Thin active layer semiconductor device with high breakdown voltage

摘要

The silicon substrate 1 carries an insulating silicon oxide layer 2 and a very weakly negatively doped (n) monocrystalline silicon wafer 3. The device portion 4 is limited by the insulating layer 5 at the wafer. It has a base portion (B) coated with a bipolar transistor (PIP1) of the device portion with a positive coating (P), and this portion (B) is high with a positively coated (P ⁺ ) base connection (B1). constitutes the applied (n ⁺⁾ emitter (E1). transistor (BIP1) has a base portion (B) has a PN- junction to the side below, and the coated (n ⁺⁾ to very high negative drain connection (D1) It is connected in series with the field effect transistor JFET 1. The device portion 4 is very weakly doped, and the distance from the PN junction 9 to the silicon oxide layer 2 is small, so that the voltage V _E , When V _B , V _D is applied to transistors BIP1, JFET1, portion DP1 is easily depleted by the charge carriers, which prevents breakdown of current between base B and drain connection D1. Transistors BIP1, JFET1 withstand high voltages and have only half the space of substrate 1 where a corresponding previously known transistor is needed.