Semiconductor control element
Abstract
Abstract PURPOSE: To improve cutoff current resistance, by improving the shape of gate- cathode so that a gate-lead-out current pulse for turning off the finally remaining on-region passes the shortest distance. CONSTITUTION: Cathode (N layer) is one region within the dotted line. On a narrow piece (P ++ layer), which is a low-resistance part, cathode (N layer) performs divided opration. The width d of the narrow piece of the effective emitter part is taken the wider the closer it is to the turn-off electrode, and it is made continuously narrower in the direction of moving away from the out-going part Gp (the radial direction). This ratio is determined by the ratio of the resistance of P ++ layer in the radial direction to the resistance of effective N emitter EF in the horizontal direction of P base. In either case, the width of the effective cathode- emitter is made smaller as it moves away from gate electrode leader part GP. By this, the entire surface of the cathode is turned off simultaneously, or the part closer to leader part G is turned off last. COPYRIGHT: (C)1980,JPO&Japio
Inventors
- 👤 Satoshi Ishibashi
- 👤 Tetsuo Sueoka
Bibliographic Details
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