Abstract: The present invention relates to a technique for fabricating a mechanical or visual alignment fiducial on a laser die particularly adapted for application with a laser die that is a buried structure edge emitting laser. In fabricating the device, the fiducial and the active mesa are formed in the same photolithography patterning step, using conventional techniques. The active is then buried with regrowth layers. The regrowth layers are subsequently selectively etched to expose the fiducial, leaving the active region protected and buried.

Abstract: The present invention relates to a technique for fabricating a mechanical or visual alignment fiducial on a laser die particularly adapted for application with a laser die that is a buried structure edge emitting laser. In fabricating the device, the fiducial and the active mesa are formed in the same photolithography patterning step, using conventional techniques. The active is then buried with regrowth layers. The regrowth layers are subsequently selectively etched to expose the fiducial, leaving the active region protected and buried.

Abstract: The present invention relates to a technique for fabricating a mechanical or visual alignment fiducial on a laser die particularly adapted for application with a laser die that is a buried structure edge emitting laser. In fabricating the device, the fiducial and the active mesa are formed in the same photolithography patterning step, using conventional techniques. The active is then buried with regrowth layers. The regrowth layers are subsequently selectively etched to expose the fiducial, leaving the active region protected and buried.

Abstract: The present invention relates to a technique for fabricating a mechanical or visual alignment fiducial on a laser die particularly adapted for application with a laser die that is a buried structure edge emitting laser. In fabricating the device, the fiducial and the active mesa are formed in the same photolithography patterning step, using conventional techniques. The active is then buried with regrowth layers. The regrowth layers are subsequently selectively etched to expose the fiducial, leaving the active region protected and buried.

Abstract: A connector assembly includes an active fiber needle 1 having a passive or active optical device 6 connected to an end face 7 of a thick metallized coating 4 and a cup-shaped mount 10 for hermetically enclosing the optical device. The mount 10 hermetically encloses the optical device 6 and provides heat dissipation and electrical connections for optical device 6. The cup-shaped mount may include a ceramic tubular sleeve hermetically sealed to the metal coating 4 on the fiber needle 1 about a central bore 12A thereof. Electrical connections between the optical device 6 and devices external to the mount may preferably be provided through a spring contact 18 which is soldered to terminals on device 6 and has at least one leg 18A, 18B extending through the hermetically sealed cup-shaped housing 10. Other embodiments of electrical lead connections may be provided by wire bonds 24 between device 6 and external metallization surfaces 26A.

Abstract: An optical connection for connecting an active optical device (6,52) or a passive optical device (41,63) to an optical fiber (3), having a thick metal coating (2) deposited circumferentially around the fiber. In this optical connection the device (6,52,41,63) is bonded to the polished endface of the fiber (5), with particular use being made of the thick metal surface (7) on the endface of the fiber. In another embodiment, the optical fiber (3) is etched to form various surfaces (31,32,33) for optical coupling. This etching also allows for accurate passive alignment of an etched active device (52) or a passive device (42,63) with the optical fiber.

Abstract: A method for activating the zinc dopant in an active layer of a Group III/Group V semiconductor device comprises forming a layer of zinc doped Group III/Group IV material, and thereafter annealing the layer at a predetermined temperature and for a predetermined time sufficient to convert inactive zinc in the layer to acceptor zinc. In a preferred embodiment of the invention, a method for activating zinc dopant in the active layer of an InP-InGaAsP double heterostructure comprises annealing the active layer at a temperature of about 625.degree. C. for at least about 190 seconds which converts inactive zinc to acceptor zinc without substantially decreasing the total zinc in the active layer. In another preferred embodiment, a method for increasing the power output of InP-InGaAsP optoelectronic semiconductor device, such as a laser or an LED having a zinc doped active layer, comprises annealing the active layer of the semiconductor device at a temperature of about 625.degree. C. for at least about 190 seconds.

Abstract: A method of fabricating a solid state device having chemically bound arsenic and phosphorous includes carrying out liquid phase epitaxial growth in the presence of partial pressures of arsenic and phosphorus.

Abstract: A buried hetero-structure laser diode is disclosed. The buried hetero-structure is formed by growing a double hetero-structure on a substrate. The double hetero-structure comprises two cladding layers spaced apart by a narrow bandgap active layer. Two spaced apart channels are etched in the double hetero-structure down to the lower cladding layer to define a mesa therebetween. Current blocking layers are deposited in the channels and on the portions of the double hetero-structure located outside the channels. The liquid phase epitaxy growth conditions are such that while the blocking layers are deposited in the channels and outside the channels, the upper cladding layer portion of the mesa is being melted back. Thus, the ends of the blocking layers touching the melted back mesa are separated from the active layer portion of the mesa by a thickness substantially less than the thickness of the upper cladding layer as measured in the regions outside the channels.

Abstract: In the fabrication of buried heterostructure InP/InGaAsP lasers, mask undercutting during the mesa etching step is alleviated by a combination of steps which includes the epitaxial growth of a large bandgap InGaAsP cap layer (1.05 eV.ltorsim.E.sub.g .ltorsim.1.24 eV) and the plasma deposition of a SiO.sub.2 etch masking layer. Alternatively, the cap layer may be a bilayer: an InGaAs layer or narrow bandgap InGaAsP (E.sub.g .ltorsim.1.05 eV), which has low contact resistance, and a thin InP protective layer which reduces undercutting and which is removed after LPE regrowth is complete. In both cases, etching at a low temperature with agitation has been found advantageous.

Abstract: Thermal degradation of compound single crystal substrates (e.g., InP) containing a relatively volatile element (e.g., P) prior to LPE growth has been virtually eliminated by an improved protection technique. A partial pressure of the volatile element is provided by a solution (e.g., Sn-In-P) localized inside a chamber which is external to the LPE boat and which surrounds substrate prior to growth, thereby preventing thermal damage to the substrate surface. Applicability of the technique to other epitaxial growth processes (e.g., VPE and MBE) is also discussed.

Abstract: In the fabrication of buried heterostructure InP/InGaAsP lasers, mask undercutting during the mesa etching step is alleviated by a combination of steps which includes the epitaxial growth of a large bandgap InGaAsP cap layer (1.05 eV.ltorsim.E.sub.g .ltorsim.1.24 eV) and the plasma deposition of a SiO.sub.2 etch masking layer. Alternatively, the cap layer may be a bilayer: an InGaAs layer or narrow bandgap InGaAsP (E.sub.g .ltorsim.1.05 eV), which has low contact resistance, and a thin InP protective layer which reduces undercutting and which is removed after LPE regrowth is complete. In both cases, etching at a low temperature with agitation has been found advantageous.

Abstract: Thermal degradation of compound single crystal substrates (e.g., InP) containing a relatively volatile element (e.g., P) prior to LPE growth has been virtually eliminated by an improved protection technique. A partial pressure of the volatile element is provided by a solution (e.g., Sn-In-P) localized inside a chamber which is external to the LPE boat and which surrounds substrate prior to growth, thereby preventing thermal damage to the substrate surface. Applicability of the technique to other epitaxial growth processes (e.g., VPE and MBE) is also discussed.