Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Color-tunable, phosphor-free InGaN nanowire light-emitting diode arrays monolithically integrated on silicon

Open Access Open Access

Abstract

We demonstrate controllable and tunable full color light generation through the monolithic integration of blue, green/yellow, and orange/red InGaN nanowire light-emitting diodes (LEDs). Such multi-color nanowire LED arrays are fabricated directly on Si substrate using a three-step selective area molecular beam epitaxy growth process. The lateral-arranged multi-color subpixels enable controlled light mixing at the chip-level and yield color-tunable light emission with CCT values in the range from 1900 K to 6800 K, while maintaining excellent color rendering capability. This work provides a viable approach for achieving micron and nanoscale tunable full-color LED arrays without the compromise between the device efficiency and light quality associated with conventional phosphor-based LEDs.

© 2014 Optical Society of America

Full Article  |  PDF Article
More Like This
Warm-white light-emitting diode with high color rendering index fabricated by combining trichromatic InGaN emitter with single red phosphor

Jinn-Kong Sheu, Fu-Bang Chen, Yen-Chin Wang, Chih-Chiang Chang, Shih-Hsien Huang, Chun-Nan Liu, and Ming-Lun Lee
Opt. Express 23(7) A232-A239 (2015)

High performance electron blocking layer-free InGaN/GaN nanowire white-light-emitting diodes

Barsha Jain, Ravi Teja Velpula, Ha Quoc Thang Bui, Hoang-Duy Nguyen, Trupti Ranjan Lenka, Truong Khang Nguyen, and Hieu Pham Trung Nguyen
Opt. Express 28(1) 665-675 (2020)

Color temperature tunable white light emitting diodes packaged with an omni-directional reflector

Jung-Chieh Su and Chun-Lin Lu
Opt. Express 17(24) 21408-21413 (2009)

Cited By

Optica participates in Crossref's Cited-By Linking service. Citing articles from Optica Publishing Group journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (6)

Fig. 1
Fig. 1 Illustration of the three-step substrate preparation and epitaxial growth process. (a) Si substrate was patterned by a thin SiOx layer. (b) The 1st step blue nanowire LEDs were grown on the patterned substrate. (c) The SiOx mask, together with the nanowires formed on top, were selectively removed. (d) The 1st step LEDs were covered with SiOx, and the 2nd step (green) nanowire LEDs were grown. (d) The 1st step and 2nd step LEDs were covered with SiOx, and the 3rd step (red) nanowire LEDs were grown. (e) SiOx and nanowires on SiOx were selectively removed, resulting in the formation of multi-color nanowire LED arrays on Si.
Fig. 2
Fig. 2 SEM images of (a) InGaN/GaN red-emitting nanowires grown on Si in the 3rd epitaxy step and (b) InGaN/GaN nanowires formed near the boundary between SiOx mask and open Si area. (c) Optical microscope image of multi-color nanowire LED arrays grown using the three-step MBE process after the removal of the SiOx mask. The blue, green/yellow, and orange/red-emitting nanowire LEDs grown in the 1st, 2nd, and 3rd step are denoted as 1, 2, and 3, respectively.
Fig. 3
Fig. 3 (a) Normalized PL spectra of multi-color nanowire LED subpixels monolithically grown on Si substrate measured at 300 K. (b) Schematic of multi-color nanowire LED devices on the same chip. The thickness of each layer is not drawn to scale.
Fig. 4
Fig. 4 (a) Current-voltage characteristics of 300 × 300 µm2 LED subpixels with red, yellow and green emissions. (b) Normalized EL spectra of nanowire LED subpixels monolithically integrated on Si substrate. The corresponding optical images are shown in the inset.
Fig. 5
Fig. 5 (a) Relative light power of blue, green, yellow, orange and red-emitting LED subpixels under various injection currents up to 800 mA (1% duty cycle pulsed biasing) at room-temperature. (b) The output spectra of a representative triple-color LED pixel with three 300 × 300 µm2 devices independently biased at various CW injection current, showing the wide range of tunability. A triple-color LED pixel is shown in the inset.
Fig. 6
Fig. 6 (a) CCT and CRI values of the emission measured from three triple-color LED pixels. The inset shows the corresponding locations in the CIE chromaticity diagram. (b) Normalized spectral power distribution of representative triple-color LED pixels with high CRI.

Tables (1)

Tables Icon

Table 1 Injection current and relative EQE measured for LED subpixels for the overall emission with varied CCT(CRI)s.

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved