摘要:

An analysis is presented of the thermodynamics of lattice defects and H or D in rutile. It is shown that the solubility of these imperfections depends strongly on electron Fermi level, which in turn depends on the concentration of the imperfections. A method is presented for using hydrogen solubility to determine conduction band parameters and the energies and densities of electron traps in the crystal. The conditions for obtaining large or small concentrations of H,D or lattice defects are discussed. The use of the method presented depends on an accurate calibration of the oscillator strengths of the H‐D ir absorption in rutile. Such a calibration is presented in the following paper.

ISSN:0021-8979    

DOI:10.1063/1.1662696

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Results of a precise determination of the ir absorption strength of H and D in rutile are presented, which permit determination of H or D concentration to an accuracy of 3%. The integrated absorption per ion was (2.51±0.09)×10−17and (1.33±0.05)×10−17cm forHandD, respectively. The procedure for calculating the H or D concentration in a particular sample from the ir absorption peaks is illustrated. Used in conjunction with the results of the theoretical analysis of the preceding paper, this technique makes possible the accurate determination of the energy and density of all electron trapping levels in TiO2crystals. We also describe results showing that heat treatment in a dry H2atmosphere at ∼800 °C results in the introduction of Ti intersititials but negligible H in the crystal, as predicted by the preceding paper. A technique for measuring diffusion parameters of H and D under conditions of strict chemical equilibrium, thus avoiding the large departures from Fick's law which usually plague such measurements in materials such as TiO2, is also described.

ISSN:0021-8979    

DOI:10.1063/1.1662697

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The atomic mechanism, based on the previously proposed ``inhomogeneous'' shear, leading to the formation of twinning and antiphase boundaries in TiNi with the CsCl‐type structure is described. The twinning mechanism described herein explains the electrical resistivity anomaly due to ``incomplete'' thermal cyclings observed previously in TiNi. This explanation is in keeping, in a qualitative manner, with the ``memory'' effects observed in relation to the electrical resistivity anomaly.

ISSN:0021-8979    

DOI:10.1063/1.1662698

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

In order to study the anomalous ultrasonic attenuation in these compounds, detailed measurements have been performed as a function of temperature, using a variety of frequencies, sound modes, and materials. Their results prove the existence of a selection rule for the interaction mechanism and confirm previous statements of a relaxation process. From symmetry arguments as well as from the observed strong effects of the Ge or Si atoms, respectively, the conclusion was reached that the anomalous attenuation is closely connected to vacancies in the Ge or Si sublattice.

ISSN:0021-8979    

DOI:10.1063/1.1662699

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A model for the diffusion of implanted interstitials during implantation is introduced and shown to be able to account for the tails observed in ion profiles. It is argued that mechanisms of ionization‐enhanced diffusion can explain some of the anomalous diffusion mechanisms observed in semiconductors. Indications for the existence of such mechanisms in the field of ion implantation in semiconductors are discussed.

ISSN:0021-8979    

DOI:10.1063/1.1662700

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A study of the x‐ray powder pattern resulting from a cold‐worked hexagonal close‐packed Au&sngbnd;Cd&sngbnd;In alloy containing 17.5 at.% Cd and 5.0 at.% In has been made. Quantitative analysis of observed anomalous peak broadening, peak shifts, and peak asymmetry in the powder pattern shows evidence for only three of the nine faults, which have earlier been postulated for this structure, namely intrinsic‐ch, intrinsic‐h, and intrinsic‐2hwith respective fault probabilities of &agr;ch=0.045, &agr;h=0.036, and &agr;2h=0.002.

ISSN:0021-8979    

DOI:10.1063/1.1662701

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

In this paper we report on the observation of acoustoelectric effect (transversal and longitudinal) in the layered structure LiNbO3&sngbnd;Si by means of capacity probes, situated on one side of LiNbO3thin plate with surface acoustic waves propagating along the opposite side adjacent to the Si plate. These effects arise due to the penetration into the silicon plate of the electric fields of the surface acoustic wave propagating along the LiNbO3plate. The transversal effect was revealed to be even (i.e., did not change its sign with a reversal of the direction of surface acoustic wave propagation). The longitudinal effect was revealed to be odd. In high‐conductivity Si samples (&sgr;≥10−4&OHgr;−1cm−1) the transversal effect predominated, in low‐conductivity samples the longitudinal effect predominated. Experimental results on the investigation of the transversal acoustoelectric effect as a function of acoustic intensity, conductivity of the silicon specimen, and dc‐drift electric field are given. The comparison of these results with the theory of acoustoelectric effect in layered structures is carried out.

ISSN:0021-8979    

DOI:10.1063/1.1662702

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Two effects of inclusions in or on the surface of infrared‐transmitting materials are to increase the average value of the optical absorption coefficient &bgr; and to cause localized heating that could lead to material failure at high‐power levels. Volume fractions as low as 10−7−10−8of such inclusions can give rise to a value of the optical absorption coefficient &bgr; of 10−4cm−1, a typical value of current interest. For various types of inclusions the frequency dependence of &bgr; ranges from increasing as &ohgr;2, to independent of &ohgr;, to exponentially decreasing with &ohgr;. The temperature dependence ranges from independent ofTto increasing asTpin the high‐temperature limit, wherep≃2–4 typically. Simple expressions for the absorption cross section are derived for various cases of practical interest. The cross sections are used to derive expressions for &bgr; for the four cases of large inclusions of strong and weak absorbers and of small inclusions of dielectric and metallic particles. The material failure resulting from local heating of inclusions is a far greater problem in high‐intensity short‐pulse systems than in low‐intensity long‐pulse or cw systems having the same average intensity. Microsecond pulses with energy densities as low as a few joules per square centimeter can cause material failure.

ISSN:0021-8979    

DOI:10.1063/1.1662703

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Germanium thin films were formed on flexible organic substrates by using a replica method, in order to obtain a sensitive transducer for stress and thermal energy. The average values of measured gauge factor were in the range from 45 to 65. The Seebeck coefficient was up to 560 &mgr;V/deg forp‐type films. With regard to flexibility of the films, stiffness is more than three orders of magnitude smaller than that of a glass substrate. According to dynamic tests, the element attached to a beam could respond to mechanical vibrations up to a frequency of 20 kHz. From the study of the thermal properties using infrared and laser beams, a response time of about 100 msec or less and a responsiveness of about 40&mgr;V/&mgr;W were obtained.

ISSN:0021-8979    

DOI:10.1063/1.1662704

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The result of the measurement of the electron‐ion recombination rate of cesium plasma in a discharge tube is presented. The electron temperature has been extended to 5000 °K and the electron density to 1015cm−3. The comparison of the experimental data with the calculated values (Ref. 7) is considered to be satisfactory

ISSN:0021-8979    

DOI:10.1063/1.1662705

出版商:AIP    

年代:1973

数据来源: AIP