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12 Oct 1987

Volume 51, Issue 15, pp. 1129-1202


High‐speed diffusion‐driven photodetector

Adnah G. Kostenbauder

Appl. Phys. Lett. 51, 1129 (1987); http://dx.doi.org/10.1063/1.98760 (3 pages) | Cited 4 times

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We describe a novel ultrafast photodetector based upon combining the Dember effect and optically generated fine carrier gratings. We present experimental data on prototype devices, and demonstrate that this device’s response time is limited neither by the carrier lifetime nor by the saturation‐velocity transit time.
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85.60.Gz Photodetectors (including infrared and CCD detectors)
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
72.40.+w Photoconduction and photovoltaic effects
06.60.Jn High-speed techniques (microsecond to femtosecond)

Low‐loss InGaAs/InP multiple quantum well optical electroabsorption waveguide modulator

U. Koren, B. I. Miller, T. L. Koch, G. Eisenstein, R. S. Tucker, I. Bar‐Joseph, and D. S. Chemla

Appl. Phys. Lett. 51, 1132 (1987); http://dx.doi.org/10.1063/1.98761 (3 pages) | Cited 28 times

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An optical electroabsorption waveguide modulator is described based on the quantum‐confined Stark effect in an InGaAs/InP multiple quantum well waveguide. The optical modulator has a high on/off ratio (47:1) with very low insertion loss (2.9 dB) and a 3‐dB modulation bandwidth of 3.0 GHz at 0.1 mW optical input power.
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42.79.Hp Optical processors, correlators, and modulators
42.79.Gn Optical waveguides and couplers
78.20.Jq Electro-optical effects

Ultrafast all‐optical switching in a dual‐core fiber nonlinear coupler

S. R. Friberg, Y. Silberberg, M. K. Oliver, M. J. Andrejco, M. A. Saifi, and P. W. Smith

Appl. Phys. Lett. 51, 1135 (1987); http://dx.doi.org/10.1063/1.98762 (3 pages) | Cited 86 times

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We report the first demonstration of a nonlinear coupler switch capable of substantially complete all‐optical switching at subpicosecond rates with no light‐induced thermal effects.
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42.65.Pc Optical bistability, multistability, and switching, including local field effects
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks

Monolithic two‐dimensional surface‐emitting arrays of GaAs/AlGaAs diode lasers

J. P. Donnelly, W. D. Goodhue, T. H. Windhorn, R. J. Bailey, and S. A. Lambert

Appl. Phys. Lett. 51, 1138 (1987); http://dx.doi.org/10.1063/1.98763 (3 pages) | Cited 16 times

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Monolithic two‐dimensional arrays with light emission normal to the surface have been obtained by fabricating edge‐emitting quantum well GaAs/AlGaAs lasers with deflecting mirrors adjacent to both laser facets. The facets and mirrors were formed by ion beam assisted etching. Proton bombardment between adjoining lasers was used to prevent lasing in the transverse direction. At the highest pulsed current used in these experiments, 10.5 A, the power output of a 22‐element array was 1.6 W, which corresponds to a power density of 160 W cm−2. At this level, the power output was still linear with current.
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42.60.By Design of specific laser systems
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation

Narrow linewidth 1.5 μm semiconductor laser with a resonant optical reflector

N. A. Olsson, C. H. Henry, R. F. Kazarinov, H. J. Lee, B. H. Johnson, and K. J. Orlowsky

Appl. Phys. Lett. 51, 1141 (1987); http://dx.doi.org/10.1063/1.98764 (2 pages) | Cited 2 times

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A compact narrow linewidth semiconductor laser is described. An emission linewidth of 135 kHz at 5 mW of output power is obtained from a 1.5‐μm semiconductor laser butt coupled to an external resonant optical reflector (ROR). The ROR, made with dielectric waveguides on silicon substrate, has transmission and reflection bandwidths as narrow as 0.35 Å.
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42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.79.Gn Optical waveguides and couplers
42.55.Px Semiconductor lasers; laser diodes

Growth of α‐Al2O3 films by molecular layer epitaxy

Gin‐ichiro Oya, Munehiro Yoshida, and Yasuji Sawada

Appl. Phys. Lett. 51, 1143 (1987); http://dx.doi.org/10.1063/1.98765 (3 pages) | Cited 6 times

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Single‐crystal α‐Al2O3 films are, for the first time, successfully grown on sapphire wafers above ∼600 °C by the molecular layer epitaxy (MLE) method using AlCl3 vapor and a He 15%O2 gas mixture. The average growth rate observed barely depends on the substrate temperature, being ∼0.09 nm per cycle of gas transport, under the used growth conditions. The epitaxial growth of α‐Al2O3 films on single‐crystal Nb films at ∼500 °C by the MLE method is also confirmed for the first time.
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.65.-b Surface treatments

Magnetic resonance, digital image analysis, and permeability of porous media

Christian Straley, Abigail Matteson, Sechao Feng, Lawrence M. Schwartz, William E. Kenyon, and Jayanth R. Banavar

Appl. Phys. Lett. 51, 1146 (1987); http://dx.doi.org/10.1063/1.98766 (3 pages) | Cited 33 times

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The results of an experimental and theoretical study of consolidated, acid‐cleaned fused glass beads are presented. Measurements of the spin‐lattice lifetime, permeability, and capillary pressure curves in conjunction with digital analysis of scanning electron microscope images and theoretical modeling lead to a description of this porous material consistent with the fast diffusion picture of nuclear magnetic relaxation.
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76.60.-k Nuclear magnetic resonance and relaxation
47.56.+r Flows through porous media
42.30.Va Image forming and processing

Photon‐controlled oxidation of silicon

F. Micheli and Ian W. Boyd

Appl. Phys. Lett. 51, 1149 (1987); http://dx.doi.org/10.1063/1.98767 (3 pages) | Cited 10 times

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A cw argon laser was used to oxidize crystalline silicon in dry oxygen. Under otherwise identical conditions, two visible wavelengths were used to identify possible nonthermal contributions to the reaction. With a simple technique to amplify small differences in the growth rate we have confirmed that the reaction is primarily thermally controlled and that there is a photonic enhancement to Si oxidation. A simulation has also provided some initial quantitative evaluation of the process.
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81.65.-b Surface treatments
82.50.-m Photochemistry

Imaging of deep level domains in semi‐insulating GaAs by voltage contrast

D. A. Johnson, S. Myhajlenko, J. L. Edwards, G. N. Maracas, R. J. Roedel, and H. Goronkin

Appl. Phys. Lett. 51, 1152 (1987); http://dx.doi.org/10.1063/1.98768 (3 pages) | Cited 8 times

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We have used the voltage contrast effect to image deep level domains in semi‐insulating (SI) GaAs n‐i‐n resistor structures. Our samples consisted of SI, undoped, liquid encapsulated Czochralski material with alloyed AuGe/Ni contacts at spacings from 1.3 to 2.27 mm. By viewing the contact side of the samples with a scanning electron microscope while the devices were biased in the oscillation region, we observed domain formation and motion from cathode to anode in real time. Long range potentials in the GaAs were observed by viewing the polished back surface of the samples. That is, the domains which are launched from the front contacts were clearly evident in voltage contrast measurements on the back of the sample. Also, because of the nonuniform charging of the semiconductor surface by the electron beam, we observed interactions between the propagating domains and the cellular dislocation structure in the SI GaAs.
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71.55.Ht Other nonmetals
61.72.S- Impurities in crystals

Identification of a bistable defect in silicon: The carbon interstitial‐carbon substitutional pair

L. W. Song, B. W. Benson, and G. D. Watkins

Appl. Phys. Lett. 51, 1155 (1987); http://dx.doi.org/10.1063/1.98717 (3 pages) | Cited 41 times

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By using a combination of deep level transient spectroscopy (DLTS) and electron paramagnetic resonance techniques applied to samples of varying compositions, we identify the bistable defect at Ec −0.17 eV in irradiated n‐type silicon as a carbon interstitial‐carbon substitutional pair. It arises upon annealing of interstitial carbon, which is also the precursor to a remarkable recently discovered four‐level multistable defect which we now tentatively identify as a carbon‐phosphorus pair. We demonstrate a new simple method for distinguishing the bistable carbon‐carbon pair defect from the oxygen‐vacancy pair under the same DLTS peak.
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61.72.jd Vacancies
61.72.jj Interstitials
61.80.Fe Electron and positron radiation effects
71.55.Ht Other nonmetals

Rapid annealing of Hg1−xCdxTe by immersion in a hot mercury bath

R. Kalish, R. Fastow, V. Richter, and M. Shaanan

Appl. Phys. Lett. 51, 1158 (1987); http://dx.doi.org/10.1063/1.98718 (3 pages) | Cited 3 times

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A simple technique for annealing ion implanted Hg1−xCdxTe in a mercury atmosphere has been developed. In this technique, Hg1−xCdxTe is sandwiched between two silicon wafers and immersed in a hot mercury bath. This permits rapid annealing at well defined temperatures and times. Indium‐implanted Hg1−xCdxTe (x=0.23 and x=0.7) samples have been annealed using this method at temperatures ranging from 260 to 350 °C and for times ranging from 3 s to 1 h. The near surface crystalline quality, as measured by ion channeling, improved after annealing and was comparable to that obtained by other annealing techniques. No change in surface stoichiometry, as measured by particle‐induced x‐ray emission, was detected in the Hg0.77Cd0.23Te samples.
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81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization
61.72.U- Doping and impurity implantation
61.66.Fn Inorganic compounds
68.35.Dv Composition, segregation; defects and impurities

Dual implantation of Be+ and F+ in GaAs and AlxGa1−xAs

Sadao Adachi

Appl. Phys. Lett. 51, 1161 (1987); http://dx.doi.org/10.1063/1.98719 (3 pages) | Cited 16 times

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Dual implantation of Be+/F+ ions in GaAs and Al0.3Ga0.7As is performed and studied by means of Hall‐effect and secondary ion mass spectrometry analyses. This technique leads to significantly less redistribution of Be implants both in GaAs and Al0.3Ga0.7As and considerably high electrical activity in Al0.3Ga0.7As, as compared with implant of Be+ only. This technique may have the great advantage of being used to fabricate a wide variety of AlxGa1−xAs/GaAs devices.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
73.61.Ey III-V semiconductors

Performance characteristics of InGaAs/GaAs and GaAs/InGaAlAs coherently strained superlattice photodiodes

Utpal Das, Yousef Zebda, Pallab Bhattacharya, and Albert Chin

Appl. Phys. Lett. 51, 1164 (1987); http://dx.doi.org/10.1063/1.98720 (3 pages) | Cited 4 times

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The properties of In0.24Ga0.76As/GaAs and GaAs/In0.05Ga0.58Al0.37As superlattice photodiodes grown by molecular beam epitaxy have been investigated. From the temporal response characteristics, deconvolved rise times ∼60–100 ps are obtained. The measured responsivities of the photodiodes with dark currents of 5–10 nA at 10 V are ∼0.4 A/W, which correspond to peak external quantum efficiencies of ∼60%. These results indicate that very high performance photodiodes can be realized with strained layers.
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85.60.Dw Photodiodes; phototransistors; photoresistors
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors

Influence of microstructure on the Urbach edge of amorphous SiC:H and amorphous SiGe:H alloys

A. H. Mahan, P. Menna, and R. Tsu

Appl. Phys. Lett. 51, 1167 (1987); http://dx.doi.org/10.1063/1.98721 (3 pages) | Cited 32 times

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Infrared measurements have been used as a means of quantifying the amount of hydrogenated amorphous silicon and amorphous silicon alloy microstructure. Using a parameter obtained from these infrared measurements, the Urbach edge of amorphous silicon (a‐Si:H), amorphous silicon carbon (a‐SiC:H), and amorphous silicon germanium (a‐SiGe:H) obtained from photothermal deflection spectroscopy measurements fall on the same curve. This suggests that the decreasing steepness of the Urbach edge, observed to occur with increasing alloying, is due primarily to microstructural effects and not to increased structural or compositional disorder. Based upon this correlation, we suggest an explanation for the observed decrease in alloy material photoconductivity with increasing alloy content.
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81.40.Rs Electrical and magnetic properties related to treatment conditions
84.60.Jt Photoelectric conversion
72.40.+w Photoconduction and photovoltaic effects
61.43.Fs Glasses
61.43.-j Disordered solids

Selectively δ‐doped AlxGa1−xAs/GaAs heterostructures with high two‐dimensional electron‐gas concentrations n2DEG≥1.5×1012 cm−2 for field‐effect transistors

E. F. Schubert, J. E. Cunningham, W. T. Tsang, and G. L. Timp

Appl. Phys. Lett. 51, 1170 (1987); http://dx.doi.org/10.1063/1.98722 (3 pages) | Cited 46 times

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The δ‐doping concept is applied to selectively doped heterostructures in the AlxGa1−xAs/GaAs material system. High two‐dimensional electron‐gas concentrations ≥1.5×1012 cm−2 are obtained at T=300 K in such selectively δ‐doped heterostructures due to (i) size quantization in the AlxGa1−xAs and (ii) localization of donor impurities within one atomic monolayer. Shubnikov–de Haas measurements yield n2DEG =1.1×1012 cm−2 at 300 mK and at a spacer thickness of 25 Å. Selectively δ‐doped heterostructure transistors (SΔDHT’s) are fabricated and have excellent characteristics due to the enhanced electron‐gas concentrations achieved. A very high transconductance of gm ≂360 mS/mm at a gate length of 1.2 μm is obtained in depletion‐mode SΔDHT’s at T=300 K.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
85.30.Tv Field effect devices
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
73.61.Ey III-V semiconductors

Reflection high‐energy electron diffraction intensity oscillation study of InGaAs and InAlAs on InP: Application to pseudomorphic heterostructures

J.‐L. Lievin and C. G. Fonstad

Appl. Phys. Lett. 51, 1173 (1987); http://dx.doi.org/10.1063/1.98723 (3 pages) | Cited 24 times

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This letter reports the first reflection high‐energy electron diffraction intensity oscillation study of strained, pseudomorphic In1−xGaxAs and In1−yAlyAs grown by molecular beam epitaxy on InP substrates. Strain‐induced effects are studied over a broad range (up to 3%) of positive and negative mismatch. During mismatched growth, an abnormal damping of the oscillation intensity is seen which leads to the identification of a threshold thickness above which monolayer by monolayer growth no longer occurs during uninterrupted growth. This thickness is about a factor of 5 smaller than recently calculated and measured values of the critical thickness at which dislocations appear. This observation is believed to have important implications for the growth of pseudomorphic devices.
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68.55.-a Thin film structure and morphology
61.05.jh Low-energy electron diffraction (LEED) and reflection high-energy electron diffraction (RHEED)
68.35.B- Structure of clean surfaces (and surface reconstruction)
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Interface structure and lattice mismatch of epitaxial CoSi2 on Si(111)

J. Zegenhagen, K.‐G. Huang, B. D. Hunt, and L. J. Schowalter

Appl. Phys. Lett. 51, 1176 (1987); http://dx.doi.org/10.1063/1.98724 (3 pages) | Cited 33 times

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We have used the x‐ray standing‐wave technique and bulk x‐ray diffraction to investigate the structural properties of thin CoSi2 layers grown epitaxially on Si(111). The perpendicular lattice mismatch with respect to the Si substrate was found to be −0.0152±0.0003 and −0.016±0.001 for 6‐nm‐thick and 16‐nm‐thick layers, respectively. The distance between Si(111) and the first Co layer was measured to be (0.288±0.005) nm and is thus stretched by (0.014±0.005) nm compared with a value determined by Si‐like bulk bond length. The Co atoms are attached to the Si(111) dangling bonds in agreement with the model of fivefold coordinated metal atoms at the interface.
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68.35.B- Structure of clean surfaces (and surface reconstruction)
68.55.-a Thin film structure and morphology

Electronic properties of sol‐gel‐derived oxides on silicon

R. A. Weimer, P. M. Lenahan, T. A. Marchione, and C. J. Brinker

Appl. Phys. Lett. 51, 1179 (1987); http://dx.doi.org/10.1063/1.98725 (3 pages) | Cited 15 times

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Sol‐gel‐derived SiO2, borosilicate, and aluminosilicate thin films deposited on silicon and heated for 5 min at temperatures of 1000 °C or lower exhibit dielectric strength as great as 5 MV/cm and interface state densities as low as ∼1×1011/cm2 eV. These values represent significant improvements over previous sol‐gel‐derived oxides on semiconductors and indicate that sol‐gel processing can provide device quality oxides in situations where native oxides are unavailable or exhibit poor dielectric behavior, e.g., amorphous, hydrogenated silicon or III‐V compound semiconductors.
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73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
77.22.Jp Dielectric breakdown and space-charge effects
73.20.Hb Impurity and defect levels; energy states of adsorbed species
73.61.Ng Insulators

Defect annihilation in shallow p+ junctions using titanium silicide

D. S. Wen, P. L. Smith, C. M. Osburn, and G. A. Rozgonyi

Appl. Phys. Lett. 51, 1182 (1987); http://dx.doi.org/10.1063/1.98726 (3 pages) | Cited 60 times

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The residual extended defects due to end‐of‐range ion implantation damage can be totally eliminated by Ti silicidation. Shallow p+ junctions were formed by amorphizing the silicon with Ge implantation (85 keV, 1×1015 cm−2) prior to implanting boron (85 keV, 1×1015 cm−2), recrystallizing the amorphous region at 550 °C, and then rapid thermal annealing at 1050 °C for 10 s. A buried sheet of interstitial dislocation loops lying below the surface remained. However, following a self‐aligned Ti silicide process, the end‐of‐range defects due to Ge ion implantation damage were no longer observed in cross‐sectional transmission electron micrographs. The annihilation of these end‐of‐range interstitial dislocation loops is attributed to the injection of vacancies during Ti silicidation.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.80.Jh Ion radiation effects

New photoluminescence defect at 1.0192 eV in silicon molecular beam epitaxy layers ascribed to Cu

R. Sauer, M. Asom, R. People, D. V. Lang, L. C. Kimerling, and J. C. Bean

Appl. Phys. Lett. 51, 1185 (1987); http://dx.doi.org/10.1063/1.98727 (3 pages) | Cited 3 times

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We report a new photoluminescence defect spectrum with a no‐phonon transition at 1.0192 eV which emerges in many silicon layers grown on silicon substrates by molecular beam epitaxy. Comparison of the no‐phonon transition and the chief local mode (ℏω=7.5 meV) to the well‐established Cu‐related spectrum at 1.0145 eV suggests that the new defect incorporates Cu as well. Deep level transient measurements support the presence of Cu in the epilayers. We suggest that this defect spectrum has recently been observed by others but was not identified and associated with Cu.
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78.55.Hx Other solid inorganic materials
71.55.Ht Other nonmetals
71.35.-y Excitons and related phenomena

Characterization of GaAs grown by metalorganic chemical vapor deposition on Si‐on‐insulator

S. J. Pearton, S. M. Vernon, K. T. Short, J. M. Brown, C. R. Abernathy, R. Caruso, S. N. G. Chu, V. E. Haven, and S. N. Bunker

Appl. Phys. Lett. 51, 1188 (1987); http://dx.doi.org/10.1063/1.98728 (3 pages) | Cited 6 times

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Epitaxial GaAs layers were grown by metalorganic chemical vapor deposition on Si‐on‐insulator structures formed by high dose oxygen implantation. The quality of the GaAs films was examined as a function of layer thickness (0.01–4 μm). The surface morphology, ion backscattering yield, x‐ray diffraction peak width, and Si implant activation efficiency all improve substantially with GaAs thickness. At a film thickness of 4 μm many of these properties are comparable to bulk GaAs, but some cracking of the epitaxial film is evident. Cross‐sectional transmission electron microscopy reveals an average defect density of ∼108 cm−2 in the GaAs layer, which is similar to the density in GaAs films grown directly on Si.
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68.55.-a Thin film structure and morphology
72.80.Ey III-V and II-VI semiconductors
73.61.Ey III-V semiconductors
73.40.Ty Semiconductor-insulator-semiconductor structures

Growth of high Tc superconducting thin films using molecular beam epitaxy techniques

C. Webb, S.‐L. Weng, J. N. Eckstein, N. Missert, K. Char, D. G. Schlom, E. S. Hellman, M. R. Beasley, A. Kapitulnik, and J. S. Harris

Appl. Phys. Lett. 51, 1191 (1987); http://dx.doi.org/10.1063/1.98729 (3 pages) | Cited 55 times

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Thin films of the high‐temperature superconductor DyBa2Cu3O7−x have been grown on SrTiO3 substrates using molecular beam epitaxy techniques. Reflection high‐energy electron diffraction patterns observed during deposition indicate incomplete oxidation of copper and growth of oriented metallic copper microcrystals in a matrix of amorphous barium and dysprosium oxides. After post‐growth anneal the films exhibited sharp superconducting transitions with zero resistance observed as high as 89 K and critical current densities of 4.8×105 A/cm2 at 4.2 K and 3.9×104 A/cm2 at 77 K.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
74.78.-w Superconducting films and low-dimensional structures
74.70.-b Superconducting materials other than cuprates
81.40.Rs Electrical and magnetic properties related to treatment conditions

Preparation of Y‐Ba‐Cu‐O thin films on MgO by dc magnetron sputtering from a stoichiometric Y1Ba2Cu3O7−δ target

S. J. Lee, E. D. Rippert, B. Y. Jin, S. N. Song, S. J. Hwu, K. Poeppelmeier, and J. B. Ketterson

Appl. Phys. Lett. 51, 1194 (1987); http://dx.doi.org/10.1063/1.98730 (3 pages) | Cited 21 times

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Y‐Ba‐Cu‐O thin films have been deposited on MgO substrates by dc magnetron sputtering from a stoichiometric YBa2Cu3O7−δ target, after which they are subjected to a short heat treatment. Zero resistance is routinely achieved near 60 K, and one film shows zero resistance at 68.0 K.
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81.15.Cd Deposition by sputtering
74.78.-w Superconducting films and low-dimensional structures
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
74.70.-b Superconducting materials other than cuprates

Hybrid aligned cholesteric: A novel liquid‐crystal alignment

M. R. Lewis and M. C. K. Wiltshire

Appl. Phys. Lett. 51, 1197 (1987); http://dx.doi.org/10.1063/1.98731 (3 pages) | Cited 3 times

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A hybrid aligned cholesteric (HAC) liquid‐crystal (LC) structure is reported. The LC director tilt varies from a small angle at one surface to almost 90° at the other, while incorporating a helical twist. Cells having one surface treated with rubbed polyvinyl alcohol and the other with the organosilane octadecyltriethoxysilane, adopt the HAC structure when filled with a long pitch chiral mixture. The presence of the HAC structure was confirmed by studies of the variation of the optical rotation, first with thickness in a wedge cell and second with temperature for a compensated cholesteric mixture. Use of the HAC structure in a wedge cell is characterized by an absence of the pitch breaks seen with conventional alignments.
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61.30.Eb Experimental determinations of smectic, nematic, cholesteric, and other structures
78.20.Ek Optical activity
61.30.Gd Orientational order of liquid crystals; electric and magnetic field effects on order

Monolithic integration of an AlGaAs/GaAs multiple quantum well distributed feedback laser and a grating coupler for surface emission

Susumu Noda, Keisuke Kojima, Kazumasa Mitsunaga, Kazuo Kyuma, Koich Hamanaka, and Takashi Nakayama

Appl. Phys. Lett. 51, 1200 (1987); http://dx.doi.org/10.1063/1.98732 (3 pages) | Cited 6 times

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Monolithically integrated surface‐emitting device consisting of an AlGaAs/GaAs multiple quantum well distributed feedback laser and a grating coupler is demonstrated for the first time. The grating coupler was made by utilizing the properties of low loss and easily saturable absorption in the multiple quantum well structure. No additional crystal growths or complicated fabrication processes were required for the integration. An output power of 2 mW and a narrow beam divergence of 0.22° were obtained under continuous wave operation.
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42.82.-m Integrated optics
42.55.Px Semiconductor lasers; laser diodes
42.79.Dj Gratings
42.79.Gn Optical waveguides and couplers
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