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Existence of an isotope shift for the sulfur deep level in silicon

D. R. Myers and W. E. Phillips

Appl. Phys. Lett. 32, 756 (1978); http://dx.doi.org/10.1063/1.89919 (3 pages) | Cited 7 times

Online Publication Date: 8 August 2008

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The deep energy level of the isotope ³⁴S in the upper half of the energy gap of silicon is examined by isothermal transient capacitance measurements on ion‐implantation‐predeposited diode structures. The resulting energy level at E_c−0.512 eV is found to be 0.014 eV closer to the conduction band edge than the corresponding deep level for the isotope ³²S in similarly prepared samples. The existence of an isotope shift for the deep sulfur level is interpreted as implying vibronic coupling between the electronic states of the sulfur center and the silicon lattice.

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78.40.Fy	Semiconductors
63.20.kp	Phonon-defect interactions
61.72.U-	Doping and impurity implantation

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Liquid‐phase epitaxial growth of lattice‐matched InGaAsP on (100)‐InP for the 1.15–1.31‐μm spectral region

M. Feng, T. H. Windhorn, M. M. Tashima, and G. E. Stillman

Appl. Phys. Lett. 32, 758 (1978); http://dx.doi.org/10.1063/1.89920 (4 pages) | Cited 17 times

Online Publication Date: 8 August 2008

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The distribution coefficients for the growth of lattice‐matched InGaAsP on (100) ‐InP substrates in the 1.15–1.31‐μm spectral range have been determined. These results have been used in the growth of heterojunction photodiodes with quantum efficiencies ⩾48% at 1.27 μm.

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68.55.-a	Thin film structure and morphology
85.60.Dw	Photodiodes; phototransistors; photoresistors

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Interfacial recombination velocity in GaAlAs/GaAs heterostructures

R. J. Nelson and R. G. Sobers

Appl. Phys. Lett. 32, 761 (1978); http://dx.doi.org/10.1063/1.89921 (3 pages) | Cited 55 times

Online Publication Date: 8 August 2008

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Photoluminescence time‐decay measurements on Ga_0.5Al_0.5As/GaAs double heterostructures were made over a wide range of GaAs active layer thickness and doping levels at room temperature. Observed decay times τ in variously doped GaAs samples range from 10 to 450 nsec. Effects of self‐absorption of luminescence and doping level are demonstrated for GaAs layer thickness d≳1 μm. For d<1 μm, the observed decay times are nearly independent of doping level and vary almost linearly with d. The data are interpreted in terms of a small interfacial recombination velocity (S_i=450±100 cm/sec) at the Ga_0.5Al_0.5As/GaAs interface. The value of S_i determined here is an average over the doping levels examined.

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73.40.Lq	Other semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
68.35.-p	Solid surfaces and solid-solid interfaces: structure and energetics
78.40.Fy	Semiconductors

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Pressure dependence of the deep level associated with oxygen in n‐GaAs

A. Zylbersztejn, R. H. Wallis, and J. M. Besson

Appl. Phys. Lett. 32, 764 (1978); http://dx.doi.org/10.1063/1.89887 (3 pages) | Cited 28 times

Online Publication Date: 8 August 2008

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Transient capacitance measurements have been performed on Schottky barriers on n‐GaAs containing the deep electron trap associated with oxygen, as a function of hydrostatic pressure. It is found that the oxygen level separates from the conduction band at a linear rate of 3.8±0.3 meV/kbar. From a comparison with published optical data we conclude that most of this variation comes from a pressure‐dependent Frank‐Condon shift and that the unoccupied level separates very little from the valence band.

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78.40.Fy	Semiconductors
73.30.+y	Surface double layers, Schottky barriers, and work functions
71.70.Ej	Spin-orbit coupling, Zeeman and Stark splitting, Jahn-Teller effect

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Measurement of forward and reverse signal transfer coefficients for an rf‐biased SQUID

R. P. Giffard and J. N. Hollenhorst

Appl. Phys. Lett. 32, 767 (1978); http://dx.doi.org/10.1063/1.89888 (3 pages) | Cited 10 times

Online Publication Date: 8 August 2008

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Comprehensive measurements of the parameters characterizing an rf‐biased SQUID as a linear twoport are described. The behavior of the device corresponds in detail to the predictions of a recently published model of SQUID operation and is unexpectedly similar to that of a conventional reactive parametric amplifier. The measurements have been used to make the first reliable predictions of the noise temperature and optimum source impedance of an rf‐biased SQUID.

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74.50.+r	Tunneling phenomena; Josephson effects
07.55.-w	Magnetic instruments and components
84.30.Le	Amplifiers
85.25.-j	Superconducting devices

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Josephson‐effect absolute noise thermometer: Resolution of unmodeled errors

R. J. Soulen and R. P. Giffard

Appl. Phys. Lett. 32, 770 (1978); http://dx.doi.org/10.1063/1.89889 (3 pages) | Cited 14 times

Online Publication Date: 8 August 2008

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An absolute cryogenic temperature scale is being defined at the National Bureau of Standards using the linewidth of radiation emitted by a resistively shunted Josephson junction. We report careful measurements of the impedance of this noise thermometer and show that its behavior is in excellent agreement with the predictions of the resistively shunted junction model assuming a sinusoidal current‐phase relationship. The implications for absolute noise thermometry are discussed.

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74.50.+r	Tunneling phenomena; Josephson effects
05.40.-a	Fluctuation phenomena, random processes, noise, and Brownian motion
07.20.Dt	Thermometers

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Cold working Nb₃Al in the bcc structure and then converting to the A‐15 structure

G. W. Webb

Appl. Phys. Lett. 32, 773 (1978); http://dx.doi.org/10.1063/1.89890 (3 pages) | Cited 15 times

Online Publication Date: 8 August 2008

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It is possible to quench gram quantities of stoichiometric Nb₃Al in the ductile body‐centered cubic structure which can be cold worked. Later annealing converts this material to the brittle superconducting A‐15 structure.

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74.70.-b	Superconducting materials other than cuprates
74.25.-q	Properties of superconductors
81.30.Hd	Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder
81.40.Ef	Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization

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Low‐noise Josephson mixers at 115 GHz using recyclable point contacts

Y. Taur and A. R. Kerr

Appl. Phys. Lett. 32, 775 (1978); http://dx.doi.org/10.1063/1.89891 (3 pages) | Cited 9 times

Online Publication Date: 8 August 2008

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Thermally recyclable Nb point‐contact Josephson junctions are investigated as low‐noise mixers with an external local oscillator at 115 GHz. The best single sideband mixer noise temperature achieved is 140 (±20) K with a (SSB) conversion loss of 2.4 (±0.5) dB. Such rugged junctions are suitable for use in practical receivers and should give unprecedented sensitivity at the shorter millimeter wavelengths.

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74.50.+r	Tunneling phenomena; Josephson effects
07.57.Kp	Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
85.25.-j	Superconducting devices

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Quantification of atom‐probe FIM data and an application to the investigation of surface segregation of alloys

T. T. Tsong, Yee S. Ng, and S. V. Krishnaswamy

Appl. Phys. Lett. 32, 778 (1978); http://dx.doi.org/10.1063/1.89892 (3 pages) | Cited 22 times

Online Publication Date: 8 August 2008

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It is shown that the atom‐probe field‐ion‐microscope data does not give directly the true composition of a sample. A method is devised for converting the data to the true composition. We also report here the first ToF atom‐probe study of surface segregation of Pt–5% Ru and Pt–8% W alloys. Using the new analysis the true composition depth profiles of the alloys are obtained with a single atomic layer resolution.

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68.70.+w	Whiskers and dendrites (growth, structure, and nonelectronic properties)
79.70.+q	Field emission, ionization, evaporation, and desorption
68.35.Md	Surface thermodynamics, surface energies

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Free‐electron momentum modulation by means of limited interaction length with light

R. H. Pantell and M. A. Piestrup

Appl. Phys. Lett. 32, 781 (1978); http://dx.doi.org/10.1063/1.89893 (3 pages) | Cited 8 times

Online Publication Date: 8 August 2008

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An analysis is performed to determine the energy exchange between light and free electrons when the interaction length is limited. Restricting the length introduces a momentum uncertainty which can be sufficient to allow energy transfer in vacuum if the particles are relativistic and the angle between the direction of particle motion and light wave vector is small.

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41.60.-m	Radiation by moving charges
84.47.+w	Vacuum tubes
41.75.Fr	Electron and positron beams
42.60.Jf	Beam characteristics: profile, intensity, and power; spatial pattern formation

BROWSE VOLUMES

1 Jun 1978

Volume 32, Issue 11, pp. 695-783

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