Persistent galvanomagnetic effects related to photo-quenching phenomena in lightly n-type LEC GaAs


Yildirim M., Tuzemen S., Gurbulak B., Ates A., Ayyildiz E.

PHYSICA SCRIPTA, cilt.63, ss.169-172, 2001 (SCI İndekslerine Giren Dergi) identifier identifier

Özet

We investigated the effect of photo quenching on the galvanomagnetic properties in Te doped n-type GaAs grown by Liquid Encapsulated Czochralski (LEC) process. Although magnetoresistance coefficient and carrier concentration do not change as a function of photo-quenching time at 55 K, the Hall mobility increases with increasing photoquenching illumination time. This results from the photo-quenching of the EL2 centres. On the other hand, the Hall mobility and carrier concentration increase with increasing photoquenching time at 10 K. These are expected because of the acceptor behaviour of reverse contrast (RC) centres. The magnetoresistance coefficients are constant at this temperature. Two different kinds of photo-quenching are once again observed in lightly n-type GaAs at sample temperature of below 65 K and 40 K from a different aspect using galvano-magnetic effects.