Rapid modulation bandwidth test system of micro-LED based on photon excitation.

Modulation bandwidth is essential for micro-LED in visible light communication systems. The traditional electroluminescence-based bandwidth test system (EL-BW-Test) is time-consuming and inevitably causes irreversible damage. This paper introduces the design and construction of a novel, to the best of our knowledge, photon-excited bandwidth testing system (PL-BW-Test), capable of swiftly acquiring the bandwidth of LED epi-wafers and devices. Comparison and experimental results demonstrated that the LED bandwidth measurements obtained via PL-BW-Test exhibit consistency with those acquired through EL-BW-Test, particularly concerning the excitation intensity and quantum well structure. The newly invented system presents several advantages including easy operation, broad applicability, and non-destructiveness, offering an innovative approach to an efficient, non-contact modulation bandwidth measurement.