On 1/f noise characteristics for 0.1 eV HgCdTe photoconductors

Abstract

Sensitivities on 0.1 eV HgCdTe photoconductors with new electrode configuration and in different sizes were measured at 77K and under 10¹⁴phcm⁻²s⁻¹ photon background conditions. After data for responsivity, generation-recombination noise (g-r noise) and minority carrier lifetime were reproduced by solving a one dimensional diffusion equation on excess minority carrier, discussions on 1/f noise were made and the following characteristics were concluded: (1) 1/f noise does not originate near electrodes for bias current. (2) 1/f noise hardly depends on sensor size and temperature in the 77–95K range, while g-r noise does. (3) 1/f noise is proportional to bias electric field, i.e. current density. (4) 1/f noise does not depend on photon background. From characteristics (2) and (4), it was concluded that 1/f noise has nothing to do with g-r noise. Finally, a new empirical formula was proposed for 1/f noise.