### Thermal Stability of Nitride-Based Diffusion Barriers for Ohmic Contacts to n-GaNThermal Stability of Nitride-Based Diffusion Barriers for Ohmic Contacts to n-GaN

Access Restriction
Subscribed

 Author Voss, L.F. ♦ Stafford, L. ♦ Khanna, R. ♦ Gila, B.P. ♦ Abernathy, C.R. ♦ Pearton, S.J. ♦ Ren, F. ♦ Kravchenko, I.I. Source SpringerLink Content type Text Publisher Springer US File Format PDF Copyright Year ©2007 Language English
 Subject Domain (in DDC) Natural sciences & mathematics ♦ Chemistry & allied sciences Subject Keyword GaN ♦ Ohmic contacts ♦ Solid State Physics and Spectroscopy ♦ Electronics and Microelectronics, Instrumentation ♦ Characterization and Evaluation of Materials ♦ Optical and Electronic Materials Abstract The use of TaN, TiN, and ZrN diffusion barriers for Ti/Al-based contacts on n-GaN (n ∼ 3 × 10$^{17}$ cm$^{−3}$) is reported. The annealing temperature (600–1,000°C) dependence of the Ohmic contact characteristics using a Ti/Al/X/Ti/Au metallization scheme, where X is TaN, TiN, or ZrN, deposited by sputtering was investigated by contact resistance measurements and Auger electron spectroscopy (AES). The as-deposited contacts were rectifying and transitioned to Ohmic behavior for annealing at ≥600°C. A minimum specific contact resistivity of ∼6 × 10$^{−5}$ Ω-cm$^{−2}$ was obtained after annealing over a broad range of temperatures (600–900°C for 60 s), comparable to that achieved using a conventional Ti/Al/Pt/Au scheme on the same samples. The contact morphology became considerably rougher at the high end of the annealing range. The long-term reliability of the contacts at 350°C was examined; each contact structure showed an increase in contact resistance by a factor of three to four over 24 days at 350°C in air. AES profiling showed that the aging had little effect on the contact structure of the nitride stacks. ISSN 03615235 Age Range 18 to 22 years ♦ above 22 year Educational Use Research Education Level UG and PG Learning Resource Type Article Publisher Date 2007-09-21 Publisher Place Boston e-ISSN 1543186X Journal Journal of Electronic Materials Volume Number 36 Issue Number 12 Page Count 7 Starting Page 1662 Ending Page 1668

#### Open content in new tab

Source: SpringerLink