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Presents data on the photopumped room temperature continuous operation of native-oxide-embedded quantum-well-heterostructure lasers. Experimental details; Results; Conclusions.

Demonstrates the continuous room-temperature operation of planar index-guided burried-mesa heterostructure visible-spectrum laser diodes. Basis for a system of III-V semiconductor laser lamps with possible wavelengths; Formation of the planar mesa structure; Schematic diagram of the heterostructure laser crystals employed.

Based upon temporal measurements of interface electrical conductivity from current-voltage characterization and interface micromorphologies from transmission electron microcopy, a kinetic analysis of the thermally induced interfacial transformation process of GaAs/GaAs semiconductor interfaces fabricated by wafer bonding technology is performed. The activation energy required for the overall interface transformation that involves defect and atomic diffusion was determined to be 0.75 eV. A physical model of this transformation process is proposed. [ABSTRACT FROM AUTHOR]

A novel metallic bonding method using AuGeNiCr as the bonding medium was developed for the fabrication of long-wavelength vertical-cavity surface-emitting lasers (VCSELs). The metallic bonding process can be performed at a low temperature of 320 °C within 1 h and it does not require chemical-mechanical polishing or etching treatments on the bonding surfaces. As determined by atomic force microscopy, the process can tolerate a surface roughness of ∼ 10 nm on the surface of bonding samples. Cross-sectional transmission electron microscopy shows that the bonding interface is smooth and damage-free. Using this bonding technique, a 1.55 µm GalnAsP/InPVCSEL structure with Al-oxide/Si distributed Bragg reflectors was demonstrated on a Si substrate. No degradation was found on the bonded VCSEL structure after annealing at 420 °C. The reflectivity and resonance measured from the bonded VCSEL cavity confirmed the high optical quality provided by this bonding process for device fabrication. [ABSTRACT FROM AUTHOR]

The joint strength and microstructure of fluxless Au/Sn solders in InP-based laser-diode packages after thermal-aging testing were studied experimentally and numerically. Specimens were aged at 150°C for up to 64 days. The joint strength decreased as aging time increased. The microstructure and fracture surface of the Au/Sn solder joints showed that the joint strength decrease was caused by both the enlargement of the initial voids and an increase in the number of voids as the aging time increased. Finite-element method (FEM) simulations of joint strength were in good agreement with experimental measurements. Both experimental and numerical results indicate that the enlargement of the initial voids and an increase in the number of voids, caused by stress concentration as the aging period increased, resulted in the weakness of joint strength. The effect of temperature-cycling testing on the power variation of the InP laser diodes using fluxless Au/Sn solders was also studied. It was shown that the laser diodes operated in the stable condition up to 500 cycles. [ABSTRACT FROM AUTHOR]

High-power operation of hydrogenated AlyGa1-yAs-GaAs-InxGa1-xAs ten-stripe arrays operating at λ∼1.06 μm is described. Continuous (cw) operation of arrays with uncoated facets that are stabilized in temperature at 10 °C has produced output powers as high as 375 mW/facet at 1.4 A. The optical coupling of the gain-guided arrays is shown to be significantly different from otherwise similar arrays fabricated in the AlyGa1-yAs-GaAs system. Limited ‘‘lifetesting’’ (168 h) of these strained layer diodes, stabilized at 50 °C and a cw output power of 100 mW/facet (200 mW total), indicates good operating stability. [ABSTRACT FROM AUTHOR]

We describe the construction and room-temperature (300 K) continuous (cw) operation of p-n diode AlxGa1-xAs-GaAs quantum well heterostructure (QWH) lasers grown on Si substrates. The QWH crystal is grown in two stages, the first part by molecular beam epitaxy (MBE) and the single-well quantum well active region by metalorganic chemical vapor deposition (MOCVD). Simple gain-guided stripe configuration lasers fabricated on the MBE MOCVD QWH wafer operate cw at 300 K and have pulsed thresholds as low as 1.8×103 A/cm2. [ABSTRACT FROM AUTHOR]

We report the first continuous wave room-temperature InGaAs-GaAs-AlGaAs strained-layer semiconductor laser diode grown by molecular beam epitaxy. The laser is a multiple quantum well transverse junction stripe laser with a lateral heterojunction fabricated by zinc diffusion enhanced compositional disordering. The low-threshold (20 mA) and single-mode performance of the laser demonstrates that a high-quality lateral p+-p-n junction and lateral heterobarrier can be formed by zinc diffusion compositional disordering of a strained-layer InGaAs-GaAs-AlGaAs quantum well heterostructure. [ABSTRACT FROM AUTHOR]

Data are presented demonstrating continuous (cw) room-temperature photopumped laser operation of an AlxGa1-xAs-GaAs quantum well heterostructure (QWH) grown on a Si substrate. The QWH is grown in a two-step process with first the GaAs grown on the Si substrate by molecular beam epitaxy (MBE) and second the QWH grown by metalorganic chemical vapor deposition (MOCVD). The MBE GaAs contains a thin 600-Å layer at the Si/GaAs interface that is rich in defects, ‘‘absorbs’’ much of the mismatch, and provides a good surface (specular surface) for the MOCVD growth of the QWH. Although cw 300 K laser operation is obtained, it occurs at high threshold and is short lived, agreeing with earlier results on the cw 300 K laser operation of mismatched III-V QWH’s. [ABSTRACT FROM AUTHOR]

We report the first cw, room-temperature multiple quantum well transverse junction stripe laser (MQW TJS) with an alloy disordered heterobarrier. The addition of a lateral heterobarrier by zinc diffusion enhanced alloy disordering reduces the laser threshold by a factor of 3 compared to standard transverse junction stripe lasers processed simultaneously. The reduction in threshold and excellent single mode performance of the MQW TJS are attributed to the superior carrier and optical confinement of a single heterojunction compared to a homojunction. We demonstrate for the first time lateral injection in a multiple quantum well where the diffused junction plays an active (not passive) role in the injection process and that the transition region between complete disorder and no disorder forms the active region of the laser. [ABSTRACT FROM AUTHOR]

Impurity-free selective layer disordering, utilizing Si3N4 masking stripes and SiO2 defect (vacancy) sources, is used to realize room-temperature continuous AlxGa1-xAs-GaAs quantum well heterostructure lasers. [ABSTRACT FROM AUTHOR]

The temperature dependence of threshold current of quantum well heterostructure (QWH) laser diodes is reduced by inserting (Si2)x(GaAs)1-x barriers in the active region. Alloy clustering of the (Si2)x(GaAs)1-x barriers, grown by metalorganic chemical vapor deposition, leads to further QW carrier localization and an increase in T0 in the usual expression Jth=J0 exp(T/T0) for the threshold current. Values as high as T0=250–275 °C have been measured. [ABSTRACT FROM AUTHOR]

Data are presented showing that the alloy (Si2)x(GaAs)1-x can be formed in a GaAs quantum well (QW) and shifts the operation of an AlxGa1-xAs-GaAs QW laser to higher energy. The (Si2)x(GaAs)1-x barrier, which is formed by sheet deposition (metalorganic chemical vapor deposition) of Si on the initial portion of a GaAs QW layer and then by ‘‘capping’’ this with the remaining part of the QW, can be observed directly by transmission electron microscopy. [ABSTRACT FROM AUTHOR]