The electrical properties and fermi level pinning in proton-irradiated GaSb

Fermi level pinning and hydrostatic pressure effect in electron irradiated GaSb

“…Upon the high doses of electron irradiation, all studied samples obtained a p-type conductivity with a hole concentration at about of 5 × 10 18 cm −3 that corresponds to the Fermi level position near the valence band top (VBT), at about E V + 0.03 eV. These results close to the previous studies of the proton and neutron-irradiated GaSb samples [14,15]. At the same time in the initial heavily doped p + -GaSb:Zn (p 0 = 1.29 × 10 19 cm −3 ) samples the concentration of the holes decreases after the proton irradiation which indicates the introduction of the donor-type defects [14].…”

On the electronic properties of GaSb irradiated with reactor neutrons and its charge neutrality level

“…As a result, the Fermi level is shifted from its initial position, defined by the level of doping with chemical impurities, towards the valence band of the compound and subse quently stabilized near the level Γ 8V . The average energy position of the level F lim estimated from exper imental data on the electronic properties of GaSb crystals irradiated with protons (E = 5 MeV, Φ = 1.7 × 10 16 cm -2 ) [1], electrons (E = 2 MeV, Φ = 1 × 10 19 cm -2 ) [2], and reactor neutrons (Φ = 8.6 × 10 18 cm -2 ) corre sponds to E V + (0.02 ± 0.01) eV, which is rather close to the averaged result of theoretical estimations of this parameter, E V + (0.01 ± 0.05) eV (see table).…”

“…2). CNL energy position estimated for GaSb from measurements of F lim [1,2], studies of interfaces [4][5][6], and calculations [7][8][9][10]. (The CNL position (eV) is reckoned from the top of the valence band)…”

“…Therefore, to produce GaSb material of the n type, it is necessary to carry out over compensation of the material with donor impurities during growth or to conduct the postgrowth diffusion of such impurities. Previously [1,2], it was shown that irradiation with electrons or protons transformed n GaSb into the p type material and, in lightly doped p GaSb, the concentration of free holes increased. Such features of GaSb are attributed to the predomi nant formation of acceptor type defects, supposedly Ga vacancies (V Ga ) and antisite defects typical of com positionally complex semiconductors, during growth of the material and upon exposure of the material to high energy radiation.…”

Robustness of ferromagnetism in (In,Fe)Sb diluted magnetic semiconductor to variation of charge carrier concentration

“…The creation of RDs in (Ga,Mn)As makes it possible to vary the carrier density and to analyze the carrier density influence on the transport and magnetic properties [10][11][12]. The consequence of RDs creation in the GaSb and InAs matrices is the appearance of additional charge carriers (holes in GaSb and electrons in InAs), which is accompanied by a Fermi level (E F ) shift into the valence or conduction band in GaSb [13] and InAs [14], respectively. In the InSb matrix the radiation defects manifest themselves in a more complex way -both acceptor and donor centers appear [15,16].…”