| Title |
Low Resistance Indium-based Ohmic Contacts to N-face n-GaN for GaN-based Vertical Light Emitting Diodes |
| Authors |
강기만(Ki Man Kang); 박민주(Min Joo Park); 곽준섭(Joon Seop Kwak); 김현수(Hyun Soo Kim); 권광우(Kwang Woo Kwon); 김영호(Young Ho Kim) |
| DOI |
https://doi.org/10.3365/KJMM.2010.48.05.456 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
semiconductors; sputtering; electrical properties electrical |
| Abstract |
We investigated the In-based ohmic contacts on Nitrogen-face (N-face) n-type GaN, as well as Gaface n-type GaN, for InGaN-based vertical Light Emitting Diodes (LEDs). For this purpose, we fabricated Circular Transfer Length Method (CTLM) patterns on the N-face n-GaN that were prepared by using a laserlift off method, as well as on the Ga-face n-GaN that were prepared by using a dry etching method. Then, In/transparent conducting oxide (TCO) and In/TiW schemes were deposited on the CTLM in order for low resistance ohmic contacts to form. The In/TCO scheme on the Ga-face n-GaN showed high specific contact resistance, while the minimum specific contact resistance was only 3×10(-2) Ω-cm2 after annealing at 300℃, which can be attributed to the high sheet resistance of the TCO layer. In contrast, the In/TiW scheme on the Ga-face n-GaN produced low specific contact resistance of 2.1×10(5) Ω-cm2 after annealing at 500℃ for 1 min. In addition, the In/TiW scheme on the N-face n-GaN also resulted in a low specific contact resistance of 2.2×10(-4) Ω-cm2 after annealing at 300℃. These results suggest that both the Ga-face n-GaN and N-face n-GaN. |