KINETICS OF MINORITY-CARRIER-ENHANCED DISSOCIATION OF HYDROGEN-DOPANT COMPLEXES IN SEMICONDUCTORS

The kinetics of minority-carrier-enhanced dissociation of dopant-hydrogen complexes in semiconductors are quantitatively characterized with a new experimental technique. Its principal feature is the ability to control independently the width of the space-charge layer and the flux of minority carriers through the layer. The dissociation kinetics are formulated in terms of a phenomenological cross section for the capture of a minority carrier by a dopant-hydrogen complex. The method is demonstrated with hole-enhanced dissociation of the PH complex in silicon. The capture cross section has a room-temperature value of approximately 3 X 10(-19) cm2 and is thermally activated with an energy of approximately 0.3 eV, as compared to the thermal dissociation energy of 1.2 eV for the PH complex. Possible mechanisms for minority-carrier-enhanced dissociation are evaluated with configuration coordinate diagrams.