Abstract:
The present invention relates to a turn-off power semiconductor device (1) having a wafer (10) with an active region and a termination region surrounding the active region, a rubber ring (70) as an edge passivation for the wafer (10) and a gate ring (60) placed on a ring-shaped gate contact (40) on the termination region for contacting the gate electrodes of at least one thyristor cell formed in the active region of the wafer. In the turn-off power semiconductor device (1) of the invention, the outer circumferential surface of the gate ring is in contact with the rubber ring to define the inner border of the rubber ring (70). In the invention the area consumed by the ring-shaped gate contact (40) on the termination or edge region can be minimized. The upper surface of the gate ring (60) and the upper surface of the rubber ring (70) form a continuous surface extending in a plane parallel to the first main side (11) of the wafer (10). In a method for manufacturing the device, the gate ring (60) is used as an inner sidewall of a mold for molding the rubber ring (70).
Abstract:
A pole-piece 1 5 for a press-pack type power semiconductor device 10 is described. The pole-piece 15 serves to provide an electrical connection to the semiconductor wafer 2 of the power semiconductor device 10 and to convey heat out of the device. A force F is applied between the two pole-pieces 15, 1 6, to ensure good thermal and electrical contact between the pole-pieces 1 5, 16 and the semiconductor wafer 2. The pole-piece 15 transfers heat away from the semiconductor wafer 2 by means of one or more heat-pipes 12, formed between pillars or walls 1 1 in the body section 13 of the pole-piece. The pillars or walls 1 1 serve both to bear the load of applied force F and to define the lateral bounding walls of the heat-pipe(s) 12 within the body section 13 of the pole-piece 15. A second, similar pole-piece may be deployed on the opposite side of the semiconductor wafer 2. A method of fabricating such a pole-piece is also described.