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The first paper dealing with avalanche transistors was Ebers & Miller (1955).The paper describes how to use alloy-junction transistors in the avalanche breakdown region in order to overcome speed and breakdown voltage limitations which affected the first models of such kind of transistor when used in earlier computer digital circuits.
In principle, avalanche breakdown only involves the passage of electrons and need not cause damage to the crystal. Avalanche diodes (commonly encountered as high voltage Zener diodes) are constructed to break down at a uniform voltage and to avoid current crowding during breakdown. These diodes can indefinitely sustain a moderate level of ...
The junction of an avalanche diode is designed to prevent current concentration and resulting hot spots, so that the diode is undamaged by the breakdown. The avalanche breakdown is due to minority carriers accelerated enough to create ionization in the crystal lattice, producing more carriers, which in turn create more ionization.
A unidirectional device operates as a rectifier in the forward direction like any other avalanche diode, but is made and tested to handle very large peak currents. A bidirectional transient-voltage-suppression diode can be represented by two mutually opposing avalanche diodes in series with one another and connected in parallel with the circuit ...
A diode intended for regular operation in the reverse, avalanche breakdown, mode. Used as a voltage reference, noise source, and in certain classes of microwave oscillator device. average rectified value The average value of an alternating current waveform, taking the absolute value of the waveform. The average value is generally different from ...
The mode can be determined by the sign of the threshold voltage (gate voltage relative to source voltage at the point where an inversion layer just forms in the channel): for an N-type FET, enhancement-mode devices have positive thresholds, and depletion-mode devices have negative thresholds; for a P-type FET, enhancement-mode have negative ...
For a device that makes use of the secondary breakdown effect see Avalanche transistor. Secondary breakdown is a failure mode in bipolar power transistors. In a power transistor with a large junction area, under certain conditions of current and voltage, the current concentrates in a small spot of the base-emitter junction.
Snapback is a mechanism in a bipolar transistor in which avalanche breakdown or impact ionization provides a sufficient base current to turn on the transistor. It is used intentionally in the design of certain ESD protection devices integrated onto semiconductor chips.