| 摘要 |
PURPOSE:To form a high withstand voltage Darlington circuit containing a protective diode on a chip by forming an anode region around the base region on an Si substrate, forming a cathode region at the prescribed distance outside, partly superposing it on both regions through an insulating film, and connecting the anode region and the base region via a conductive film. CONSTITUTION:An N type collector region 12 is formed on the back surface and P type bases 13, 14 and a P type layer 15 are formed on the front surface of an N type Si substrate 11, a suitable interval is further formed outside, and an N type layer 16 is formed simultaneously with emitter layers 17, 18. An SiO2 film 19 is covered, a conductive film 20 is formed corresponding to the region surrounded by the layers 15 and 16, connected to the layer 15, partly superposed on the layer 16, commonly connected to the emitter electrode 24 and base electrode 25 of transistors at drive and output stages, and attached with electrodes 21-23. According to this configuration, a protective diode can be effectively contained therein between the collector and the base of a Darlington circuit without increasing the chip size in the ordinary steps. |
