| 摘要 |
A VCSEL includes an intracavity epitaxial layer including a shallow mesa (150) that alters the optical mode of the vertical cavity, laterally confining the optical mode in an otherwise planar epitaxial cavity. The VCSEL has optical confinement and current confinement within nearly the same active area (120) and can operate with low threshold current, high efficiency, or high speed. A mode confining region (160) may be defined using lithography, eliminating external process variations such as composition or thickness variations from influencing the mode confining region's (160) size. The result is a highly uniform structure across a semiconductor wafer and from wafer to wafer. The optical and current confinement regions are self-aligned because the same steps are used to form both. Alternatively, the optical mode area is substantially different from the current injection area of the active material (120), but these area are concentric or nearly concentric. |
