@misc{KittlerReicheSchwartzetal., author = {Kittler, Martin and Reiche, Manfred and Schwartz, Bernhard and {\"U}bensee, Hartmut and Kosina, Hans and Stanojevic, Zlatan and Baumgartner, Oskar and Ortlepp, Thomas}, title = {Transport of Charge Carriers along Dislocations in Si and Ge}, series = {Physica status solidi. A, Applications and materials science}, volume = {Volume 216}, journal = {Physica status solidi. A, Applications and materials science}, number = {17}, issn = {1862-6319}, doi = {10.10002/pssa.201900287}, pages = {7}, abstract = {Experimental observations and quantum mechanical device simulations point to different electronic properties of dislocations in silicon and germanium. The experimental data suggest a supermetallic behavior of the dislocations in Si and thus the high strain in the dislocation core is thought to cause the confinement of the charge carriers, which leads to the formation of a 1D electron gas along a dislocation (quantum wire). The resulting significant increase in the electron concentration corresponds to a marked increase in the drain current of metal-oxide-semiconductor field-effect transistor (MOSFET). The specific resistance of an individual dislocation in Ge is about nine orders of magnitude higher than for a dislocation in Si. The experimental measurements of the strain in dislocation cores in Ge are still missing. Based on the band structure data, the generation of a strain equivalent to that of the dislocation cores in Si appears to be very challenging because of the transition from an indirect into a direct semiconductor with about tenfold lower strain levels. The lower strain in the dislocation core in germanium may not support the carrier confinement as proposed for the dislocation core of silicon, and consequently 1D electron gases are not expected to form along the dislocations in Ge.}, language = {en} } @misc{TrushinVarlamovLoshachenkoetal., author = {Trushin, Maxim and Varlamov, A. and Loshachenko, A. and Vyvenko, Oleg F. and Kittler, Martin}, title = {Combined DLTS/MCTS investigations of deep electrical levels of regular dislocation networks in silicon}, series = {Journal of Physics: Conference Series}, volume = {1190}, journal = {Journal of Physics: Conference Series}, number = {1}, issn = {1742-6596}, doi = {10.1088/1742-6596/1190/1/012005}, pages = {10}, abstract = {Local electronic states of regular dislocation networks produced by n- and p-type silicon wafer bonding with different screw dislocation density were studied with deep-level transient spectroscopy (DLTS) and minority carrier transient spectroscopy (MCTS). A drastic sadden changes of the electric level spectrum with increasing of dislocation density from two shallow bands located near the edges of valence and conduction bands towards two deep bands with energy positions about Ec - (0.22-0.26) eV and Ev + (0.4-0.53) eV were found. The origin of the electric level spectrum changes is ascribed to the changes of dislocation core structure from dissociated to perfect ones that occur when interdislocation distances became comparable with the dislocation equilibrium dissociation width. The obtained results correlate well with the results of recent studies of recombination activity of grain boundaries in mc-Si.}, language = {en} }