Hot-carrier effects in polysilicon emitter bipolar transistors

The degradation of self-aligned, polysilicon emitter transistors is described for a wide range of constant current stress on several device sizes. The experimental results indicate that Delta I/sub B/ can be expressed as AQ/sup n/, with n=0.5 for these devices. Except for large values of I/sub R/, A varies in a power-lay fashion with I/sub R/. The dependence of Delta I/sub B/ upon the forward current at which the device is operating can be expressed as A=BJ/sup gamma //sub C/. It is observed that n is characteristic of all devices and stress currents, B is constant for a given device size, and gamma varies with device size and reverse current.<
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