Do Schottky barrier diodes (SBDs) have reverse recovery time (trr)?

In principle, Schottky barrier diodes have no reverse recovery time. However, there is a slight reverse recovery time due to parasitic capacitance, etc.

When forward-biased, pn junction diodes turn on as electrons, minority carriers, flow into the p-type semiconductor while holes flow into the n-type semiconductor. Since both electrons and holes contribute to device operation, pn junction diodes are called bipolar devices. On the other hand, in the case of an SBD composed of an n-type semiconductor and a metal, majority carriers flow into the metal when the SBD is forward-biased, causing it to turn on. Since only majority carriers contribute to device operation, SBDs are called unipolar devices.
Bipolar devices do not turn off immediately when they are reverse-biased. This is because it takes some time for the excess minority carriers that have been injected across the junction to be swept back into the other side of the junction or recombine. The time required for this diffusion is called reverse recovery time. Reverse current flows through the diode during this period. In contrast, in the case of SDBs, the minority carriers of the n-type (or p-type) semiconductor do not contribute to device operation. Therefore, SBDs exhibit no reverse recovery time. However, considerable surface leakage occurs since SBDs consist of a heterogeneous junction between a metal and a semiconductor. In some SBDs, a pn junction is sometimes used to reduce this leakage. In addition to this, it has parasitic capacitance, so it may have a reverse recovery time, although it is minute compared to a pn junction diode.

Fig. 1 Diode state when forward biased
Fig. 1 Diode state when forward biased
Fig. 2 SiC SBD vs Si pn junction diode  Turn-off waveform
Fig. 2 SiC SBD vs Si pn junction diode Turn-off waveform

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