摘要:

Anomalous Hall effects, i.e., peaks in the temperature dependence of the Hall coefficient and Hall mobility, have been observed in liquid‐phase‐epitaxy (LPE) Hg0.8Cd0.2Te films. After establishing that surface effects are not the cause of the anomalies and that our LPE films are indeedntype, we propose an inhomogeneity model with a network of extendedp‐type inclusions in ann‐type matrix. Good fits to the experimental data have been obtained by computer simulation based on this model.

ISSN:0021-8979    

DOI:10.1063/1.335819

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Temperature‐dependent current‐voltage (I‐V) and capacitance‐voltage (C‐V) measurements reveal that a low but nonzero barrier is present at the interface of Al deposited on ultrahigh‐vacuum‐cleavedn‐InP (110), and that the true barrier height lies between 0.21–0.26 eV. An analysis which allows for the presence of trapped charge near the interface provides the most accurate and consistent determination of the effective barrier. The effective barrier is strongly and reversibly temperature dependent, corresponding to movement of the Fermi level with temperature. The trapped interfacial charge resides in acceptorlike electron traps 0.10 eV below the conduction‐band edge. The traps are distributed 100–200 A˚ into the space‐charge region. These results are discussed in terms of models of defect electrical activity at metal‐semiconductor interfaces, and are related to results of annealing studies.

ISSN:0021-8979    

DOI:10.1063/1.335820

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Alloy films of Mo and simple metal elements M(M=Ag, Mg, Sn, Sb, Bi, and Ge) have been produced by coevaporation method on substrates kept at about 80 K and their structure and electrical resistivity have been measured. The Mo‐Sn and Mo‐Sb films are found to be amorphous superconductors with a superconducting transition temperature of about 6 K at most. The Mo‐Bi films are also superconductors but crystalline; they show the same x‐ray diffraction pattern as that of hcp Bi. The upper critical fieldHc2has been measured for Mo‐Sn and Mo‐Sb films. TheHc2increases linearly with decreasing temperature down to 1.5 K. The value ofHc2extrapolated to 0 K is found to exceed the paramagnetic limit.

ISSN:0021-8979    

DOI:10.1063/1.335821

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The dispersion of higher‐order localized elastic modes of gold layers on glass has been measured by Brillouin scattering. For layer thicknessesh≥100 A˚ the dispersion of the sound velocities is well described by elastic continuum theory, whereas forh<100 A˚ deviations occur due to island formation. The results yield a reliable, nondestructive method to determine either elastic constants and mass density or the thickness of thin supported metal layers.

ISSN:0021-8979    

DOI:10.1063/1.335822

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

A series of platinum‐oxygen alloys were grown by sputter deposition using a platinum target and rf‐excited, oxygen‐bearing discharges. The films were deposited on water‐cooled single‐crystal silicon and glass substrates. Optical behavior in the near‐ultraviolet–visible–near‐infrared region was studied by spectrophotometry. Changes in reflection and transmission were correlated with changes in film chemistry and structure. The absorption coefficient and two‐infrared optical transitions across the band gap were determined for a semiconducting Pt‐oxide phase, identified by x‐ray photoelectron spectroscopy as &agr;‐PtO2. These transitions occur at 1.30 eV (0.95 &mgr;m) and 1.47 eV (0.84 &mgr;m).

ISSN:0021-8979    

DOI:10.1063/1.335823

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The effects of thermochemical reduction in nickel‐doped MgO crystals have been investigated by cathodoluminescence and transmission electron microscopy. Two cathodoluminescence bands at 410 nm (3.0 eV) and 490 nm (2.5 eV) have been observed. The former band appears only in specimens after reducing treatments and is attributed to anion vacancies. The latter is associated with Ni2+transitions1T2g→3A2g. The results are analyzed on the basis of the emission from F‐type centers and Ni2+ions. Transmission electron microscopy confirms the presence of precipitate groups as well as pyramids in specimens after thermochemical reduction.

ISSN:0021-8979    

DOI:10.1063/1.335824

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Magneto‐optical spectroscopy and hysteresis loops have been used to studynondestructivelythe effect of 100‐keV Ne+implantation in epitaxial Y3Fe5O12thin films. The results show the formation of a damaged layer of 0.13 &mgr;m thickness. The stress‐induced anisotropy field reaches maximum values of 3.2×104A/m for an ion dose of 2×1014cm−2. A decrease in both magnetization and magnetostriction down to 3.6×104A/m and −1.2×10−6, respectively, was observed for an ion dose of 4×1014cm−2. The magneto‐optical spectra were found to reduce in magnitude but not in shape with increasing implantation dose.

ISSN:0021-8979    

DOI:10.1063/1.335825

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

B–C–N–H thin films were deposited by plasma chemical‐vapor deposition with an external capacitively coupled reactor at an rf frequency of 13.56 MHz. The films were formed from a gas mixture of B2H6(5.25 vol % in N2), methane, and argon or nitrogen as carrier gases. The deposition was carried out at room temperature and without heating the substrate. The films were transparent in the range of 10 000–2000‐A˚ wavelengths. The Knoop microhardnesses were 1825–3324 kg/mm2and the refractive index was 1.3–1.6. An extensive discussion of the effect of the deposition conditions on both microhardness and film composition is given. In addition, the interrelation between the microhardness and composition is illustrated.

ISSN:0021-8979    

DOI:10.1063/1.335826

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The new Pt silicide formation method using the reaction between Pt film and SiH4has been proposed. It has been found that Pt silicide is formed by the reaction with SiH4at a low temperature range of 250–400 °C. Parabolic relationships of silicide growth using the reaction with SiH4as well as the growth using the reaction between Pt and substrate Si are confirmed. Pt silicide formation with SiH4is less influenced by oxygen contamination than the formation by the reaction between Pt and substrate Si.

ISSN:0021-8979    

DOI:10.1063/1.335827

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Observation is made on the rf‐plasma oxidation process of a Pb alloy across the priorly existing thermal oxide. This is carried out through the analyses of the ultrathin (several nanometers) oxide formed by the oxygen isotope with the secondary ion mass spectroscopy. It shows that a good deal of oxygen arriving at the oxygen–oxide interface remains and forms oxides in the outer portion of the oxide. Hence the interstitial or substitutional transport of metal ions or substitutional transport of oxygen ions through the thermal oxide is more important than the oxygen‐ion interstitial transport that has been considered responsible for rf‐plasma oxidation. Furthermore, it is elucidated that the thermal oxide remains even after rf‐plasma oxidation except for a probable slight decrease due to sputtering in the early stages of rf‐plasma oxidation. This explains the importance of the thermal oxide in determining the properties of the oxide as a whole.

ISSN:0021-8979    

DOI:10.1063/1.335828

出版商:AIP    

年代:1985

数据来源: AIP