INTERFACE PROPERTIES OF PNX INP STRUCTURES BY IN-SITU REMOTE PLASMA PROCESSES/

Interfacial properties of Au/PNx/n-InP Schottky junctions and metal-in sulator-semiconductor (MIS) diodes formed by a series of in-situ remot e plasma processes have been evaluated by measuring electrical charact eristics. The in-situ processes consist of removal of native oxide by a H-2 plasma, surface modification by a PH3 plasma, deposition of a PN x layer by the use of PH3 and N-2 plasma, and subsequent metal evapora tion. An effective barrier height of 0.83 eV and a true barrier height of 0.57 eV are observed for the tunnel MIS Schottky junction. An inte rface state density as low as 1.4 x 10(11) eV(-1) cm(-2) is obtained f or the MIS diodes. From the behavior of the true barrier height and th e low interface state density, it is suggested that a novel in-situ pr ocess is effective in forming an interface of PNx/InP structure.