  We show that spin polarization of electrons in nonmagnetic semiconductors
near specially tailored ferromagnet-semiconductor junctions can achieve 100%.
This effect is realized even at moderate spin injection coefficients of the
contact when these coefficients only weakly depend on the current. The effect
of complete spin extraction occurs at relatively strong electric fields and
arises from a reduction of spin penetration length due to the drift of
electrons from a semiconductor towards the spin-selective tunnel junction.
