摘要:

This paper reports new experimental results on the measurements of oxygen and carbon in silicon.18O and13C in‐depth distribution has been measured in silicon as a function of postimplant furnace and laser annealing using secondary ion mass spectroscopy. Analysis shows that a complicated structure appears in the18O atomic profile following 900–1100 °C furnace annealing. The18O redistribution is substantially caused by implantation‐induced damage gettering of18O in silicon. Because of a fast annihilation of displacement damages by laser annealing, any complicated redistribution was not observed in the laser‐annealed18O atomic profile. No such structure was observed in the furnace‐ and laser‐annealed13C atomic profiles, implying some differences in the atomic behavior of carbon and oxygen in silicon.

ISSN:0021-8979    

DOI:10.1063/1.328073

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The effect of elastic anisotropy on the stability of extended dislocation barriers at coherent twin boundaries in face‐centered cubic metals has been determined. It is shown that the nature of the symmetry associated with the twin boundary is such that no image forces are developed on dislocations lying parallel to the boundary. It is found that the results are in qualitative agreement with earlier isotropic results.

ISSN:0021-8979    

DOI:10.1063/1.328074

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Previous ultrasonic measurements have shown a softening of one of the acoustic‐phonon branches in thallium phosphorus selenide (Tl3PSe4) when subject to hydrostatic pressure. These measurements also show a 60% softening between room temperature and 90 K. In order to further characterize this material and to investigate the possibility of a phase transition at temperatures less than 90 K, we have used inelastic neutron scattering to measure the phonon dispersion along symmetry directions. The measurements agree well with the ultrasonic measurements previously reported for all branches except the soft ab shear described by the strain componente6. The ab shear is found to be 60% stiffer than the ultrasonic value with very little temperature dependence.

ISSN:0021-8979    

DOI:10.1063/1.328075

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The controversial phase transitions in barium and bismuth were studied with a manganin coil sensor. The transition in barium proposed at 80 kbars by Bastideetal. was confirmed at 95 kbars. For bismuth, the transition reported first by Bridgman around 45 kbars was confirmed at 40 kbars, but that around 65 kbars could not be detected. To make up theP‐Tdiagram of barium, the confirmed transition and the so‐called high‐Ba transition were traced at elevated temperatures by the resistance anomaly of barium, and the melting points above 90 kbars were determined with a manganin ribbon sensor. The mechanism of the manganin sensor is discussed with regard to the volume change associated with a transition.

ISSN:0021-8979    

DOI:10.1063/1.328076

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

A model for arsenic diffusion in silicon is proposed based on Hu’s theory which takes into account the degeneracy of the mobile carriers, partial ionization of the impurity atoms, single acceptor level vacancies, and the internal electric field. For a constant source diffusion, the transport equation describing the As+‐V−system can be separated. An efficient computer program based on a quasilinearization technique is written to obtain the impurity profiles from the processing data. It is shown that partial ionization significantly affects the diffusion process at high concentrations. The use of classical statistics yields an underestimate of the impurity concentration values. The computed profiles strongly depend on the values used for the intrinsic diffusion coefficient and vacancy energy. There is very good agreement between the vacancy‐aided model and experimental results reported by Chiu and Ghosh using neutron activation analysis.

ISSN:0021-8979    

DOI:10.1063/1.328077

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Shallow (<0.2 &mgr;m)n+layers in Si with high conductivity (<40 &OHgr;/&laplac;) have been formed by high‐dose (2×1016cm−2) As implants. Experimental observations of As distributions and carrier concentrations are successfully simulated by a computer program which accounts for both the concentration dependent diffusion and As clustering effects. Reduction of electrical carriers in high‐dose As implanted Si during moderate temperature (∼800 ° C) heat treatments is readily explained by the kinetics of As clustering. Physical limitations on the conductivity which can be achieved by thermally annealed As implants in Si are also discussed.

ISSN:0021-8979    

DOI:10.1063/1.328078

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Single‐crystalline Mn‐, Ni‐, and Al‐substituted copper ferrite films are grown by the LPE method from a PbO‐B2O3flux on (111)‐MgO substrates. Solid solutions between copper ferrite and Mn3O4, NiFe2O4, and CuAl2O4are obtained. The segregation coefficients for Ni and Al are shown to be linearly dependent on the growth temperature. From domain‐structure observations and from torque measurements it is concluded that a positive uniaxial anisotropy is present in the copper ferrite films. After stress relief at the deposition temperature a stress develops during cooling to room temperature due to a difference in thermal expansion coefficients of film and substrate. This stress is responsible for the observed anisotropy.

ISSN:0021-8979    

DOI:10.1063/1.328079

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Oxidation characteristics of the tantalum disilicide films have been investigated in the temperature range of 900°–1050 °C in dry oxygen and steam ambients. The silicide does not oxidize in dry oxygen and oxidizes in steam at a rate lower than that of doped polycrystalline silicon films as long as there is a polycrystalline silicon layer between the silicide and the gate oxide. Under these circumstances, the silicide retains its electrical and mechanical characteristics. The oxide on the silicide has an etch rate (in buffered hydrofluoric acid) similar to that of thermal SiO2on silicon. Electrical characteristics of the oxide appear to be similar to those of the wet oxide on polycrystalline silicon. In the absence of polycrystalline silicon, between the silicide and the gate oxide, oxidation leads to a loss in the conductivity of the silicide and eventually to a mechanical instability of the film. An oxidation mechanism, which assumes silicon diffusion by substitution through the silicide, has been proposed.

ISSN:0021-8979    

DOI:10.1063/1.328080

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The pressure induced metallic state of Se, Te, and Si has been studied using a cryogenic clamp press. The resistance versus temperature curves were analyzed and used for derivation of the characteristic temperature &Vthgr;. Good agreement was obtained between the experimental results and the Gru¨neisen‐Bloch relation for the resistance of metals.

ISSN:0021-8979    

DOI:10.1063/1.328081

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

p‐type InSb crystals have been obtained by annealingn‐type InSb crystals at 350 °C in vacuum (10−5Torr) for different durations. The dc Hall effect and conductivity studies have shown that the inversion temperature increases with increase in annealing time, whereas the Hall mobility decreases. The ratio of electron to hole mobilitybis calculated from the logRH‐vs‐1/Tcurve and also from electron and hole concentrations. The ratiobis also calculated theoretically from electron and hole mobilities. The valuebobtained from experiments is found to differ from thebcalculated theoretically. This discrepancy has been attributed to the scattering of charge carriers by dislocations produced during annealing. Using the Dexter and Seitz mechanism [Phy. Rev. 86, 964 (1952)] the dislocation densities have been estimated in the annealed samples.

ISSN:0021-8979    

DOI:10.1063/1.328082

出版商:AIP    

年代:1980

数据来源: AIP