Low-temperature conduction in germanium with disorder caused by extended defects

Abstract

Investigalhs were carried out on low-femperaw conductivity in the defect band of germanium formed due to the presence of large concenkations of exfended defects introduced during high-temperature plastic deformation or irradiation with large imgnted fluxes of highenergy neutmns and pmtons. It has been demonshared iim at relatively low concentrations of dislocations and low t e m p " the electrical conductivity in the defect band DECW by hopping. At higher concentrations of dislocations the metalinsolator transition (m) tsLes place in Ihe system of dislogtions, the conductivity ma^ the m showing a power-law v;uiatioh o(T) * T", with x =S 1 in the range 30 to 3 x 1W2 K It has also been shown that the dislocation conductivity has a quasi-two-dimensional charscter. The dynamics of the Coulomb gap variations was Studied near the m in Ge with a high concenh'aIion of radiation defects.The experimental data presenled show that Ge with a high concentration of dislocations can be used for simulating Some physical phenomena in amorphous and viaous semiconductors.

Electrical isolation of dislocations in Ge layers on Si(001) substrates through CMOS-compatible suspended structures

“…Within this low-temperature regime, below 20 K, the resistivity of the suspended Ge plateaus is increased from 2.5 cm on the bulk sample by over two orders of magnitude to a maximum of 280 cm in the suspended structure. Compared to a similar study in bulk Ge with induced dislocations by Hung and Gliessman and by Kozhukh [40,41], these values suggest that our Ge layer is exhibiting the typical conduction and general trends with temperature observed when transport is dominated by impurities at a level of about 10 16 cm −3 .…”

Electrical Isolation of Dislocations in Ge Layers on Si(001) Substrates through CMOS Compatible Suspended Structures

“…Within this low temperature regime the resistivity of the suspended Ge plateaus below 20°K and is increased from 2.5 FP on the bulk sample by over two orders of magnitude to a maximum in the suspended structure of 280 FP. Compared to a similar study in bulk Ge with induced dislocations by Hung et al and by Kozhukh (38,39), these values suggest that our Ge layer is showing typical conduction dominated by impurities at a level of about 10 16 cm -3 and exhibiting similar general trends with temperature.…”

“…Within this low-temperature regime, below 20 K, the resistivity of the suspended Ge plateaus is increased from 2.5 cm on the bulk sample by over two orders of magnitude to a maximum of 280 cm in the suspended structure. Compared to a similar study in bulk Ge with induced dislocations by Hung and Gliessman and by Kozhukh [40,41], these values suggest that our Ge layer is exhibiting the typical conduction and general trends with temperature observed when transport is dominated by impurities at a level of about 10 16 cm −3 . These observations are supported by Hall measurements in a field of 600 mT, which produce the results shown in figure 7(c).…”

Gamma-ray focusing telescope based on high reflective Ge and Si mosaic crystals

“…This technique was successfully employed for fabrication of both thick Ge mosaic crystals and thin Ge wafers for neutron monochromators [12,13]. Although the technique provides a wide range of mosaicity for Ge crystals/wafers, the rocking curve peak slow neutron reflectivity is not very high.…”

“…x Si x solid solution mosaic crystals [8][9][10][11][12]. Grown by special technology 1.4-cm diameter Ge 1-x Si x crystals (x 15 atomic %) with mosaicity of 10 arc minutes had reflectivity of 85% for the = 1.5 Å neutrons (the highest reflectivity ever achieved for mosaic crystals).…”