Light emitting semiconductor devices such as VCSELs, SELs, and LEDs are manufactured to have a thin electrical confinement barrier in a confining layer near the active region of the device. The thin confinement barrier comprises a III-V semiconductor material having a high aluminum content (e.g. 80%-100% of the type III material). The aluminum content of the adjacent spacer layer is lower than that of the confinement barrier. In one embodiment the spacer layer has an aluminum content of less than 40% and a direct bandgap. The aluminum profile reduces series resistance and improves the efficiency of the semiconductor device.