A clustered Insulated Gate Bipolar Transistor (CIGBT) comprising a drift region (24), a P region (20) formed within the n-type drift region, an N well region (22) formed within the P well region (20), a P base region (32) formed within the N well region (22) and a cathode region (36). One or more trenches (40) are formed in the device and configured to longitudinally intersect the drift region (24) and, optionally, the P well region (20) as well as laterally intersecting the base region (32), the N well region (22) and the P well region (20). An insulating film is formed on the inner surface of the trenches (40) and gate oxide is formed on the insulating film so as to substantially fill the trenches and form a gate.