MOVPE grown Bragg stacks for microresonator devices

Atmospheric pressure MOVPE has been used to prepare DBR structures for applications in reflection modulators and vertical lasers. Two styles of DBR have been investigated, a simple two element stack and a four component design necessary to reduce the series resistance associated with the large band discontinuities of the AlAs-GaAs system. A VSEL showed a reduction in operating voltage by four when intermediate layers were included at each interface of the DBR. Reflectivity and X-ray diffraction can be used to characterise the operating wavelength and periodic length of the DBR respectively