Low-frequency noise of ion-implanted double-drift IMPATT diodes

The low-frequency open circuit noise spectral density S(f) of an ion-implanted 60-GHz double-drift-region IMPATT diode was measured as a function of the dc avalanche current I
0
. Over an intermediate current range the noise follows an S(f)=a
²
V
B0
²
/I
0
relationship where V
B0
is the reverse breakdown voltage and a
²
≃4.5 × 10
^-20
A/Hz.