摘要 |
In a bipolar double-poly transistor comprising a layer of base silicon (1') on a silicon substrate (2'), a first layer of silicon dioxide (3') on the base silicon layer (1'), an emitter window (4') extending through the first layer (3') of silicon dioxide and the base silicon layer (1'), a second layer (5') of silicon dioxide in the emitter window (4'), silicon nitride spacers (6') on the second layer (5') of silicon dioxide in the emitter window (4'), and emitter silicon (9') in the emitter window (4'), an isolating silicon nitride seal is provided to separate the base silicon (1') from the emitter silicon (9') to prevent short-circuiting between the base silicon (1') and the emitter silicon (9') in the transistor.
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