Fabrication of GaP/Al-oxide distributed Bragg reflectors for visible spectrum

[[abstract]]Using very-low temperature (VLT) molecular-beam epitaxy (MBE), polycrystalline GaP/Al–oxide distributed Bragg reflectors (DBRs) have been fabricated. The use of high-energy band gap materials, such as GaP, allows for applications in the visible spectrum with minimal absorption of photons in the DBR. Through the use of VLT-MBE and control of the group-V overpressure, the microstructure can be controlled, resulting in either amorphous or polycrystalline material. Due to the nature of the amorphous material, the requirement of lattice matching is relaxed with no adverse effects to the underlying single crystal material. Two DBRs were fabricated, one reflecting at a wavelength of 550 nm and the other 480 nm. Using six pairs of polycrystalline GaP/Al–oxide, a reflectivity of ∼95% was achieved indicating a high-quality DBR suitable for device use.[[fileno]]2030161010048[[department]]電機工程學