The strength of the depletion zone electric field increases as the reverse-bias voltage increases. Once the electric field intensity increases beyond a critical level, the p-n junction depletion zone breaks down and current begins to flow, usually by either the Zener or the avalanche breakdown processes. Both of these breakdown processes are non-destructive and are reversible, as long as the amount of current flowing does not reach levels that cause the semiconductor material to overheat and cause thermal damage.
Is there some diodes that behave this way
QuoteIs there some diodes that behave this waySure. Pretty much all diodes can operate "backwards." Zener diodes are a particular type that is DESIGNED to operate that way.
But a zener stops conducting when the voltage drops below the breakdown voltage
but with the reverse emitter-base junction it will continue to conduct if the voltage drops below Vebo
QuoteBut a zener stops conducting when the voltage drops below the breakdown voltageNo, look at the I/V curve of a real device.
Quotebut with the reverse emitter-base junction it will continue to conduct if the voltage drops below VeboAre you sure? There are 4-layer devices that behave that way (tunnel diodes, "sidactors", SCRs in breakdown), but normal reverse-biased single junctions behave more like zeners. The original article you linked is reverse-biasing the CE connection (three layers, I guess...)