogen fluoride or the like, the electrode 5 is not etched but performs as a mask, an opening 6 is formed to expose part of the substrate 1. When platinum or the like is then deposited by a depositing method or the like in the opening 6 on the substrate 1 and the electrode 5 and heat treated, a metal electrode 7a made of platinum silicide is formed on the substrate 1, and a metal electrode 7b made of platinum silicide is formed on the electrode 5. Then, unreacted platinum remaining on the oxide 2 is selectively removed by aqua regia. Thus, reverse dielectric strength is improved, a guard ring is eliminated, and a miniaturization is further improved. |
