Co-integration of mesoporous GaN distributed Bragg reflectors and light-emitting diodes by transfer printing

Transfer printing is employed to demonstrate the integration of gallium nitride (GaN)-based distributed Bragg reflectors (DBR) with 100 μm lateral dimensions and reflectance of 90% in various formats. Mesoporous GaN DBRs are utilized as basic building blocks to fabricate more complex photonic devices directly on Silicon (Si) and glass receiving substrates. Multi-mode optical resonant cavities centered at 450 nm on Si are thus formed by direct stacking of two mesoporous DBR membranes. Furthermore, active devices are also demonstrated by combining mesoporous DBR with GaN-based light-emitting diodes membranes of similar dimensions, resulting in a Fabry-Perot-mediated emission with its main peak shifted by 14 nm compared to a reference device without DBR. Measured optical bandwidth of 136 MHz (-6 dB) in a small signal modulation scheme is also demonstrated from these devices.