| 摘要 |
PURPOSE:To obtain the semiconductor device having a capacitor having a large capacitance with small area by forming the capacitor on a groove formed on a semiconductor substrate. CONSTITUTION:A densely diffused layer 4 of the same conductivity type (N<+> type) as an N type epitaxial layer 2 is formed in the layer 2 isolated by insulating through a P<+> type diffused layer 3 in a P type semiconductor substrate 1 as one electrode of a capacitor. A metallic film 6 as the other electrode of the capacitor is confronted through an insulating film 5. Since this capacitor is formed on the groove made on the substrate, its electrode area can be increased so that the electrostatic capacity can accordingly by increased. This groove formed in a V shape on the main surface of the substrate as a <100> plane by utilizing the etching rate of the <111> plane being fast, but a rectangular groove may also be formed on the <111> plane as a main surface. |
