APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

14 Nov 1994

Volume 65, Issue 20, pp. 2507-2614

Page 1 of 2 Pages Next Page | Jump to Page

Photoactivated birefringence in antiferroelectric thin films via a structural transition

Feiling Wang, Kewen K. Li, and Gene H. Haertling

Appl. Phys. Lett. 65, 2507 (1994); http://dx.doi.org/10.1063/1.112618 (3 pages) | Cited 1 time

Full Text: | Download PDF

Show Abstract
A photoactivated birefringence has been observed in an antiferroelectric lead zirconate titanate (PZT) thin film material bounded by an indium‐tin oxide (ITO) electrode. This phenomenon stemmed from the ultraviolet (UV) assistance to an antiferroelectric‐to‐ferroelectric structural transition which otherwise was inhibited by an effect of the lead zirconate titanate (PZT)‐ITO interface. The UV‐assisted structural transition was accompanied by a significant change in the birefringence of the PZT thin films. Using this phenomenon, an UV‐addressed visible‐light modulation was demonstrated with an ITO/PZT/Pt thin film structure on silicon substrates. © 1994 American Institute of Physics.
Show PACS
77.80.B- Phase transitions and Curie point
78.20.Fm Birefringence
42.40.Eq Holographic optical elements; holographic gratings

Current injection GaAs/AlGaAs quantum wire lasers fabricated by cleaved edge overgrowth

Werner Wegscheider, Loren Pfeiffer, Kenneth West, and Ronald E. Leibenguth

Appl. Phys. Lett. 65, 2510 (1994); http://dx.doi.org/10.1063/1.112619 (3 pages) | Cited 41 times

Full Text: | Download PDF

Show Abstract
We report the operation of quantum wire (QWR) semiconductor diode lasers fabricated by cleaved edge overgrowth. The active region in these index guided lasers consists of 15 QWRs formed at the right angle intersection of 15 [001] oriented quantum wells (QWs) each 7 nm wide, with a single 7‐nm‐wide QW grown along the [110] direction. Doping with Be and Si in the two orthogonal growth directions leads to the formation of a linear p‐n junction in which the QWRs are embedded. Efficient current injection into the wires is demonstrated by the almost complete suppression of optical emission from QW states as well as by threshold currents as low as 0.4 mA for uncoated devices at 4.2 K. © 1994 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.-v Laser optical systems: design and operation

Temporal magnification and reversal of 100 Gb/s optical data with an up‐conversion time microscope

C. V. Bennett, R. P. Scott, and B. H. Kolner

Appl. Phys. Lett. 65, 2513 (1994); http://dx.doi.org/10.1063/1.112620 (3 pages) | Cited 34 times

Full Text: | Download PDF

Show Abstract
We have developed an up‐conversion time microscope capable of expanding ultrafast optical wave forms to a time scale accessible to ordinary sampling oscilloscopes. In this system, a 100 Gb/s optical word is magnified (slowed down) to a rate of 8.55 Gb/s with a time lens placed between two dispersive delay lines. The time lens is a nonlinear crystal which mixes the dispersed data with a linearly chirped pump pulse thus imparting a linear frequency sweep to the unconverted wave form. A second dispersive delay line completes the arrangement and forms the temporal analog of a single lens spatial imaging system resulting in a time reversed wave form with a magnification M=−11.7. © 1994 American Institute of Physics.
Show PACS
42.30.-d Imaging and optical processing
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
07.60.-j Optical instruments and equipment

Nonguiding half‐wave semiconductor microcavities displaying the exciton‐photon mode splitting

I. Abram, S. Iung, R. Kuszelewicz, G. Le Roux, C. Licoppe, J. L. Oudar, E. V. K. Rao, J. I. Bloch, R. Planel, and V. Thierry‐Mieg

Appl. Phys. Lett. 65, 2516 (1994); http://dx.doi.org/10.1063/1.112621 (3 pages) | Cited 28 times

Full Text: | Download PDF

Show Abstract
We present a monolithic epitaxially grown λ/2 semiconductor microcavity that contains two InGaAs quantum wells in its AlAs spacer. This particular design displays greatly reduced coupling of the quantum well emission to the in‐plane guided modes. The reflection and luminescence spectra of this structure at 77‐K display an exciton‐photon splitting of 4 meV with as few as two quantum wells, indicating the possibility of a strong coupling of the spontaneous emission of the excitons to the vertical cavity modes. This cavity design should thus be well suited for improving the coupling efficiency of the spontaneous emission to the lasing mode in vertically emitting structures. © 1994 American Institute of Physics.
Show PACS
42.50.-p Quantum optics
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.55.Px Semiconductor lasers; laser diodes
78.66.Fd III-V semiconductors

Phase‐matched second‐harmonic generation in a Ta2O5/KTiOPO4 waveguide

Tohru Doumuki, Hitoshi Tamada, and Masaki Saitoh

Appl. Phys. Lett. 65, 2519 (1994); http://dx.doi.org/10.1063/1.112622 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
Highly efficient phase‐matched second‐harmonic generation (TEω00‐like mode to TE2ω10‐like mode) using waveguide modal dispersions is reported. The waveguide is composed of a KTiOPO4 substrate, a Ta2O5 thin‐film core, and a SiO2 clad in the strip‐loaded configuration. Normalized conversion efficiency of around 1000%/W cm2 and the blue (413 nm) second‐harmonic power of 13 mW were achieved with a 4.1‐mm‐long waveguide. The output beam of the second‐harmonic wave showed a single‐peak power profile, in spite of being first‐order mode in the film thickness directions. © 1994 American Institute of Physics.
Show PACS
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
42.79.Gn Optical waveguides and couplers

Fullerene doped glasses

Fucheng Lin, Sen Mao, Zhicong Meng, Heping Zeng, Jianqing Qiu, Yong Yue, and Ting Guo

Appl. Phys. Lett. 65, 2522 (1994); http://dx.doi.org/10.1063/1.112623 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
Optical glasses doped with a fullerene mixture of C60/C70 were made in our lab. Three peaks, corresponding to C60, C70, and a modified fullerene (possibly its oxide), respectively, were found in the chromatogram of high performance liquid chromatography (HPLC) analysis of the 0.1‐wt % fullerene doped phosphate glass. Depending on the doping procedure and impurity, weak to strong interacting between C60 and its environment was found by the nuclear magnetic resonance study. For both phosphate and fluorophosphate glasses with 0.01‐wt % fullerene mixture doping, the eigen UV absorption edge showed a significant blueshift, indicating that the bonding between the nonbridging oxygen in these glasses was subjected to a strong change due to the fullerene doping. © 1994 American Institute of Physics.
Show PACS
61.46.-w Structure of nanoscale materials
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.40.Ha Other nonmetallic inorganics
76.60.Cq Chemical and Knight shifts

Simple technique for picosecond electrical pulse injection into arbitrary circuits

D. R. Dykaar and S. B. Darack

Appl. Phys. Lett. 65, 2525 (1994); http://dx.doi.org/10.1063/1.112624 (2 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
We demonstrate a new external photoconductive excitation source. Low‐temperature grown GaAs is used as a picosecond electrical pulser. A simple fabrication technique results in probes suitable for wafer scale probing of arbitrary circuits. © 1994 American Institute of Physics.
Show PACS
85.30.De Semiconductor-device characterization, design, and modeling
84.30.-r Electronic circuits

Spin selective x‐ray absorption spectroscopy: Demonstration using high resolution Fe Kβ fluorescence

G. Peng, X. Wang, C. R. Randall, J. A. Moore, and S. P. Cramer

Appl. Phys. Lett. 65, 2527 (1994); http://dx.doi.org/10.1063/1.112625 (3 pages) | Cited 24 times

Full Text: | Download PDF

Show Abstract
In this letter it is shown that high resolution Fe Kβ excitation spectra can be used to separately probe empty spin‐up and spin‐down final states. Spin‐selective x‐ray absorption spectra were obtained by selectively monitoring different regions of the Kβ emission. The fluorescence was excited with monochromatized synchrotron radiation and analyzed using a spherically bent Ge(620) crystal. Spin–polarization was demonstrated by showing that the 1s→3d transition at the Fe K edge is seen with Kβ1,3 detection, but missing in the excitation spectrum using Kβ′ detection. The spin–polarization is also confirmed by ligand field atomic multiplet calculations that reproduce the Kβ spectra. Calculations are presented showing the applicability of spin–polarized Kβ detection to nearly all first transition metal ions. © 1994 American Institute of Physics.
Show PACS
78.70.Dm X-ray absorption spectra
78.70.En X-ray emission spectra and fluorescence
75.25.-j Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source x-ray scattering, etc.)
75.50.Bb Fe and its alloys

Theoretical performance of very long wavelength InAs/InxGa1−xSb superlattice based infrared detectors

C. H. Grein, H. Cruz, M. E. Flatté, and H. Ehrenreich

Appl. Phys. Lett. 65, 2530 (1994); http://dx.doi.org/10.1063/1.112626 (3 pages) | Cited 23 times

Full Text: | Download PDF

Show Abstract
Optimal detectivities of very long wavelength (11–19 μm) photovoltaic infrared detectors based on ideal InAs/InGaSb superlattices are calculated. Accurate K⋅p band structures are used to obtain radiative, electron–electron and hole–hole band‐to‐band Auger, and for the first time shallow acceptor level assisted Auger recombination rates for n‐on‐p photodiodes. The suppression of band‐to‐band Auger by ‘‘band gap engineering’’ is predicted to lead to improved background‐limited operating temperatures just as it does in long‐wave InAs/InGaSb infrared detectors. © 1994 American Institute of Physics.
Show PACS
85.60.Gz Photodetectors (including infrared and CCD detectors)
72.40.+w Photoconduction and photovoltaic effects
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping

Amplitude squeezing of a multiple quantum‐well distributed‐feedback semiconductor laser operating at room temperature—Effect of reduction of spontaneous‐emission noise by Interferometric method

Kazuro Kikuchi, Kazuma Watanabe, and Kazuhiro Katoh

Appl. Phys. Lett. 65, 2533 (1994); http://dx.doi.org/10.1063/1.113033 (3 pages)

Full Text: | Download PDF

Show Abstract
We demonstrate 3.4‐dB amplitude squeezing of a multiple quantum‐well distributed‐feedback semiconductor laser operating at room temperature. The spontaneous‐emission noise is eliminated by using a Michelson interferometer, where the intensity noise due to spontaneous emission is cancelled by the intensity noise converted from the frequency noise. The spectral density of the remaining noise is 3.4 dB below the shot‐noise level, which is limited by the differential quantum efficiency of the laser. © 1994 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Mi Dynamical laser instabilities; noisy laser behavior

Strain compensated InAsP/InP/InGaP multiple quantum well for 1.5 μm wavelength

X. S. Jiang and P. K. L. Yu

Appl. Phys. Lett. 65, 2536 (1994); http://dx.doi.org/10.1063/1.112627 (3 pages) | Cited 17 times

Full Text: | Download PDF

Show Abstract
We report metalorganic vapor phase epitaxy growth of InAs0.66P0.34/InP/In0.74Ga0.26P strain compensated multiple quantum wells (MQWs) at 1.5 μm wavelength. A composite InP/InGaP/InP barrier structure is used to tune the net strain of the MQWs. Compared with InAs0.66P0.34/InP strained MQWs grown under similar conditions, the InAs0.66P0.34/InP/In0.74Ga0.26P strain compensated MQWs show improvement in crystalline and optical quality. © 1994 American Institute of Physics.
Show PACS
81.15.Kk Vapor phase epitaxy; growth from vapor phase
78.66.Fd III-V semiconductors
42.79.Hp Optical processors, correlators, and modulators

Study on photorefractive effect in KTiOPO4 waveguides

L. P. Shi, W. Karthe, and A. Rasch

Appl. Phys. Lett. 65, 2539 (1994); http://dx.doi.org/10.1063/1.112628 (3 pages) | Cited 4 times

Full Text: | Download PDF

Show Abstract
Photorefractive effects (PRE) in KTiOPO4 channel waveguides were studied at the wavelengths 0.633 and 0.83 μm. The 4 μm‐wide waveguides were fabricated by Rb ion exchange on the z‐face of the crystals and along the y axis. At 0.633 μm, crystals from one source showed conventional photorefractive response with a saturation index change Δn of 2×10−5, but samples from a different source were not photorefractive. Neither type of crystals displayed photorefractive behavior in response to 0.83 μm light at guided‐wave power flow of 2.4×107 W/m2. Differences in bicrystal structure are suggested as a possible cause of differing PRE between the two samples. On crystals from the first source, the relaxation time of generating PRE is related to power flow of the irradiating beam. The relaxation time of PRE disappearance after stop irradiation is also related to power flow of the irradiating light. © 1994 American Institute of Physics.
Show PACS
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials

Optically generated liquid crystal gratings

Wayne M. Gibbons and Shao‐Tang Sun

Appl. Phys. Lett. 65, 2542 (1994); http://dx.doi.org/10.1063/1.112629 (3 pages) | Cited 33 times

Full Text: | Download PDF

Show Abstract
Optically controlled planar orientation of liquid crystal molecules with polarized light is used to make phase gratings in liquid crystal media. The electro‐optical properties of liquid crystal linear and chirped gratings are discussed. © 1994 American Institute of Physics.
Show PACS
61.30.Gd Orientational order of liquid crystals; electric and magnetic field effects on order
42.70.Df Liquid crystals

Sol‐gel method for synthesizing visible photoluminescent nanosized Ge‐crystal‐doped silica glasses

Masayuki Nogami and Yoshihiro Abe

Appl. Phys. Lett. 65, 2545 (1994); http://dx.doi.org/10.1063/1.112630 (3 pages) | Cited 45 times

Full Text: | Download PDF

Show Abstract
Ge‐nanocrystal‐embedded SiO2 glasses were prepared by a sol‐gel process. The glasses synthesized through hydrolysis of Si(OC2H5)4 and GeCl4 were heated in the presence of hydrogen at 400–700 °C, in which Ge4+ ions were reduced to precipitate nanosized Ge crystals. Glasses doped with Ge nanocrystals of diameter of ∼5 nm showed a strong room‐temperature photoluminescence with peaks at 2.32, 2.17, and 2.0 eV. Large Ge crystals precipitated by heating at 800 °C showed no photoluminescence. © 1994 American Institute of Physics.
Show PACS
78.55.Hx Other solid inorganic materials
81.15.Lm Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids)
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials
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

Silicon wafer bonding studied by infrared absorption spectroscopy

Diego Feijoó, Y. J. Chabal, and S. B. Christman

Appl. Phys. Lett. 65, 2548 (1994); http://dx.doi.org/10.1063/1.112631 (3 pages) | Cited 20 times

Full Text: | Download PDF

Show Abstract
The interface of hydrophilic and hydrophobic Si wafers joined at room temperature is studied using multiple internal transmission infrared absorption spectroscopy as a function of 30‐min annealing steps in N2 atmosphere up to 1100 °C. For hydrophilic wafers, water molecules are observed up to 300 °C, silanol groups up to 900 °C, and hydrogen up to 1000 °C. The absence of water spectral features above 300 °C implies that, if present, water molecules are mostly oriented in a plane parallel to the interface. For the hydrophobic wafers, the temperature dependence of the Si–H stretch spectra shows that the majority of H does not participate in the bonding, pointing to the role of impurities or defects. © 1994 American Institute of Physics.
Show PACS
68.35.-p Solid surfaces and solid-solid interfaces: structure and energetics
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces

Oxygen depletion of the crystalline (anatase) TiO2 initiated by ionization of the K shell

T. Uustare, J. Aarik, and M. Elango

Appl. Phys. Lett. 65, 2551 (1994); http://dx.doi.org/10.1063/1.112632 (2 pages) | Cited 7 times

Full Text: | Download PDF

Show Abstract
We have shown, using the Auger‐spectroscopy technique, that irradiation of the crystalline (anatase) TiO2 by electrons leads to a considerable oxygen depletion and metallization of the irradiated surface. The threshold energy for this process has been found to be around 530 eV, which coincides with the ionization threshold of the K shell of oxygen. © 1994 American Institute of Physics.
Show PACS
61.80.Fe Electron and positron radiation effects

Cross‐section transmission electron microscope observations of diamond‐turned single‐crystal Si surfaces

Takayuki Shibata, Atsushi Ono, Kenji Kurihara, Eiji Makino, and Masayuki Ikeda

Appl. Phys. Lett. 65, 2553 (1994); http://dx.doi.org/10.1063/1.112633 (3 pages) | Cited 25 times

Full Text: | Download PDF

Show Abstract
Diamond turning was carried out along the [110] direction on the (001) plane of single‐crystal silicons at extremely small depths of cut of 100 and 500 nm. Cross‐section transmission electron microscope observations revealed that turning had converted the layers of the surface into an amorphous structure directly, as well as in continuous chips. The thickness of the layers was about 150 nm in spite of the depth of cut. Under the amorphous layer, another damaged layer with many dislocations was formed, the thickness of which was about 2 and 3 μm at 100‐ and 500‐nm cutting depth, respectively. At 500‐nm cutting depth, microcracks were formed through the accumulation of excessive dislocations. At both depths of cut, however, the dislocations were mostly oriented along the 〈110〉 directions within the {111} planes. It was found that ductile‐regime turning could be achieved by amorphization and deformation based on the {111}〈110〉 slip systems. © 1994 American Institute of Physics.
Show PACS
81.65.-b Surface treatments
68.35.B- Structure of clean surfaces (and surface reconstruction)
62.20.M- Structural failure of materials

Heteroepitaxial growth of ZnO films on diamond (111) plane by magnetron sputtering

Akihiro Hachigo, Hideaki Nakahata, Kenjiro Higaki, Satoshi Fujii, and Shin‐ichi Shikata

Appl. Phys. Lett. 65, 2556 (1994); http://dx.doi.org/10.1063/1.112634 (3 pages) | Cited 31 times

Full Text: | Download PDF

Show Abstract
ZnO thin film has been epitaxially grown on the (111) plane of the diamond substrate by rf magnetron sputtering at substrate temperature as low as 260 °C. The crystallinity was examined by x‐ray diffraction and reflection high‐energy electron diffraction. It was found that the smallest standard deviation angle estimated from the x‐ray rocking curve of the ZnO(0002) peak was 0.27° whereas the mismatch of the lattice parameter between film and substrate is 28.8%. The epitaxial relationship between ZnO film and the diamond is determined as [1120] ZnO//[101] diamond. © 1994 American Institute of Physics.
Show PACS
68.55.-a Thin film structure and morphology
81.15.Cd Deposition by sputtering

Chemical vapor deposition of heteroepitaxial Si1−x−yGexCy films on (100)Si substrates

Z. Atzmon, A. E. Bair, E. J. Jaquez, J. W. Mayer, D. Chandrasekhar, David J. Smith, R. L. Hervig, and McD. Robinson

Appl. Phys. Lett. 65, 2559 (1994); http://dx.doi.org/10.1063/1.112635 (3 pages) | Cited 56 times

Full Text: | Download PDF

Show Abstract
Thin heteroepitaxial films of Si1−x−yGexCy have been grown on (100)Si substrates using atmospheric pressure chemical vapor deposition at 625 °C. The crystallinity, composition, and microstructure of the SiGeC films were characterized using Rutherford backscattering spectrometry, secondary‐ion‐mass spectrometry, and cross‐sectional transmission electron microscopy. The crystallinity of the films was very sensitive to the flow rate of C2H4 which served as the C source. Films with up to 2% C were epitaxial with good crystallinity and very few interfacial defects. Between 800 and 900 sccm of 10% C2H4 in He, the C content increased dramatically from 2% to 10% and the as‐grown films changed from crystalline to amorphous. In order to establish deposition conditions for the crystalline‐amorphous phase transformation, one SiGeC film was deposited as the 10% C2H4 flow was increased linearly from 500 to 1500 sccm during growth. When the C content reached ∼4%, the film developed considerable stacking defects and disorder, and at around 11% C, the film became amorphous. © 1994 American Institute of Physics.
Show PACS
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.-a Thin film structure and morphology

Theoretical study of field emission from diamond

Z.‐H. Huang, P. H. Cutler, N. M. Miskovsky, and T. E. Sullivan

Appl. Phys. Lett. 65, 2562 (1994); http://dx.doi.org/10.1063/1.112636 (3 pages) | Cited 65 times

Full Text: | Download PDF

Show Abstract
The electron field emission from diamond surfaces is investigated theoretically using a model consisting of the projection of the energy band surfaces in the 〈111〉, 〈110〉, and 〈100〉 emission directions. The effect of the negative electron affinity, the band bending, the image interaction, and surface states is examined in detail. It is found that the conventional theory of electron field emission applied to crystalline diamond cannot explain the measured high‐current emission at low fields. We postulate two subbands in the intrinsic band gap, which may be generated by defects or impurities. With reasonable band parameters, the calculated I‐V characteristics agree with experimental data. © 1994 American Institute of Physics.
Show PACS
79.70.+q Field emission, ionization, evaporation, and desorption
73.20.At Surface states, band structure, electron density of states

Pulsed laser deposition and characterization of epitaxial Cu/TiN/Si(100) heterostructures

R. D. Vispute, R. Chowdhury, P. Tiwari, and J. Narayan

Appl. Phys. Lett. 65, 2565 (1994); http://dx.doi.org/10.1063/1.112994 (3 pages) | Cited 21 times

Full Text: | Download PDF

Show Abstract
Three‐dimensional epitaxial Cu/TiN/Si(100) heterostructures have been grown by pulsed laser deposition using a single chamber, in situ processing method. The epitaxial TiN layers on Si(100) were grown at 600 °C and epitaxial Cu layers on TiN/Si(100) in the temperature range 200–600 °C using optimized laser parameters. These structures were characterized using three‐axis x‐ray diffraction (Θ, Φ, Ψ scans) technique and high‐resolution transmission electron microscopy. The results clearly indicate cube‐on‐cube epitaxial alignment along the three axes, i.e., 〈100〉Cu∥〈100〉TiN∥〈100〉Si. The Cu/TiN and TiN/Si interfaces were found to be quite sharp without any indication of interfacial reaction. The growth mechanism of copper on TiN was found to be three dimensional, with the size of island varying from 0.3 to 1.5 μm. We discuss domain matching epitaxy as a mechanism of growth in these large lattice mismatch systems, where three lattice constants of Si(5.43 Å) match with four of TiN(4.24 Å) and seven units of Cu(3.62 Å) match with six of the TiN. The implications of these results in the fabrication of advanced microelectronic devices are discussed. © 1994 American Institute of Physics.
Show PACS
68.55.-a Thin film structure and morphology
81.15.Fg Pulsed laser ablation deposition
85.40.Ls Metallization, contacts, interconnects; device isolation

Low‐temperature conductivity of epitaxial ZnSe in the impurity band regime

M. Vaziri

Appl. Phys. Lett. 65, 2568 (1994); http://dx.doi.org/10.1063/1.112641 (3 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
Low‐temperature conductivity of several samples of ZnSe grown by molecular‐beam epitaxy has been measured. The data indicate that for samples with carrier concentration below or near Nc, metal insulator transition, the conductivity obeys σ=σ0 exp[−(T0/T)s] at low temperatures with s=1/2. This behavior is a characteristic of variable‐range hopping conduction in the presence of a Coulomb gap. © 1994 American Institute of Physics.
Show PACS
73.61.Ga II-VI semiconductors
71.30.+h Metal-insulator transitions and other electronic transitions
71.55.Gs II-VI semiconductors

Enhanced negative ion formation in ultraviolet‐laser irradiated silane: Implications for plasma deposition of amorphous silicon

Lal A. Pinnaduwage, Madhavi Z. Martin, and Loucas G. Christophorou

Appl. Phys. Lett. 65, 2571 (1994); http://dx.doi.org/10.1063/1.112642 (3 pages) | Cited 8 times

Full Text: | Download PDF

Show Abstract
Observation of enhanced electron attachment to ArF‐excimer‐laser irradiated silane is reported. Evidence is presented that highly excited electronic states of silane or its photofragments are responsible for the observed enhanced electron attachment. Since such electronically excited states may be produced in silane plasmas (by direct electron impact or by excitation transfer via metastable states of rare gases that are commonly used in silane discharges), the possible significance of this electron attachment process for negative ion formation in silane plasmas is indicated. © 1994 American Institute of Physics.
Show PACS
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
52.80.Pi High-frequency and RF discharges

Determination of heterojunction band discontinuities in strained AlxIn1−xP/lnP systems

J. Lammasniemi, K. Tappura, and K. Smekalin

Appl. Phys. Lett. 65, 2574 (1994); http://dx.doi.org/10.1063/1.112643 (2 pages)

Full Text: | Download PDF

Show Abstract
Conduction and valence band discontinuities were determined in the strained AlxIn1−xP/InP heterojunction system by absorption measurements from multiquantum well (MQW) and superlattice (SL) structures. It was found that the conduction band offsets were 0.337 and 0.260 eV for systems having Al concentrations of x=0.20 (MQW) and x=0.15 (SL), respectively. The valence band discontinuities were 85 and 49 meV for the heavy‐hole valence band and −29 and −35 meV for the light‐hole valence band, respectively, i.e., the light‐hole valence band of AlxIn1−xP forms a staggered type II heterojunction with InP. © 1994 American Institute of Physics.
Show PACS
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
78.66.Fd III-V semiconductors

Characterization of metal–oxide–semiconductor capacitors, fabricated on (111) β-SiC epilayers grown on (111) TiC

H-S. Chen and J. D. Parsons

Appl. Phys. Lett. 65, 2576 (1994); http://dx.doi.org/10.1063/1.113034 (3 pages) | Cited 1 time

Full Text: | Download PDF

Show Abstract
Metal–oxide–semiconductor (MOS) capacitors, fabricated on two n-type and one p-type (111) β-SiC epilayers, were characterized by C–V measurements. The β-SiC epilayers were grown on (111) bulk TiC substrates, by pyrolysis of disilylethane. Inversion, in the dark, was obtained in MOS capacitor structures on both n-type epilayers; demonstrating the feasibility of inversion mode MOS field effect transistors in β-SiC grown on TiC. The Terman method was used to estimate the interface trap density (Dit) at between 2×1011 cm−2 eV−1 and 1.4×1012 cm−2 eV−1; where Dit increased with carrier concentration. © 1994 American Institute of Physics.
Show PACS
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
85.30.Tv Field effect devices
Page 1 of 2 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close