Ion-plasma treatment of Cd$_{1-x}$Zn$_x$Te ($x\sim$0.04) single crystals and application of antireflection diamond-like carbon films

The influence of ion-plasma treatment of Cd$_{1-x}$Zn$_x$Te ($x\sim$0.04) single crystals, which precedes the deposition of an antireflection coating (a diamond-like $a$-C: H: N film) on the optical properties of the resulting structure, is investigated. Treatment is carried out in an argon, nitrogen, and hydrogen plasma. As follows from the optical properties of the $a$-C: H: N/Cd$_{1-x}$Zn$_x$Te, the structure treated in an argon plasma offers the highest transmission. A model of the optical system is proposed that takes into account the formation of transition layers after ion-plasma treatment and the effect of the type of ion on their characteristics. The absorption spectra of the $a$-C: H: N/Cd$_{1-x}$Zn$_x$Te system are analyzed, and bands assigned to the stretching and bending vibrations of C–H bonds, as well as to C–C and C = O bonds, are revealed. The presence of these bonds should be taken into account in designing and synthesizing these optical coatings.