Anomalies in transistor low-frequency noise

Accurate low-frequency noise measurements over the range of 1 Hz to 10 kHz on a number of different transistor types showed that the majority obey the f
^-α
-law, the factor α being between 0.96 and 1.23. Certain samples, however, exhibited an additional noise component with a frequency dependence of the form [1 + (f/f
0
)
²
]
^-1
.