APPLICATION OF EPITAXIAL COSI2 SI/COSI2 HETEROSTRUCTURES TO TUNABLE SCHOTTKY-BARRIER DETECTORS/

Epitaxial CoSi2/Si/CoSi2 heterostructures on Si(111) have been grown b y MBE. STM measurements during the growth process showed silicide laye rs below approximately 45 angstrom to be coherent apart from dislocati ons associated with the wafer misorientation, and the approximately 10 00 angstrom thick Si spacer to be pinhole-free. Diode structures were fabricated by standard photolithography and a combination of wet chemi cal and plasma etching. Both the upper and the buried silicide film co uld be contacted separately for electrical measurements. Vertical tran sport measurements showed blocking behaviour confirming the Si spacer layers to be continuous. The photoresponse of the diode structures was measured as a function of bias at 77 K. A maximum shift of the cutoff energy of 0.1 eV was obtained at an electrical field of 200 kV cm-1.