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28 Jun 1993

Volume 62, Issue 26, pp. 3393-3533

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Observation of the DX center in Pb‐doped GaAs

U. Willke, D. K. Maude, J. M. Sallese, M. L. Fille, B. el Jani, P. Gibart, and J. C. Portal

Appl. Phys. Lett. 62, 3467 (1993); http://dx.doi.org/10.1063/1.109022 (3 pages) | Cited 1 time

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Pb in GaAs introduces a DX center‐like (metastable) defect level that is (229±16) meV above the Γ‐conduction‐band edge, in a similar energetic position to the Si and Sn related DX centers in GaAs. The persistent photoconductivity effect quenches at approximately 50 K, indicating that the barrier to capture for the Pb and Sn dopants are similar. Despite the quite different atomic parameters of the Pb atom compared with the Sn atom, no significant chemical shifts have been found.
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71.55.Eq III-V semiconductors
61.72.uj III-V and II-VI semiconductors
72.20.My Galvanomagnetic and other magnetotransport effects
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Phonon‐induced electron localization and magnetic‐field effects in a double quantum dot

Aiichiro Nakano, Rajiv K. Kalia, and Priya Vashishta

Appl. Phys. Lett. 62, 3470 (1993); http://dx.doi.org/10.1063/1.109023 (3 pages) | Cited 8 times

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Resonant tunneling of an electron through a double quantum dot is studied in the presence of phonon scattering and magnetic field. The coupled time‐dependent Schrödinger equations for an electron and longitudinal‐optical phonons are solved numerically within a mean‐field approximation. Phonon‐induced electron localization is observed. A magnetic field reduces the buildup time of electron probability density in the dots, but increases the decay time associated with the resonant tunneling. Inelastic processes increase the decay time, but their effect on the buildup time depends on the strength of the magnetic field.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
72.20.Dp General theory, scattering mechanisms
72.10.Di Scattering by phonons, magnons, and other nonlocalized excitations

Field‐induced absorption edge merging in tensile strained GaAsP quantum wells

Badri N. Gomatam, Neal G. Anderson, Farid Agahi, Charles F. Musante, and Kei May Lau

Appl. Phys. Lett. 62, 3473 (1993); http://dx.doi.org/10.1063/1.109024 (3 pages) | Cited 3 times

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Field‐induced merging of electron‐to‐light‐hole (e‐lh) and electron‐to‐heavy‐hole (e‐hh) excitonic absorption edges in tensile‐strained quantum wells is demonstrated for the first time. Photocurrent spectra (77 K) of a GaAs0.92P0.08/Al0.37Ga0.63As multiple‐quantum‐well structure embedded in a p‐i‐n diode clearly show reduction and eventual elimination of a zero‐bias ∼7 meV splitting between the e‐lh and e‐hh exciton peaks with increasing reverse bias. The unique ‘‘light‐hole‐up’’ valence subband configuration required for this field‐induced merging is achieved through a combination of tensile strain and quantum‐size effects in the ∼95 Å GaAs0.92P0.08/Al0.37Ga0.63As multiple quantum wells. The ability to control and eliminate the splitting between the e‐lh and e‐hh absorption edges via an applied electric field offers possibilities for improving the performance of electroabsorption modulators.
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71.70.Ej Spin-orbit coupling, Zeeman and Stark splitting, Jahn-Teller effect
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
78.66.Fd III-V semiconductors

Rutherford backscattering analysis of phosphorus gettering of gold and copper

B. Hartiti, M. Hage‐Ali, J. C. Muller, and P. Siffert

Appl. Phys. Lett. 62, 3476 (1993); http://dx.doi.org/10.1063/1.109025 (3 pages) | Cited 1 time

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The extrinsic gettering of Au and Cu by phosphorus diffusion in a classical or rapid thermal furnace has been analyzed by Rutherford backscattering (RBS) measurements. Accumulation of Au and Cu in the phosphorus‐doped region has been clearly evidenced after classical or rapid thermal diffusion of phosphorus from a spin‐on deposited silicon glass source in the temperature range 950–1050 °C for typical durations of 15 min and 25 s, respectively, confirming the existence of classical as well as a rapid thermal gettering effect.
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61.72.Yx Interaction between different crystal defects; gettering effect
61.72.Cc Kinetics of defect formation and annealing

A comparative study of GaN epilayers grown on sapphire and SiC substrates by plasma‐assisted molecular‐beam epitaxy

M. E. Lin, B. Sverdlov, G. L. Zhou, and H. Morkoç

Appl. Phys. Lett. 62, 3479 (1993); http://dx.doi.org/10.1063/1.109026 (3 pages) | Cited 64 times

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We report structural, electrical, and optical data for GaN samples grown on both 6H‐SiC and sapphire substrates. A two‐stage substrate preparation procedure was employed for removing oxygen from 6H‐SiC and c‐plane sapphire substrates without the need for elaborate high‐temperature thermal degassing. Both sapphire and SiC substrates were treated with hydrogen plasma to reduce the surface contamination as evidenced by the observation of sharp (1×1) reconstruction RHEED (reflected high‐energy electrons diffraction) patterns. Thin AlN buffer layers were employed and the crystalline quality of GaN films was studied by temperature‐dependent Hall measurements, photoluminescence, and x‐ray diffraction. Layers with room‐temperature mobilities as high as 580 cm2/V s on SiC substrates were obtained.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
73.61.Ey III-V semiconductors
78.66.Fd III-V semiconductors

Resonant Raman scattering and photoluminescence at the E0 band gap of carbon‐doped AlAs

J. Wagner, A. Fischer, and K. Ploog

Appl. Phys. Lett. 62, 3482 (1993); http://dx.doi.org/10.1063/1.109001 (3 pages) | Cited 11 times

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Carbon‐doped AlAs grown by solid source molecular beam epitaxy has been studied by Raman and photoluminescence spectroscopy. Doping levels exceeding 2×1019 cm−3 have been obtained using a heated graphite filament as the carbon source. For excitation just above the AlAs E0 band‐gap energy radiative recombination is observed across that band gap, which involves nonthermalized photogenerated electrons occupying the Γ‐conduction‐band minimum rather than the lowest indirect X minima. Raman spectra excited in resonance with the E0 band gap show a hole‐plasmon‐longitudinal‐optical‐phonon coupling similar to that found in p‐type GaAs. Resonantly excited Raman spectra further reveal a vibrational mode at ≂635 cm−1, which is assigned to the local vibrational mode of the CAs acceptor in AlAs.
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71.55.Eq III-V semiconductors
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
78.55.Cr III-V semiconductors
78.30.Fs III-V and II-VI semiconductors

Low temperature Si3N4 direct bonding

Robert W. Bower, Mohd S. Ismail, and Brian E. Roberds

Appl. Phys. Lett. 62, 3485 (1993); http://dx.doi.org/10.1063/1.109002 (3 pages) | Cited 26 times

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Extremely strong bonds can be formed between smooth, clean layers of Si3N4 at temperatures ranging between 90 and 300 °C. These bonds have been formed between Si3N4 layers deposited on various substrates with deposition temperatures as low as 300 °C. The bond is initially formed at room temperature and subsequently annealed at temperatures ranging between 90 and 300 °C. Thus, the materials bonded in this manner are never exposed to temperatures higher than 300 °C. This low temperature bond greatly expands the range of applications of direct bonding which had heretofore been restricted by the temperatures of 700 to 1000 °C required by conventional wafer bonding.
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68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
85.40.Hp Lithography, masks and pattern transfer

Impurity induced disordering of CdZnSe/ZnSe strained layer superlattices by germanium diffusion

T. Yokogawa, P. D. Floyd, M. M. Hashemi, J. L. Merz, H. Luo, and J. K. Furdyna

Appl. Phys. Lett. 62, 3488 (1993); http://dx.doi.org/10.1063/1.109003 (3 pages) | Cited 1 time

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We report the first confirmation of disordering of CdZnSe/ZnSe strained layer superlattices (SLSs) by Ge diffusion. Both the as‐grown sample and the sample annealed without a Ge layer showed several orders of well‐resolved double crystal x‐ray satellite peaks due to SLS periodic structure. However, the satellite peaks completely disappeared in the Ge‐diffused sample, indicating that the SLS structure was disordered by the Ge diffusion and not caused by the annealing process. PL measurements at 1.4 K of both the as‐grown and the annealed samples without Ge diffusion show identical, sharp excitonic emission around 483 nm. After Ge diffusion, the PL peaks shift to higher energy confirming the layer disordering of the SLS.
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68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
68.35.Fx Diffusion; interface formation
78.66.Hf II-VI semiconductors

Ultrathin textured polycrystalline oxide with a high electron conduction efficiency prepared by thermal oxidation of thin polycrystalline silicon film on n+ polycrystalline silicon

Shye Lin Wu, Chung Len Lee, and Tan Fu Lei

Appl. Phys. Lett. 62, 3491 (1993); http://dx.doi.org/10.1063/1.109004 (2 pages) | Cited 2 times

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This letter presents an ultrathin textured polycrystalline oxide (polyoxide) (≤100 Å) prepared by thermal oxidation of thin polycrystalline silicon (polysilicon) film on n+ polysilicon. The presented textured polyoxide exhibits a much higher electron injection efficiency, a much smaller electron trapping rate, and a much larger charge to breakdown than the normal polyoxide. The value of Qbd of the textured polyoxide could be more than 3000 C/cm2 even under 100 mA/cm2 stressing.
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81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
68.55.-a Thin film structure and morphology
77.55.-g Dielectric thin films
81.65.-b Surface treatments

Enhancement of laser‐induced defect‐initiated Ga0 emission from GaAs(110) surfaces by Br adsorption

Jun’ichi Kanasaki, Anne Y. Matsuura, Yasuo Nakai, Noriaki Itoh, and R. F. Haglund

Appl. Phys. Lett. 62, 3493 (1993); http://dx.doi.org/10.1063/1.109005 (3 pages) | Cited 2 times

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High sensitivity measurements of Ga emission, produced by laser irradiation of fluences below the ablation threshold, from a Br‐adsorbed GaAs(110) surface were carried out. It was found that bromine adsorption enhances Ga0 emission: the amount of enhancement is linearly proportional to the amount of adsorbates but much smaller in the absolute value. The result is interpreted as a Br‐induced weakening of the Ga—As bond on defect sites by Br adsorption.
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81.65.-b Surface treatments
82.50.Bc Processes caused by infrared radiation
82.50.Hp Processes caused by visible and UV light

Control and characterization of ordering in GaInP

L. C. Su, S. T. Pu, G. B. Stringfellow, J. Christen, H. Selber, and D. Bimberg

Appl. Phys. Lett. 62, 3496 (1993); http://dx.doi.org/10.1063/1.109006 (3 pages) | Cited 39 times

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Ga0.51In0.49P layers have been grown by organometallic vapor phase epitaxy on GaAs substrates with [110]‐oriented grooves on the surface that have an important effect on the formation of Cu‐Pt ordered structures during growth. In this work, the groove shape is demonstrated to be critically important. For the optimum groove shape, single domains of the (111) and (111) variants of the Cu‐Pt ordered structure are formed on the two sides of the groove. Shallow grooves produce large domains on each side of the groove containing small domains of the other variant. For deep grooves, only a single variant is formed on each side of the groove, but the domains are small. For substrates with deep grooves on a GaAs substrate misoriented by 9°, every groove contains large regions of highly ordered and completely disordered material separated by a few micrometers. This allows a direct determination of the effect of ordering on the band gap of the material using cathodoluminescence spectroscopy, allowing the first direct demonstration that ordering reduces the energy band gap of a III/V alloy.
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78.66.Fd III-V semiconductors
81.15.Kk Vapor phase epitaxy; growth from vapor phase
78.60.Hk Cathodoluminescence, ionoluminescence

Effect of germanium implantation on metal‐oxide‐semiconductor avalanche injection

Ta‐Cheng Lin and Donald R. Young

Appl. Phys. Lett. 62, 3499 (1993); http://dx.doi.org/10.1063/1.109007 (2 pages)

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The effect of germanium on the hot electron current of a metal‐oxide‐semiconductor device has been studied by avalanche electron injection from the silicon to the silicon dioxide. Different doses of germanium ranging from 1012 to 1015 atoms/cm2 are implanted into the Si‐SiO2 interface. The ‘‘lucky’’ hot electron population is suppressed by the germanium implantation. We have used the charge‐voltage technique to measure the interface state density. The interface state density increase caused by the Ge implantation is negligible if the dose is lower than 1014 Ge/cm2. Our results show that the Ge implantation is a promising method to solve the hot carrier problem that has become important in submicrometer devices.
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73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
72.20.Ht High-field and nonlinear effects
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping

Investigation of rapid‐thermal‐oxidized porous silicon

K.‐H. Li, C. Tsai, J. C. Campbell, B. K. Hance, and J. M. White

Appl. Phys. Lett. 62, 3501 (1993); http://dx.doi.org/10.1063/1.109008 (3 pages) | Cited 24 times

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We report that the photoluminescence of porous Si that was quenched by low‐temperature thermal annealing was restored by further annealing in an oxygen atmosphere at high temperature (750 °C≤T≤1100 °C). The intensity of the photoluminescence recovered to near the as‐anodized value and the peak wavelength was red shifted by approximately 100 nm. The oxidized porous Si has been found to have lower resistance and higher photoelectric efficiency than as‐anodized material.
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78.55.Hx Other solid inorganic materials
81.40.Tv Optical and dielectric properties related to treatment conditions
73.20.At Surface states, band structure, electron density of states

Two‐color infrared photodetector using GaAs/AlGaAs and strained InGaAs/AlGaAs multiquantum wells

K. L. Tsai, K. H. Chang, C. P. Lee, K. F. Huang, J. S. Tsang, and H. R. Chen

Appl. Phys. Lett. 62, 3504 (1993); http://dx.doi.org/10.1063/1.109009 (3 pages) | Cited 32 times

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A two‐color infrared detector using GaAs/AlGaAs and strained InGaAs/AlGaAs multiquantum wells is demonstrated. The response peak of the GaAs/AlGaAs quantum well is at 8 μm, and that of the InGaAs/AlGaAs quantum well is at 5.3 μm. The responsivity of the detector is 1 A/W at 8 μm and 0.27 A/W at 5.3 μm; these are the best values reported for a two‐color quantum well infrared detectors (QWIPs) with peak sensitivities in the spectral regions of 3–5.3 μm and 7.5–14 μm. Single‐colored 5.3 and 8 μm QWIPs were also fabricated to study the bias dependent behavior. This behavior can be explained using the concept of current continuity. Because of a higher electrical resistance, a high electric field domain is always formed first in the shorter wavelength quantum well stack.
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85.60.Gz Photodetectors (including infrared and CCD detectors)
78.66.Fd III-V semiconductors
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Hot electron dynamics study by terahertz radiation from large aperture GaAs p‐i‐n diodes

L. Xu, B. B. Hu, W. Xin, D. H. Auston, and J. D. Morse

Appl. Phys. Lett. 62, 3507 (1993); http://dx.doi.org/10.1063/1.109010 (3 pages) | Cited 3 times

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Subpicosecond electromagnetic pulses having tetrahertz (THz) bandwidths have been generated from large aperture GaAs p‐i‐n diodes under bias by illumination with femtosecond optical pulses. The amplitude and shape of the radiated pulses change with the applied bias and the wavelength of the optical pulses illuminating the p‐i‐n diode. Comparing this radiation with THz radiation from large aperture Si p‐i‐n diodes provides evidence of velocity overshoot in the transient response of optically injected electrons in GaAs.
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72.20.Ht High-field and nonlinear effects
72.40.+w Photoconduction and photovoltaic effects
78.47.-p Spectroscopy of solid state dynamics

Optical response of an ultrathin film and a large‐angle grain‐boundary in superconducting YBa2Cu3O7−δ

S. Bhattacharya, X. X. Xi, M. Rajeswari, C. Kwon, S. N. Mao, Qi Li, and T. Venkatesan

Appl. Phys. Lett. 62, 3510 (1993); http://dx.doi.org/10.1063/1.109011 (3 pages) | Cited 11 times

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We have investigated the optical response of epitaxial ultrathin (3 nm) YBa2Cu3O7−δ film on NdGaO3 substrate and thin (50 nm) film of YBa2Cu3O7−δ on a bicrystal SrTiO3 substrate. While the current‐voltage characteristics of the ultrathin film indicate a Kosterlitz–Thouless transition (associated with vortex–antivortex unbinding) at a temperature TKT, we do not observe any optical response at or below TKT. An enhanced optical response with nonbolometric characteristics was observed from the grain‐boundary as compared to the bolometric optical response of the epitaxial film at the resistive transition. These results indicate that the grain‐boundary weak links play a significant role in the enhanced optical response near Tc.
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74.25.N- Response to electromagnetic fields
74.50.+r Tunneling phenomena; Josephson effects
74.25.Uv Vortex phases (includes vortex lattices, vortex liquids, and vortex glasses)
74.78.-w Superconducting films and low-dimensional structures

Unexpected time dependence of ac losses in multifilamentary NbTi superconductors

Curt Schmidt

Appl. Phys. Lett. 62, 3513 (1993); http://dx.doi.org/10.1063/1.109012 (3 pages) | Cited 1 time

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Losses of NbTi multifilament superconductors in a copper matrix in alternating magnetic fields were measured using a specially developed sensitive calorimetric method. The investigated samples have filament diameters in the micrometer range and exhibit a strong proximity effect. The measured losses at fixed ac frequency and field amplitude showed an unexpected time dependence on a very long time scale of hours, compared to the ac field cycle time, which was in the millisecond range. This time dependence is probably a consequence of slowly decaying proximity currents.
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74.25.N- Response to electromagnetic fields
74.50.+r Tunneling phenomena; Josephson effects
74.70.Ad Metals; alloys and binary compounds (including A15, MgB2, etc.)

Effect of oxidizing activity on the low‐temperature growth of HoBa2Cu3Ox thin films

Akira Tsukamoto, Masahiko Hiratani, and Shoichi Akamatsu

Appl. Phys. Lett. 62, 3516 (1993); http://dx.doi.org/10.1063/1.109013 (3 pages) | Cited 1 time

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The effect of oxygen plasma on the growth of HoBa2Cu3Ox thin films is investigated. Lowering the growth temperature introduces excess oxygen vacancies, which are formed in a nonequilibrium state regardless of whether the plasma is applied. At growth temperatures as low as 500 °C, the crystallinity of thin films grown in molecular oxygen is superior to that of films grown in oxygen plasma, since the growth conditions close to the decomposition line of the 123 compound enhance the surface migration. At temperatures above 540 °C, no significant difference can be seen between films grown in molecular oxygen and those grown in oxygen plasma. This is thought to be because, at higher temperatures, thin‐film growth is dominated by the thermal energy supplied from the heated substrate.
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81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
74.78.-w Superconducting films and low-dimensional structures
68.55.-a Thin film structure and morphology
74.72.-h Cuprate superconductors

Quasiparticle‐tuned superconducting mixer

N. G. Ugras, A. H. Worsham, D. Winkler, and D. E. Prober

Appl. Phys. Lett. 62, 3519 (1993); http://dx.doi.org/10.1063/1.109604 (3 pages) | Cited 2 times

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We have successfully employed the recently observed quasiparticle admittance of a superconducting tunnel junction as the tuning element for a superconductor‐ insulator‐superconductor mixer. This is the first demonstration of an electronic on‐chip tuning element for a superconducting detector. We observe an increase in the dynamic resistance and an improvement in mixer gain and noise temperature as the dc bias voltage of the tuning junction array is varied. We compare our results with the quantum theory of mixing.
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85.25.Qc Superconducting surface acoustic wave devices and other superconducting devices
84.40.Dc Microwave circuits
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
95.55.-n Astronomical and space-research instrumentation

Large critical currents and improved epitaxy of laser ablated Ag‐doped YBa2Cu3O7−δ thin films

Dhananjay Kumar, M. Sharon, R. Pinto, P. R. Apte, S. P. Pai, S. C. Purandare, L. C. Gupta, and R. Vijayaraghavan

Appl. Phys. Lett. 62, 3522 (1993); http://dx.doi.org/10.1063/1.109014 (3 pages) | Cited 51 times

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Microstructure and critical current densities of laser ablated YBa2Cu3O7−δ thin films doped with 2–20 wt. % Ag have been studied. A critical current density as high as 1.4×107 A cm−2 at 77 K has been realized on 〈100〉 SrTiO3 substrates with YBaCuO films doped with 5 wt. % Ag which has been found to be the optimum. Evidence indicates that the improved microstructure and epitaxy which is a consequence of grain enlargement and alignment caused by Ag is responsible for the high values of critical currents observed.
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74.25.Sv Critical currents
74.78.-w Superconducting films and low-dimensional structures
74.72.-h Cuprate superconductors
81.15.Fg Pulsed laser ablation deposition

(Ni80Co20/Cu) multilayers: Giant magnetoresistance with low saturation field

X. Bian, J. O. Ström‐Olsen, Z. Altounian, Y. Huai, and R. W. Cochrane

Appl. Phys. Lett. 62, 3525 (1993); http://dx.doi.org/10.1063/1.109015 (3 pages) | Cited 12 times

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We have observed giant magnetoresistance (MR) in Ni80Co20/Cu multilayers. Saturation magnetoresistance exceeding 16% and very well‐defined oscillations in MR as a function of Cu spacer thickness are observed at room temperature with an oscillation period and phase quite similar to that found in other Cu‐based multilayered systems. Of particular interest are the small saturation fields (HS<120 Oe) for Cu thickness near the second peak (∼20 Å) which result in large MR field sensitivities up to 0.12%/Oe at room temperature.
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75.70.-i Magnetic properties of thin films, surfaces, and interfaces
72.15.Gd Galvanomagnetic and other magnetotransport effects

Synthesis of Nd(FeTi)12 films by sputtering

I. Panagiotopoulos, D. Wang, D. Niarchos, and D. J. Sellmyer

Appl. Phys. Lett. 62, 3528 (1993); http://dx.doi.org/10.1063/1.109016 (3 pages) | Cited 3 times

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Nd(FeTi)12 films have been synthesized by dc magnetron sputtering. The films have tetragonal ThMn12 crystal structure as confirmed by XRD and magnetic measurements. The lattice parameters are a=8.57 and c=4.801 Å. The degree of the ThMn12 phase formation and the texture of the films are found to be dependent on deposition parameters. The films can be aligned with the (001) basal plane in the film plane by suitable deposition conditions. Thus the films are textured so that the easy axis, which is the c‐axis, is perpendicular to the film plane. After nitrogenation, the tetragonal ThMn12 crystal structure is retained and the lattice parameters increase to a=8.67 and c=4.862 Å, corresponding to a volume expansion of 3.6%. The coercivity also increases upon nitrogenation.
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81.15.Cd Deposition by sputtering
75.70.-i Magnetic properties of thin films, surfaces, and interfaces
75.50.Bb Fe and its alloys

Self‐assembled alkane monolayers on MoSe2 and MoS2

S. Cincotti and J. P. Rabe

Appl. Phys. Lett. 62, 3531 (1993); http://dx.doi.org/10.1063/1.109017 (3 pages) | Cited 31 times

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Highly ordered monolayers of a long‐chain molecule, dotriacontane (C32H66), have been obtained by self‐assembly at the interface between an organic solution and the basal planes of two semiconductors, MoSe2 and MoS2. Scanning tunneling microscopy in situ at the solid–fluid interfaces revealed that the adsorbate lattices are close packed and oriented relative to the substrate lattices, but that they are not simply commensurate. The results indicate that for flexible chain molecules, which interact only weakly with the surface of a solid substrate, a high degree of order in the adsorbed monolayers is induced by the atomical flatness of the substrate, while the coincidence of lattice parameters and the specific surface chemistry play only a minor role. Details of the packing, including the symmetry of the adsorbate unit cell, depend on the particular substrate. The results imply that atomical flatness is a key factor for the fabrication of highly ordered organic/inorganic heterostructures.
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81.15.Lm Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids)
68.08.-p Liquid-solid interfaces
68.43.-h Chemisorption/physisorption: adsorbates on surfaces
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