Coupled cavity anti-guided vertical-cavity surface-emitting laser

• Main Authors: GUNTER JAMES, JOHNSON RALPH HERBERT, CLARK ANDREW
• Format: Patent
• Language: English
• Published: 25.06.2002
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; DEVICES USING STIMULATED EMISSION; ELECTRICITY

A laser structure (10, 60) and method of manufacturing a vertical-cavity surface-emitting laser (VCSEL). The laser structure (10, 60) is adapted to lase at a wavelength lambda and includes a first mirror stack (14), an active region (18) disposed on the first mirror stack (14) and a second mirror stack (22) disposed on the active region (18). The second mirror stack (22) includes a plurality of alternating mirror layer pairs (a, b) with a phase shifting region (24) disposed therein. The phase shifting region (24) is positioned outside the optical aperture (25) and away from the active region (18) by at least one mirror layer pair, with the optical thickness of the phase shifting region (24) being a multiple of one-fourth lambda, the phase shifting region (24) being oxidized reducing the reflectance of the second mirror stack (22) outside the aperture relative to inside the aperture. The optical thickness of the phase shifting region (24) is a function of the difference between the index of refraction of an adjacent semiconductor layer and the index of refraction of the phase shifting region. The phase shifting region (24) creates a coupled cavity (25, 68) positioned above the active region (18). The phase shifting region (24) reduces the reflectance of the second mirror stack (22) and may be positioned at a node of the laser electric field inside the aperture.