Influence of thermally annealed Schottky metal contact on DC and RF behavior of n-GaN Schottky diode

摘要

In this paper we discuss the influence of thermally annealed Schottky metal contact on DC and RF characteristics of n-GaN Schottky diode. The fabrication of n-GaN Schottky diode started with mesa mask RIE etching and then lift off Al as an ohmic contact annealed at 400°C in N_2 ambient for 10 min. For Schottky contact lift off Pt, Ni and Pd Schottky metal annealed from 400°C to 600°C for 10 min. DC analysis shows that thermally annealed Pt schottky metal contact on n-GaN at 400°C improved the (I-V) characteristics maximum barrier height (Φ_B) 1.10 eV, ideality factor (η) 1.001 and high breakdown voltage with low leakage current as compared to the Pd and Ni Schottky metal contact. While for RF analysis, s-parameters were calculated up to 10GHz by using two-port network. Results show that thermally annealed Pt Schottky metal contact shows lower insertion losses as compared to Pd and Ni Schottky metal contact.