62 research outputs found
Highâtemperature behavior of impurities and dimensionality of the charge transport in unintentionally and tinâdoped indium selenide
A systematic study of the electron transport and shallow impurity distribution in indium selenide above room temperature or after an annealing process is reported by means of farâinfraredâabsorption and Hallâeffect measurements. Evidences are found for the existence of a large concentration of deep levels (1012â1013 cmâ2), related to impurities adsorbed to stacking faults in this material. Above room temperature impurities can migrate from those defect zones and then become shallow in the bulk. The subsequent large increase of 3D electrons can change the dimensionality of the electron transport, which in most cases was 2D. The temperature dependence of the resistivity parallel to the c axis can be explained by the observed increase of the 3D electron concentration, whose motion across the layers is limited by stackingâfaultârelated potential barriers. The observed macroscopic resistivity is thus determined by tunneling through those [email protected]
- âŚ