摘要:

The dislocation climb mechanism for the growth and morphology of copper precipitates in silicon, as proposed by Fiermans and Vennik, is questioned on a number of points. In particular, the regularity of the geometry of precipitate colonies, the variation in precipitate density within a colony, and the different morphologies of precipitates of various interstitial impurities in silicon are cited against the suitability of the mechanism.

ISSN:0021-8979    

DOI:10.1063/1.1662578

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Evidence is presented defining the reaction of free MgO in MgAl2O4spinel powder with molybdenum crucibles under reducing conditions prior to crystal growth using the gradient furnace technique. This reaction results in strongly colored crystals but can be eliminated by sufficient heat treatment of the spinel powder to incorporate all the MgO into the spinel structure before melting.

ISSN:0021-8979    

DOI:10.1063/1.1662579

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The limitations of the ``static equilibrium'' method for the simulation of dislocation motion are pointed out, emphasizing that the previously applied ``equation of motion'' method suffers from less severe restrictions.

ISSN:0021-8979    

DOI:10.1063/1.1662580

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

It is shown that the selection of an applied stress as a dependent or as an independent variable in dislocation equilibrium calculations limits their applicability to constant strain‐rate tensile or creep tests, respectively. Furthermore, it is shown that equilibrium calculations based on force techniques may not represent realistic configurations since the force techniques cannot incorporate in their formulation the history dependence of the equilibrium configuration, whereas the energy minimization techniques can.

ISSN:0021-8979    

DOI:10.1063/1.1662581

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

As a new method of making high‐quality and high‐storage‐density holograms capable of storing such image information as pictures and portraits, combination of the sampling method and random phase shifter method is proposed. This method reduces the concentrations of information light energy on the hologram plane which are located evenly in the just Fourier‐transformed plane. As an experimental result, the light waves passing through 106sampling points on a frame information with random phases were focused into a spot to make a hologram of 2.0‐mm diameter. The reconstructed image from the hologram showed high quality without speckle and high efficiency.

ISSN:0021-8979    

DOI:10.1063/1.1662582

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Values of the elastic constant of CaMoO4obtained by Alton and Barlow are compared with those obtained using equations developed by Chung and Li. The velocities measured by Alton and Barlow were used in the computations.

ISSN:0021-8979    

DOI:10.1063/1.1662583

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A calculation is presented to estimate the effect on silicon surface mobility of the potential fluctuation due to a random distribution of localized charges near the interface. With a choice of reasonable values for two parameters, the mean—square charge deviation and the correlation length, the theoretical mobility agrees rather well with experiments at low gate voltage and very low temperatures.

ISSN:0021-8979    

DOI:10.1063/1.1662584

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Measurements of the electrical conductivity and the Seebeck effect in (V0.3Nb0.3)O2are reported. A semiconductor‐to‐metal transition is observed at about 1000°K and an evaluation of the activation energy for the electron mobility gives 0.05 eV.

ISSN:0021-8979    

DOI:10.1063/1.1662585

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The dependence of the optical absorption of polyethylene on photon energy is analyzed and correlated with electrical conduction. The optical gap is obtained as 7.35 eV, with a band tail of about 1 eV. Electrons transport by hopping according to &mgr;0exp(−E&mgr;/kT), where &mgr;0= 5 cm2/V sec andE&mgr;= 0.24 eV at 20–80°C. Electrons are supplied from deep donors which lie at 2 eV and more below the conduction band. The deep donors are considered to be responsible for the increase in the conductivity at high field, which might be explained by the Poole‐Frenkel effect.

ISSN:0021-8979    

DOI:10.1063/1.1662586

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Time‐of‐flight electron drift velocity measurements have been made for Si between 300 and 415 °K in the range of electric fields near the velocity saturation knee. The results show a more pronounced decrease from saturation values at the higher temperatures.

ISSN:0021-8979    

DOI:10.1063/1.1662587

出版商:AIP    

年代:1973

数据来源: AIP