Fast switching lateral insulated gate transistor

Abstract

The switching speed of the Lateral Insulated Gate Transistor (LIGT) is slow compared to that of similar LDMOS power devices. The LIGT described in this paper, however, is designed to have both fast, switching and high current conduction. The speed improvement is achieved by using a modified LIGT structure, where an additional n <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> region is added to the p <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> injector. The turn-off time of this modified LIGT is less than 450 nanoseconds, while turn-on is under 100 nanoseconds. Computer simulation is used to understand the role of the shorted anode in improving the switching speed of the LIGT. A comparison with fabricated devices is shown to be in good qualitative agreement.