摘要:

Measurements are reported which show that a few tens of angstroms of an amorphous adlayer of silicon on a single‐crystal (111) silicon surface produces a measurable degradation in the pseudo‐Kikuchi backscattered electron pattern of this surface. Normalized pattern quality, as defined in this work, is shown to decrease rapidly with adlayer film thickness and to become effectively zero at 350 Å for a primary electron beam accelerating voltage of 21.3 kV. At 5 kV, the normalized pattern quality was effectively zero for all measurable film thicknesses (thickness measurement limit was ∼20 ± 20 Å).

ISSN:0003-6951    

DOI:10.1063/1.1652871

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

The breakdown voltage and the maximum electric field of AlxGa1−xAs avalanche diodes are presented as a function of the aluminum content in the samples. Aluminum content is estimated from the actual weight ratio of Al and Ga and the band gap energy of the samples. The maximum electric fields are calculated from the measured data of the breakdown voltage, capacitance at breakdown, and diode dimensions. Experimental results indicate that in addition to its function of increasing the band gap energy, increased Al contents also reduce the impurity gradient of the diodes. As a result, the breakdown voltage is found to increase more rapidly than the maximum electric field, when the Al content is increased. Values of maximum electric field in the range from 6 to 8 × 105V/cm are observed. These values compare favorably with those of GaAs and GaP.

ISSN:0003-6951    

DOI:10.1063/1.1652872

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Optical second‐harmonic generation has been observed in crystals of six organic dyes. One dye, 7‐diethylamino‐4‐methylcoumarin, appears to be at least as good a frequency doubler as LiNbO3and has a much higher resistance to surface damage.

ISSN:0003-6951    

DOI:10.1063/1.1652873

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Optical third harmonic generation in ADP crystals has been studied both in reflection and along the phase‐matched direction. Results with a mode‐locked laser indicate that only a small fraction (∼4%) of the total energy per laser shot was associated with the picosecond spikes in the laser output. This suggests that the peak power associated with the picosecond pulses may have been grossly overestimated in some cases.

ISSN:0003-6951    

DOI:10.1063/1.1652874

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

An infrared point‐contact diode is used to mix the frequency of a 28.0 &mgr; water laser with that of a 9.3 &mgr; CO2laser and aK‐band microwave radiation. The experiment provides, among several applications, the crucial link necessary to establish a frequency multiplier chain for absolute frequency measurements in the infrared.

ISSN:0003-6951    

DOI:10.1063/1.1652875

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

The reaction F + HCl → HF†+ Cl has been used to produce cw chemical laser action. This has been accomplished by mixing two supersonic streams of the reactant species in a shock tunnel. The time duration of the laser action is two orders of magnitude longer than the natural laser pulse in a non‐flowing system, i.e., it is limited only by the flow time of the shock tunnel.

ISSN:0003-6951    

DOI:10.1063/1.1652877

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Acoustic surface wave phase velocities have been measured on (001), (110), and (111) surfaces of single‐crystal silicon using the wedge method. Good agreement between the theoretical and experimental results was obtained.

ISSN:0003-6951    

DOI:10.1063/1.1652878

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Electromodulation of the interference spectrum of thin anodized Ta2O5films is analyzed by means of multiple interference theory. The analysis confirms that the dominant effect is an electro‐optic modulation of the refractive index of the film, rather than electrostriction. It is also found that the electro‐optical behavior is similar to that shown by oxygen‐octahedra ferroelectriclike single crystals.

ISSN:0003-6951    

DOI:10.1063/1.1652879

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Experimental results of the effects on charge storage in the MNOS structure by varying the growth temperature of the silicon nitride are presented. The range of growth temperature examined is 650–1100°C. The initial charge stored is positive at the lower temperatures, negative at the higher temperatures. The maximum positive charge that can be stored varies continuously with growth temperature. The ability to retain the stored charge when the charging voltage is removed decreases monotonically with increasing growth temperature.

ISSN:0003-6951    

DOI:10.1063/1.1652880

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Epitaxial &bgr;‐SiC films have been formed on sapphire by chemical conversion of thin single‐crystal Si‐on‐sapphire films. The conversion is obtained by reaction of C2H2with Si within the temperature range 900–1200°C. It is observed that epitaxy persists up to a certain depth, beyond which film orientation degenerates. The growth morphology of the &bgr;‐SiC films appears to be related to surface granularity of the Si films and differs from that observed for conversion of bulk Si.

ISSN:0003-6951    

DOI:10.1063/1.1652881

出版商:AIP    

年代:1969

数据来源: AIP