High reverse voltages can be produced in inductive circuits as well.
However, the anode film can only withstand a small reverse voltage.
Avalanche diodes are designed to break down at a well-defined reverse voltage without being destroyed.
This current is almost independent of the reverse voltage.
By changing the amount of reverse voltage, the size of the depletion zone changes.
But it does has some current leakage with reverse voltage.
The breakdown starts when reverse voltage is applied.
In general, the higher the reverse voltage the higher the gain.
Some higher-voltage designs are available; 200V is considered a high reverse voltage.
This often limits the useful reverse voltage to well below the actual rating.