MINORITY CARRIER INJECTION OF METAL-SILICON CONTACTS

The minority carrier injection ratio from metal-silicon contacts has been measured using a metal-emitter transistor structure. Contacts of four different metals with barrier heights ranging from 0.65 to 0.85 eV on n-type silicon with doping level from 1014 to 6 × 1016 cm-3 were examined. This systematic investigation shows that the injection ratio at low current levels is a constant and is determined only by the barrier height of the contact and the doping of the semiconductor, while at high currents it increases with the total current. This result is in good agreement with theoretical predictions. © 1969.