Low resistance and transparent Ni–La solid solution/Au ohmic contacts to p-type GaN

June-O Song, H.L.; Dong-Seok Leem; Kwak, J.S.; Lee, S.N.; Nam, O.H.; Park, Y.; Tae-Yeon Seong
March 2004
Applied Physics Letters;3/1/2004, Vol. 84 Issue 9, p1504
Academic Journal
We report on the formation of reliable Ni–La solid solution (8 nm)/Au (8 nm) ohmic contacts to p-type GaN (N[sub a]=5×10[sup 17] cm[sup -3]). The as-deposited contact reveals nonlinear current–voltage (I–V) characteristics. However, the contacts show considerably improved I–V behavior when annealed at temperatures of 350–550 °C for 1 min in air ambient. For example, the specific contact resistance as low as 7.2×10[sup -5] Ω cm[sup 2] is obtained from the samples annealed at 550 °C, whose transmittance is measured to be 82.5% at a wavelength of 470 nm. Based on Auger electron spectroscopy and x-ray photoemission spectroscopy results, possible ohmic formation mechanisms for the annealed contacts are described and discussed. © 2004 American Institute of Physics.


Related Articles

  • Low resistance ohmic contacts on wide band-gap GaN. Lin, M.E.; Ma, Z. // Applied Physics Letters;2/21/1994, Vol. 64 Issue 8, p1003 

    Examines the metal contacts on gallium nitride using titanium, aluminum and gold. Application of the metallization process for low resistance ohmic contacts; Deposition of the metals via electron-beam evaporation; Investigation of the metallurgy of contact formation by Auger electron spectroscopy.

  • Electrical properties of sputtered-indium tin oxide film contacts on n-type GaN. Hwang, J. D.; Lin, C. C.; Chen, W. L. // Journal of Applied Physics;8/15/2006, Vol. 100 Issue 4, p044908 

    A transparent indium tin oxide (ITO) Ohmic contact on n-type gallium nitride (GaN) (dopant concentration of 2×1017 cm-3) having a specific contact resistance of 4.2×10-6 Ω cm2 was obtained. In this study, ITO film deposition method was implemented by sputtering. We found that the...

  • Effects of sulfur passivation on Ti/Al ohmic contacts to n-type GaN using CH[sub 3]CSNH[sub 2] solution. Song, June O; Park, Seong-Ju; Seong, Tae-Yeon // Applied Physics Letters;4/29/2002, Vol. 80 Issue 17, p3129 

    We investigate the effect of CH[sub 3]CSNH[sub 2] solution treatment on Ti/Al ohmic contacts to n-GaN:Si (3×10[sup 18] cm[sup -3]). It is shown that the sulfide treatment results in a drastic increase in the photoluminescence intensity, compared with that of the untreated sample....

  • Low resistance Ti/Pt/Au ohmic contacts to p-type GaN. Zhou, L.; Lanford, W.; Ping, A. T.; Ping, A.T.; Adesida, I.; Yang, J. W.; Yang, J.W.; Khan, A. // Applied Physics Letters;6/5/2000, Vol. 76 Issue 23 

    Electrical properties of Ti (15 nm)/Pt (50 nm)/Au (80 nm) contacts on moderately doped p-GaN (N[sub A]=3.0x10[sup 17] cm[sup -3]) are reported. Linear current-voltage characteristics were observed after annealing the contacts for 1 min at temperatures above 700 °C. The best ohmic contacts...

  • Electronic transport mechanisms of nonalloyed Pt Ohmic contacts to p-GaN. Jang, Ja-Soon; Ja-Soon Jang; Seong, Tae-Yeon; Tae-Yeon Seong // Applied Physics Letters;5/8/2000, Vol. 76 Issue 19 

    We report on the electronic transport mechanisms for nonalloyed Pt Ohmic contacts to p-GaN which were surface treated using a buffered oxide etch solution and (NH[sub 4])[sub 2]S[sub x]. Measurements show that the value of the effective Richardson constant (A[sup **]) is 12 A cm-2 K-2, which is...

  • Low-resistance ohmic contacts to p-type GaN. Li, Y.-L.; Schubert, E. F.; Schubert, E.F.; Graff, J. W.; Graff, J.W.; Osinsky, A.; Schaff, W. F.; Schaff, W.F. // Applied Physics Letters;5/8/2000, Vol. 76 Issue 19 

    The specific contact resistance of two types of ohmic contacts to p-type GaN is analyzed. First, an ohmic contact formed by a metal electrode deposited on a highly doped p-type GaN layer. Second, an ohmic contact formed by a metal electrode deposited on a thin GaN layer with an internal electric...

  • Investigation of surface treatments for nonalloyed ohmic contact formation in Ti/Al contacts to n-type GaN. Lin, Yow-Jon; Yow-Jon Lin; Lee, Ching-Ting; Ching-Tee Lee // Applied Physics Letters;12/11/2000, Vol. 77 Issue 24 

    To investigate the possibility of preparing a nonalloyed ohmic contact to n-type GaN, the effects of GaN surface treatments on the metal/GaN interface were studied using x-ray photoelectron spectroscopy. A specific contact resistance of 5.0x10[sup -5] Ω cm[sup 2] for the Ti/Al nonalloyed...

  • Effect of alcohol-based sulfur treatment on Pt Ohmic contacts to p-type GaN. Huh, Chul; Kim, Sang-Woo; Kim, Hyun-Min; Kim, Dong-Joon; Park, Seong-Ju // Applied Physics Letters;3/26/2001, Vol. 78 Issue 13, p1942 

    The effects of an alcohol-based (NH[sub 4])[sub 2]S solution [t-C[sub 4]H[sub 9]OH+(NH[sub 4])[sub 2]S] treatment on Pt Ohmic contacts to p-type GaN are presented. The specific contact resistance decreased by three orders of magnitude from 2.56x10[sup -2] to 4.71x10[sup -5] Ω cm[sup 2] as a...

  • Room-temperature Ohmic contact on n-type GaN with surface treatment using Cl[sub 2] inductively coupled plasma. Jang, Ho Won; Jeon, Chang Min; Kim, Jong Kyu; Lee, Jong-Lam // Applied Physics Letters;4/2/2001, Vol. 78 Issue 14, p2015 

    A room-temperature Ti/Al Ohmic contact on n-type GaN was obtained by surface treatment using Cl[sub 2] inductively coupled plasma treatment. The specific contact resistivity was dramatically decreased from the Schottky behavior to 9.4x10[sup -6] Ω cm[sup 2] by the treatment. The binding...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics