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29 Aug 1988

Volume 53, Issue 9, pp. 725-818

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First GaInAsP‐InP double‐heterostructure laser emitting at 1.27 μm on a silicon substrate

M. Razeghi, M. Defour, F. Omnes, Ph. Maurel, J. Chazelas, and F. Brillouet

Appl. Phys. Lett. 53, 725 (1988); http://dx.doi.org/10.1063/1.99815 (3 pages) | Cited 15 times

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We report the first successful room‐temperature GaInAsP‐InP double‐heterostructure laser emitting at 1.27 μm, grown by low‐pressure metalorganic chemical vapor deposition on a Si substrate. A pulsed threshold current density of 10 kA/cm2 at room temperature with an external quantum efficiency of 10% per facet and an output power of 20 mW (for an oxide‐defined stripe geometry with 12 μm stripe width and 250 μm cavity length) has been measured. The first aging test in pulse operation shows an increase of threshold current of only 7% for a cumulative time of 80 s at room temperature.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
78.47.-p Spectroscopy of solid state dynamics

Impurity‐induced‐disordered phase modulators in AlGaAs/GaAs quantum well and double‐heterostructure waveguides

T. Hausken, T. C. Huang, K. W. Lee, R. J. Simes, N. Dagli, and L. A. Coldren

Appl. Phys. Lett. 53, 728 (1988); http://dx.doi.org/10.1063/1.99816 (3 pages) | Cited 5 times

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Results for two new channel waveguide phase modulators formed by impurity‐induced disordering (IID) with Zn diffusion in AlGaAs/GaAs are presented. One device utilizes side diffusion into ridges of single quantum well material and the other utilizes surface diffusion into double‐heterostructure material. Waveguide loss for both TE and TM polarizations, and effective index steps calculated from observed mode profiles are reported. TE/TM mode conversion was observed without bias under certain conditions. Initial results for phase modulation are in agreement with expectations and appear not to be affected by the IID.
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78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
42.79.Gn Optical waveguides and couplers

Effect of the lifting of Kramer’s degeneracy on excitonic linewidths in quantum well optical modulators

Songcheol Hong, Jasprit Singh, Rajeshwar Sahai, and Chewlan Lastufka

Appl. Phys. Lett. 53, 731 (1988); http://dx.doi.org/10.1063/1.99817 (3 pages) | Cited 4 times

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In symmetric quantum well structures, the hole subband states maintain the spin degeneracy (Kramer’s degeneracy), but in asymmetric quantum wells and in optical modulators in the presence of electric field, the degeneracy is lifted. This results in splitting of excitonic transitions due to splitting in the exciton binding energy. For small splitting this will result in exciton broadening. Comparisons are presented for this broadening in symmetric and asymmetric quantum well structures as a function of electric field. The light hole exciton is found to broaden at an order of magnitude higher rate than the heavy hole exciton. Field‐dependent experimental results for symmetric GaAs/Al0.3Ga0.7As multiquantum well structures are carried out and support the theoretical results.
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78.66.-w Optical properties of specific thin films
78.67.-n Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
78.20.Jq Electro-optical effects

Optical pulse generation with a frequency shifted feedback laser

F. V. Kowalski, S. J. Shattil, and P. D. Hale

Appl. Phys. Lett. 53, 734 (1988); http://dx.doi.org/10.1063/1.99818 (3 pages) | Cited 18 times

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A pulsed ring dye laser is constructed in which the light is shifted in frequency before being fed back into the gain medium. The active medium is R6G dye pumped by a continuous wave argon‐ion laser. An acousto‐optic modulator is used to shift the frequency of the light inside the ‘‘cavity.’’ With this device, we have generated optical pulses with a 9.6 ps FWHM of the autocorrelation trace and measured periods as short as 0.9 ns.
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42.55.Px Semiconductor lasers; laser diodes
42.55.Rz Doped-insulator lasers and other solid state lasers
42.60.Fc Modulation, tuning, and mode locking
42.55.Mv Dye lasers

Optical fiber spatial filtering technique for investigating carrier dynamics

K. Tai, S. L. McCall, and W. T. Tsang

Appl. Phys. Lett. 53, 737 (1988); http://dx.doi.org/10.1063/1.99819 (3 pages) | Cited 1 time

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A new technique using single‐mode fibers as spatial filters for probing carrier dynamics such as diffusion and recombination is introduced. Diffusion coefficients of 5.5 and 5 cm2/s are obtained for optically excited electron‐hole plasmas in a 1.9‐μm‐thick In0.6Ga0.4As0.85P0.15 bulk layer and in an In0.53Ga0.47As/InP quantum well sample with well thickness of 100 Å, respectively.
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78.47.-p Spectroscopy of solid state dynamics
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.30.-j Infrared and Raman spectra
78.40.Fy Semiconductors
71.35.-y Excitons and related phenomena

Chemical vapor deposition of cobalt silicide

G. A. West and K. W. Beeson

Appl. Phys. Lett. 53, 740 (1988); http://dx.doi.org/10.1063/1.100558 (3 pages) | Cited 12 times

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We have deposited polycrystalline cobalt silicide films by chemical vapor deposition using Co2(CO)8 or HCo(CO)4 as the Co source and SiH4 or Si2H6 as the Si source. The Co:Si ratio of the films is controlled by changing the deposition temperature, and CoSi2 stoichiometry is obtained at 300 °C using SiH4 or at 225 °C when Si2H6 is the Si precursor. Carbon or oxygen contamination of the films is <0.5 at. % at deposition temperatures above 200 °C. Resistivities of films deposited near CoSi2 stoichiometry are typically 200 μΩ cm and drop to 40 μΩ cm upon annealing at 900 °C.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Effect of processing on the structure of the Si/SiO2 interface

A. Ourmazd, J. A. Rentschler, and J. Bevk

Appl. Phys. Lett. 53, 743 (1988); http://dx.doi.org/10.1063/1.100559 (3 pages) | Cited 27 times

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Starting from atomically smooth and characterized (100)Si/SiO2 interfaces, we use lattice imaging techniques to investigate the effect of annealing temperature and processing steps on the interfacial structure. Our results show that a c‐SiO2 layer is present under all conditions we have investigated.
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68.35.B- Structure of clean surfaces (and surface reconstruction)
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization

Effect of heat treatment on the properties of gallium‐implanted polycrystalline silicon

H. B. Harrison, Y. Komen, D. X. Cao, and A. P. Pogany

Appl. Phys. Lett. 53, 746 (1988); http://dx.doi.org/10.1063/1.99820 (3 pages) | Cited 3 times

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Polycrystalline silicon films deposited on silicon dioxide were partially amorphized by implantation with 100 keV gallium ions to a dose of 6×1015 cm−2. These films were then subjected to various heat treatments at 580 and 900 °C using conventional furnace or rapid thermal heating techniques. Sudden drops in sheet resistance occurred at lower temperatures with little change upon further heating. However, the high‐temperature annealed specimen shows only an increase in sheet resistance with time. An explanation of these changes is proposed in terms of a liquid phase melting mechanism taking place during the crystallization of the amorphized near‐surface layer. Transmission electron microscopy and Rutherford backscattering observations support this explanation.
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73.25.+i Surface conductivity and carrier phenomena
73.40.Lq Other semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
68.35.Dv Composition, segregation; defects and impurities
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization

Physical origin of the DX center

J. C. Bourgoin and A. Mauger

Appl. Phys. Lett. 53, 749 (1988); http://dx.doi.org/10.1063/1.99821 (3 pages) | Cited 59 times

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When intervalley mixing effects are large enough, they induce a sharp shallow deep instability for a substitutional impurity. We show that this is the case in GaAs for the ground state associated with the L valleys, which becomes located in the forbidden gap under hydrostatic pressure or in GaAlAs alloys, whereas the donor states associated to the Γ and X valleys remain shallow. This result accounts for the behavior of the so‐called DX center.
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71.10.-w Theories and models of many-electron systems
71.55.-i Impurity and defect levels

Electric‐field‐dependent photoconductivity in GaInAs‐InP quantum wells

D. J. Mowbray, M. S. Skolnick, D. Lee, P. A. Claxton, and J. S. Roberts

Appl. Phys. Lett. 53, 752 (1988); http://dx.doi.org/10.1063/1.99822 (3 pages) | Cited 8 times

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We report a study of the effects of an electric field on the excitonic, band‐to‐band photoconductivity spectra of a Ga0.47In0.53As‐InP quantum well structure. In a sample with five wells of widths 10–110 Å we show that for carrier motion normal to the quantum well layers a photoconductivity signal is only observed from those wells which are in a region of nonzero electric field. The spectral line shapes of the transitions in the narrowest two wells show strong variations with field, which we attribute to exciton dissociation at high field, and possibly exciton screening by free carriers trapped in the wells at low fields. The results are compared with photoconductivity spectra of the same structure, but for carrier motion in the plane of the layers. The latter geometry is found to reflect more accurately the sample absorption.
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73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
72.40.+w Photoconduction and photovoltaic effects
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
73.61.Ey III-V semiconductors

Diffusion of ion‐implanted Sn and Sb in heavily doped n‐type silicon

P. E. Andersen, A. Nylandsted Larsen, P. Tidemand‐Petersson, and G. Weyer

Appl. Phys. Lett. 53, 755 (1988); http://dx.doi.org/10.1063/1.99823 (3 pages) | Cited 14 times

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The diffusion of ion‐implanted Sn and Sb in silicon single crystals during rapid thermal annealing at 1000 and 1050 °C has been studied as a function of P donor concentration. For extrinsic/intrinsic carrier concentration ratios (n/ni )≥20, almost identical, extremely large diffusion coefficients are found for both impurities. The diffusion coefficients exhibit approximately an (n/ni )4 dependence. The onset of this dependence is accompanied by the appearance of a new defect‐complex type containing Sb or Sn, respectively.
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61.72.uf Ge and Si
61.72.Bb Theories and models of crystal defects
66.30.J- Diffusion of impurities

Passivation of zinc acceptors in InP by atomic hydrogen coming from arsine during metalorganic vapor phase epitaxy

G. R. Antell, A. T. R. Briggs, B. R. Butler, S. A. Kitching, J. P. Stagg, A. Chew, and D. E. Sykes

Appl. Phys. Lett. 53, 758 (1988); http://dx.doi.org/10.1063/1.99824 (3 pages) | Cited 46 times

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The passivation of zinc acceptors in InP has been observed, originally in zinc‐doped InGaAs/InP heterostructures. Evidence is presented to show that hydrogen, which has been detected by secondary ion mass spectrometry, is responsible for the phenomenon and that the source of atomic hydrogen is the arsine used in the epitaxial process. The hydrogen is bound within the epitaxial layers during the cooling down stage after growth is complete.
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71.55.Eq III-V semiconductors
73.61.Ey III-V semiconductors
85.40.Ls Metallization, contacts, interconnects; device isolation

Donor gettering in GaAs by rare‐earth elements

J. Raczyńska, K. Fronc, J. M. Langer, A. Lemańska, and A. Stapor

Appl. Phys. Lett. 53, 761 (1988); http://dx.doi.org/10.1063/1.99825 (3 pages) | Cited 17 times

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Optical and electrical measurements of GaAs layers grown by liquid phase epitaxy with different amounts of Yb metal (0–1000 ppm) added to the Ga solution are reported. The presence of Yb during growth causes strong suppression of all donor‐related optical transitions due to the effective removal of donors, as judged from Hall effect data. We have not found any appreciable increase of the background acceptor concentration during conductivity conversion from n‐type to p‐type, and thus conclude that dominant donor gettering occurs already in the Ga solution. No Yb3+ (4f 13)‐related emission was detected in the as‐grown GaAs layers.
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81.15.Lm Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids)
72.20.Fr Low-field transport and mobility; piezoresistance
78.55.Cr III-V semiconductors

Influence of striations in GaAs on the activated profiles of implanted silicon

H. Schink and R. D. Schnell

Appl. Phys. Lett. 53, 764 (1988); http://dx.doi.org/10.1063/1.99826 (3 pages)

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Liquid‐encapsulated Czochralski‐grown GaAs is known to show radial striations. In GaAs:In they can be seen by x‐ray topography via fluctuations of the In concentration which cause variations in the lattice constant. Using a high spatial resolution capacitance‐voltage technique we investigated In‐doped as well as undoped GaAs. It is demonstrated that both materials exhibit striations in the activation behavior of implanted silicon and hence in the threshold voltage of ion‐implanted metal‐semiconductor field‐effect transistors. In the cases investigated here the threshold voltage varied by up to ±12 mV from peak to peak. To our knowledge this is the first time that the effect of striations on the activation behavior of implanted Si is demonstrated in both kinds of substrate material.
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61.72.U- Doping and impurity implantation
61.72.sd Impurity concentration
61.72.sh Impurity distribution
61.72.sm Impurity gradients
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
81.10.Fq Growth from melts; zone melting and refining

Low‐temperature (250 °C) selective epitaxy of GaAs films and p‐n junction by laser‐assisted metalorganic chemical vapor deposition

N. H. Karam, H. Liu, I. Yoshida, and S. M. Bedair

Appl. Phys. Lett. 53, 767 (1988); http://dx.doi.org/10.1063/1.99827 (3 pages) | Cited 9 times

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Low‐temperature selective epitaxial growth of device quality GaAs has been achieved by laser‐assisted chemical vapor deposition (LCVD). GaAs substrates thermally biased to temperatures in the range 250–500 °C were irradiated by an Ar ion laser to induce localized deposition of GaAs. Carefully selected growth conditions resulted in growth rates as low as a monolayer per second at 250 °C. This is the lowest substrate temperature for epitaxial GaAs with optical and structural quality comparable to those achieved in conventionally metalorganic chemical vapor deposition grown GaAs. Also reported is the first p‐n junction by LCVD technique using zinc as the p‐type dopant. This new low‐temperature selective deposition process can lead to maskless fabrication of multicomponent devices on the same wafer.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
73.61.Ey III-V semiconductors
72.80.Ey III-V and II-VI semiconductors
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Effect of post‐oxidation anneal temperature on radiation‐induced charge trapping in metal‐oxide‐semiconductor devices

J. R. Schwank and D. M. Fleetwood

Appl. Phys. Lett. 53, 770 (1988); http://dx.doi.org/10.1063/1.99828 (3 pages) | Cited 26 times

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Polycrystalline silicon‐gate metal‐oxide‐semiconductor (MOS) capacitors have been fabricated with high‐temperature anneals from 800 to 950 °C after gate oxidation and polycrystalline silicon deposition. Temperatures from 800 to 875 °C are found to have very little effect on the radiation response of these devices. However, a rapid increase in radiation‐induced oxide‐trapped charge, ΔVot, is observed for anneal temperatures above 875 °C. This increase in ΔVot coincides with an experimentally observed change in the polycrystalline silicon grain structure. The anneal temperature was found to have a much smaller effect on radiation‐induced interface‐trap charge. The correlation of these results to other properties, e.g., stress, is discussed.
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73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
61.80.Cb X-ray effects
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization
84.32.Tt Capacitors

Low‐temperature heteroepitaxial growth of InSb on CdTe by metalorganic chemical vapor deposition

J. C. Chen, P. Bush, W. K. Chen, and Pao‐Lo Liu

Appl. Phys. Lett. 53, 773 (1988); http://dx.doi.org/10.1063/1.99829 (3 pages) | Cited 6 times

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We report the low‐temperature metalorganic chemical vapor deposition of InSb on (001)CdTe. This low‐temperature process was carried out by a precracking technique. Epitaxial growth with a substrate temperature as low as 185 °C can be obtained using a simple two‐stage heater. The deposited films were examined by double‐crystal x‐ray diffraction, scanning electron microscope, and energy dispersive analysis of x ray. The films grown at 240 °C are stoichiometric, single crystal, and of specular surface morphology.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.15.Kk Vapor phase epitaxy; growth from vapor phase
68.35.B- Structure of clean surfaces (and surface reconstruction)

Temperature dependence of Hall effect in arsenic‐doped silicon at intermediate dopant density

Alice L. Lin

Appl. Phys. Lett. 53, 776 (1988); http://dx.doi.org/10.1063/1.99830 (3 pages) | Cited 5 times

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Temperature dependence of Hall effect in arsenic‐doped silicon at intermediate dopant concentrations from 1.8×1017 to 2.5×1018 cm−3 and low compensation is investigated. Activation energies of As in Si from experimental results are compared to calculated values available in literature for arsenic concentrations up to 1×1018 cm−3 . A critical dopant density (∼5×1017 cm−3 ) is found, below which calculated results agree well with experimental results and above which the calculated values exceed experimentally determined energies. The discrepancy increases with increasing dopant density. The phenomenon is explained by the delocalization of D− states and the broadening of the D− band, which are also evident from the experimental Hall mobility results.
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72.20.My Galvanomagnetic and other magnetotransport effects
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping

Novel configuration of self‐electro‐optic effect device based on asymmetric quantum wells

J. Khurgin

Appl. Phys. Lett. 53, 779 (1988); http://dx.doi.org/10.1063/1.99831 (3 pages) | Cited 20 times

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A new configuration of self‐electro‐optic effect device (SEED), based on combination of two asymmetric quantum wells, is proposed. The new device, the so‐called scissors SEED, does not require the existence of sharp exciton transitions and therefore can in principle operate in a wider range of wavelengths and temperatures than conventional SEED.
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85.60.-q Optoelectronic devices
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems

Strain‐induced lateral confinement of excitons in GaAs‐AlGaAs quantum well microstructures

K. Kash, J. M. Worlock, M. D. Sturge, P. Grabbe, J. P. Harbison, A. Scherer, and P. S. D. Lin

Appl. Phys. Lett. 53, 782 (1988); http://dx.doi.org/10.1063/1.99832 (3 pages) | Cited 55 times

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We report evidence for lateral confinement of excitons within a continuous two‐dimensional GaAs‐AlGaAs quantum well. The confinement to ‘‘wires’’ within the well was produced by partially etching a pattern through the upper AlGaAs barrier. We propose a new mechanism, that of patterned strain, for lateral quantum confinement of carriers in semiconductor microstructures, to explain our results.
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78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
78.20.hb Piezo-optical, elasto-optical, acousto-optical, and photoelastic effects

Theoretical investigation of hole transport in strained III‐V semiconductors: Application to GaAs

J. M. Hinckley and J. Singh

Appl. Phys. Lett. 53, 785 (1988); http://dx.doi.org/10.1063/1.99833 (3 pages) | Cited 11 times

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A Monte Carlo method has been developed and applied to study the anisotropic transport of holes in unstrained and strained bulk III‐V compound semiconductors. In this letter, we present the results for the prototypical GaAs, T=300 K material system. We find that the hole mobility can be significantly increased by the presence of biaxial compressive strain in the system. This arises from strain‐induced modifications in the densities of states and the overlap functions and from a separation of the heavy and light hole bands at k=0 which decreases the heavy to light hole interband scattering. For a 1.5% biaxial compressive strain, the hole mobilities are increased by up to a factor of 2 over the unstrained values. This improvement is sustained up to the highest field in our simulations which was 20 kV/cm.
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72.10.Bg General formulation of transport theory
72.20.Dp General theory, scattering mechanisms
72.80.Ey III-V and II-VI semiconductors
85.30.De Semiconductor-device characterization, design, and modeling

Electrical transport properties in epitaxial codeposited CoSi2 layers on 〈111〉 Si

J. Y. Duboz, P. A. Badoz, E. Rosencher, J. Henz, M. Ospelt, H. von Känel, and A. Briggs

Appl. Phys. Lett. 53, 788 (1988); http://dx.doi.org/10.1063/1.100560 (3 pages) | Cited 34 times

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Electrical measurements (resistivity, Hall effect, and superconducting critical temperature) are performed in epitaxial CoSi2 layers obtained by room‐temperature codeposition of Co and Si on 〈111〉 Si subsequently annealed between 250 and 650 °C. On the one hand, the CoSi2 layers annealed at low temperature (250–350 °C) exhibit poorer electrical characteristics than the films realized by solid phase epitaxy at 650 °C, because of both a lack of carriers and a degraded mobility. A possible origin of this fact could be the presence of unreacted Co atoms in the metal layer. On the other hand, the films annealed ex situ at 700 °C show excellent electrical characteristics, together with mirror‐like surfaces and extremely smooth Si/CoSi2 interfaces, for silicide thicknesses ranging from 35 up to 500 Å. Furthermore, by comparing the films obtained by the solid phase epitaxy and the codeposition techniques, we show that the long‐range roughness (few hundreds of angstroms) has no major influence on the steep increase of resistivity with decreasing film thicknes observed in ultrathin CoSi2 layers.
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72.15.Eb Electrical and thermal conduction in crystalline metals and alloys
73.61.Ng Insulators
73.61.Cw Elemental semiconductors
73.61.Jc Amorphous semiconductors; glasses
73.61.Le Other inorganic semiconductors

Realization of a quasi‐three‐dimensional modulation‐doped semiconductor structure

M. Shayegan, T. Sajoto, M. Santos, and C. Silvestre

Appl. Phys. Lett. 53, 791 (1988); http://dx.doi.org/10.1063/1.99834 (3 pages) | Cited 85 times

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We report the realization of a modulation‐doped quasi‐three‐dimensional electron system. The structure consists of a 2000‐Å‐wide undoped AlxGa1−xAs well bounded by undoped (spacer) and doped layers of AlyGa1−yAs (y>x) on both sides. The alloy composition in the well (x) is varied quadratically so that the combined potentials due to the AlxGa1−xAs and the electric charge in the well produce a square potential well with a nearly uniform carrier density. Magnetotransport data reveal that the system contains ≂2.5×1011 cm−2 electrons, which occupy four electric subbands and have a low‐temperature mobility in excess of 1×105 cm2/V s indicating the high quality of the structure.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
73.61.Ey III-V semiconductors

Deep trench structures in silicon for sensitivity enhancement of Si/SiO2 interface studies

J. H. Stathis, E. Bassous, and B. A. Scott

Appl. Phys. Lett. 53, 794 (1988); http://dx.doi.org/10.1063/1.100561 (2 pages)

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The measurement of defects at the silicon‐insulator interface by most spectroscopic techniques is difficult because of their low concentration. A novel structure has been fabricated by etching a dense array of deep trenches through a silicon wafer. All the sidewalls in this structure are {111} surfaces, and the surface area is greatly enhanced compared to that of a polished wafer of equivalent size. We have grown an oxide on this structure and have achieved better than an order of magnitude increase in the sensitivity of electron paramagnetic resonance measurements of Pb defects at the SiO2‐Si(111) interface.
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61.05.Qr Magnetic resonance techniques; Mössbauer spectroscopy (for structure determination only)
07.57.Pt Submillimeter wave, microwave and radiowave spectrometers; magnetic resonance spectrometers, auxiliary equipment, and techniques
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
76.30.Mi Color centers and other defects

Microwave detection and mixing in Y‐Ba‐Cu‐O thin films at liquid‐nitrogen temperatures

Janusz Konopka, Roman Sobolewski, Anna Konopka, and Stanisław J. Lewandowski

Appl. Phys. Lett. 53, 796 (1988); http://dx.doi.org/10.1063/1.100562 (3 pages) | Cited 13 times

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Microwave properties of an Y‐Ba‐Cu‐O microstrip detector have been studied at 24 GHz frequency band at the liquid‐nitrogen temperature. The amplitude of the video detection signal was found to be proportional to the incident microwave power. Direct mixing action was also demonstrated, setting the upper limit for the film response time as short as 40 ps. Occurrence of microwave mixing in the absence of dc current bias was observed, suggesting the presence of the inverse Josephson effect. Physical properties of the detector response were very similar to the enhanced mode of detection, characteristic for granular superconducting films.
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74.78.-w Superconducting films and low-dimensional structures
74.70.-b Superconducting materials other than cuprates
85.25.Qc Superconducting surface acoustic wave devices and other superconducting devices
78.70.Gq Microwave and radio-frequency interactions
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