Fig. 1. Manufacturing process diagram of suspended circular μ-LED array on GaN-on-Si platform

Fig. 2. Two-dimensional morphology images of the chip taken by optical microscope. (a) Front view of the entire μ-LED chip; (b)‒(d) enlarged views of the central active regions of A1, A2, and A3

Fig. 3. Backside optical microscope images of the three samples: (a) A1, (b) A2, (c) A3. Backside 3D morphology: (d) A1, (e) A2, (f) A3

Fig. 4. Optoelectronic characteristics of three samples. (a) I-V characteristic curves; (b) series resistance and turn-on voltage; (c) C-V characteristic curves; (d) EQE variation with current; (e) luminous intensity distribution; (f) S21 parameters

Fig. 5. EL spectra, SR spectra ,and LEE of the three samples as a function of wavelength. (a) A1; (b) A2; (c) A3; (d) LEE as a function of wavelength for three samples

Fig. 6. I-V characteristics, time-dependent photovoltaic response characteristics, and photodetection performance parameters of three samples under 395 nm illumination as a function of light power density. (a)‒(c) I-V characteristics; (d)‒(f) time-dependent photovoltaic response characteristics; (g)‒(i) variations of R, EQE, and D^* with light power density

Fig. 7. Characterization of VLC transmission performance of three samples under different modulation modes. (a)‒(c) Eye diagrams of the VLC system under a 40 Mbit/s PRBS signal; (d) transmitted and received waveforms; (e) BER and maximum data rate for different QAM orders, with insets showing constellation diagrams for 4-QAM, 8-QAM, 16-QAM, and 32-QAM

Fig. 8. Characterization of VLC detection performance of three samples under different modulation modes. (a)‒(c) Eye diagrams of the three samples as PD under a 35 kbit/s PRBS signal; (d)‒(f) eye diagrams of A2 at different transmission rates; (g) PRBS signal detection waveforms of the three samples at 35 kHz; (h) PRBS signal detection waveforms of A2 at different data rates; (i) BER and maximum data rates of the three samples at different QAM orders