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5 Oct 1987

Volume 51, Issue 14, pp. 1051-1123


Nearly degenerate four‐wave mixing in a traveling‐wave semiconductor laser amplifier

Kyo Inoue, Takaaki Mukai, and Tadashi Saitoh

Appl. Phys. Lett. 51, 1051 (1987); http://dx.doi.org/10.1063/1.99004 (3 pages) | Cited 26 times

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Nearly degenerate four‐wave mixing (NDFWM) in a traveling‐wave semiconductor laser amplifier is demonstrated by simultaneously injecting two lights of slightly different frequencies in the same direction. A new frequency light at an expected frequency for NDFWM is observed with the same order of output as that of the injected light. The output power ratio of the three beams is strongly dependent on the sign of the frequency detuning. Theoretical analysis, in which the carrier rate equation is coupled with nonlinear Maxwell’s equations, explains the experimental results well. The observed behaviors are attributed to a unique third‐order nonlinearity stemming from saturation‐induced refractive index change in the semiconductor gain medium.
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42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.55.Px Semiconductor lasers; laser diodes
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation

Planar‐embedded InGaAsP/InP heterostructure laser with a semi‐insulating InP current‐blocking layer grown by metalorganic chemical vapor deposition

T. Sanada, K. Nakai, K. Wakao, M. Kuno, and S. Yamakoshi

Appl. Phys. Lett. 51, 1054 (1987); http://dx.doi.org/10.1063/1.98789 (3 pages) | Cited 24 times

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We used metalorganic chemical vapor deposition to fabricate a planar‐embedded InGaAsP/InP heterostructure laser with a semi‐insulating InP current‐blocking layer. The laser exhibits cw operation with a low, 20 mA threshold current and a high external differential quantum efficiency of 40% at room temperature. Measurements have also shown a small‐signal frequency response of 10 GHz due to an extremely small parasitic capacitance of 3.5 pF.
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42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.55.Px Semiconductor lasers; laser diodes
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties

Staggered hollow‐bore CO2 waveguide laser array

R. A. Hart, L. A. Newman, A. J. Cantor, and J. T. Kennedy

Appl. Phys. Lett. 51, 1057 (1987); http://dx.doi.org/10.1063/1.98790 (3 pages) | Cited 6 times

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A modified hollow‐bore ridge waveguide, utilizing a staggered ridge geometry, has been used successfully to obtain single‐frequency operation from an array of CO2 waveguide lasers. The gain volume of the array is equivalent to six waveguide lasers of 37 cm length and 2.25×2.25 mm2 cross section. The output power from the sealed‐off device reached 68 W cw. Stable single‐frequency operation in the antisymmetric supermode was observed.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
42.60.Fc Modulation, tuning, and mode locking

Wavelength selective interlayer directionally grating‐coupled InP/InGaAsP waveguide photodetection

T. L. Koch, P. J. Corvini, W. T. Tsang, U. Koren, and B. I. Miller

Appl. Phys. Lett. 51, 1060 (1987); http://dx.doi.org/10.1063/1.98791 (3 pages) | Cited 14 times

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We present the first demonstration of interlayer, or vertical, directional grating coupling using a permanently incorporated corrugated layer grating. Based on an InP/InGaAsP antiresonant reflecting optical waveguide (ARROW) geometry grown by chemical beam epitaxy and metalorganic chemical vapor deposition, we have achieved a large mode contradirectional grating‐coupled waveguide photodetector with a spectral response peak 9 Å wide. The ‘‘optical bus’’ capabilities of the vertically coupled ARROW structure make this device suitable for optical integration.
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42.82.-m Integrated optics
42.79.Dj Gratings
42.79.Gn Optical waveguides and couplers
42.79.Sz Optical communication systems, multiplexers, and demultiplexers

Narrowband, single line, 1 μs XeF laser

W. D. Kimura, Dean R. Guyer, J. F. Seamans, and D. H. Ford

Appl. Phys. Lett. 51, 1063 (1987); http://dx.doi.org/10.1063/1.98792 (3 pages) | Cited 1 time

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A narrowband (5 GHz) electron beam pumped XeF oscillator/amplifier, lasing at 353.2 nm over a 1‐μs pulse duration, has been demonstrated. Line selection, bandwidth narrowing, and near‐diffraction‐limited output are achieved by using an echelle grating and an intracavity solid étalon in a stable oscillator configuration. The amplifier features an off‐axis design and yields output energies ≳0.8 J. The oscillator and amplifier are located in the same gas chamber and are transversely pumped by the same electron beam. A Fabry–Perot interferometer together with a streak camera is used to verify narrowband operation over the entire pulse duration.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation

Estimation of the thickness of thin metal sheet using laser generated ultrasound

R. J. Dewhurst, C. Edwards, A. D. W. McKie, and S. B. Palmer

Appl. Phys. Lett. 51, 1066 (1987); http://dx.doi.org/10.1063/1.98793 (3 pages) | Cited 65 times

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A noncontacting technique has been developed to measure the thickness of thin metal sheet by using a pulsed laser to generate both symmetric and antisymmetric Lamb waves. These have been detected with a laser interferometer. Analysis of the waveforms allows an estimation of the sheet thickness and accuracies to within 2% are attainable on sheets as thin as 27 μm.
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81.70.-q Methods of materials testing and analysis
43.35.Zc Use of ultrasonics in nondestructive testing, industrial processes, and industrial products
43.35.Cg Ultrasonic velocity, dispersion, scattering, diffraction, and attenuation in solids; elastic constants
43.35.Sx Acoustooptical effects, optoacoustics, acoustical visualization, acoustical microscopy, and acoustical holography

New method to relax thermal stress in GaAs grown on Si substrates

Shiro Sakai

Appl. Phys. Lett. 51, 1069 (1987); http://dx.doi.org/10.1063/1.98794 (3 pages) | Cited 6 times

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A new method to grow stress‐free GaAs on bent Si substrates is proposed and demonstrated by metalorganic chemical vapor deposition. The stress produced by the thermal expansion coefficient difference of Si and GaAs is compensated by the external mechanical strain applied in the substrate at high temperature. The photoluminescence peak energy of GaAs on Si becomes almost the same as that of the stress‐free GaAs on GaAs grown by liquid phase epitaxy by applying this method.
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68.60.Bs Mechanical and acoustical properties
78.55.Cr III-V semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
65.40.De Thermal expansion; thermomechanical effects

Analysis of initial stage of Pd‐Si (111) and Au‐Si (111) interface reactions by means of high‐resolution proton energy‐loss spectroscopy

Jun‐ichi Kanasaki, Noriaki Itoh, and Noriaki Matsunami

Appl. Phys. Lett. 51, 1072 (1987); http://dx.doi.org/10.1063/1.98743 (3 pages) | Cited 1 time

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High‐resolution spectroscopy of protons incident under nonchanneling condition and scattered by 12° on Pd‐ and Au‐deposited Si(111) surfaces has been employed for direct layer‐by‐layer analysis of the depth distribution of Au and Pd. For nearly monolayer deposition at room temperature, most of the Au atoms are found to remain on the silicon surface, while the Pd atoms are found to be distributed over the two layers, with the palladium composition not exceeding that of Pd2Si. We also found that the most probable energy loss of protons scattered from the Au‐deposited surface is sensitive to the depth of the Au atoms on the surface.
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68.35.Dv Composition, segregation; defects and impurities
68.35.B- Structure of clean surfaces (and surface reconstruction)
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

High‐efficiency Al0.3Ga0.7As solar cells grown by molecular beam epitaxy

Chikara Amano, Hideo Sugiura, Koshi Ando, Masafumi Yamaguchi, and Anne Saletes

Appl. Phys. Lett. 51, 1075 (1987); http://dx.doi.org/10.1063/1.98744 (3 pages) | Cited 2 times

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This letter reports the growth of high‐efficiency Al0.3Ga0.7As solar cells by molecular beam epitaxy. As the growth temperature increases from 650 to 750 °C, the concentration of midgap electron traps in the active layers decreases from 4×1015 to less than 3×1013 cm−3 and the hole diffusion length in the layers improves from 2.0 to 2.6 μm. For cells grown at 750 °C, an efficiency of 14.6% (AM1.5, 100 mW/cm2 for an active area) is obtained.
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84.60.Jt Photoelectric conversion
72.40.+w Photoconduction and photovoltaic effects
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
71.55.Eq III-V semiconductors

Deep level transient spectroscopy studies of epitaxial silicon layers on silicon‐on‐insulator substrates formed by oxygen implantation

P. K. McLarty, J. W. Cole, K. F. Galloway, D. E. Ioannou, and S. E. Bernacki

Appl. Phys. Lett. 51, 1078 (1987); http://dx.doi.org/10.1063/1.98745 (2 pages) | Cited 10 times

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Deep level transient spectroscopy was applied to study silicon epitaxial layers of varying thickness grown on silicon‐on‐insulator substrates formed by oxygen implantation. For 3‐μm‐thick layers no traps were detected. For 1.0‐, 2.0‐, and 2.5‐μm‐thick layers electron traps were found with levels 0.34, 0.32, and 0.37 eV below the conduction‐band edge, and corresponding capture cross sections of ∼2.0×10−7, 6.0×10−18, and 5.0×10−7 cm2. These levels were found to be uniformly distributed across the wafer. It was also observed that the trap concentration is a decreasing function of epilayer thickness.
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71.55.Ht Other nonmetals
73.20.Hb Impurity and defect levels; energy states of adsorbed species
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping

Role of experimental resolution in measurements of critical layer thickness for strained‐layer epitaxy

I. J. Fritz

Appl. Phys. Lett. 51, 1080 (1987); http://dx.doi.org/10.1063/1.98746 (3 pages) | Cited 105 times

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Experimental measurements of critical layer thicknesses (CLT’s) in strained‐layer epitaxy are considered. Finite experimental resolution can have a major effect on measured CLT’s and can easily lead to spurious results. The theoretical approach to critical layer thicknesses of J. W. Matthews [J. Vac. Sci. Technol. 12, 126 (1975)] has been modified in a straightforward way to predict the apparent critical thickness for an experiment with finite resolution in lattice parameter. The theory has also been modified to account for the general empirical result that fewer misfit dislocations are generated than predicted by equilibrium calculation. The resulting expression is fit to recent x‐ray diffraction data on InGaAs/GaAs and SiGe/Si. The results suggest that CLT’s in these systems may not be significantly larger than predicted by equilibrium theory, in agreement with high‐resolution measurements.
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68.55.-a Thin film structure and morphology
68.35.Dv Composition, segregation; defects and impurities
81.15.Np Solid phase epitaxy; growth from solid phases

Reactive ion etch process with highly controllable GaAs‐to‐AlGaAs selectivity using SF6 and SiCl4

S. Salimian, C. B. Cooper, R. Norton, and J. Bacon

Appl. Phys. Lett. 51, 1083 (1987); http://dx.doi.org/10.1063/1.98747 (3 pages) | Cited 26 times

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The use of a reactive ion etch process with high selectivity for etching GaAs layers and stopping on underlying AlGaAs layers is reported. A key feature is the high degree of control that can be maintained over the GaAs‐to‐AlGaAs selectivity by changing the SF6/SiCl4 ratio while keeping other etch parameters such as pressure, dc bias, or power constant. Values of the GaAs‐to‐AlGaAs selectivity can be varied from 1 to 500. Diluent gases such as helium can be added to reduce the etch rate, which is important to avoid damage to sensitive device structures and to the overhang profile of resist materials used for liftoff metallization. The application of this etch process for high electron mobility transistor fabrication is discussed.
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81.65.-b Surface treatments
85.40.Bh Computer-aided design of microcircuits; layout and modeling
85.30.De Semiconductor-device characterization, design, and modeling
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces

Mode‐locked infrared sensor

D. D. Coon and A. G. U. Perera

Appl. Phys. Lett. 51, 1086 (1987); http://dx.doi.org/10.1063/1.98748 (3 pages) | Cited 4 times

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Injection mode infrared detector concepts are expanded to incorporate the nonlinear dynamics concept of mode locking. The first successful demonstration of this approach is reported. The detectors employ extrinsic silicon and have large output signals which require no electronic amplification. Mode locking greatly reduces fluctuations in detector output without a corresponding reduction in detector responsivity. The results could lead to the development of a new class of sensors which exploit recent work on the distinction between deterministic fluctuations in nonlinear systems and intrinsic noise.
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85.60.Gz Photodetectors (including infrared and CCD detectors)
73.40.Lq Other semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
78.30.-j Infrared and Raman spectra
78.40.Fy Semiconductors
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing

Resonant level lifetime in GaAs/AlGaAs double‐barrier structures

Thomas B. Bahder, Clyde A. Morrison, and John D. Bruno

Appl. Phys. Lett. 51, 1089 (1987); http://dx.doi.org/10.1063/1.98749 (2 pages) | Cited 44 times

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The lifetime of the lowest quasibound state localized between the barriers of a GaAs/AlGaAs double‐barrier structure is calculated as a function of barrier and well dimensions. The results are consistent with high‐frequency experiments.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
73.61.Ey III-V semiconductors

Enhancement in excitonic absorption due to overlap in heavy‐hole and light‐hole excitons in GaAs/InAlGaAs quantum well structures

G. P. Kothiyal, S. Hong, N. Debbar, P. K. Bhattacharya, and J. Singh

Appl. Phys. Lett. 51, 1091 (1987); http://dx.doi.org/10.1063/1.98750 (3 pages) | Cited 17 times

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In this letter we present experimental and theoretical results for excitonic transitions in coherently strained GaAs/InGaAlAs multiquantum well structures grown on a GaAs substrate. Absorption spectra of the structure with the substrate removed show an extremely sharp exciton peak with an absorption constant corresponding to nearly twice the value of that in the lattice‐matched GaAs/AlGaAs system. Theoretical calculations suggest that the biaxial tensile strain in the well region, occurring after the substrate is removed, causes the heavy‐hole and light‐hole exciton states to coincide for a specific composition of the quaternary alloy. A comparison between the experiments and theory is made and the potential for devices based on this phenomenon is discussed.
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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
73.61.Ey III-V semiconductors
78.30.-j Infrared and Raman spectra
78.40.Fy Semiconductors

Resolution of amorphous silicon thin‐film transistor instability mechanisms using ambipolar transistors

C. van Berkel and M. J. Powell

Appl. Phys. Lett. 51, 1094 (1987); http://dx.doi.org/10.1063/1.98751 (3 pages) | Cited 75 times

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Bias stress measurements on amorphous silicon‐silicon nitride ambipolar thin‐film transistors give clear evidence for the co‐existence of two distinct instability mechanisms: the metastable creation of states in the a‐Si:H layer and charge trapping in the a‐SiN:H layer. The creation of metastable states in the a‐Si:H is found to dominate at low positive bias, while charge trapping in the nitride dominates at larger positive bias and negative bias.
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85.30.Pq Bipolar transistors
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems

High‐speed operation of InP metal‐insulator‐semiconductor field‐effect transistors grown by chloride vapor phase epitaxy

A. Antreasyan, P. A. Garbinski, V. D. Mattera, H. Temkin, and J. H. Abeles

Appl. Phys. Lett. 51, 1097 (1987); http://dx.doi.org/10.1063/1.98752 (3 pages) | Cited 6 times

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We report the millimeter‐wave performance of enhancement mode InP metal‐insulator‐semiconductor field‐effect transistors grown by chloride vapor phase epitaxy. For a gate length of 1 μm we have measured a current gain cutoff frequency of 29 GHz and an electron velocity of 2.5×107 cm/s, close to a theoretical current gain cutoff frequency of 40 GHz. This represents the fastest InP‐based field‐effect transistor ever demonstrated, and surpasses state‐of‐the‐art AlGaAs/GaAs modulation‐doped field‐effect transistors having similar gate length.
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85.30.Tv Field effect devices
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
73.61.Ng Insulators

Electrical transport and in situ x‐ray studies of the formation of TiSi2 thin films on Si

J. C. Hensel, J. M. Vandenberg, F. C. Unterwald, and A. Maury

Appl. Phys. Lett. 51, 1100 (1987); http://dx.doi.org/10.1063/1.98753 (3 pages) | Cited 19 times

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The formation of TiSi2 thin films on Si has been investigated by in situ x‐ray diffraction and electrical transport. The x‐ray results show unequivocally that the staging proceeds through two orthorhombic polytypes of TiSi2 according to the sequence: sputter‐deposited metallic Ti or TiSix alloy films on Si(001)→TiSi2 (C49 structure)→TiSi2 (C54 structure), with no evidence of lower silicides. Electrical transport shows metallic behavior for all phases and distinctive features in the annealing curves which correlate with the structural transformations. Most important, the resistivity, characteristically very high for the C49 phase, undergoes a precipitous drop at the C49→C54 transition. In the C54 phase when fully annealed the resistivity is 12.4 μΩ cm at room temperature and 0.66 μΩ cm at 4.2 K.
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81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
73.61.At Metal and metallic alloys
68.55.Nq Composition and phase identification
73.50.-h Electronic transport phenomena in thin films

Identification of an interstitial carbon‐interstitial oxygen complex in silicon

J. M. Trombetta and G. D. Watkins

Appl. Phys. Lett. 51, 1103 (1987); http://dx.doi.org/10.1063/1.98754 (3 pages) | Cited 73 times

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An electron paramagnetic resonance spectrum, observed in electron irradiated silicon and labeled Si‐G15, is shown to originate from the same carbon‐oxygen complex as does the well studied C‐line photoluminescence spectrum with zero‐phonon line at 0.79 eV. Both the g tensor and the 13C hyperfine tensor for this center are remarkably similar to those for the isolated interstitial carbon atom. Stress‐induced alignment experiments reveal the role of oxygen and indicate a unique structure for an interstitial carbon‐interstitial oxygen pair.
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61.72.jd Vacancies
61.72.jj Interstitials
61.72.Bb Theories and models of crystal defects
76.30.Lh Other ions and impurities
71.55.Ht Other nonmetals

NiSi2 precipitation in nickel‐implanted silicon films

R. C. Cammarata, C. V. Thompson, and K. N. Tu

Appl. Phys. Lett. 51, 1106 (1987); http://dx.doi.org/10.1063/1.99003 (3 pages) | Cited 21 times

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We report on the formation of nickel silicide in nickel‐implanted amorphous silicon thin films. We have found that during annealing, precipitates of NiSi2 form in the interior of the film. This is in contrast with results for interfacial reactions between nickel films and silicon, where the first phases to appear are Ni2Si and NiSi on amorphous silicon, and Ni2Si on crystalline silicon. We suggest that these results reflect differences in surface energies and their effects on silicide nucleation.
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81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
81.30.Mh Solid-phase precipitation
81.40.Cd Solid solution hardening, precipitation hardening, and dispersion hardening; aging
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization

Chemical beam epitaxial growth of high‐purity GaAs using triethylgallium and arsine

T. H. Chiu, W. T. Tsang, E. F. Schubert, and E. Agyekum

Appl. Phys. Lett. 51, 1109 (1987); http://dx.doi.org/10.1063/1.98755 (3 pages) | Cited 12 times

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The growth of high‐purity GaAs by chemical beam epitaxy using triethylgallium and arsine is reported. Purity of the epilayer is affected by the cracking efficiency of arsine, V/III ratio, and the substrate temperature. Samples generally show p‐type conductivity with carbon as the residual impurity. The growth conditions to achieve net carrier concentration below 1014 cm−3 are identified. The low‐temperature photoluminescence spectrum shows well‐resolved excitonic structures, an indication of excellent optical quality.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
73.61.Ey III-V semiconductors

Pulsed laser etching of high Tc superconducting films

Arun Inam, X. D. Wu, T. Venkatesan, S. B. Ogale, C. C. Chang, and D. Dijkkamp

Appl. Phys. Lett. 51, 1112 (1987); http://dx.doi.org/10.1063/1.98756 (3 pages) | Cited 84 times

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Etching of Y‐Ba‐Cu‐O superconducting thin films has been accomplished using a pulsed excimer laser (248 nm, 30 ns). Etch depth as a function of the number of laser pulses was linear over a wide range of incident laser energy densities. An etch threshold energy density of 0.11 J/cm2 was observed and etch rate per pulse scaled linearly with the logarithm of the incident energy density. The dependence is adequately explained by a linear absorption model with an inverse absorption length of 2.3×105 cm−1.
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81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
81.65.-b Surface treatments
79.20.Ds Laser-beam impact phenomena

High‐temperature resistivity of the Ba2YCu3Ox superconductor

G. Sageev Grader, P. K. Gallagher, and E. M. Gyorgy

Appl. Phys. Lett. 51, 1115 (1987); http://dx.doi.org/10.1063/1.98757 (3 pages) | Cited 31 times

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The resistivity of Ba2YCu3Ox was measured in the 450–850 °C range at various oxygen partial pressures. The tetragonal to orthorhombic phase transition is observed as a change in the slope of the resistivity curve. The lack of a discontinuity in the curve is consistent with the phase transition being higher than first order. It was found that decreasing the oxygen content x below 6.2 changed the resistivity of the tetragonal phase from metallic character to semiconducting character. In the metallic region of the tetragonal phase the superconducting transition temperature is depressed below 60 K, while in the semiconducting region, no superconducting onset was observed down to 6 K. In the orthorhombic phase, the resistivity of the material is shown to be governed by the number of oxygens per unit cell, suggesting that the resistivity can serve as a quality control parameter in the production of superconducting devices.
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72.80.Jc Other crystalline inorganic semiconductors

Spectroscopic evidence for passivation of the La1.85Sr0.15CuO4 surface with gold

H. M. Meyer, T. J. Wagener, D. M. Hill, Y. Gao, S. G. Anderson, S. D. Krahn, J. H. Weaver, B. Flandermeyer, and D. W. Capone

Appl. Phys. Lett. 51, 1118 (1987); http://dx.doi.org/10.1063/1.98758 (3 pages) | Cited 18 times

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High‐resolution x‐ray photoemission and inverse photoemission have been used to study the microscopic formation of Au overlayers on the high Tc superconductor La1.85Sr0.15CuO4. Our results indicate that Au does not induce disruption or surface reaction, unlike the reactive transition metals. The electronic states of the superconductor are attenuated as the Au overlayer covers the surface. We conclude that Au is a promising material for metallization and for passivation.
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73.20.At Surface states, band structure, electron density of states
79.60.Jv Interfaces; heterostructures; nanostructures
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
81.65.-b Surface treatments
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Electron accumulation layer at n‐Si/non‐liquid electrolyte interfaces

H. Benisty, Ph. Colomban, and J.‐N. Chazalviel

Appl. Phys. Lett. 51, 1121 (1987); http://dx.doi.org/10.1063/1.98759 (3 pages) | Cited 2 times

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n‐Si/non‐liquid electrolyte interfaces have been realized in order to obtain electron accumulation layers of very high concentration at various temperatures. The interface has been characterized by using standard electrochemical measurements and the two‐dimensional electron gas has been studied by transconductance and infrared optical absorption measurements. These interfaces are found to exhibit densities as high as 4×1013 electrons cm−2. These results are compared with available data on analogous n‐Si/organic‐solvent electrolyte interfaces.
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73.40.Mr Semiconductor-electrolyte contacts
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