摘要:

When solid GaAs is placed in an undersaturated solution of Ga, Al, and As, it has been observed that a layer of the solid Ga1−xAlxAs forms on the surface. In the past the presence of this layer has been attributed to a process of regrowth following sufficient dissolution to saturate the solution. On the other hand, an analysis of the kinetics of the situation has suggested that dissolution should be continuous and that the surface layer is formed by solid diffusion. An experiment is reported here in which the solid is forced to dissolve continuously, and a layer of Ga1−xAlxAs of similar thickness to those reported by others has been found to be produced on the surface. Such a layer could not have been produced by regrowth. In order to be produced by solid diffusion, the diffusion coefficient of Al in GaAs must be anomalously high.

ISSN:0003-6951    

DOI:10.1063/1.91096

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

The silicon self‐diffusion in intrinsic silicon was investigated by a new method using stable isotope30Si and the ion‐analyzer technique. The temperature dependence of the diffusion coefficient was obtained in the range from 885 to 1175 °C from which an activation energy 110.6 kcal/mole was obtained.

ISSN:0003-6951    

DOI:10.1063/1.91097

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Thermally induced microdefect formation phenomena are investigated in connection with oxygen and carbon in silicon crystals by using x‐ray diffraction, infrared absorption, and etching/optical microscope observation techniques. In order to investigate the carbon and oxygen role for microdefect formation, oxygen‐diffused floating‐zone‐grown silicon crystals, containing various carbon contents, are thermally treated. As a result, it is ascertained that the coexistence of both carbon and oxygen is necessary for the microdefect formation. It is also determined that the critical oxygen concentration for microdefect introduction by the heat treatment is about (5–6) ×1017cm−3.

ISSN:0003-6951    

DOI:10.1063/1.91098

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

The reflection acoustic microscope has been used to measure SAW velocity dispersion and to indirectly measure the film thickness in a layered composite consisting of Au on a Si substrate. A quantitative thickness determination was made via the acoustic material signature technique, that is nondestructive and noncontacting. A theoretical prediction of SAW dispersion is in excellent agreement with these measurements.

ISSN:0003-6951    

DOI:10.1063/1.91099

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A theoretical study of the surface‐acoustic‐wave (SAW) properties of quartz has produced a new cut which is temperature compensated along two orthogonal directions. This new cut is attractive for use in reflection‐grating devices such as the reflective array compressor (RAC), in which orthogonal propagation paths are required. Except for a small electromechanical power flow angle, the SAW properties along the two temperature‐compensated directions are similar to those of x‐propagatingST‐cut quartz. Because the attractive propagation paths lie in the plane of a singly rotated crystal cut, it should be relatively easy and inexpensive to manufacture.

ISSN:0003-6951    

DOI:10.1063/1.91100

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

We present measurements of the spin polarizationPof photoelectrons from negative electron affinity (NEA) GaAs (100) and findP=43% at a photon energy of 1.57 eV. This contrasts with a maximumP=21% measured by Erbudak and Reihl for NEA GaAs (110), which led them to conclude that NEA and highPexclude each other. This difference inPis important for sources of polarized electrons employing photoemission from GaAs. We suggest that the origin of this difference may be connected with differences in the photoelectron emission process at the two faces, as calculated by Burt and Inkson.

ISSN:0003-6951    

DOI:10.1063/1.91101

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

The effect of Ar‐ion bombardment on evaporated–Nb‐on‐Si systems has been investigated with He backscattering and x‐ray‐diffraction measurements. High‐dose bombardment with energetic Ar ions was found to induce intermixing between Nb and Si in the form of NbSi2. This effect has strong dependence on temperature during bombardment, although it cannot be explained as enhanced diffusion due to radiation damage or ion‐beam heating.

ISSN:0003-6951    

DOI:10.1063/1.91102

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Formation of PdSi has been obtained by implanting energetic Xe ions through a thin Pd (or Pd2Si) film on a Si substrate. The PdSi phase was found to form near the Pd2Si‐Si interface from Rutherford backscattering measurements. Phase formation was confirmed by glancing‐angle x‐ray‐diffraction analysis. Subsequent thermal annealing at 300–400 °C resulted in successive growth of the phase. A uniform PdSi layer was obtained at the final stage of the annealing and exhibited a sheet resistivity of 18 &mgr;&OHgr; cm.

ISSN:0003-6951    

DOI:10.1063/1.91103

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Annealing behavior of phosphorus implanted in silicon layers under cw CO2laser irradiation is investigated. The irradiation time required for full electrical activation is found to depend on the dopant concentration of the substrate. This is because absorption of CO2laser light is a function of free‐carrier concentration in the crystalline substrate. During the experiment, an enhancement of annealing efficiency is observed in the case of a low‐resistivity substrate or with bias light (Xe lamp) irradiation. This supports the above explanation.

ISSN:0003-6951    

DOI:10.1063/1.91079

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Large increases in the efficiency of the conventional P1 phosphor (Zn2SiO4 : Mn) have been achieved by substituting various combinations of III and V oxides for SiO2, e.g., Zn2−yMnySi1−2xAlxPxO4. The photoluminescence efficiency of these phosphors exhibit strong dependence on the AlPO4substitution concentrationxhaving highest efficiency forx=0.5–1.5%. Cathodoluminescence and decay measurements show that such materials can have CL efficiency greater than the commercial zinc silicates and still have comparable persistence characteristics.

ISSN:0003-6951    

DOI:10.1063/1.91080

出版商:AIP    

年代:1979

数据来源: AIP