In this work, we present experimental evidence and analytical studies of
dark current noise spectral density in CdTe detectors for a low and mid
frequency range. The measured noise level in CdTe detectors indicates shot
noise suppression at 10 KHz; this suppression can occur in CdTe detectors
when the diffusion time is greater than the transit time between electrodes.
Moreover we show thermal noise is negligible in CdTe resistors, taking into
account their high resistance: R # 150 G${\rm \Omega} $
.