SCHOTTY DIODE TYPE PH SENSOR UTILIZING UNDOPED ALGAN/GAN HEMT STRUCTURE

摘要

A pH SENSOR DEVICE (10) COMPRISES OF A SUBSTRATE (11), A BUFFER LAYER (12) FORMED ON SAID SUBSTRATE (11), AN UNDOPED GALLIUM NITRIDE (GaN) LAYER (13) FORMED ON SAID BUFFER LAYER (12), AND AN UNDOPED ALUMINIUM GALLIUM NITRIDE (A1GaN) LAYER (14) FORMED ON SAID UNDOPED GaN LAYER (13), WHEREIN SAID UNDOPED A1GaN LAYER HAVING A MULTI-LAYER RING OHMIC CONTACT (15) AND A CIRCULAR Pd OR Pt OR CALOMEL SCHOTTKY CONTACT (16) FABRICATED THEREON, SAID MULTI-LAYER RING OHMIC CONTACT (15) IS COVERED WITH A LAYER OF SiO2 OR Si3Nx FILM (17). MOST ILLUSTRATIVE DRAWINGS: FIG. 2