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12 Mar 1990

Volume 56, Issue 11, pp. 987-1077

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Broader spectral width InGaAsP stacked active layer superluminescent diodes

Osamu Mikami, Hiroshi Yasaka, and Yoshio Noguchi

Appl. Phys. Lett. 56, 987 (1990); http://dx.doi.org/10.1063/1.102571 (3 pages) | Cited 18 times

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Fabrication and characteristics of broader spectral width 1.3 μm and 1.5 μm InGaAsP superluminescent diodes having a novel stacked active layer (STAC‐SLDs) structure are reported. The emission spectral width is successfully broadened as much as twice that of conventional SLDs, yielding spectral widths of 80 and 140 nm for the 1.3 μm and the 1.5 μm SLD, respectively.
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85.60.Jb Light-emitting devices
85.60.Dw Photodiodes; phototransistors; photoresistors
42.55.Px Semiconductor lasers; laser diodes
42.79.Sz Optical communication systems, multiplexers, and demultiplexers

GaAs/AlGaAs single‐mode optical waveguides with low propagation loss and strong optical confinement

M. Seto, A. Shahar, R. J. Deri, W. J. Tomlinson, and A. Yi‐Yan

Appl. Phys. Lett. 56, 990 (1990); http://dx.doi.org/10.1063/1.102572 (3 pages) | Cited 9 times

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Singe‐mode optical waveguides have been fabricated with a saturated bromine water etchant using single‐heterostructure GaAs/AlGaAs epitaxial material, with propagation losses as low as 0.6 dB/cm for 1.66 μm deeply etched ribs (Δneff≂2.4) and losses below 0.2 dB/cm for 0.23 μm shallowly etched ribs (Δneff =0.0067), measured at λ=1.5 μm.
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42.79.Gn Optical waveguides and couplers
42.82.-m Integrated optics
42.86.+b Optical workshop techniques

Ultrafast modulation with subpicosecond recovery time in a GaAs/AlGaAs nonlinear directional coupler

R. Jin, J. P. Sokoloff, P. A. Harten, C. L. Chuang, S. G. Lee, M. Warren, H. M. Gibbs, N. Peyghambarian, J. N. Polky, and G. A. Pubanz

Appl. Phys. Lett. 56, 993 (1990); http://dx.doi.org/10.1063/1.102573 (3 pages) | Cited 16 times

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All‐optical modulation is observed at room temperature in a GaAs/AlGaAs multiple quantum well nonlinear directional coupler using femtosecond pulses. The origin of the ultrafast (<500 fs) recovery of the device is attributed to the optical Stark effect.
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42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks
42.79.Gn Optical waveguides and couplers
42.65.Pc Optical bistability, multistability, and switching, including local field effects
42.65.Re Ultrafast processes; optical pulse generation and pulse compression

CO2 laser drilling of copper following excimer laser pretreatment

G. Kinsman and W. W. Duley

Appl. Phys. Lett. 56, 996 (1990); http://dx.doi.org/10.1063/1.102574 (3 pages) | Cited 3 times

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Efficient CO2 laser drilling of copper sheet has been obtained following pretreatment with excimer laser radiation at intensities of (1–2)×106 W cm−2. The present studies show a significant reduction in the laser pulse energy, pulse duration, and gas assist parameters required to drill copper sheets with thicknesses of up to 1 mm. Optimization of laser drilling under these conditions involves a material removal regime that differs from that obtained at high laser intensity when drilling untreated surfaces.
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81.90.+c Other topics in materials science (restricted to new topics in section 81)
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)

Transmission mode spatial light modulator using a B12SiO20 crystal and polymer‐dispersed liquid‐crystal layers

Kuniharu Takizawa, Hiroshi Kikuchi, Hideo Fujikake, and Masakatsu Okada

Appl. Phys. Lett. 56, 999 (1990); http://dx.doi.org/10.1063/1.102575 (3 pages) | Cited 7 times

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We describe a new type of transmission mode spatial light modulator (SLM) using a photoconductive Bi12SiO20 crystal and a polymer‐dispersed liquid crystal (PDLC) composed of microdroplets of nematic liquid crystal of nonspherical shape randomly dispersed in polymer matrix. The SLM using light scattering in the PDLC has several advantages, such as no polarizer, high transmission of readout light, video rate operation, and ease of fabrication. The device, which consists of a 20 μm PDLC and a 0.5 mm Bi12SiO20 crystal, has a limiting resolution of 30 lp/mm and a high uniformity of the readout image.
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42.79.Hp Optical processors, correlators, and modulators

Experimental determination of transparency current density and estimation of the threshold current of semiconductor quantum well lasers

T. R. Chen, L. E. Eng, Y. H. Zhuang, and A. Yariv

Appl. Phys. Lett. 56, 1002 (1990); http://dx.doi.org/10.1063/1.102598 (3 pages) | Cited 8 times

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An experimental method for determining the transparency current density of semiconductor quantum well lasers is demonstrated in a strained‐layer InGaAs/GaAs single quantum well laser system. The experimental results are then used as a practical guide to the study of ultralow threshold lasers. A threshold current as low as 0.75 mA is observed.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions

Characteristics of a Ta photocathode for the generation of picosecond x‐ray pulses

B. Van Wonterghem and P. M. Rentzepis

Appl. Phys. Lett. 56, 1005 (1990); http://dx.doi.org/10.1063/1.102599 (3 pages) | Cited 7 times

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The properties of laser‐driven tantalum photocathodes as an electron emitter for the creation of ultrashort electron bunches and x‐ray pulses are discussed. Despite the smaller quantum efficiency of metals, their inertness, damage threshold, and lifetime compare favorably with semiconductor photocathodes. Using the fourth harmonic of a Nd:YAG laser, currents of over 3 nC per pulse have been achieved which produced x‐ray pulses with a brightness of 6.2×106 Cu Kα x‐ray photons cm−2 sr−1 and a duration of 70 ps, as determined by an x‐ray streak camera.
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79.60.Bm Clean metal, semiconductor, and insulator surfaces
72.40.+w Photoconduction and photovoltaic effects
06.60.Jn High-speed techniques (microsecond to femtosecond)
07.85.-m X- and γ-ray instruments

Observation of Maker fringes and estimation of χ(3) using picosecond nondegenerate four‐wave mixing in AlGaAs waveguides

H. Q. Le, D. E. Bossi, K. B. Nichols, and W. D. Goodhue

Appl. Phys. Lett. 56, 1008 (1990); http://dx.doi.org/10.1063/1.102600 (3 pages) | Cited 2 times

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Nondegenerate four‐wave mixing experiments have been conducted in Al0.2Ga0.8As ridge waveguides, using picosecond laser pulses. Maker fringes due to phase‐matching requirements were clearly observed, and phase‐matched nondegenerate mixing was achieved by utilizing the waveguide geometrical birefringence. Conversion efficiency up to 5×10−3 for a coherent interaction length of 3 mm was obtained. The observed third‐order nonlinear susceptibility χ(3)(ω3=ω1+ω1−ω2) does not display any strong resonances and exhibits a relaxation time shorter than 10 ps. From these measurements it is inferred that ‖χ(3)1111‖≥8×10−11 esu, and ‖χ(3)1111/χ(3)2112‖=2.4±0.3 for ω1 and ω2≊1480 meV/ℏ.
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42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
42.79.Gn Optical waveguides and couplers
78.47.-p Spectroscopy of solid state dynamics

Generation of femtosecond electromagnetic pulses from semiconductor surfaces

X.‐C. Zhang, B. B. Hu, J. T. Darrow, and D. H. Auston

Appl. Phys. Lett. 56, 1011 (1990); http://dx.doi.org/10.1063/1.102601 (3 pages) | Cited 123 times

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We have generated electromagnetic beams from a variety of semiconductors. When a bare semiconductor wafer was illuminated by femtosecond optical pulses, electromagnetic waves radiate from the surface and form collinear diffraction‐limited electromagnetic beams in the inward and outward directions. The amplitude and phase of the radiated field depend on carrier mobility, the strength and polarity of the static internal field at the semiconductor surface.
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42.65.Re Ultrafast processes; optical pulse generation and pulse compression
73.20.-r Electron states at surfaces and interfaces

Double‐heterostructure GaAs/AlGaAs lasers on Si substrates with reduced threshold current and built‐in index guiding by selective‐area molecular beam epitaxy

Henry P. Lee, Xiaoming Liu, and Shyh Wang

Appl. Phys. Lett. 56, 1014 (1990); http://dx.doi.org/10.1063/1.102602 (3 pages) | Cited 9 times

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We report successful fabrication of GaAs/Al0.26Ga0.74As double‐heterostructure laser diodes grown on patterned Si substrates by molecular beam epitaxy. The patterned substrates consist of exposed Si stripes with widths ranging from 9 to 70 μm and surrounded by 900 Å of SiN films on both sides. Oxide‐defined contact stripe lasers with stripe widths ranging from 3 to 50 μm (corresponding to each of the SiN‐defined stripe windows) were fabricated. Reduction of laser threshold current densities compared to similar lasers grown on nonpatterned Si substrates is observed, and is attributed to current confinement effect by the high‐resistivity polycrystalline GaAs/AlGaAs films surrounding the active devices. From the measurements on the longitudinal mode spectrum and far‐field patterns, lateral index guiding is also observed for the 10‐μm‐wide selective‐area grown laser.
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42.55.Px Semiconductor lasers; laser diodes
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Optical bistability in hydrogenated amorphous silicon

J. Tann, M. Gal, K. Meaney, and P. C. Taylor

Appl. Phys. Lett. 56, 1017 (1990); http://dx.doi.org/10.1063/1.103183 (2 pages) | Cited 4 times

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Room‐temperature optical bistability has been demonstrated in hydrogenated amorphous silicon at wavelengths greater than about 700 nm. Switching powers as low as 0.8 mW (switching intensities 1.7 kW/cm2) are observed. The measured switching times are found to be compound, with time constants from 50 μs to 1 ms.
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42.65.Pc Optical bistability, multistability, and switching, including local field effects
78.66.-w Optical properties of specific thin films
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks

Acoustic microscopy at 15.3 GHz in pressurized superfluid helium

M. S. Muha, A. A. Moulthrop, G. C. Kozlowski, and B. Hadimioglu

Appl. Phys. Lett. 56, 1019 (1990); http://dx.doi.org/10.1063/1.102603 (3 pages) | Cited 4 times

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An acoustic microscope operating at 15.3 GHz and using superfluid 4He as the coupling medium has been developed. The helium is colder than 0.9 K to achieve low acoustic attenuation, and is pressurized to greater than 20 bar to eliminate three‐phonon processes which saturate the received signal as the input power is increased. A resolution of 150 Å has been achieved.
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43.35.Sx Acoustooptical effects, optoacoustics, acoustical visualization, acoustical microscopy, and acoustical holography
67.25.dt Sound and excitations

Electron heating in low‐pressure rf glow discharges

M. Surendra, D. B. Graves, and I. J. Morey

Appl. Phys. Lett. 56, 1022 (1990); http://dx.doi.org/10.1063/1.102604 (3 pages) | Cited 77 times

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Particle‐in‐cell simulations of radio frequency glow discharges between parallel‐plate electrodes were performed to test the role of secondary emission at applied frequencies above the ion plasma frequency. With the secondary electron emission coefficient set to zero, the high‐energy tail of the electron energy distribution function in the center of the glow is modulated at the applied frequency, and these energetic electrons show substantial anisotropy. In addition, a pulse of ionization propagates across the glow, correpsonding to the directed velocity of the high‐energy electrons in the center of the glow. These high‐energy electrons originate at the plasma‐sheath boundary and appear to be the result of sheath heating.
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52.65.-y Plasma simulation
52.40.Hf Plasma-material interactions; boundary layer effects
52.80.Hc Glow; corona

Nucleation of amorphous germanium from supercooled melts

S. R. Stiffler, Michael O. Thompson, and P. S. Peercy

Appl. Phys. Lett. 56, 1025 (1990); http://dx.doi.org/10.1063/1.103326 (3 pages) | Cited 18 times

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Thin germanium films on SiO2 completely melted by pulsed laser irradiation cool rapidly by thermal conduction to the substrate until they solidify. In situ measurements indicate that the liquid is supercooled by 420–530 K with respect to the crystalline phase prior to solidification. Cross‐sectional transmission electron microscopy reveals nucleation events at the Ge/SiO2 interface. The microstructure of these events is comprised of a very fine grained (5–15 nm) polycrystalline core with much larger grains extending laterally and toward the free surface. It is believed that nucleation of the amorphous phase, which was subsequently converted to the fine‐grained material, initiated solidification.
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64.60.Q- Nucleation
64.70.D- Solid-liquid transitions

Pt/Ti ohmic contacts to ultrahigh carbon‐doped p‐GaAs formed by rapid thermal processing

A. Katz, C. R. Abernathy, and S. J. Pearton

Appl. Phys. Lett. 56, 1028 (1990); http://dx.doi.org/10.1063/1.102605 (3 pages) | Cited 26 times

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Increasing the concentration of the carbon dopants in p‐GaAs layers grown on semi‐insulating substrates to levels of 1×1020 to 5×1020 cm−3 enables the formation of an ohmic contact with low resistance using the refractory Pt/Ti metallization. These contacts showed ohmic behavior prior to any heat treatment with specific contact resistance as low as 7×10−6 Ω cm2 (0.08 Ω mm) for the lower doping level and 8×10−7 Ω cm2 (0.04 Ω mm) for the higher level. Small improvements in the specific resistance of the former contact were achieved by rapid thermal processing at a temperature of 450 °C for 30 s, which yielded a value of 4.9×10−6 Ω cm2. The electrical nature of the contact to the heavily doped GaAs was not affected by heat treatments at temperatures up to 450 °C. Rapid thermal processing of these contacts at higher temperatures, however, caused an increase in the contact resistance which was correlated to the expanded Ti/GaAs and Pt/GaAs interfacial reactions. Current‐voltage characteristics were found to be temperature independent. This suggested that the field emission quantum‐mechanical tunneling was the dominant carrier transport mechanism in these contacts.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
72.80.Ey III-V and II-VI semiconductors
73.40.Ns Metal-nonmetal contacts
81.40.Gh Other heat and thermomechanical treatments

Improvement on the current‐voltage characteristics of polycrystalline silicon contacted n+‐p junctions with high‐field stressing

S. L. Wu, C. L. Lee, and T. F. Lei

Appl. Phys. Lett. 56, 1031 (1990); http://dx.doi.org/10.1063/1.102606 (3 pages) | Cited 1 time

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Improvement on the current‐voltage characteristics of polycrystalline silicon contacted n+‐p junctions after they were applied a high‐field scanned stressing is reported. For the stressed diodes, the leakage current decreased as much as two orders, the breakdown voltage shifted from −45 to −60 V, and the forward ideality factor also decreased. Scanning electron microscopy photographs on the cross‐sectional view of the junctions revealed that local melting might have occurred during stressing to cause the improvement.
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73.20.At Surface states, band structure, electron density of states
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.50.Fq High-field and nonlinear effects
73.61.Ey III-V semiconductors

Switching characteristics of hydrogenated amorphous silicon/crystalline silicon heterojunction devices

Yu‐Wen Chen, Yean‐Kuen Fang, Hong‐Da Lee, and Chun‐Yen Chang

Appl. Phys. Lett. 56, 1034 (1990); http://dx.doi.org/10.1063/1.102607 (3 pages) | Cited 9 times

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A new structure of a three‐terminal hydrogenated amorphous silicon/crystalline silicon (a‐Si:H/c‐Si) heterojunction switching device is successfully developed. The device can be controlled by a gate bias. The switching voltage, holding voltage, and switching current all increase with an increase of undoped a‐Si:H thickness. The electrical characteristics and switching phenomena of this device are discussed.
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85.40.-e Microelectronics: LSI, VLSI, ULSI; integrated circuit fabrication technology
85.60.-q Optoelectronic devices
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks

Trapped positive charge in plasma‐enhanced chemical vapor deposited silicon dioxide films

D. A. Buchanan, J. H. Stathis, and P. R. Wagner

Appl. Phys. Lett. 56, 1037 (1990); http://dx.doi.org/10.1063/1.103327 (3 pages) | Cited 12 times

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We report an investigation of trapped positive charge in as‐fabricated plasma‐enhanced chemical vapor deposited SiO2 films using electrical and spin resonance techniques. We show that the positive charge results from donor‐like ‘‘slow’’ interface states (‘‘anomalous positive charge’’) rather than trapped holes, and that most (∼95%) of the positive charge is not related to E′ centers. The positive charge is similar to that seen in electron‐injected thermally grown SiO2, and unlike radiation‐induced trapped holes.
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73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
71.23.An Theories and models; localized states
73.61.Ng Insulators
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Lattice contraction due to carbon doping of GaAs grown by metalorganic molecular beam epitaxy

T. J. de Lyon, J. M. Woodall, M. S. Goorsky, and P. D. Kirchner

Appl. Phys. Lett. 56, 1040 (1990); http://dx.doi.org/10.1063/1.102608 (3 pages) | Cited 74 times

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Epitaxial layers of GaAs have been grown by metalorganic molecular beam epitaxy (MOMBE) with atomic carbon concentrations ranging from 4×1017 to 3.5×1020 cm−3. The dependences of GaAs lattice parameter and hole concentration on atomic carbon concentration have been determined from x‐ray diffraction, Hall effect, and secondary‐ion mass spectrometry measurements. For atomic carbon concentrations in excess of 1×1019 cm−3, the hole concentrations are less than the corresponding atomic carbon concentrations. Lattice parameter shifts as large as 0.2% are observed for carbon concentrations in excess of 1×1020 cm−3, which results in misfit dislocation generation in some cases due to the lattice mismatch between the C‐doped epilayer and undoped substrate. Over the entire range of carbon concentrations investigated, Vegard’s law accurately predicts the observed lattice contraction.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
68.55.-a Thin film structure and morphology
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
61.05.cf X-ray scattering (including small-angle scattering)
61.05.cj X-ray absorption spectroscopy: EXAFS, NEXAFS, XANES, etc.

Electrical and optical characterization of back‐to‐back Schottky (Al,Ga)As/NiAl/(Al,Ga)As molecular beam epitaxially grown double‐heterostructure diodes

T. L. Cheeks, T. Sands, R. E. Nahory, J. Harbison, N. Tabatabaie, H. L. Gilchrist, B. J. Wilkens, and V. G. Keramidas

Appl. Phys. Lett. 56, 1043 (1990); http://dx.doi.org/10.1063/1.102609 (3 pages) | Cited 2 times

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Current‐voltage, capacitance‐voltage, and internal photoemission measurements of back‐to‐back Schottky diodes of buried metal (Al,Ga)As/NiAl/(Al,Ga)As double heterostructures grown by molecular beam epitaxy are reported. By using a selective etch process to access the buried layers and fabricate three‐terminal devices, independent measurements of the barrier height on both sides of the buried metal double heterostructure were performed. Schottky diode behavior was observed for both upper and lower diodes and the barrier height was measured to be 1.1 eV for both diodes using internal photoemission. Electrical measurements showed a lower effective barrier height for the upper metal‐semiconductor interface as compared to the lower interface in agreement with the different defect densities in these heterostructures.
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73.30.+y Surface double layers, Schottky barriers, and work functions
73.40.Lq Other semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
79.60.-i Photoemission and photoelectron spectra

Observation of large oscillator strengths for both 1→2 and 1→3 intersubband transitions of step quantum wells

Y. J. Mii, K. L. Wang, R. P. G. Karunasiri, and P. F. Yuh

Appl. Phys. Lett. 56, 1046 (1990); http://dx.doi.org/10.1063/1.102610 (3 pages) | Cited 33 times

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Both 1→2 and 1→3 intersubband transitions have been observed in a step quantum well structure consisting of 60 Å GaAs wells, 90 Å Al0.18Ga0.82As steps, and 280 Å Al0.44 Ga0.56As barriers. The transition energy and oscillator strength are 112 meV and 0.23 for the 1→2 transition and 150 meV and 0.15 for the 1→3 transition, respectively. The asymmetric property of a step quantum well allows the normally forbidden 1→3 transition to occur. The relaxation of the selection rule suggests a possibility of using optical pumping for infrared laser applications.
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73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
78.30.Fs III-V and II-VI semiconductors
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors

Mapping of local temperatures on mirrors of GaAs/AlGaAs laser diodes

Hans Brugger and Peter W. Epperlein

Appl. Phys. Lett. 56, 1049 (1990); http://dx.doi.org/10.1063/1.102611 (3 pages) | Cited 64 times

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Spatially resolved Raman scattering measurements (<1 μm) have been performed to determine the surface temperature distribution on coated and uncoated facets of ridge‐waveguided GaAs/AlGaAs single quantum well graded‐index separate‐confinement heterostructure lasers. A strong nonlinear temperature versus output‐power dependence is observed for cleaved, uncoated mirrors (ΔT>100 K for P>1 MW/cm2). Raman line scans show hot spot regions at the facets. Degradation strength correlates with facet heating. Disorder‐activated Raman phonon modes indicate strong crystal damage. Laser mirrors with λ/2‐Al2O3 coatings withstand up to 4–5 times the power density without significant heating and degradation. Local electroluminescence measurements along the cavity confirm increasing temperatures when approaching the facets and show that the resonator bulk material remains cold (ΔT<5 K).
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42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
42.55.Px Semiconductor lasers; laser diodes
78.30.Hv Other nonmetallic inorganics

Superhot electron model for ionizing radiation dose rate response of GaAs junction field‐effect transistors

K. Lehovec, J. K. Notthoff, and R. Zuleeg

Appl. Phys. Lett. 56, 1052 (1990); http://dx.doi.org/10.1063/1.102612 (3 pages)

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The ionizing radiation dose rate response of GaAs junction field‐effect transistors (JFETs) cannot be explained by the usual photocurrent model. A model is proposed in which superhot electrons from a region of many tens of microns are collected ballistically over the repulsive built‐in P+ gate barrier of irradiated n‐JFETs providing a gate current of polarity opposite to that of the ordinary junction photocurrent. Steady state is established by inflow of thermal electrons from the source which increases the bulk electron concentration and causes a drift velocity saturated drain current through the substrate at positive drain voltages. Since collection range of holes is much shorter than of electrons, p‐JFETs do not exhibit this effect.
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72.80.Ey III-V and II-VI semiconductors
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
61.80.Fe Electron and positron radiation effects
85.30.De Semiconductor-device characterization, design, and modeling

Resonant Raman studies of structural ordering in Hg1−xCdxTe: Dependence on growth conditions

A. Compaan, R. C. Bowman, and D. E. Cooper

Appl. Phys. Lett. 56, 1055 (1990); http://dx.doi.org/10.1063/1.102613 (3 pages) | Cited 12 times

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Resonant Raman scattering with photon energies between 2.35 and 2.7 eV has been used to study both the alloy composition and local structural order in Hg1−xCdxTe for x values near 0.25 and for samples prepared by bulk growth, liquid phase epitaxy, molecular beam epitaxy, and metalorganic chemical vapor deposition. The resonance behavior of the HgTe‐like transverse optical and longitudinal optical (LO) modes, the CdTe‐like LO mode, and that of an additional mode probably due to preferential clustering of three Hg and one Cd about the Te sites, all indicate strong enhancement at the E1 edge. However, surfaces annealed with a Nd:yttrium‐aluminum‐garnet‐pumped dye laser show strong suppression of the cluster mode (but not the LO mode) in all samples, which suggests that extremely rapid epitaxial regrowth may inhibit the 3:1 cluster formation.
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78.30.Fs III-V and II-VI semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.40.Tv Optical and dielectric properties related to treatment conditions
81.15.Lm Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids)

p‐channel negative resistance field‐effect transistor

M. E. Favaro, L. M. Miller, R. P. Bryan, J. J. Alwan, and J. J. Coleman

Appl. Phys. Lett. 56, 1058 (1990); http://dx.doi.org/10.1063/1.102564 (3 pages) | Cited 3 times

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We experimentally demonstrate the first p‐channel negative resistance field‐effect transistor. Low‐temperature current‐voltage characteristics exhibit negative differential resistance in the drain circuit which is controlled by the substrate voltage. The negative differential resistance is attributed to the real‐space transfer of holes.
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85.30.Tv Field effect devices
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
72.20.Ht High-field and nonlinear effects
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
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