Noise Properties Of High Resistivity Cl‐doped Cadmium Telluride

Investigation of noise properties of CdTe:Cl samples with specific resistivity in the range ρ ≈ 10⁸ – 10⁹ Ωcm at room temperature were performed. Cadmium telluride single crystals with chlorine concentration in the range N_Cl = 10¹⁷ – 5 × 10¹⁹ cm⁻³) were grown by sublimation traveling heater method (STHM). Noise spectra have been measured over a wide range of frequencies, from below 1 Hz up to 1 MHz, and for voltages applied the samples from 0 up to 200 V. Two type of noise dominates in the range of voltages and frequencies under investigation, namely excess 1/f noise and generation‐recombination (G‐R) noise. Analyses of short noise were performed taking into consideration the presence of the macrodefects and clusters (inclusions and precipitates) in the crystalline matrix. It is assumed that these types of inhomogeneities affect the current noise spectra especially in highly doped material (N_Cl > 10¹⁹ cm⁻³).