Abstract
We studied the effect of Bi incorporation on the hole mobility in the dilute bismide alloy GaAsBi using electrical transport (Hall) and photoluminescence (PL) techniques. Our measurements show that the hole mobility decreases with increasing Bi concentration. Analysis of the temperature-dependent Hall transport data of -type GaAsBi epilayers along with low-temperature PL measurements of -doped and undoped epilayers suggests that Bi incorporation results in the formation of several trap levels above the valence band, which we attribute to Bi-Bi pair states. The decrease in hole mobility with increasing Bi concentration can be explained as being caused by scattering at the isolated Bi and the Bi-Bi pair states. We also observed a decrease in hole concentration with Bi incorporation. We believe that Bi heteroantisite defects compensate the acceptors, thus reducing the effective hole concentration.
- Received 12 August 2010
DOI:https://doi.org/10.1103/PhysRevB.83.075307
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