A COMPLETE CHARACTERIZATION OF TRAPPING LEVELS IN RED MERCURIC IODIDESINGLE-CRYSTALS

Photon stimulated current measurements have been performed on red merc uric iodide single crystals in order to determine the trap energy, tra p density, and capture cross section for different trapping levels tha t may be present in the platelet-shaped single crystals of red mercuri c iodide grown by polymer controlled growth technique in vapor phase. The procedure of analysis of these measurements is outlined in brief. The analysis has shown that these crystals in general possess four tra pping levels: two electron trapping levels with energies 0.10 and 0.31 eV and two hole trapping levels with energies 0.15 and 0.59 eV. The a nalysis has further shown that the total trap density is only of the o rder of 10(13)/cm3, indicating the superiority of this growth techniqu e over other techniques. The analysis has also shown that all four tra pping levels are of retrapping type. Finally, the possible mechanisms of formation of these trapping levels and the ways in which these trap ping levels will influence the detector operation at room temperature are discussed.