摘要:

A method of obtaining unsupported single‐crystal films of Ge has been developed which involves the sublimation of a NaCl substrate from the Ge film after vacuum deposition. This allows compatibility of the film and NaCl substrate previously thought impossible due to the large difference in their coefficients of thermal expansion.Evaluation of this endeavor has been made with microscopic, x‐ray diffraction, and electron diffraction examinations. This evaluation has disclosed that the films are (100) oriented monocrystalline films which contain, in varying amounts, surface contaminants consisting of NaCl, BaCl2, Ta2O5, TaC, and amorphous C.

ISSN:0021-8979    

DOI:10.1063/1.1713146

出版商:AIP    

年代:1964

数据来源: AIP

摘要:

Vapor phase transport of Si over a short distance by means of the iodide and subsequent epitaxial growth on a Si substrate is described. Both the source and the substrate were biconcavely shaped pellets piled up in a silica ampule. The furnace was vertical and the temperature ranged from 1100°–1200°C, giving rise to a slight temperature gradient over the length of the ampule.

ISSN:0021-8979    

DOI:10.1063/1.1713147

出版商:AIP    

年代:1964

数据来源: AIP

摘要:

Linear imperfections, oriented in or near the ⟨110⟩ directions, accompany ⟨xxy⟩ and ⟨110⟩ electrical breakdown paths formed in LiF single crystals at room temperature. They may be screw dislocation pairs produced by the action of the electrical field on dislocation loops that were generated in the vicinity of the breakdown path.

ISSN:0021-8979    

DOI:10.1063/1.1713148

出版商:AIP    

年代:1964

数据来源: AIP

摘要:

A diffusion technique is described that does not involve the usual long‐time approximation for a thin specimen. Activity measurements are programmed on a digital computer to generate a large number ofDvalues from the analysis of the data. TheseDvalues are then treated statistically, the resulting distribution curve yielding information on the experiment itself. The technique is fairly insensitive to errors in determining the scattering characteristics of the system or in taking the data.A version of this technique applied to Pb at 300°±2°C yielded average and rms values forD, the self‐diffusion coefficient, of 1.78±0.15×10−10cm2/sec and 1.92±0.16×10−10cm2/sec, respectively, from 40Dvalues generated from the data. The results compare favorably with the published data on self‐diffusion in Pb at 301°C by von Hevesy, 1.85×10−10cm2/sec. The data were also treated according to a long‐time approximation method of Zhukhovitsky, yielding 1.70×10−10cm2/sec.

ISSN:0021-8979    

DOI:10.1063/1.1713149

出版商:AIP    

年代:1964

数据来源: AIP

摘要:

The self‐diffusion of antimony has been measured in single crystals with the tracer124Sb. The least‐squares fit to the data gives in the direction of the trigonal axisQ‖=47.1±1.2 kcal/mole and ln(D0in cm2/sec)=3.1±0.7, and in the plane perpendicular to the trigonal axisQ‖=44.4±4.9 kcal/mole and ln(D0in cm2/sec)=2.81±2.8. The standard sectioning technique was used except that the very friable nature of the semimetal complicated the procedure at practically every step of the operation. The greatest source for the inaccuracy arose from the ``tails'' on the deep penetration side, noticable forD‖and strongly prominent forD‖. Correlation considerations in the Sb lattice are considered in detail in the Appendix.

ISSN:0021-8979    

DOI:10.1063/1.1713150

出版商:AIP    

年代:1964

数据来源: AIP

摘要:

The high‐pressure phase of cadmium sulfide has been recovered to room pressure and room temperature. The recovered phase had the rocksalt structure witha0=5.464±0.012 Å. The pressure dependence of the electrical resistance was found to vary significantly among the various cadmium sulfide phases.

ISSN:0021-8979    

DOI:10.1063/1.1713151

出版商:AIP    

年代:1964

数据来源: AIP

摘要:

This paper discusses some applications of the epsilon algorithm (EA), a sequential procedure for calculating Pade´ approximants. The EA may be used to: (1) accelerate the convergence of slowly converging series and iterations; (2) obtain useful results from divergent series and iterations; (3) obtain the limits of iterated vector and matrix sequences; (4) aid in the solution of differential and integral equations; (5) carry out numerical integration in a new way; (6) extrapolate; (7) fit a curve to a polynomial or to a constant plus sum of exponentials.As an illustration of curve fitting and extrapolation, we present results obtained with exact polynomial data plus random noise combined additively or proportionately. For such nonstationary data, the results are comparable, and in some cases superior, to least squares in yielding good estimates of the exact polynomial coefficients. One important advantage of the EA is that it builds up polynomials whose lower‐order coefficients are independent of higher‐order ones. This property is valuable when the degree of the polynomial is unknown. Finally, a simple empirical equation is given relating the precision of least‐squares‐calculated polynomial coefficients to the degree of the fitted polynomial and the number of effective decimal digits carried in the calculation.

ISSN:0021-8979    

DOI:10.1063/1.1713152

出版商:AIP    

年代:1964

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1713153

出版商:AIP    

年代:1964

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1713154

出版商:AIP    

年代:1964

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1713155

出版商:AIP    

年代:1964

数据来源: AIP