High pressure studies of electron mobility in heavily doped GaAs: fitting of the absolute value

Abstract
The mobility, mu , and the carrier concentration, n, of GaAs heavily doped with Si, Sn, and Te is measured at pressures up to 20 kbar and at temperatures from 4.2 to 295 K. The samples of GaAs:Si and GaAs:Sn exhibit strong changes of n and mu with pressure. For these samples a theoretical fit is presented to the absolute values of mu , including scattering mechanisms caused by spatially correlated charged donors, short-range potentials related to DX centres and compensating ionized acceptors. The suggestion that after applying pressure the main influence on mu behaviour originates from spatially correlated charged donors is confirmed. The energy position of the Te-related DX level appears to be much higher than that for Si- and Sn-related DX centres.