-
The specific contact resistivity and reflectivity of Ni/Ag/Ti/Au contact with p-GaN are studied. It is found that the thickness of Ag, anneal time and deposition temperature have a great effect on the performance of Ni/Ag/Ti/Au electrode. Its optical reflectivity is measured by reflectivity spectrophotometer, and its specific contact resistivity is calculated by circular transmission line model. It is observed that the contact reflectivity values of Ni (1 nm)/Ag/Ti (100 nm)/Au (100 nm), when the thickness values of Ag are 25 nm and 50 nm, are low: their values are 68.5% and 82.1% at 450 nm, respectively, and they start to increase with increasing the Ag thickness, then reach their saturated values when Ag thickness is beyond 200 nm. When the anneal time changes from 1 min to 10 min in oxygen atmosphere, the specific contact resistivity decreases at 300 ℃, decreases further and then increases at 400-600 ℃. After annealing at temperatures at 300 ℃ and 400 ℃ in oxygen atmosphere, the contact reflectivity value of Ni/Ag/Ti/Au remains almost unchanged, even when anneal time increases from 1 min to 10 min. However, The contact reflectivity of Ni/Ag/Ti/Au decreases significantly after annealing at a temperature higher than 400 ℃ and it becomes smaller with longer annealing time. After 400 ℃ annealing in oxygen atmosphere for 3 min, the specific contact resistivity reaches 3.6×10-3 Ω·cm2. Additionally, the deposition temperature of Ni/Ag is investigated. It is noticed that the specific contact resistivity decreases and the reflectivity increases with increasing the deposition temperature from room temperature to 120 ℃. The reflectivity rises to 90.1% at 450 nm and the specific contact resistivity reaches 6.4×10-3Ω·cm2 for the Ni/Ag/Ti/Au electrode at a deposition temperature of 120 ℃. However, the effects of improving the electrical and optical characteristics weaken when deposition temperature changes from 120 ℃ to 140 ℃. With a overall consideration, Ni (1 nm)/Ag (200 nm)/Ti (100 nm)/Au (100 nm) is made at a deposition temperature of 120 ℃, and then anneals at 400 ℃ for 3 min in oxygen atmosphere to achieve the optimized electrode. The vertical light emitting diode with this Ni/Ag/Ti/Au electrode is fabricated. Its working voltage is 2.95 V and the light output power is 387.1 mW at 350 mA. The electro-optical conversion efficiency reaches 37.5%.
-
Keywords:
- p-GaN /
- ohmic contact /
- reflectivity
[1] Greco G, Prystawko P, Leszczynski M, Nigro R L, Raineri V, Roccaforte F 2011 J. Appl. Phys. 110 123703
[2] Lin D W, Lee C Y, Liu C Y, Han H V, Lan Y P, Lin C C, Chi G C, Kuo H C 2012 Appl. Phys. Lett. 101 233104
[3] Xiong J Y, Zhao F, Fan G H, Xu Y Q, Liu X P, Song J J, Ding B B, Zhang T, Zheng S W 2013 Chin. Phys. B 22 118504
[4] Yang B, Guo Z Y, Xie N, Zhang P J, Li J, Li F Z, Lin H, Zheng H, Cai J X 2014 Chin. Phys. B 23 048502
[5] Kim H, Kim K K, Choi K K, Kim H, Song J O, Cho J, Baik K H, Sone C, Park Y, Seong T Y 2007 Appl. Phys. Lett. 91 023510
[6] Jeon J W, Seong T Y, Kim H, Kim K K 2009 Appl. Phys. Lett. 94 042102
[7] Feng F F, Liu J L, Qiu C, Wang G X, Jiang F Y 2010 Acta Phys. Sin. 59 5706 (in Chinese) [封飞飞, 刘军林, 邱冲, 王光绪, 江风益 2010 物理学报 59 5706]
[8] Liu J L, Feng F F, Zhou Y H, Zhang J L, Jiang F Y 2011 Appl. Phys. Lett. 99 111112
[9] Magdenko L, Patriarche G, Troadec D, Mauguin O, Morvan E, di Forte-Poisson M A, Pantzas K, Ougazzaden A, Martinez A, Ramdane A 2012 J. Vac. Sci. Technol. B 30 022205
[10] Guo D B, Liang M, Fan M N, Shi H W, Liu Z Q, Wang G H, Wang L C 2007 Chin. J. Semiconductors 28 1811 (in Chinese) [郭德博, 梁萌, 范曼宁, 师宏伟, 刘志强, 王国宏, 王良臣 2007 半导体学报 28 1811]
[11] Jeon J W, Yum W S, Oh S, Kim K K, Seong T Y 2012 Appl. Phys. Lett. 101 021115
[12] Huang Y P, Yun F, Ding W, Wang Y, Wang H, Zhao Y K, Zhang Y, Guo M F, Hou X, Liu S 2014 Acta Phys. Sin. 63 127302 (in Chinese) [黄亚平, 云峰, 丁文, 王越, 王宏, 赵宇坤, 张烨, 郭茂峰, 侯洵, 刘硕 2014 物理学报 63 127302]
[13] Julita S K, Szymon G, Elzbieta L S, Ryszard P, Grzegorz N, Michal L, Piotr P, Ewa T, Jan K, Stanislaw K 2010 Solid State Electron. 54 701
[14] Qiao D, Yu L S, Lau S S, Lin J Y, Jiang H X, Haynes T E 2000 J. Appl. Phys. 88 4196
[15] Chary I, Chandolu A, Borisov B, Kuryatkov V, Nikishin S, Holtz M 2009 J. Electron. Mater. 38 545
[16] Jiang F, Cai L E, Zhang J Y, Zhang B P 2010 Physica E 42 2420
[17] Jang H W, Lee J L 2004 Appl. Phys. Lett. 85 5920
[18] Tian T, Wang L C, Guo E Q, Liu Z Q, Zhan T, Guo J X, Yi X Y, Li J, Wang G H 2014 J. Phys. D: Appl. Phys. 47 115102
[19] Mashaiekhy J, Shafieizadeh Z, Nahidi H 2012 Eur. Phys. J. Appl. Phys. 60 20301
[20] Song Y H, Son J H, Yu H K, Lee J H, Jung G H, Lee J Y, Lee J L 2011 Cryst. Growth Des. 11 2559
[21] Kim S, Jang J H, Lee J S 2007 J. Electrochem. Soc. 154 973
[22] Son J H, Yu H K, Song Y H, Kim B J, Lee J L 2011 Cryst. Growth Des. 11 4943
[23] Chou C H, Lin C L, Chuang Y C, Bor H Y, Liu C Y 2007 Appl. Phys. Lett. 90 022103
-
[1] Greco G, Prystawko P, Leszczynski M, Nigro R L, Raineri V, Roccaforte F 2011 J. Appl. Phys. 110 123703
[2] Lin D W, Lee C Y, Liu C Y, Han H V, Lan Y P, Lin C C, Chi G C, Kuo H C 2012 Appl. Phys. Lett. 101 233104
[3] Xiong J Y, Zhao F, Fan G H, Xu Y Q, Liu X P, Song J J, Ding B B, Zhang T, Zheng S W 2013 Chin. Phys. B 22 118504
[4] Yang B, Guo Z Y, Xie N, Zhang P J, Li J, Li F Z, Lin H, Zheng H, Cai J X 2014 Chin. Phys. B 23 048502
[5] Kim H, Kim K K, Choi K K, Kim H, Song J O, Cho J, Baik K H, Sone C, Park Y, Seong T Y 2007 Appl. Phys. Lett. 91 023510
[6] Jeon J W, Seong T Y, Kim H, Kim K K 2009 Appl. Phys. Lett. 94 042102
[7] Feng F F, Liu J L, Qiu C, Wang G X, Jiang F Y 2010 Acta Phys. Sin. 59 5706 (in Chinese) [封飞飞, 刘军林, 邱冲, 王光绪, 江风益 2010 物理学报 59 5706]
[8] Liu J L, Feng F F, Zhou Y H, Zhang J L, Jiang F Y 2011 Appl. Phys. Lett. 99 111112
[9] Magdenko L, Patriarche G, Troadec D, Mauguin O, Morvan E, di Forte-Poisson M A, Pantzas K, Ougazzaden A, Martinez A, Ramdane A 2012 J. Vac. Sci. Technol. B 30 022205
[10] Guo D B, Liang M, Fan M N, Shi H W, Liu Z Q, Wang G H, Wang L C 2007 Chin. J. Semiconductors 28 1811 (in Chinese) [郭德博, 梁萌, 范曼宁, 师宏伟, 刘志强, 王国宏, 王良臣 2007 半导体学报 28 1811]
[11] Jeon J W, Yum W S, Oh S, Kim K K, Seong T Y 2012 Appl. Phys. Lett. 101 021115
[12] Huang Y P, Yun F, Ding W, Wang Y, Wang H, Zhao Y K, Zhang Y, Guo M F, Hou X, Liu S 2014 Acta Phys. Sin. 63 127302 (in Chinese) [黄亚平, 云峰, 丁文, 王越, 王宏, 赵宇坤, 张烨, 郭茂峰, 侯洵, 刘硕 2014 物理学报 63 127302]
[13] Julita S K, Szymon G, Elzbieta L S, Ryszard P, Grzegorz N, Michal L, Piotr P, Ewa T, Jan K, Stanislaw K 2010 Solid State Electron. 54 701
[14] Qiao D, Yu L S, Lau S S, Lin J Y, Jiang H X, Haynes T E 2000 J. Appl. Phys. 88 4196
[15] Chary I, Chandolu A, Borisov B, Kuryatkov V, Nikishin S, Holtz M 2009 J. Electron. Mater. 38 545
[16] Jiang F, Cai L E, Zhang J Y, Zhang B P 2010 Physica E 42 2420
[17] Jang H W, Lee J L 2004 Appl. Phys. Lett. 85 5920
[18] Tian T, Wang L C, Guo E Q, Liu Z Q, Zhan T, Guo J X, Yi X Y, Li J, Wang G H 2014 J. Phys. D: Appl. Phys. 47 115102
[19] Mashaiekhy J, Shafieizadeh Z, Nahidi H 2012 Eur. Phys. J. Appl. Phys. 60 20301
[20] Song Y H, Son J H, Yu H K, Lee J H, Jung G H, Lee J Y, Lee J L 2011 Cryst. Growth Des. 11 2559
[21] Kim S, Jang J H, Lee J S 2007 J. Electrochem. Soc. 154 973
[22] Son J H, Yu H K, Song Y H, Kim B J, Lee J L 2011 Cryst. Growth Des. 11 4943
[23] Chou C H, Lin C L, Chuang Y C, Bor H Y, Liu C Y 2007 Appl. Phys. Lett. 90 022103
Catalog
Metrics
- Abstract views: 5448
- PDF Downloads: 212
- Cited By: 0