Anomalous regenerative switching has been observed in a power V-groove MOSFET with the drain terminal of the MOSFET at the top surface of the chip. This switching phenomenon is attributed to a rectifying junction formed at the drain terminal due to a thin oxide between the drain metal and the n-type drain diffusion. Because of the regenerative switching, the device characteristic changes from the MOSFET I(V) characteristic to a turned-on thyristor characteristic as the gate voltage is increased to a critical voltage. The ON-resistance of the device in the thyristor mode is found to be one-tenth of that in the MOSFET mode. Based on the explanation of the experimental results, an insulated gate controlled thyristor structure with substrate as the cathode is proposed. © 1984.
Bhagat, J. K. (1984). Regenerative switching in V-groove metal oxide semiconductor field-effect transistor structure. Solid State Electronics, 27(5), 441–446. https://doi.org/10.1016/0038-1101(84)90150-3