Study of the characteristics of photoresistors based on hydrochemically deposited films of Pb$_{0.902}$Sn$_{0.098}$Se solid solution

Experimental samples of photoresistors based on a Pb$_{0.902}$Sn$_{0.098}$Se-solid solution semiconductor films obtained by the layer-by-layer deposition of individual selenides of lead and tin(II) with subsequent thermal activation are developed. The structure and morphology of the thin-film compositions (SnSe–PbSe)$_2$ are studied. The temperature dependences of the dark resistance, signal, noise and its ratio, as well as the frequency and spectral characteristics of photoresistors fabricated on the basis of Pb$_{0.902}$Sn$_{0.098}$Se films in the range of 205–300 K are studied. The optimal bias voltages are determined. It is shown that the location of the maximum and the right boundary of the photoresponse for Pb$_{0.902}$Sn$_{0.098}$Se-based photoresistors is shifted, in comparison with PbSe, toward the long-wavelength region by 0.7 $\mu$m. The maximal detectivity of the studied photoresistors (2.0 $\times$ 2.0 mm) obtained at 230 K was 9 $\times$ 10$^9$ cm W$^{-1}$ Hz$^{1/2}$. The advantages of using the Pb$_{0.902}$Sn$_{0.098}$Se-based photoresistors in the spectral range of 3.0–5.5 $\mu$m compared with PbSe-based ones are shown.