Improved Modulation Bandwidth of c-Plane Micro-LED Arrays by Varying Si Doping in the Quantum Barrier

Abstract-Visible light communication (VLC) is an important complementary technology to traditional radio frequency (RF) communication due to the abundance of available frequency resources and the high data rates. VLC systems are, however, constrained by the low −3 dB bandwidth of light-emitting diodes (LED) and high bit error rates (BER). Herein, we propose a vertical-structure microLED array with an Si-doped first quantum barrier (FQB) that suppresses the quantum confinement Stark effect (QCSE), increasing the radiative recombination rate. The micro-LED array exhibits an −3 dB bandwidth of 578 MHz at 2000 A / cm2 when the Si doping content of the FQB is
$8 \times 10^{18} \mathrm{~cm}^{-3}$
. A data rate of
$1.61 \mathrm{~Gb} / \mathrm{s}$
with a BER of
$3.51 \times 10^{-3}$
over the distance of 1 m free space was demonstrated using the on-off keying (OOK) modulation scheme. This work shows great potential for high-speed VLC systems by proposing a simple way to improve communication performance.