The concept of Bi-mode Gate Commutated Thyristor-A new type of reverse conducting IGCT

In this paper, a new type of reverse conducting IGCT referred to as Bi-mode Gate Commutated Thyristor (BGCT) is discussed. The concept of the BGCT follows an interdigitated integration approach of an IGCT and Diode into a single structure while utilizing the same silicon volume in both GCT and Diode modes. This results in improved thermal behavior and current capability. The BGCT design concept differs from that of the conventional Reverse Conducting IGCT (RC-IGCT) since in the BGCT, each individual segment is designed either as a GCT cathode or Diode anode. With the aid of 2-D Sentaurus TCAD device simulations, we have compared the static and dynamic characteristics of a 91 mm 4.5 kV BGCT model in both GCT and diode modes with that of the equivalent RC-IGCT and asymmetric IGCT. Furthermore, we have also investigated the BGCT performance by varying the GCT to Diode segments ratio.