Decreasing parasitic capacitance in vertical-cavity surface-emitting laser with selectively oxidized aperture

Results of a comparative study of the structural parameters and the static and dynamic characteristics of vertical-cavity surface-emitting lasers (VCSELs) with microresonators based on Al$_{0.15}$Ga$_{0.85}$As and Al$_{0.8}$Ga$_{0.2}$As are presented. It is established that the vertical oxidation of layers in the Al$_{0.8}$Ga$_{0.2}$As microresonator during formation of the current aperture leads to a significant increase in the oxide thickness. This leads to a considerable decrease in parasitic capacitance of the device and a 1.7- to 2-fold growth in the cut-off frequency of a low-frequency filter formed by parasitic elements of the equivalent electric scheme of the device.