| 摘要 |
PURPOSE:To obtain current sensing terminals free of sensing errors by depositing an insulating film thicker than a gate insulating film immediately under that one of gate electrodes which extends over adjacent main unit elements and sensing unit elements. CONSTITUTION:An insulating film 16 which extends over P wells 4, 4 of a sensing unit element QSE and a main unit element QO adjacent to this consists of the gate insulating films 16a, 16b of the same thickness as that of the gate insulating film 6 of the main unit element QO and an insulating film 16b thicker than those films. The thick insulating film 16b spreads over an n<-> epitaxial layer 3 sandwiched by the P wells 4, 4. A gate electrode 7' overlays the insulating film 16 and is coated with an interlayer insulating film 10'. As a result, the thicker the insulating film 16b is formed, the larger parasitic resistance RP becomes so that most of sensed current flowing through the sensing element QSE flows through a sensing resistor RSE; therefore, sensed voltage gets proportional to the ratio of cell count. This structure can provide MOS type semiconductor devices equipped with current sensing elements of less sensing errors. |
