Very-lowtemperature molecular beam epitaxial growth of GaP/AlAs heterostructures for Distributed Bragg Reflector applications

摘要

[[abstract]]Using very-low-temperature (VLT) molecular beam epitaxy (MBE), (Ga,P)/(Al,As) heterostructures were grown for use in a distributed Bragg reflector (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 for both materials. Also, the growth rate is highly dependent on the group-V overpressure due to the high sticking coefficients of both As and P at these low growth temperatures. Using lateral oxidation, the amorphous AlAs was converted to its oxide for use in a visible wavelength DBR. Variabilities within layer thickness, especially the amorphous AlAs layers, were investigated to determine their effect on the DBR reflectivities. Different DBR designs were employed resulting in a double passband DBR which is highly reflective at wavelengths of both 550 and 1100 nm.