摘要:

A novel use of a staircase voltage waveform shows that three light emission peaks can be produced with a unipolarity voltage pulse in alkaline‐earth‐sulfide electroluminescent devices. Two peaks following the voltage decrease demonstrate the following: Light can be produced at fields much below those required for hot‐electron effects. Activators are ionized when a field is applied. Recombination controls electroluminescence.

ISSN:0003-6951    

DOI:10.1063/1.98131

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Tunable and continuous wave (cw) near infrared up‐conversion into the dark blue wavelength range (410–465 nm) has been achieved in KNbO3crystals using the nonlinear optical coefficientd32(&ohgr;1+&ohgr;2; &ohgr;1,&ohgr;2)=20.4 pm/V. High efficiencies have been reached due to the large nonlinearity and the possibility of temperature‐tuned noncritical 90° phase matching. Using a neodymium:yttrium aluminum garnet laser (1064.2 nm) as the signal source and a krypton laser (676.4 nm) as the pump source, a sum signal (413.6 nm) power of over 0.1 mW was reached at a pump power of only 26.2 mW. cw image up‐conversion into the blue wavelength range has been demonstrated using a noncritically phase‐matched configuration in the same crystals atT=−4 °C.

ISSN:0003-6951    

DOI:10.1063/1.98132

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

A rapidly converging iterative method based on deconvolution techniques is proposed for the computation of the inverse Abel transform. The calculations only involve repeated applications of the forward Abel transform and no derivatives are needed. The iterative method is shown to be less susceptible to noise amplification when compared with other techniques.

ISSN:0003-6951    

DOI:10.1063/1.98133

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Fluorinated silicon nitride films are deposited by the plasma enhanced reaction of SiH4‐NH3‐NF3gas mixtures. The deposition rate with NF3increases to a maximum of approximately six times that of SiNxHydeposited using only SiH4and NH3. Optical and electrical properties of the SiNxHyfilms are also affected. The addition of NF3to the deposition atmosphere significantly reduces the concentration of H bonded to Si. The films display dielectric properties similar to SiNxHyfilms deposited using SiH4and NH3. All films containing F hydrolyze on exposure to air. When less than 10 at. % F is present in the as‐deposited films, film stability is achieved after initial hydrolysis. Essentially total hydrolysis to SiO2occurs when the F content exceeds 10 at. %.

ISSN:0003-6951    

DOI:10.1063/1.98134

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

cw CO2laser‐assisted combustion of Ti and Zr in Xe:O2and N2:O2gaseous mixtures was studied. Total dissolution of oxide films and/or formation of oxynitride layers on both metals were evidenced and the growth of giant oxide nuclei of up to 100×10×10 &mgr;m3was observed upon burning Zr samples.

ISSN:0003-6951    

DOI:10.1063/1.98135

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Differential scanning calorimetry (DSC) has been used to study solid‐state amorphization and subsequent crystallization in sputtered multilayer Ni/Zr thin films. Initial results provide quantitative information about the thermodynamics and kinetics of these processes. An analysis of DSC data enables the activation energy and pre‐exponential factor for interdiffusion of Ni and Zr ina‐NiZr to be found.

ISSN:0003-6951    

DOI:10.1063/1.98136

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

The need to fashion materials on a submicron scale is now well recognized. In a scanning tunneling microscope we have been able to achieve nanometer scale control of the depth of penetration of the probe into a thin insulating film, and by laterally traversing the probe we have been able to machine away submicron‐wide, 20‐nm‐thick strips of the insulating film without damage to the substrate or probe. This could represent a new approach to ultrafine machining. However, the detailed mechanism of how the tunneling current through the film can be used to control the machining depth is still unclear.

ISSN:0003-6951    

DOI:10.1063/1.98137

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

The mixing of Ti, Cr, and Ni thin films with SiO2by low‐temperature (−196–25 °C) irradiation with 290 keV Xe has been investigated. Comparison of the morphology of the intermixed region and the dose dependences of net metal transport into SiO2reveals that long range motion and phase formation probably occur as separate and sequential processes. Kinetic limitations suppress chemical effects in these systems during the initial transport process. Chemical interactions influence the subsequent phase formation.

ISSN:0003-6951    

DOI:10.1063/1.98138

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

It is shown thatlocaltetragonal distortion in a Si Ge0.05Si0.95strained‐layered structure can be detected and quantified from analyses of the high‐order Laue zone lines which are present in the bright‐field disks of [001] convergent‐beam electron diffraction patterns. The detection of a tetragonal distortion is based on symmetry arguments, whereas the quantification requires a detailed analysis which is based on computer simulated patterns, assuming a kinematical approximation of the scattering process and including surface relaxation. The result of this quantitative analysis is in good agreement with the tetragonal distortion which is predicted by isotropic elasticity theory.

ISSN:0003-6951    

DOI:10.1063/1.98139

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

It has been found that annealing Pd‐Er deposits on a (001) silicon surface results in the formation of isolated submicron islands of Pd2Si with two epitaxially oriented habits. By contrast, when Pd is annealed on a (111) silicon substrate, Pd2Si is formed with full coverage and a specific epitaxy.

ISSN:0003-6951    

DOI:10.1063/1.98140

出版商:AIP    

年代:1987

数据来源: AIP