REVIEWS

Characteristics and techniques of GaN-based micro-LEDs for application in next-generation display

Zhou Wang, Xinyi Shan, Xugao Cui and Pengfei Tian

+ Author Affiliations

 Corresponding author: Pengfei Tian, pftian@fudan.edu.cn

PDF

Turn off MathJax

Abstract: Due to the excellent optoelectronic properties, fast response time, outstanding power efficiency and high stability, micro-LED plays an increasingly important role in the new generation of display technology compared with LCD and OLED display. This paper mainly introduces the preparation methods of the GaN-based micro-LED array, the optoelectronic characteristics, and several key technologies to achieve full-color display, such as transfer printing, color conversion by quantum dot and local strain engineering.

Key words: micro-LEDGaNfull-color displaytransfer printingcolor conversion



[1]
Lee H E, Shin J H, Park J H, et al. Micro light-emitting diodes for display and flexible biomedical applications. Adv Funct Mater, 2019, 29, 1808075 doi: 10.1002/adfm.201808075
[2]
Lee H E, Choi J, Lee S H, et al. Monolithic flexible vertical GaN light-emitting diodes for a transparent wireless brain optical stimulator. Adv Mater, 2018, 30, 1800649 doi: 10.1002/adma.201800649
[3]
Yang P, Zhang L, Kang D J, et al. High-resolution inkjet printing of quantum dot light-emitting microdiode arrays. Adv Opt Mater, 2019, 8, 1901429 doi: 10.1002/adom.201901429
[4]
Yang W, Zhang S, McKendry J J D, et al. Size-dependent capacitance study on InGaN-based micro-light-emitting diodes. J Appl Phys, 2014, 116, 044512 doi: 10.1063/1.4891233
[5]
Tian P, McKendry J J D, Gong Z, et al. Characteristics and applications of micro-pixelated GaN-based light emitting diodes on Si substrates. J Appl Phys, 2014, 115, 033112 doi: 10.1063/1.4862298
[6]
Li Y, Wu Q, Meng F Y, et al. Enhanced performance of large-area vertical light-emitting diodes treated by laser irradiation. Micro Nano Lett, 2017, 12, 369 doi: 10.1049/mnl.2016.0699
[7]
Chen X, Kong F, Li K, et al. Study of light extraction efficiency of flip-chip GaN-based LEDs with different periodic arrays. Opt Commun, 2014, 314, 90 doi: 10.1016/j.optcom.2013.09.006
[8]
Yao Y C, Hwang J M, Yang Z P, et al. Enhanced external quantum efficiency in GaN-based vertical-type light-emitting diodes by localized surface plasmons. Sci Rep, 2016, 6, 22659 doi: 10.1038/srep22659
[9]
Liu Z, Chong W C, Wong K M, et al. GaN-based LED micro-displays for wearable applications. Microelectron Eng, 2015, 148, 98 doi: 10.1016/j.mee.2015.09.007
[10]
Lin C C, Fang Y H, Kao M J, et al. Ultra-fine pitch thin-film micro LED display for indoor applications. SID Symp Dig Tech Pap, 2018, 49, 782 doi: 10.1002/sdtp.12373
[11]
Yoon J K, Park E M, Son J S, et al. The study of picture quality of OLED TV with WRGB OLEDs structure. SID Symp Dig Tech Pap, 2013, 44, 326 doi: 10.1002/j.2168-0159.2013.tb06212.x
[12]
Katsui S, Kobayashi H, Nakagawa T, et al. 5291-PPI organic light-emitting diode display using field-effect transistors including a c-axis aligned crystalline oxide semiconductor. SID Symp Dig Tech Pap, 2019, 50, 311 doi: 10.1002/sdtp.12918
[13]
Liu Z, Zhang K, Liu Y, et al. Fully multi-functional GaN-based micro-LEDs for 2500 PPI micro-displays, temperature sensing, light energy harvesting, and light detection. 64th IEEE Annual International Electron Devices Meeting, 2018, 871
[14]
JBD exhibits 2000000 nit and 10000 PPI micro-LED displays [EB/OL]. https://www.toutiao.com/i6705923322162446856/
[15]
Santos J M M, Jones B E, Schlosser P J, et al. Hybrid GaN LED with capillary-bonded II–VI MQW color-converting membrane for visible light communications. Semicond Sci Tech, 2015, 30, 035012 doi: 10.1088/0268-1242/30/3/035012
[16]
Hori A, Yasunaga D, Satake A, et al. Temperature and injection current dependence of electroluminescence intensity in green and blue InGaN single-quantum-well light-emitting diodes. J Appl Phys, 2003, 93, 3152 doi: 10.1063/1.1554475
[17]
Chong W C, Cho W K, Liu Z J, et al. 1700 pixels per inch (PPI) passive-matrix micro-LED display powered by ASIC. 2014 IEEE Compound Semiconductor Integrated Circuit Symposium (CSICS), 2014, 978-1-4799-3622-9
[18]
Fei M Q, Fei Y. The wide view-angle technique of TFT-LCD. Adv Display, 2008, 11, 22
[19]
Trindade A J, Guilhabert B, Xie E Y, et al. Heterogeneous integration of gallium nitride light-emitting diodes on diamond and silica by transfer printing. Opt Express, 2015, 23, 9329 doi: 10.1364/OE.23.009329
[20]
Han H V, Lin H Y, Lin C C, et al. Resonant-enhanced full-color emission of quantum-dot-based micro LED display technology. Opt Express, 2015, 23, 32504 doi: 10.1364/OE.23.032504
[21]
Chung K, Sui J, Demory B, et al. Color mixing from monolithically integrated InGaN-based light-emitting diodes by local strain engineering. Appl Phys Lett, 2017, 111, 041101 doi: 10.1063/1.4995561
[22]
Jiang F, Zhang J, Xu L, et al. Efficient InGaN-based yellow-light-emitting diodes. Photonics Res, 2019, 7, 144 doi: 10.1364/PRJ.7.000144
[23]
Tian P, McKendry J J, Gu E, et al. Fabrication, characterization and applications of flexible vertical InGaN micro-light emitting diode arrays. Opt Express, 2016, 24, 699 doi: 10.1364/OE.24.000699
[24]
Tian P, Althumali A, Gu E, et al. Aging characteristics of blue InGaN micro-light emitting diodes at an extremely high current density of 3.5 kA cm−2. Semicond Sci Tech, 2016, 31, 045005 doi: 10.1088/0268-1242/31/4/045005
[25]
Tian P, McKendry J J D, Herrnsdorf J, et al. Temperature-dependent efficiency droop of blue InGaN micro-light emitting diodes. Appl Phys Lett, 2014, 105, 171107 doi: 10.1063/1.4900865
[26]
Gong Z, Jin S, Chen Y, et al. Size-dependent light output, spectral shift, and self-heating of 400 nm InGaN light-emitting diodes. J Appl Phys, 2010, 107, 013103 doi: 10.1063/1.3276156
[27]
Zhang K, Peng D, Lau K M, et al. Fully-integrated active matrix programmable UV and blue micro-LED display system-on-panel (SoP). J Soc Inf Display, 2017, 25, 240 doi: 10.1002/jsid.550
[28]
Herrnsdorf J, McKendry J J D, Zhang S, et al. Active-matrix GaN micro light-emitting diode display with unprecedented brightness. IEEE T Electron Dev, 2015, 62, 1918 doi: 10.1109/TED.2015.2416915
[29]
Tull B R, Twu N, Hsu Y J, et al. Micro-LED microdisplays by integration of III–V LEDs with silicon thin film transistors. SID Symp Dig Tech Pap, 2017, 48, 246 doi: 10.1002/sdtp.11680
[30]
Cao J, Liu X, Khan M A, et al. RGB tricolor produced by white-based top-emitting organic light-emitting diodes with microcavity structure. Curr Appl Phys, 2007, 7, 300 doi: 10.1016/j.cap.2006.09.002
[31]
Sato Y, Takahashi N, Sato S. Full-color fluorescent display devices using a near-UV light-emitting diode. Jpn J Appl Phys, 1996, 35, L838 doi: 10.1143/JJAP.35.L838
[32]
Kim B H, Nam S, Oh N, et al. Multilayer transfer printing for pixelated, multi-color quantum dot light-emitting diodes. ACS Nano, 2016, 10, 4920 doi: 10.1021/acsnano.5b06387
[33]
Lin H Y, Sher C W, Hsieh D H, et al. Optical cross-talk reduction in a quantum-dot-based full-color micro-light-emitting-diode display by a lithographic-fabricated photoresist mold. Photonics Res, 2017, 5, 411 doi: 10.1364/PRJ.5.000411
[34]
Liu Z, Chong W C, Wong K M, et al. A novel BLU-free full-color LED projector using LED on silicon micro-displays. IEEE Photonic Tech Lett, 2013, 25, 2267 doi: 10.1109/LPT.2013.2285229
[35]
Display technology of micro-LED has the most potential application in AR/VR display device [EB/OL]. http://www.51touch.com/lcd/news/dynamic/2017/1031/48607.html
[36]
Color conversion is a feasible way for micro LED display technology to achieve mass production [EB/OL]. http://www.yejibang.com/news-details-23615.html
Fig. 1.  (Color online) (a) The GaN-based epitaxial structure with silicon substrate. (b) Etching to n-GaN layer to form a micro-LED mesa array. (c) The deposition of SiO2 through PECVD. (d) The deposition of Ti/Au to serve as electrodes.

Fig. 2.  (Color online) (a) I–V curves of blue micro-LED pixels with different sizes. (b) The curve of current density for blue micro-LED with different sizes.

Fig. 3.  (Color online) (a) L–I curves of blue micro-LEDs with different diameters. (b) The curve of the light-output power density versus injection current density for blue micro-LED with different sizes.

Fig. 4.  (Color online) (a) EQE versus current density from 300 to 500 K with 25 K temperature increment on a semi-logarithmic scale. (b) Bandwidth versus current from 300 to 425 K to show the trend with temperature[25]. Copyright 2014, Applied Physics Letters.

Fig. 5.  (Color online) (a) The schematic of passive matrix micro-LED array[16]. (b) The schematic of active matrix micro-LED array[28]. Copyright 2015, IEEE Transactions on Electron Devices.

Fig. 6.  (Color online) Schematic of transfer printing using capillary bonding. (a) Using an elastomeric stamp for the pick-up of a suspended micro-LED. (b) Upon pick-up, micro-LED is compressed against an acetone-wetted cloth. (c) Released micro-LED when the backside contacts receiving substrate. (d) After thermal curing, the micro-LED is bonded to the new substrate[19]. Copyright 2015, Optics Express.

Fig. 7.  (Color online) (a) Standard MQW LED was grown on sapphire substrates for the micro-LED arrays. (b) The using of aerosol jet printing method to spray the red QDs on the micro-LED array. (c) The spraying of green QDs on the micro-LED array. (d) The spraying of blue QDs on the micro-LED array. (e) The DBR was added to the top of micro LED arrays[20]. Copyright 2015, Optic Express.

Fig. 8.  (Color online) Schematic of the fabrication process for the RGB LED pixel. (a) The fabrication of nanopillar structures by photolithography and etching. (b) Planarization and electrical insulation treatment. (c) Formation of electrical interconnect[21]. Copyright 2017, Applied Physics Letters.

Table 1.   The comparison of main characteristics of micro-LED, LCD, and OLED.

ParameterLCDOLEDmicro-LED
Emission typeBacklight/LED (thick)Self-emissive (thin)Self-emissive (thin)
Brightness (cd/m2)30005000100 000[1]
Luminescent materialInorganicOrganicInorganic
Contrast ratio5000 : 1[1]
PPI> 3001500–6000[12]1500–10 000[14, 17]
Color gamut75%, NTSC> 100%, NTSC> 100%, NTSC[1]
Viewing angleBest (~178°)[18]Best (~178°)Best (~178°)[1]
Response time5 ms, slow10 μs, medium0.2 ns, fast[1]
LifetimeMediumMediumLong[1]
Operating temperature233–373 K238–358 K15–500 K[1, 12, 15]
DownLoad: CSV
[1]
Lee H E, Shin J H, Park J H, et al. Micro light-emitting diodes for display and flexible biomedical applications. Adv Funct Mater, 2019, 29, 1808075 doi: 10.1002/adfm.201808075
[2]
Lee H E, Choi J, Lee S H, et al. Monolithic flexible vertical GaN light-emitting diodes for a transparent wireless brain optical stimulator. Adv Mater, 2018, 30, 1800649 doi: 10.1002/adma.201800649
[3]
Yang P, Zhang L, Kang D J, et al. High-resolution inkjet printing of quantum dot light-emitting microdiode arrays. Adv Opt Mater, 2019, 8, 1901429 doi: 10.1002/adom.201901429
[4]
Yang W, Zhang S, McKendry J J D, et al. Size-dependent capacitance study on InGaN-based micro-light-emitting diodes. J Appl Phys, 2014, 116, 044512 doi: 10.1063/1.4891233
[5]
Tian P, McKendry J J D, Gong Z, et al. Characteristics and applications of micro-pixelated GaN-based light emitting diodes on Si substrates. J Appl Phys, 2014, 115, 033112 doi: 10.1063/1.4862298
[6]
Li Y, Wu Q, Meng F Y, et al. Enhanced performance of large-area vertical light-emitting diodes treated by laser irradiation. Micro Nano Lett, 2017, 12, 369 doi: 10.1049/mnl.2016.0699
[7]
Chen X, Kong F, Li K, et al. Study of light extraction efficiency of flip-chip GaN-based LEDs with different periodic arrays. Opt Commun, 2014, 314, 90 doi: 10.1016/j.optcom.2013.09.006
[8]
Yao Y C, Hwang J M, Yang Z P, et al. Enhanced external quantum efficiency in GaN-based vertical-type light-emitting diodes by localized surface plasmons. Sci Rep, 2016, 6, 22659 doi: 10.1038/srep22659
[9]
Liu Z, Chong W C, Wong K M, et al. GaN-based LED micro-displays for wearable applications. Microelectron Eng, 2015, 148, 98 doi: 10.1016/j.mee.2015.09.007
[10]
Lin C C, Fang Y H, Kao M J, et al. Ultra-fine pitch thin-film micro LED display for indoor applications. SID Symp Dig Tech Pap, 2018, 49, 782 doi: 10.1002/sdtp.12373
[11]
Yoon J K, Park E M, Son J S, et al. The study of picture quality of OLED TV with WRGB OLEDs structure. SID Symp Dig Tech Pap, 2013, 44, 326 doi: 10.1002/j.2168-0159.2013.tb06212.x
[12]
Katsui S, Kobayashi H, Nakagawa T, et al. 5291-PPI organic light-emitting diode display using field-effect transistors including a c-axis aligned crystalline oxide semiconductor. SID Symp Dig Tech Pap, 2019, 50, 311 doi: 10.1002/sdtp.12918
[13]
Liu Z, Zhang K, Liu Y, et al. Fully multi-functional GaN-based micro-LEDs for 2500 PPI micro-displays, temperature sensing, light energy harvesting, and light detection. 64th IEEE Annual International Electron Devices Meeting, 2018, 871
[14]
JBD exhibits 2000000 nit and 10000 PPI micro-LED displays [EB/OL]. https://www.toutiao.com/i6705923322162446856/
[15]
Santos J M M, Jones B E, Schlosser P J, et al. Hybrid GaN LED with capillary-bonded II–VI MQW color-converting membrane for visible light communications. Semicond Sci Tech, 2015, 30, 035012 doi: 10.1088/0268-1242/30/3/035012
[16]
Hori A, Yasunaga D, Satake A, et al. Temperature and injection current dependence of electroluminescence intensity in green and blue InGaN single-quantum-well light-emitting diodes. J Appl Phys, 2003, 93, 3152 doi: 10.1063/1.1554475
[17]
Chong W C, Cho W K, Liu Z J, et al. 1700 pixels per inch (PPI) passive-matrix micro-LED display powered by ASIC. 2014 IEEE Compound Semiconductor Integrated Circuit Symposium (CSICS), 2014, 978-1-4799-3622-9
[18]
Fei M Q, Fei Y. The wide view-angle technique of TFT-LCD. Adv Display, 2008, 11, 22
[19]
Trindade A J, Guilhabert B, Xie E Y, et al. Heterogeneous integration of gallium nitride light-emitting diodes on diamond and silica by transfer printing. Opt Express, 2015, 23, 9329 doi: 10.1364/OE.23.009329
[20]
Han H V, Lin H Y, Lin C C, et al. Resonant-enhanced full-color emission of quantum-dot-based micro LED display technology. Opt Express, 2015, 23, 32504 doi: 10.1364/OE.23.032504
[21]
Chung K, Sui J, Demory B, et al. Color mixing from monolithically integrated InGaN-based light-emitting diodes by local strain engineering. Appl Phys Lett, 2017, 111, 041101 doi: 10.1063/1.4995561
[22]
Jiang F, Zhang J, Xu L, et al. Efficient InGaN-based yellow-light-emitting diodes. Photonics Res, 2019, 7, 144 doi: 10.1364/PRJ.7.000144
[23]
Tian P, McKendry J J, Gu E, et al. Fabrication, characterization and applications of flexible vertical InGaN micro-light emitting diode arrays. Opt Express, 2016, 24, 699 doi: 10.1364/OE.24.000699
[24]
Tian P, Althumali A, Gu E, et al. Aging characteristics of blue InGaN micro-light emitting diodes at an extremely high current density of 3.5 kA cm−2. Semicond Sci Tech, 2016, 31, 045005 doi: 10.1088/0268-1242/31/4/045005
[25]
Tian P, McKendry J J D, Herrnsdorf J, et al. Temperature-dependent efficiency droop of blue InGaN micro-light emitting diodes. Appl Phys Lett, 2014, 105, 171107 doi: 10.1063/1.4900865
[26]
Gong Z, Jin S, Chen Y, et al. Size-dependent light output, spectral shift, and self-heating of 400 nm InGaN light-emitting diodes. J Appl Phys, 2010, 107, 013103 doi: 10.1063/1.3276156
[27]
Zhang K, Peng D, Lau K M, et al. Fully-integrated active matrix programmable UV and blue micro-LED display system-on-panel (SoP). J Soc Inf Display, 2017, 25, 240 doi: 10.1002/jsid.550
[28]
Herrnsdorf J, McKendry J J D, Zhang S, et al. Active-matrix GaN micro light-emitting diode display with unprecedented brightness. IEEE T Electron Dev, 2015, 62, 1918 doi: 10.1109/TED.2015.2416915
[29]
Tull B R, Twu N, Hsu Y J, et al. Micro-LED microdisplays by integration of III–V LEDs with silicon thin film transistors. SID Symp Dig Tech Pap, 2017, 48, 246 doi: 10.1002/sdtp.11680
[30]
Cao J, Liu X, Khan M A, et al. RGB tricolor produced by white-based top-emitting organic light-emitting diodes with microcavity structure. Curr Appl Phys, 2007, 7, 300 doi: 10.1016/j.cap.2006.09.002
[31]
Sato Y, Takahashi N, Sato S. Full-color fluorescent display devices using a near-UV light-emitting diode. Jpn J Appl Phys, 1996, 35, L838 doi: 10.1143/JJAP.35.L838
[32]
Kim B H, Nam S, Oh N, et al. Multilayer transfer printing for pixelated, multi-color quantum dot light-emitting diodes. ACS Nano, 2016, 10, 4920 doi: 10.1021/acsnano.5b06387
[33]
Lin H Y, Sher C W, Hsieh D H, et al. Optical cross-talk reduction in a quantum-dot-based full-color micro-light-emitting-diode display by a lithographic-fabricated photoresist mold. Photonics Res, 2017, 5, 411 doi: 10.1364/PRJ.5.000411
[34]
Liu Z, Chong W C, Wong K M, et al. A novel BLU-free full-color LED projector using LED on silicon micro-displays. IEEE Photonic Tech Lett, 2013, 25, 2267 doi: 10.1109/LPT.2013.2285229
[35]
Display technology of micro-LED has the most potential application in AR/VR display device [EB/OL]. http://www.51touch.com/lcd/news/dynamic/2017/1031/48607.html
[36]
Color conversion is a feasible way for micro LED display technology to achieve mass production [EB/OL]. http://www.yejibang.com/news-details-23615.html
  • Search

    Advanced Search >>

    GET CITATION

    shu

    Export: BibTex EndNote

    Article Metrics

    Article views: 4581 Times PDF downloads: 156 Times Cited by: 0 Times

    History

    Received: 21 January 2020 Revised: 08 February 2020 Online: Accepted Manuscript: 19 February 2020Uncorrected proof: 25 February 2020Published: 10 April 2020

    Catalog

      Email This Article

      User name:
      Email:*请输入正确邮箱
      Code:*验证码错误
      Zhou Wang, Xinyi Shan, Xugao Cui, Pengfei Tian. Characteristics and techniques of GaN-based micro-LEDs for application in next-generation display[J]. Journal of Semiconductors, 2020, 41(4): 041606. doi: 10.1088/1674-4926/41/4/041606 Z Wang, X Y Shan, X G Cui, P F Tian, Characteristics and techniques of GaN-based micro-LEDs for application in next-generation display[J]. J. Semicond., 2020, 41(4): 041606. doi: 10.1088/1674-4926/41/4/041606.Export: BibTex EndNote
      Citation:
      Zhou Wang, Xinyi Shan, Xugao Cui, Pengfei Tian. Characteristics and techniques of GaN-based micro-LEDs for application in next-generation display[J]. Journal of Semiconductors, 2020, 41(4): 041606. doi: 10.1088/1674-4926/41/4/041606

      Z Wang, X Y Shan, X G Cui, P F Tian, Characteristics and techniques of GaN-based micro-LEDs for application in next-generation display[J]. J. Semicond., 2020, 41(4): 041606. doi: 10.1088/1674-4926/41/4/041606.
      Export: BibTex EndNote

      Characteristics and techniques of GaN-based micro-LEDs for application in next-generation display

      doi: 10.1088/1674-4926/41/4/041606
      More Information
      • Corresponding author: pftian@fudan.edu.cn
      • Received Date: 2020-01-21
      • Revised Date: 2020-02-08
      • Published Date: 2020-04-01

      Catalog

        /

        DownLoad:  Full-Size Img  PowerPoint
        Return
        Return