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16 Aug 1993

Volume 63, Issue 7, pp. 857-1010

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Room temperature ZnSe/ZnCdSe bistable self‐electro‐optic effect device operating at 488 nm

S. Y. Wang, G. Horsburgh, P. Thompson, I. Hauksson, J. T. Mullins, K. A. Prior, and B. C. Cavenett

Appl. Phys. Lett. 63, 857 (1993); http://dx.doi.org/10.1063/1.109880 (3 pages) | Cited 11 times

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Optical bistability at room temperature has been observed for the first time in a II‐VI semiconductor self‐electro‐optic effect device fabricated by molecular beam epitaxy. The optical switch is based on a ZnSe/ZnCdSe multiple quantum well structure situated within a p‐n junction and the devices operate at 488 nm in the blue‐green spectral region.
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42.65.Pc Optical bistability, multistability, and switching, including local field effects
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks
78.66.Hf II-VI semiconductors

Demonstration of demultiplexing with a rocking filter fiber

C. G. Krautschik, P. Wigley, G. I. Stegeman, and R. H. Stolen

Appl. Phys. Lett. 63, 860 (1993); http://dx.doi.org/10.1063/1.109881 (3 pages) | Cited 2 times

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We show that the presence of a strong pump beam detuned from the center wavelength of a rocking filter fiber causes a signal beam at the filter resonance frequency to switch between polarization states. This process is used to switch out a pulse from a pulse train.
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42.81.Wg Other fiber-optical devices
42.65.Pc Optical bistability, multistability, and switching, including local field effects

Study of the effects of aging on the relaxation luminance in atomic layer epitaxy ZnS:Mn alternating‐current thin‐film electroluminescent devices

D. C. Morton, J. Koh, C. P. Hogh, and R. Khormaei

Appl. Phys. Lett. 63, 863 (1993); http://dx.doi.org/10.1063/1.109882 (3 pages) | Cited 5 times

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A study of the relaxation luminance peak and the electro‐optical aging effects in atomic layer epitaxy (ALE) normally doped ZnS:Mn alternating‐current thin‐film electroluminescent (ACTFEL) devices is presented. The relaxation luminance occurs when the applied voltage goes to zero. The changes in the luminance versus time L(t), current versus time I(t), and characteristics of luminance versus voltage, as a function of aging are discussed in terms of a model which includes bulk traps, space charge, and shallow trap levels. This relaxation luminance peak observed in ALE devices provides a means of gaining insight into ACTFEL devices.
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85.60.Jb Light-emitting devices
73.40.Sx Metal-semiconductor-metal structures
78.60.Fi Electroluminescence

All‐optical bistable switching and signal regeneration in a semiconductor layered distributed‐feedback/Fabry–Perot structure

J. He, M. Cada, M.‐A. Dupertuis, D. Martin, F. Morier‐Genoud, C. Rolland, and A. J. SpringThorpe

Appl. Phys. Lett. 63, 866 (1993); http://dx.doi.org/10.1063/1.109883 (3 pages) | Cited 21 times

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We report the experimental observation of optical bistable switching in a combined distributed‐feedback/Fabry–Perot structure. The sample had a high switching contrast with almost zero reflectivity in the on‐state. A turnoff time as short as 4 ns was measured. The threshold power for bistability was about 2 mW. Bistable switching with the memory effect and a potential application for all‐optical signal regeneration were demonstrated.
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42.65.Pc Optical bistability, multistability, and switching, including local field effects
78.66.Fd III-V semiconductors
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks

Electrochromic properties of niobium oxide thin films prepared by radio‐frequency magnetron sputtering method

Toshiro Maruyama and Susumu Arai

Appl. Phys. Lett. 63, 869 (1993); http://dx.doi.org/10.1063/1.109884 (2 pages) | Cited 15 times

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Electrochromic niobium oxide thin films were prepared by a radio‐frequency magnetron sputtering method. Amorphous Nb2O5 thin films deposited at radio‐frequency power 100 W showed the electrochromic behavior: Reduction and oxidation of the films in 0.1 M Na2CO3+0.1 M NaHCO3 buffer solution resulted in coloration and bleaching, respectively. Coulometry indicated that the coloration efficiency was 10 cm2/C.  
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78.66.Nk Insulators
82.45.-h Electrochemistry and electrophoresis
81.15.Cd Deposition by sputtering

Measurement of femtosecond electron bunches from metal photocathodes

T. Tsang

Appl. Phys. Lett. 63, 871 (1993); http://dx.doi.org/10.1063/1.109885 (3 pages) | Cited 4 times

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A technique of direct generation and detection of femtosecond electron bunches is reported. These electrons pulses are measured with high accuracy using nonlinear photoemission. In this initial demonstration, n=1 and higher‐order femtosecond optical soliton pulses are used to liberate electrons from metals.
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79.20.Ds Laser-beam impact phenomena
79.60.-i Photoemission and photoelectron spectra
41.75.Fr Electron and positron beams

Electronic beam induced poling of BaTiO3 thin films

H. A. Lu, L. A. Wills, B. W. Wessels, W. P. Lin, and G. K. Wong

Appl. Phys. Lett. 63, 874 (1993); http://dx.doi.org/10.1063/1.109886 (3 pages) | Cited 2 times

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The effect of electron beam irradiation on second harmonic generation of BaTiO3 thin films was studied. Enhanced second harmonic intensity was measured from BaTiO3 thin films irradiated by electron beams of 10, 15, and 25 keV using a scanning electron microscope. The enhancement of the second harmonic generations is attributed to the electron beam‐induced poling of the film. The effectiveness of the electron beam irradiation on second harmonic generation enhancement is comparable to that of the corona poling of the film at room temperature. This electron beam induced poling technique offers a promising method for nonlinear optical device fabrication.
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42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
61.80.Fe Electron and positron radiation effects
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates

High‐efficiency pyrromethene doped solid‐state dye lasers

Robert E. Hermes, Toomas H. Allik, Suresh Chandra, and J. Andrew Hutchinson

Appl. Phys. Lett. 63, 877 (1993); http://dx.doi.org/10.1063/1.109887 (3 pages) | Cited 87 times

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Successful laser oscillation of various pyrromethene dyes doped in a modified acrylic plastic has been achieved. Pumped with a frequency doubled Nd:YAG laser at 532 nm, a slope efficiency of 85% has been obtained from one of the dyes in plastic, with an output beam energy of 128 mJ. A useful lifetime of greater than 20 000 shots at 3.33 Hz with output energies above 30 mJ has been demonstrated, with only a 34% loss in the available output energy.
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42.55.Mv Dye lasers
42.55.Rz Doped-insulator lasers and other solid state lasers
42.60.-v Laser optical systems: design and operation
42.70.Jk Polymers and organics

Photonic integrated tunable receivers with optical preamplifiers for direct detection

Z. M. Chuang, M. J. Mondry, D. B. Young, D. A. Cohen, and L. A. Coldren

Appl. Phys. Lett. 63, 880 (1993); http://dx.doi.org/10.1063/1.109888 (3 pages) | Cited 9 times

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We propose and demonstrate a photonic integrated tunable receiver which cascades a traveling‐wave optical preamplifier, a passive tunable grating‐assisted codirectional coupler filter, and a waveguide photodetector. The devices contain three strained InGaAs quantum wells and operate around λ=0.98 μm. The spectral responses have been measured using the broadband spontaneous emission from the integrated amplifier. Optical filters ∼4‐nm wide, ∼10‐nm apart with grating pitches ranging from 7.4 to 10.6 μm were observed. Wavelength selective photodetection of a channel ∼3‐nm wide, tunable over 4.3 nm with a reverse bias is in relatively good agreement with theory.
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42.79.Pw Imaging detectors and sensors
42.79.Sz Optical communication systems, multiplexers, and demultiplexers
42.82.-m Integrated optics
85.60.Gz Photodetectors (including infrared and CCD detectors)

Polymer optical fiber amplifier

A. Tagaya, Y. Koike, T. Kinoshita, E. Nihei, T. Yamamoto, and K. Sasaki

Appl. Phys. Lett. 63, 883 (1993); http://dx.doi.org/10.1063/1.109889 (2 pages) | Cited 34 times

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Polymer optical fiber amplifiers (POFA) of graded‐index (GI) type, which have a gain in visible region, were successfully prepared by the interfacial‐gel polymerization technique. The gain of 27 dB was observed at 591 nm signal wavelength with 690 W launched pump power at 532 nm in a GI POFA with 0.5 m length.
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42.81.Ht Gradient-index (GRIN) fiber devices
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.70.Jk Polymers and organics

Relationship among reflectance‐difference spectroscopy, surface photoabsorption, and spectroellipsometry

K. Hingerl, D. E. Aspnes, I. Kamiya, and L. T. Florez

Appl. Phys. Lett. 63, 885 (1993); http://dx.doi.org/10.1063/1.109890 (3 pages) | Cited 40 times

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From the reflectance expressions for a thin biaxial layer on an isotropic substrate we relate reflectance‐difference spectroscopy (RDS), surface photoabsorption (SPA), and spectroellipsometry. Using these results and our recently acquired RD database, we determine surface reconstructions present during flow‐modulated organometallic chemical vapor growth of epitaxial GaAs from SPA data that were published by others.
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68.55.-a Thin film structure and morphology
78.66.Fd III-V semiconductors

Resonant holographic interferometry of laser‐ablation plumes

R. A. Lindley, R. M. Gilgenbach, and C. H. Ching

Appl. Phys. Lett. 63, 888 (1993); http://dx.doi.org/10.1063/1.109891 (3 pages) | Cited 14 times

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Two‐dimensional species‐resolved, holographic interferometry has been used to measure absolute‐line‐density profiles of KrF laser ablation plumes in vacuum and gas. Laser ablation plumes are generated by focusing a KrF excimer laser (40 ns, 248 nm, ≤0.8 J) on a solid aluminum target at a fluence of 2–5 J/cm2. Aluminum neutral absolute‐line‐density profiles are measured to characterize the interaction of ablated material with background gases versus vacuum. The interferograms are made using a 20 ns pulsed dye laser tuned near (≤±0.020 nm) the 394.401 nm aluminum neutral transition from the ground state. Calculations have been performed to obtain absolute‐line‐density profiles from the resonant fringe shift data. Peak aluminum neutral line densities of up to 1×1015 cm−2 have been measured for plumes in backgrounds of 14 mTorr and 1 Torr argon and in vacuum.
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52.50.Jm Plasma production and heating by laser beams (laser-foil, laser-cluster, etc.)
52.70.Nc Particle measurements
79.20.Ds Laser-beam impact phenomena

Atomic force microscope investigation of C60 adsorbed on silicon and mica

T. Thundat, R. J. Warmack, D. Ding, and R. N. Compton

Appl. Phys. Lett. 63, 891 (1993); http://dx.doi.org/10.1063/1.109892 (3 pages) | Cited 26 times

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The morphological and frictional characteristics of C60 adsorbed on silicon and mica surfaces have been investigated using atomic force microscopy (AFM). Deposition of fullerenes by vacuum sublimation results in uniform coverage of microcrystallites with an average size between 40 and 60 nm. Small area scans on the top of these microcrystallites show disordered arrangements of molecules. Frictional measurements carried out monitoring buckling of the AFM cantilever show increased friction for C60‐covered surfaces over that of clean substrates. At sufficiently high forces, the film was selectively displaced by the AFM tip, so that fine patterns could be drawn on fullerene‐covered surfaces.
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68.60.Bs Mechanical and acoustical properties
68.55.-a Thin film structure and morphology
68.37.Ef Scanning tunneling microscopy (including chemistry induced with STM)
68.37.Ps Atomic force microscopy (AFM)
68.37.Rt Magnetic force microscopy (MFM)
68.37.Uv Near-field scanning microscopy and spectroscopy
61.46.-w Structure of nanoscale materials

Ultraviolet dosimetric properties of α‐Al2O3 crystals

R. Pérez Salas, R. Aceves, R. Meléndrez, M. Barboza‐Flores, and L. P. Pashchenko

Appl. Phys. Lett. 63, 894 (1993); http://dx.doi.org/10.1063/1.109893 (2 pages) | Cited 3 times

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Thermoluminescence (TL) measurements were performed in crystal samples of α‐Al2O3 (TLD 500 K) subjected to UV irradiation in the range of 200–320 nm. The material is very sensitive to UV light and can be considered potentially useful for actinic region dosimetry. The TL glow curve is composed of two glow peaks centered at 58 and 184 °C, respectively. The TL excitation spectrum shows a maximum for 220 nm light.
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78.60.Kn Thermoluminescence
78.40.Ha Other nonmetallic inorganics
85.60.Gz Photodetectors (including infrared and CCD detectors)
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)

Damage accumulation during high‐dose, O+ implantation in Si

O. W. Holland, D. S. Zhou, and D. K. Thomas

Appl. Phys. Lett. 63, 896 (1993); http://dx.doi.org/10.1063/1.109894 (3 pages) | Cited 15 times

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High‐dose O+ implantation of Si between 450 and 500 keV is investigated to better understand the mechanisms responsible for ion‐induced growth of damage, especially in the top Si layer ahead of the region where a buried oxide forms. Two distinct states are identified in this Si layer over an extended range of fluence (≥1018 cm−2): a low‐density defect state and a high‐density one. These states are observed at all irradiation temperatures, including ambient temperature. The transition between the states is rather abrupt with the onset at a high fluence, which decreases with decreasing temperature. The existence of the low‐density state offers a possibility of forming dislocation‐free silicon‐on‐insulator wafers, even for ambient temperature irradiations. A processing method for achieving such wafers is discussed.
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61.80.Jh Ion radiation effects
61.72.uf Ge and Si

Iodine doping in mercury cadmium telluride (Hg1−xCdxTe) grown by direct alloy growth using metalorganic chemical vapor deposition

S. Murakami, T. Okamoto, K. Maruyama, and H. Takigawa

Appl. Phys. Lett. 63, 899 (1993); http://dx.doi.org/10.1063/1.109895 (3 pages) | Cited 10 times

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We investigated iodine doping in mercury cadmium telluride (Hg1−xCdxTe) grown by direct alloy growth using metalorganic chemical vapor deposition, with isopropyl‐iodine (IPI) as the dopant source. The memory effect in iodine doping is much smaller than that in indium doping. We confirmed by secondary ion mass spectroscopy (SIMS) measurement that sharp dopant transitions (0.2 μm/decade) were obtained by switching off the IPI during growth. The electron concentration at 77 K was linearly proportional to the dopant partial pressure from 5×1015 to 2×1018 cm−3. We confirmed by SIMS that 20%–100% of the iodine was active as a donor. The Hall coefficient shows classical n‐type extrinsic behavior from 20 to 300 K. The electron mobility was as high as that in an indium‐doped sample. The layer with a Cd fraction of x=0.23, doped to 5×1016 cm−3, exhibited a mobility of 4.7×104 cm2/V s at 77 K and 6.9×104 cm2/V s at 20 K. The iodine in the HgCdTe layers was thermally stable. We found no variation in the electrical properties and the iodine depth profile after annealing at 400 °C for 2 h.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Strong room‐temperature photoluminescence of hydrogenated amorphous silicon oxide and its correlation to porous silicon

Chi‐Huei Lin, Si‐Chen Lee, and Yang‐Fang Chen

Appl. Phys. Lett. 63, 902 (1993); http://dx.doi.org/10.1063/1.109867 (3 pages) | Cited 24 times

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A set of hydrogenated amorphous silicon oxide (a‐SiOx:H) films have been fabricated by plasma enhanced chemical vapor deposition. Some of the films exhibit strong room‐temperature photoluminescence and others do so only after annealing at high temperature. The variation of photoluminescence after different annealing treatments for these films is found to be similar to that of porous silicon. Assisted by infrared spectra it is concluded that the photoluminescence from a‐SiOx:H is originated from the small a‐Si clusters or microcrystalline silicon embedded in the amorphous SiOx network. This argument may support a similar model proposed to explain the visible photoluminescence of porous silicon.
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78.55.Hx Other solid inorganic materials

Fabrication and Raman scattering studies of one‐dimensional nanometer structures in (110) silicon

An‐Shyang Chu, Saleem H. Zaidi, and S. R. J. Brueck

Appl. Phys. Lett. 63, 905 (1993); http://dx.doi.org/10.1063/1.109868 (3 pages) | Cited 16 times

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A simple technique for fabricating large fields of uniform nm scale Si structures is reported. This technique makes use of the highly anisotropic etching rates of KOH:H2O solution (40 wt. %) in Si (400:200:1=〈110〉:〈100〉:〈111〉). A large field of uniform sub‐μm thick walls, along the 〈112〉 direction, is generated on a (110) Si sample coated with Si3N4 and photoresist films, by standard interferometric lithography techniques. The developed photoresist grating pattern is transferred into the Si3N4 layer by isotropic CF4 plasma etching. Finally, the nitride layer serves as an etch mask for the anisotropic chemical etch. Arrays of Si walls with pitch of 0.34 μm, sharp (110)–{111} corners, depths of 2.0 μm, and wall widths below SEM resolution limits are reported. The Raman scattering spectra of these structures shows shifted, asymmetrical line shapes; simple model calculations based on size‐effect‐induced relaxation of the usual Δk=0 momentum selection rule provide estimated wallwidths≤10 nm.
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81.07.-b Nanoscale materials and structures: fabrication and characterization
81.16.-c Methods of micro- and nanofabrication and processing
85.35.-p Nanoelectronic devices
85.40.Hp Lithography, masks and pattern transfer

Low dark current infrared hot‐electron transistor for 77 K operation

K. K. Choi, M. Z. Tidrow, M. Taysing‐Lara, W. H. Chang, C. H. Kuan, C. W. Farley, and F. Chang

Appl. Phys. Lett. 63, 908 (1993); http://dx.doi.org/10.1063/1.109869 (3 pages) | Cited 19 times

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Recently, thermal imaging using quantum well infrared photodetector (QWIP) focal plane arrays has been demonstrated. However, the operating temperature needs to be kept around 60 K due to the large dark current occurring at higher temperatures. In order to achieve thermal imaging at 77 K, we have designed and demonstrated two infrared hot‐electron transistor structures, whose dark current is two to three orders of magnitude lower than that of a QWIP. The resultant dark current falls within the limit of the charge handling capacity of a readout circuit, and the infrared detection is demonstrated to be background limited at 77 K. The noise equivalent temperature difference of the detectors is estimated to be 14 and 26 mK, respectively.
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85.60.Gz Photodetectors (including infrared and CCD detectors)
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
78.66.Fd III-V semiconductors
72.40.+w Photoconduction and photovoltaic effects

Nonalloyed ohmic contacts to n‐Si using a strained Si0.50Ge0.50 buffer layer

Hsing‐Kuen Liou, Edward S. Yang, and K. N. Tu

Appl. Phys. Lett. 63, 911 (1993); http://dx.doi.org/10.1063/1.109842 (3 pages) | Cited 3 times

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We have grown an 80‐Å‐thick strained Si0.50Ge0.50 layer on n‐Si by molecular‐beam epitaxy. The strained layer is used to lower the Schottky barrier height for making a nonalloyed shallow ohmic contact to the n‐Si. X‐ray photoelectron spectroscopy was employed to investigate the Si 2p and Ge 3d core‐level binding energies of the strained and the relaxed Si0.50Ge0.50 and to determine their relative Fermi‐level positions. Rutherford backscattering and Auger depth profiling were employed to determine the contact reactions using Ti, W, or Pt as contact metals. In the case of Pt, a 500‐Å W diffusion barrier can protect the ohmic behavior up to 550 °C for 30 min. The specific contact resistance of the metal/Si0.50Ge0.50/n‐Si contact extracted from the D‐type cross‐bridge Kelvin resistor was 3.5×10−5 Ω cm2.
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73.40.Cg Contact resistance, contact potential
73.30.+y Surface double layers, Schottky barriers, and work functions
73.40.Ns Metal-nonmetal contacts

Effects of propane and methane on carbonization and surface morphology in heteroepitaxial growth of β‐SiC films on (100) Si via chemical vapor deposition

B. Bahavar, M. I. Chaudhry, and R. J. McCluskey

Appl. Phys. Lett. 63, 914 (1993); http://dx.doi.org/10.1063/1.109843 (3 pages) | Cited 6 times

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Epitaxial β‐SiC films have been produced on Si(100) substrates by chemical vapor deposition (CVD) with 90% of the carbon supplied by methane and 10% by propane as compared to 100% by propane (or 100% by any carbon source more reactive than methane). These films, grown at 1350 °C in a CVD reactor, are single crystalline with a three‐dimensional surface morphology and have similar growth rates but lower carrier concentrations than films grown from propane and silane. The interplay of the chemistry of methane and evaporative loss of the Si substrate at ∼1100–1300 °C provide a reasonable explanation of our observations.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.-a Thin film structure and morphology

Cavity design for improved electrical injection in InAlGaP/AlGaAs visible (639–661 nm) vertical‐cavity surface‐emitting laser diodes

R. P. Schneider and J. A. Lott

Appl. Phys. Lett. 63, 917 (1993); http://dx.doi.org/10.1063/1.109844 (3 pages) | Cited 9 times

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A novel optical cavity design for improved electrical injection in visible vertical‐cavity surface‐emitting laser (VCSEL) diodes employing an InGaP/InAlGaP strained quantum‐well active optical cavity and AlAs/Al0.5Ga0.5As distributed Bragg reflectors (DBRs) is described. The cavity design was determined by measuring the lasing threshold current density of visible edge‐emitting laser diodes with AlAs/Al0.5Ga0.5As DBR cladding layers. By inserting InAlP spacer layers between the active region and the DBR cladding, significant improvement in the performance of the edge‐emitting lasers was achieved. This approach was then applied to the design of visible VCSEL diodes, and resulted in the first demonstration of room‐temperature electrically injected lasing, over the wavelength range 639–661 nm. The visible VCSELs, with a diameter of 20 μm, exhibit pulsed output power of 3.4 mW at 650 nm, and continue to lase at a duty cycle of 40%. The threshold current was 30 mA, with a low threshold voltage (2.7 V) and low series resistance (<15 Ω).
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42.55.Px Semiconductor lasers; laser diodes
42.60.-v Laser optical systems: design and operation

Nature of Pb‐like dangling‐orbital centers in luminescent porous silicon

F. C. Rong, J. F. Harvey, E. H. Poindexter, and G. J. Gerardi

Appl. Phys. Lett. 63, 920 (1993); http://dx.doi.org/10.1063/1.109845 (3 pages) | Cited 26 times

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The Pb‐like dangling‐orbit centers in luminescent porous silicon (LPSi) have been enhanced to very high concentration (1015 cm−2) by gentle oxidation. High signal‐to‐noise ratio and very sharp lines enable the g‐value maps, and 29Si hyperfine and superhyperfine structures to be clearly resolved by ordinary EPR. Only one Pb‐like center is observed, and it is proven to be of the Pb0 variety (⋅Si≡Si3). The relative EPR signal strengths from different g limbs indicate that the LPSi crystallite morphology is not dominated by needles or platelets.
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78.55.Hx Other solid inorganic materials
61.72.Hh Indirect evidence of dislocations and other defects (resistivity, slip, creep, strains, internal friction, EPR, NMR, etc.)
76.30.Mi Color centers and other defects

Transient velocity overshoot dynamics in GaAs for electric fields ≤ 200 kV/cm

J. Son, W. Sha, J. Kim, T. B. Norris, J. F. Whitaker, and G. A. Mourou

Appl. Phys. Lett. 63, 923 (1993); http://dx.doi.org/10.1063/1.109846 (3 pages) | Cited 20 times

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We have experimentally studied the transient velocity overshoot dynamics of photoexcited carriers in GaAs for electric fields as great as 200 kV/cm. Time domain waveforms proportional to the velocity and the acceleration of carriers have been acquired, respectively, from guided and free‐space radiating signals which contain terahertz frequency components. The measurements demonstrated that the degree of overshoot was maximized for an electric field on the GaAs between 40 and 50 kV/cm when 1.44‐eV photons in an 80‐fs laser pulse excited the sample. For carriers excited with higher initial energy (1.55 eV), the degree of overshoot decreased and the maximum degree of overshoot occurred at a higher electric field.
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72.20.Ht High-field and nonlinear effects
72.40.+w Photoconduction and photovoltaic effects
72.80.Ey III-V and II-VI semiconductors
78.47.-p Spectroscopy of solid state dynamics

Evidence for hydrogen accumulation at strained layer heterojunctions

Z. Sobiesierski and J. B. Clegg

Appl. Phys. Lett. 63, 926 (1993); http://dx.doi.org/10.1063/1.110775 (3 pages) | Cited 3 times

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The incorporation of hydrogen into strained InxGa1−xAs/GaAs quantum wells results in the formation of shallow, H‐related radiative states which compete with, and quench, the intrinsic band‐to‐band luminescence. By comparing the photoluminescence data obtained from hydrogenated material with secondary ion mass spectroscopy profiles from deuterated material, it is possible to deduce that the H‐related radiative states are associated with H which is accumulated at the well interfaces.
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78.66.Fd III-V semiconductors
78.55.Cr III-V semiconductors
71.55.Eq III-V semiconductors
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