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18 Dec 1995

Volume 67, Issue 25, pp. 3673-3818

Page 2 of 2 Pages Previous Page | Jump to Page

Surface photoabsorption studies of the chemical structure of GaInP grown by organometallic vapor phase epitaxy

H. Murata, I. H. Ho, T. C. Hsu, and G. B. Stringfellow

Appl. Phys. Lett. 67, 3747 (1995); http://dx.doi.org/10.1063/1.115370 (3 pages) | Cited 19 times

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The surface structure of Ga0.52In0.48P was studied by surface photoabsorption. An absorption peak due to P dimers on Ga0.52In0.48P was observed at ∼400 nm, shorter than for InP (430 nm). From comparison with results for GaAs and InP, the data are interpreted to indicate that at a tertiarybutylphosphine (TBP) pressure of 50 Pa for temperatures below 670 °C, the P‐stabilized surface has P dimers aligned along the [110] direction, i.e., it has a (2×4)‐like structure. Above 670 °C, the 400 nm peak due to the P‐dimer structure disappears because of P desorption from the surface at this TBP partial pressure. Epitaxial Ga0.52In0.48P layers grown using TBP, trimethylgallium and ethyldimethylindium are nearly disordered at 670 °C and highly ordered at 620 °C. These data suggest a correlation between surface structure and ordering. © 1995 American Institute of Physics.
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68.35.B- Structure of clean surfaces (and surface reconstruction)
81.15.Kk Vapor phase epitaxy; growth from vapor phase
78.66.Fd III-V semiconductors

Addition of N2 as a polymer deposition inhibitor in CH4/H2 electrocyclotron resonance plasma etching of Hg1−xCdxTe

Robert C. Keller, M. Seelmann‐Eggebert, and H. J. Richter

Appl. Phys. Lett. 67, 3750 (1995); http://dx.doi.org/10.1063/1.115371 (3 pages) | Cited 14 times

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An approach is presented which eliminates the problems caused by hydrocarbon polymer deposition in etching compound semiconductor with CH4/H2 based plasmas. We find that atomic nitrogen, created by the addition of N2 to the plasma, inhibits polymer deposition in the chamber and on the sample. Atomic nitrogen has several beneficial effects; the elimination of polymer precursors, the reduction of the atomic hydrogen concentration, and a potential increase of methyl radical concentration. It is also demonstrated that the addition of N2 to CH4/H2 based electrocyclotron resonance plasmas used to etch HgCdTe eliminates the roughness normally formed during etching. © 1995 American Institute of Physics.
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81.65.-b Surface treatments
82.33.Xj Plasma reactions (including flowing afterglow and electric discharges)

Wide bandwidth AlAs/AlGaAs tandem Bragg reflectors grown by organometallic vapor phase epitaxy

W. I. Lee

Appl. Phys. Lett. 67, 3753 (1995); http://dx.doi.org/10.1063/1.115372 (3 pages) | Cited 2 times

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Wide bandwidth AlAs/Al0.6Ga0.4As tandem Bragg reflectors were grown by organometallic vapor phase epitaxy. Quarter‐wave reflector stacks designed for different wavelengths were placed in cascade in epitaxially grown structures to expand the high reflectance bands. Intermediate low‐index layers were put in between every two stacks to suppress the transmission peaks in the centers of the combined high reflectance bands. While a single‐stack structure showed a full width half‐maximum bandwidth of 500 Å, the two‐stack and the three‐stack structures effectively doubled and tripled this bandwidth to approximately 1000 and 1500 Å, respectively. © 1995 American Institute of Physics.
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42.79.Fm Reflectors, beam splitters, and deflectors
81.15.Kk Vapor phase epitaxy; growth from vapor phase
78.66.Fd III-V semiconductors

Femtosecond carrier dynamics in low‐temperature grown Ga0.51In0.49P

Y. Kostoulas, K. B. Ucer, G. W. Wicks, and P. M. Fauchet

Appl. Phys. Lett. 67, 3756 (1995); http://dx.doi.org/10.1063/1.115373 (3 pages) | Cited 6 times

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Pump‐probe spectroscopy is used to determine the dynamics of carriers in thin films of Ga0.51In0.49P grown at temperatures of 500, 300, and 200 °C. The carrier trapping time τtr, is found to be ∼0.2 ps for the 200 °C sample and ∼0.9 ps for the 300 °C sample. Annealing of the 200 °C sample at 450 °C for 10 min causes the optical response to slow appreciably (τtr∼0.7 ps), indicating that the point defects are directly responsible for the ultrashort optical response observed in this material. © 1995 American Institute of Physics.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
78.47.-p Spectroscopy of solid state dynamics
78.66.Fd III-V semiconductors

Temperature‐mediated phase selection during growth of GaN on (111)A and (111)B GaAs substrates

J. W. Yang, J. N. Kuznia, Q. C. Chen, M. Asif Khan, T. George, M. De Graef, and S. Mahajan

Appl. Phys. Lett. 67, 3759 (1995); http://dx.doi.org/10.1063/1.115374 (3 pages) | Cited 24 times

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GaN layers having the zinc blende and wurtzite structures can be selectively deposited on (111)A and (111)B GaAs substrates by varying the growth temperature. Using the growth temperature as a variable, layers having the two structures have been sequentially deposited. The as‐grown structures have been examined by cross‐sectional high resolution electron microscopy. Results indicate that the two phases once formed are structurally stable in the temperature range examined. Furthermore, the transition from GaN (zinc blende) to GaN (wurtzite) is sharp, whereas a faulted region is observed during the reverse transition. Arguments have been developed to rationalize these observations. © 1995 American Institute of Physics.
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68.55.Nq Composition and phase identification
81.15.Jj Ion and electron beam-assisted deposition; ion plating

A compensating donor with a binding energy of 57 meV in nitrogen‐doped ZnSe

Ziqiang Zhu, Glen D. Brownlie, Paul J. Thompson, Kevin A. Prior, and Brian C. Cavenett

Appl. Phys. Lett. 67, 3762 (1995); http://dx.doi.org/10.1063/1.115375 (3 pages) | Cited 18 times

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A compensating deep donor with a binding energy of 57 meV in ZnSe:N epilayers has been studied by means of photoluminescence and selectively excited photoluminescence (SPL) spectroscopy. The emission of 2.766 eV due to transitions between the deep donors and free holes (DdF) was observed at 4 K under strong excitation conditions. The emission at 2.681 eV due to transitions between deep donors and nitrogen acceptors (DdAP) is attributed to the same deep donor as that of the DdF emission through a detailed SPL study. It is also demonstrated that the SPL technique is important for studying the deep levels in ZnSe:N. © 1995 American Institute of Physics.
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71.55.Gs II-VI semiconductors
78.66.Hf II-VI semiconductors

Electric field induced interband second harmonic generation in GaAs/AlGaAs quantum wells

A. Fiore, E. Rosencher, V. Berger, and J. Nagle

Appl. Phys. Lett. 67, 3765 (1995); http://dx.doi.org/10.1063/1.115376 (3 pages) | Cited 12 times

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We investigate the second order optical susceptibility χ(2) of symmetric GaAs/AlGaAs quantum wells under applied bias, in the frequency region near half the band gap. The second harmonic is generated in a transmission geometry, and is separated from bulk contribution by a lock‐in detection technique. As opposed to previous reports, we find that χxzx(2) is much higher than χzxx(2). For 50 Å quantum wells, χxzx(2)≊25 pm/V and χzxx(2)≊0 at λ=1.66 μm under an applied electric field E=50 kV/cm. © 1995 American Institute of Physics.
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42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.66.Fd III-V semiconductors

Self‐organized InP islands on (100) GaAs by metalorganic vapor phase epitaxy

M. Sopanen, H. Lipsanen, and J. Ahopelto

Appl. Phys. Lett. 67, 3768 (1995); http://dx.doi.org/10.1063/1.115377 (3 pages) | Cited 31 times

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The effect of growth temperature, deposition rate, and substrate misorientation angle on size, density, and uniformity of InP islands grown on (100) GaAs by metalorganic vapor phase epitaxy is investigated. The density of InP islands is observed to remain constant as a function of growth temperature in the temperature range of 620–680 °C. Below 620 °C the island density increases with decreasing temperature. Above 605 °C a subset of islands having a uniform size is observed. The degree of uniformity depends largely on the deposition rate and the size of the uniform islands on the growth temperature. © 1995 American Institute of Physics.
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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
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Real and reciprocal space mapping of the mosaic dispersion in self‐nucleated AlxGa1−xN thin films on (00.1) sapphire

T. J. Kistenmacher, D. K. Wickenden, M. E. Hawley, and R. P. Leavitt

Appl. Phys. Lett. 67, 3771 (1995); http://dx.doi.org/10.1063/1.115378 (3 pages) | Cited 3 times

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Measures of the mosaic dispersion of a series of self‐nucleated AlxGa1−xN thin films, grown by low‐pressure metalorganic chemical vapor deposition in a nitrogen carrier gas, have been accumulated by a combination of reciprocal space x‐ray scattering patterns and real space images from scanning tunneling and atomic force microscopies. The films are shown to be dense mosaics of highly oriented islands whose in‐plane and out‐of‐plane orientational coherence and in‐plane island size decrease with increasing x. The highly correlated reductions in island size and orientational coherence are believed to be attributable to a decrease in surface mobility of reactants, which is independent of nucleation layer or carrier gas. © 1995 American Institute of Physics.
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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
68.55.-a Thin film structure and morphology
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Molecular beam epitaxy growth method for vertical‐cavity surface‐emitting laser resonators based on substrate thermal emission

J. J. Talghader, M. A. Hadley, and J. S. Smith

Appl. Phys. Lett. 67, 3774 (1995); http://dx.doi.org/10.1063/1.115379 (3 pages)

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A molecular beam epitaxy growth monitoring method is developed for distributed Bragg reflectors and vertical‐cavity surface‐emitting laser (VCSEL) resonators. The wavelength of the substrate thermal emission that corresponds to the optical cavity resonant wavelength is selected by a monochromator and monitored during growth. This method allows VCSEL cavities of arbitrary design wavelength to be grown with a single control program. This letter also presents a theoretical model for the technique which is based on transmission matrices and simple thermal emission properties. Demonstrated reproducibility of the method is well within 0.1%. © 1995 American Institute of Physics.
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42.55.Px Semiconductor lasers; laser diodes
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Damage‐induced luminescence in InP

T. Sekiguchi and H. S. Leipner

Appl. Phys. Lett. 67, 3777 (1995); http://dx.doi.org/10.1063/1.115380 (3 pages) | Cited 4 times

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Optical properties of scratched InP specimens were studied by means of cathodoluminescence (CL). A new luminescence band around 942 nm (S1) was detected in the vicinity of scratches. The S1 band is composed of two peaks at 938 and 946 nm. Monochromatic CL images showed that the S1 luminescence is constrained to regions of high residual strain and not related to dislocations or cracks. The S1 intensity increased in samples with a higher Fe content. S1 vanished after 450 K annealing. © 1995 American Institute of Physics.
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61.72.Hh Indirect evidence of dislocations and other defects (resistivity, slip, creep, strains, internal friction, EPR, NMR, etc.)
78.60.Hk Cathodoluminescence, ionoluminescence

Calculation of gain‐current characteristics in ZnCdSe‐ZnSe quantum well structures including many body effects

P. Rees, F. P. Logue, J. F. Donegan, J. F. Heffernan, C. Jordan, and J. Hegarty

Appl. Phys. Lett. 67, 3780 (1995); http://dx.doi.org/10.1063/1.115381 (3 pages) | Cited 10 times

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The gain‐spontaneous recombination characteristics have been calculated for a 40 Å Zn0.8Cd0.2Se‐ZnSe quantum well including many body effects. We examine the effect of the inclusion of the Coulomb enhancement on the gain spectra and the gain‐current relationship. We show that, in the absence of the Coulomb enhancement, the threshold current density of a 340 μm 40 Å Zn0.8Cd0.2Se‐ZnSe quantum well laser is underestimated by approximately 40% and the lasing wavelength overestimated by 4 nm. Our calculation of the scattering lifetime for the first electron‐heavy hole transition gives a lifetime varying between 29 and 37 fs, and shows that the carrier‐phonon scattering mechanism in II‐VI quantum wells is more dominant than in III‐V materials. We also comment on the effect the neglect of Coulomb enhancement has on the calculation of leakage currents in a laser at threshold. © 1995 American Institute of Physics.
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42.55.Px Semiconductor lasers; laser diodes
71.35.-y Excitons and related phenomena
73.50.Bk General theory, scattering mechanisms
78.66.Hf II-VI semiconductors

Growth oscillations with monolayer periodicity monitored by ellipsometry during metalorganic vapor phase epitaxy of GaAs(001)

J.‐T. Zettler, T. Wethkamp, M. Zorn, M. Pristovsek, C. Meyne, K. Ploska, and W. Richter

Appl. Phys. Lett. 67, 3783 (1995); http://dx.doi.org/10.1063/1.115382 (3 pages) | Cited 18 times

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In this letter we report on the observation of growth oscillations with monolayer periodicity by ellipsometry. An oscillation amplitude of δ〈ε1〉=0.05 was measured using an optimized spectroscopic in situ ellipsometer whose wavelength was tuned to the 2.65 eV resonance energy of the arsenic dimers covering the GaAs (001) growth surface. The monolayer periodicity was verified by parallel monitoring of the growth with reflectance anisotropy spectroscopy (RAS). © 1995 American Institute of Physics.  
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
78.66.Fd III-V semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Effect of Cl incorporation on the stability of hydrogenated amorphous silicon

Jae Seong Byun, Hong Bin Jeon, Kyung Ha Lee, and Jin Jang

Appl. Phys. Lett. 67, 3786 (1995); http://dx.doi.org/10.1063/1.115383 (3 pages) | Cited 11 times

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Hydrogenated amorphous silicon (a‐Si:H) films were prepared by remote plasma chemical vapor deposition (RPCVD) using SiH4/SiH2Cl2/He/H2 mixtures. With increasing Cl content in a‐Si:H up to about 1019 cm−3, the stablity of photoconductivity under light illumination was improved with keeping the defect density and Urbach energy constant. We deposited hydrogenated amorphous silicon films with hydrogen content of 6 at. %, Cl content of ∼1019 cm−3, and defect density of 3×1015 cm−3, which exhibited very small photoconductivity degradation under light illumination. The optimum Cl concentration in a‐Si:H for stable a‐Si:H appears to be ∼1019 cm−3. © 1995 American Institute of Physics.
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73.50.Pz Photoconduction and photovoltaic effects
73.61.Jc Amorphous semiconductors; glasses

Effect of multiplication layer width on breakdown voltage in InP/InGaAs avalanche photodiode

Chan‐Yong Park, Kyung‐Sook Hyun, Seung‐Goo Kang, and Hong‐Man Kim

Appl. Phys. Lett. 67, 3789 (1995); http://dx.doi.org/10.1063/1.115384 (3 pages) | Cited 2 times

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Breakdown voltages of InP/InGaAs avalanche photodiodes have been analyzed with structure parameters, such as multiplication layer width (MLW) and absorption layer thickness. It is shown that there exists a critical MLW, w0, where the breakdown voltage is the lowest. As MLW increases, the breakdown voltage increases slowly in the region of MLW≥w0 while the breakdown voltage decreases in the region of MLW≤w0. It is also revealed that w0 is a function of absorption layer thickness. The measured breakdown voltages having MLWs of 0.15–0.4 μm were reported and compared to the calculated ones, which agreed very well with each other. © 1995 American Institute of Physics.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
85.60.Dw Photodiodes; phototransistors; photoresistors

Kinetics of photoconductivity in n‐type GaN photodetector

P. Kung, X. Zhang, D. Walker, A. Saxler, J. Piotrowski, A. Rogalski, and M. Razeghi

Appl. Phys. Lett. 67, 3792 (1995); http://dx.doi.org/10.1063/1.115385 (3 pages) | Cited 35 times

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High‐quality ultraviolet photoconductive detectors have been fabricated using GaN layers grown by low‐pressure metalorganic chemical vapor deposition on (11⋅0) sapphire substrates. The spectral responsivity remained nearly constant for wavelengths from 200 to 365 nm and dropped sharply by almost three orders of magnitude for wavelengths longer than 365 nm. The kinetics of the photoconductivity have been studied by the measurements of the frequency‐dependent photoresponse and photoconductivity decay. Strongly sublinear response and excitation‐dependent response time have been observed even at relatively low excitation levels. This can be attributed to redistribution of the charge carriers with increased excitation level. © 1995 American Institute of Physics.
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73.61.Ey III-V semiconductors
85.60.Gz Photodetectors (including infrared and CCD detectors)

1.3 μm photoluminescence from InGaAs quantum dots on GaAs

R. P. Mirin, J. P. Ibbetson, K. Nishi, A. C. Gossard, and J. E. Bowers

Appl. Phys. Lett. 67, 3795 (1995); http://dx.doi.org/10.1063/1.115386 (3 pages) | Cited 131 times

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We use molecular beam epitaxy to grown coherently strained InGaAs islands on (100) GaAs substrates. The islands show room‐temperature photoluminescence at 1.3 μm with a full width at half‐maximum of only 28 meV. The integrated photoluminescence intensity is comparable to that of a quantum well. The islands are formed by depositing 22 monolayers of In0.3Ga0.7As with alternating beams of In, Ga, and As2. Atomic force microscopy measurements show that the islands are ellipsoidal sections with an average peak height of 24 nm. The intersection of the islands with the (100) plane is an ellipse whose major axis is along [011] and has a mean length of 54 nm, and whose minor axis is along [011] and has a mean length of 36 nm. The islands form a dense array with an areal coverage of about 40%. © 1995 American Institute of Physics.
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78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors

Towards realization of a delta‐BSF solar cell: Infrared improvements

Z. T. Kuznicki, J.‐J. Grob, and L. Wu

Appl. Phys. Lett. 67, 3798 (1995); http://dx.doi.org/10.1063/1.115387 (3 pages) | Cited 3 times

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Our previous modeling and simulation demonstrated that a considerable increase in Si single‐crystal back surface field (BSF) solar cell performance is possible by modifications to give a so‐called delta‐BSF device. In our first measurements a widened absorption (up to λ≤3200 nm) and infrared photoconductivity (where the upper wavelength limit λ≤1900 nm was imposed by the emitting lamp) have been observed. © 1995 American Institute of Physics.
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72.40.+w Photoconduction and photovoltaic effects
84.60.Jt Photoelectric conversion

Laser‐induced modification of transport properties of Y–Ba–Cu–O step‐edge weak links

R. Adam, W. Kula, Roman Sobolewski, J. M. Murduck, and C. Pettiette‐Hall

Appl. Phys. Lett. 67, 3801 (1995); http://dx.doi.org/10.1063/1.115388 (3 pages) | Cited 8 times

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We report on the laser‐induced permanent changes of the critical current (Ic) and normal resistance (Rn) of YBa2Cu3O7−x (YBCO) step‐edge Josephson junctions. The 2‐ to 20‐μm‐wide junctions were prepared from a 200‐nm‐thick YBCO film deposited by a pulsed KrF excimer laser onto 300‐nm‐high steps etched in the LaAlO3 substrate. The laser modification experiments were performed by illuminating the junctions at 50 K with a focused Ar‐ion laser beam of various intensities. Depending on the illumination power density, either increase or decrease of the junction Ic has been observed. In particular, after illumination at the 0.6×105 W/cm2 power level, a 75% enhancement of Ic and increase of the IcRn product up to 25% were obtained without a measurable change in the junction critical temperature. The laser‐induced modifications were very reproducible and remained unchanged even after a subsequent room‐temperature/helium thermal cycling of the sample. Photoassisted, thermally activated oxygen redistribution in the YBCO grain boundary region is proposed to explain the observed behavior. © 1995 American Institute of Physics.
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74.25.Sv Critical currents
74.78.-w Superconducting films and low-dimensional structures
74.81.-g Inhomogeneous superconductors and superconducting systems, including electronic inhomogeneities
85.25.Cp Josephson devices

Mechanochemical synthesis of ultrafine Fe powder

J. Ding, W. F. Miao, P. G. McCormick, and R. Street

Appl. Phys. Lett. 67, 3804 (1995); http://dx.doi.org/10.1063/1.115389 (3 pages) | Cited 63 times

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Ultrafine Fe powders were synthesized by mechanochemical solid‐state reduction of FeCl3 by Na and subsequent removal of the reaction by‐products. X‐ray diffraction, Mössbauer spectroscopy, and transmission electron microscopy measurements showed that Fe particles with a relatively uniform particle size ∼10 nm were formed during the mechanical milling process. The powders exhibited coercivity values of 350–550 Oe, consistent with that expected for separated nanosized particles. This study demonstrates that mechanochemical processing has significant potential for the synthesis of ultrafine metal powders in an economic and efficient way. © 1995 American Institute of Physics.
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75.50.Bb Fe and its alloys
81.20.-n Methods of materials synthesis and materials processing
81.05.Rm Porous materials; granular materials

Slowing the oxidation of Cu in Cu–Co nanocrystals by Co surface passivation

F. H. Kaatz, V. G. Harris, L. Kurihara, D. R. Rolison, and A. S. Edelstein

Appl. Phys. Lett. 67, 3807 (1995); http://dx.doi.org/10.1063/1.115390 (3 pages) | Cited 3 times

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Heating chemically prepared nanocrystals of Cu80Co20 causes Co to precipitate preferentially on the surface of the Cu nanocrystals. X‐ray diffraction and x‐ray photoelectron spectroscopies show that the Co significantly retards the oxidation of the Cu nanocrystals. © 1995 American Institute of Physics.
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81.05.Bx Metals, semimetals, and alloys
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

Femtosecond demodulation source for high‐resolution submillimeter spectroscopy

Thomas M. Goyette, Wei Guo, Frank C. De Lucia, John C. Swartz, Henry O. Everitt, B. D. Guenther, and Elliott R. Brown

Appl. Phys. Lett. 67, 3810 (1995); http://dx.doi.org/10.1063/1.115391 (3 pages) | Cited 11 times

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A new continuously tunable submillimeter source for spectroscopy and other high‐resolution applications has been developed. In this source the optical spectrum of a mode‐locked femtosecond laser is downconverted into the submillimeter region by the demodulation process of a photoconductive switch. The power generated is subsequently radiated into free space by an antenna which is integrated along with the switch on low‐temperature grown GaAs. The very high resolution is ultimately traceable to the cavity length of the laser and the stable mode‐lock frequency which results. Among the most important attributes of the sources are straightforward absolute frequency calibration, very high spectral purity, and the potential for spectral multiplexing. © 1995 American Institute of Physics.
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42.65.-k Nonlinear optics
42.72.Ai Infrared sources
42.79.Nv Optical frequency converters

Compensation of the temperature coefficient of the dielectric constant of barium strontium titanate

R. J. Cava, W. F. Peck, J. J. Krajewski, and D. A. Fleming

Appl. Phys. Lett. 67, 3813 (1995); http://dx.doi.org/10.1063/1.115392 (3 pages) | Cited 4 times

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We report a significant decrease in the temperature coefficient of the dielectric constant (TCK) for polycrystalline ceramics of barium–strontium–titanate through admixture with tetragonal bronze‐type barium strontium niobate. For Ba0.5Sr0.5TiO3 ceramics, a 10% admixture of the niobate decreases TCK by a factor of 2.5 at 10 MHz, with negligible degradation of the dielectric loss; a 37.5% admixture decreases TCK by a factor of more than 100. Dielectric constants for the mixtures are in the range of 200–500. © 1995 American Institute of Physics.
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77.22.Ch Permittivity (dielectric function)
77.84.Bw Elements, oxides, nitrides, borides, carbides, chalcogenides, etc.
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates

Improved atomic force microscopy imaging using carbon‐coated probe tips

Bruce B. Doris and Rama I. Hegde

Appl. Phys. Lett. 67, 3816 (1995); http://dx.doi.org/10.1063/1.115393 (3 pages) | Cited 5 times

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Atomic force microscopy (AFM) images using carbon‐coated probe tips are presented for hydrogen‐passivated Si and SiO2 surfaces. Tapping mode measurements on these surfaces demonstrate that the image quality and probe tip wear characteristics are dramatically improved for scans performed with the carbon coated tips. The reasons for the improved quality of AFM imaging and reduced tip damage are discussed. © 1995 American Institute of Physics.
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07.79.Lh Atomic force microscopes
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
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