| 摘要 |
PURPOSE:To obtain an insulated separation layer having a reduced bird beak and a good crosssectional configuration by forming a selective oxide layer being heat-oxidized after providing a plasma anode oxidizing process by using a resistance oxidized mask consiting of three layers. CONSTITUTION:On a Si substrate 11, is formed a selective oxidizing mask consisting of three layers of pad SiO2 film 12, Si3N4 film 13 and alumina film 14. Subsequently, an oxide film is formed thinner than a predetermined thickness in a separation region through a plasma anode oxidizing method, and successively a separation oxidized film 15 is grown at a predetermined thickness through a high temperature heat oxidizing method. Accordingly, a slight bird beak caused in the heat oxidizing process makes a section of the separation layer gentle and consequently the separation structure which is not much extended widthwise and can prevent disconnection of a wiring can be easily obtained. |
