Effects of hole-injection through side-walls of large V-pits on efficiency droop in Ⅲ–nitride LEDs
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摘要
Although the solid-state lighting market is growing rapidly, it is still difficult to obtain ultra-high brightness white light emitting diodes(LEDs). V-pits are inevitably introduced during the metalorganic chemical vapor deposition(MOCVD)growth of multiple quantum wells(MQWs) in Ⅲ–nitride LEDs, and thus affecting the carrier dynamics of the LEDs.Specifically designed structures are fabricated to study the influence of the V-pits on the hole transportation and efficiency droop, and double quantum wells(QWs) are used to monitor the transportation and distribution of holes based on their emission intensity. It is found that when compared with the planar QWs, the injection of holes into the QWs through the side walls of the V-pits changes the distribution of holes among the MQWs. This results in a higher probability of hole injection into the middle QWs and enhanced emission therein, and, consequently, a lower efficiency droop.
Although the solid-state lighting market is growing rapidly, it is still difficult to obtain ultra-high brightness white light emitting diodes(LEDs). V-pits are inevitably introduced during the metalorganic chemical vapor deposition(MOCVD)growth of multiple quantum wells(MQWs) in Ⅲ–nitride LEDs, and thus affecting the carrier dynamics of the LEDs.Specifically designed structures are fabricated to study the influence of the V-pits on the hole transportation and efficiency droop, and double quantum wells(QWs) are used to monitor the transportation and distribution of holes based on their emission intensity. It is found that when compared with the planar QWs, the injection of holes into the QWs through the side walls of the V-pits changes the distribution of holes among the MQWs. This results in a higher probability of hole injection into the middle QWs and enhanced emission therein, and, consequently, a lower efficiency droop.
Although the solid-state lighting market is growing rapidly, it is still difficult to obtain ultra-high brightness white light emitting diodes(LEDs). V-pits are inevitably introduced during the metalorganic chemical vapor deposition(MOCVD)growth of multiple quantum wells(MQWs) in Ⅲ–nitride LEDs, and thus affecting the carrier dynamics of the LEDs.Specifically designed structures are fabricated to study the influence of the V-pits on the hole transportation and efficiency droop, and double quantum wells(QWs) are used to monitor the transportation and distribution of holes based on their emission intensity. It is found that when compared with the planar QWs, the injection of holes into the QWs through the side walls of the V-pits changes the distribution of holes among the MQWs. This results in a higher probability of hole injection into the middle QWs and enhanced emission therein, and, consequently, a lower efficiency droop.
引文
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[15]Kim J,Kim J,Tak Y,Chae S,Kim J Y and Park Y 2013 IEEE Electron Dev.Lett.34 1409
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[17]Quan Z,Wang L,Zheng C,Liu J and Jiang F 2014 J.Appl.Phys.116183107
[18]Kim J,Cho Y H,Ko D S,Li X S,Won J Y,Lee E,Park S H,Kim J Yand Kim S 2014 Opt.Express 22 A857
[19]Li Y,Yun F,Su X,Liu S,Ding W and Hou X 2014 J.Appl.Phys.116123101
[20]Kumakura K,Makimoto T,Kobayashi N,Hashizume T,Fukui T and Hasegawa H 2005 Appl.Phys.Lett.86 052105
[21]Ryou J H,Yoder P D,Liu J,Lochner Z,Kim H,Choi S,Kim H J and Dupuis R D 2009 IEEE J.Sel.Top.Quantum Electron.15 1080
[2]Krames M R,Shchekin O B,Mueller-Mach R,Mueller G O,Zhou L,Harbers G and Craford M G 2007 J.Disp.Technol.3 160
[3]Tan C K,Zhang J,Li X H,Liu G,Tayo B O and Tansu N 2013 J.Disp.Technol.9 272
[4]Yan Q X,Zhang S F,Long X M,Luo H J,Wu F,Fang L,Wei D P and Liao M Y 2016 Chin.Phys.Lett.33 078501
[5]Verzellesi G,Saguatti D,Meneghini M,Bertazzi F,Goano M,Meneghesso G and Zanoni E 2013 J.Appl.Phys.114 071101
[6]Akyol F,Nath D,Krishnamoorthy S,Park P and Rajan S 2012 Appl.Phys.Lett.100 111118
[7]Xu J,Schubert M F,Zhu D,Cho J,Schubert E F,Shim H and Sone C2011 Appl.Phys.Lett.99 041105
[8]Park J H,Yeong Kim D,Hwang S,Meyaard D,Fred Schubert E,Dae Han Y,Won Choi J,Cho J and Kyu Kim J 2013 Appl.Phys.Lett.103061104
[9]Chang C Y,Li H,Shih Y T and Lu T C 2015 Appl.Phys.Lett.106091104
[10]Nakamura S 1998 Science 281 956
[11]Yakimov E B 2016 Jpn.J.Appl.Phys.55 05FH04
[12]Hangleiter A,Hitzel F,Netzel C,Fuhrmann D,Rossow U,Ade G and Hinze P 2005 Phys.Rev.Lett.95 127402
[13]Okada N,Kashihara H,Sugimoto K,Yamada Y and Tadatomo K 2015J.Appl.Phys.117 025708
[14]Sheen M H,Kim S D,Lee J H,Shim J I and Kim Y W 2015 J.Electron.Mater.44 4134
[15]Kim J,Kim J,Tak Y,Chae S,Kim J Y and Park Y 2013 IEEE Electron Dev.Lett.34 1409
[16]Le L,Zhao D,Jiang D,Li L,Wu L,Chen P,Liu Z,Li Z,Fan Y and Zhu J 2012 Appl.Phys.Lett.101 252110
[17]Quan Z,Wang L,Zheng C,Liu J and Jiang F 2014 J.Appl.Phys.116183107
[18]Kim J,Cho Y H,Ko D S,Li X S,Won J Y,Lee E,Park S H,Kim J Yand Kim S 2014 Opt.Express 22 A857
[19]Li Y,Yun F,Su X,Liu S,Ding W and Hou X 2014 J.Appl.Phys.116123101
[20]Kumakura K,Makimoto T,Kobayashi N,Hashizume T,Fukui T and Hasegawa H 2005 Appl.Phys.Lett.86 052105
[21]Ryou J H,Yoder P D,Liu J,Lochner Z,Kim H,Choi S,Kim H J and Dupuis R D 2009 IEEE J.Sel.Top.Quantum Electron.15 1080