A combined power transistor structure for improved switching performances

A new power bipolar transistor, named Center-Lightly-Doped-Emitter Gate Associated Transistor (CLDE-GAT), has been developed which combines the base structure of the GAT with a center-lightly-doped emitter structure. The experimental results verify that a properly combined structure may results in combination of advantages of the two structures, i.e. high voltage capability with base width thinner than that of the conventional transistor for the GAT and shorter turn-off time for the latter. And because of the simple fabricating process based on the conventional triple-diffused process, it can be concluded that the new structure transistor is a high-speed high-voltage switching device with low on-voltage and low cost.