Electrical characterization of a He ion implantation-induced deep level existing in p+n InP junctions

Abstract

Combined optical and electrical studies of the effects of annealing on the intrinsic states and deep levels in a self-assembled InAs quantum-dot structure

Electrical characterization of He-ion implantation-induced deep levels in p+n InP junctions

“…9͒ eV for samples irradiated with O, all of them below the conduction band. For He irradiations, some authors 1,7 postulated the existence of both donor and acceptor deep levels associated with the He implantation for doses above 5ϫ10 13 cm Ϫ2 and we have experimentally verified this proposal in a recent communication. 13 In particular, we detected by deep-level transient spectroscopy ͑DLTS͒ an electron trap induced by He-ion implantation and its emission properties were investigated.…”

“…For He irradiations, some authors 1,7 postulated the existence of both donor and acceptor deep levels associated with the He implantation for doses above 5ϫ10 13 cm Ϫ2 and we have experimentally verified this proposal in a recent communication. 13 In particular, we detected by deep-level transient spectroscopy ͑DLTS͒ an electron trap induced by He-ion implantation and its emission properties were investigated. In every case, the above-mentioned traps determine the electrical properties of the investigated samples and, as they are not in the middle of the band gap, the relatively low values of resistivity obtainable by implantation in both nand p-type InP can be justified.…”

“…In particular, the technological origin of the E8 trap was associated with the He-ion bombardment. 13 Two important characteristics of the E8 trap emission process were also proved experimentally. First, its emission transients were purely exponential, and second, no dependence of the emission rate on electric field was found.…”

“…In previous works, 13,16,17 we have studied in detail the emission properties of the three electron traps ͑E6-, E7-, and E8-labeled deep levels͒ detected by majority DLTS measurements in the He-ion implantation-isolated samples. Yet, the existence of minority ͑hole͒ traps was not investigated.…”

“…We have already characterized the emission transients of the E8 level in a previous work. 13 In Fig. 2, two normalized capacitance transients of the H2 deep level at a fixed temperature obtained under different bias conditions are shown.…”