Fig. 1. (a) Schematic epitaxial structure. (b) HRTEM image of the QWs. (c) ω-2θ scan of the epitaxial layer. (d) ω-scan rocking curves of (0002) and (10-12) planes.

Fig. 2. (a) TDPL spectra of the InGaN QDs sample. (b) Peak wavelength and FWHM of TDPL spectra versus measurement temperatures. (c) PL decay curve of the InGaN QDs sample at 300 K.

Fig. 3. (a) Voltage-current and optical power-current characteristics of InGaN QDs LEDs. (b) EL spectra of the InGaN QDs LEDs with injection current varying. (c) The change of red, green, and blue peaks’ position with injection current varying. (d) Intensity ratio in red, green, and blue peaks versus injection current. (e) EL images of InGaN QDs LEDs at injection currents of 5, 10, 20, 100, and 150 mA.

Fig. 4. Schematic illustration of the carrier recombination mechanism of InGaN QDs based single chip WLED.

Fig. 5. (a) CIE-1931 chromaticity coordinates. (b) CCT and CRI of single chip WLED versus injection current.

Fig. 6. (a) The frequency response and (b) bandwidth of single chip WLED versus injection current density. (c) EL spectra of the single chip WLED at 72  A/cm2 (90 mA), with the corresponding EL image in the inset.

Fig. 7. (a) The BER and (b) eye diagram versus the data rate of single chip WLED at 72  A/cm2 (90 mA).

Table 1. Comparison of the Characteristics of GaN-Based WLEDs