摘要:

Photoexcited carriers redistribute the charges in the space‐charge region of a semiconductor. The wavelength‐dependent photoeffect is most significant at low temperatures and strongly affects the modulating electric field in surface barrier electroreflectance (SBER). This work undertakes a study of this effect on SBER by making concurrent ac capacitance and conductance measurements in the MOS configuration and comparing the results with photoconductivity theory. The relationship between photocapacitance and the effective modulating electric field is investigated, providing herewith a better understanding of SBER at low temperatures.

ISSN:0021-8979    

DOI:10.1063/1.1662211

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Infrared transmission spectra of a series of SiO2films vapor deposited on silicon from SiH4and O2at 450 °C have been studied as a function of film thickness in the submicron range from 1000 to 9000 Å. Absorbances of band maxima observed in the frequency range 250–1400 cm−1are shown to obey the Lambert‐Bouguer's law in both as‐deposited and heat‐treated (800–1200 °C) materials. Apparent absorption coefficients calculated for the transmission mimima at 1060, 800, and 450 cm−1are 2.5 ± 0.1 × 104, 0.24 ± 0.02 × 104, and 0.74 ± 0.02 × 104cm−1for as‐deposited films and 3.4 ± 0.1 × 104, 0.34 ± 0.02 × 104, and 1.06 ± 0.02 × 104cm−1for heat‐treated films, respectively. The thickness of SiO2films as‐deposited at 450 °C as well as heat treated to 800 °C and above can be determined nondestructively using the present absorbance data.

ISSN:0021-8979    

DOI:10.1063/1.1662212

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

An instability mechanism for a pile‐up of perfect screw dislocations is investigated where the cross‐slip barrier is that of the Peierls‐Nabarro force. The pile‐up is found to reach a state of unstable equilibrium under the condition &tgr;* = 0.66(&mgr;s)1/2, where &tgr;* is the tip stress of the pile‐up, &mgr; the shear modulus, andsthe initial slope of the Peierls force. Satisfaction of this relation will lead to cross slip of the second dislocation resulting in a blunting of the pile‐up tip.

ISSN:0021-8979    

DOI:10.1063/1.1662213

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The use of a small amount of xylene as a gas additive to a SF6: H2mixture in an electrically initiated pulse HF chemical laser has been shown to increase laser peak power output. For the experimental conditions of this work, enhancement of output power was seen only for laser medium pressures greater than 200 Torr. A maximum increase in peak power of 60% was observed for a pressure of 300 Torr.

ISSN:0021-8979    

DOI:10.1063/1.1662214

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Evanescent field coupling is proposed as a practical way of coupling the output of a thin‐film laser to an optical waveguide. Relevant parameters are estimated for the case of a GaAlAs LOC laser coupled to a guide.

ISSN:0021-8979    

DOI:10.1063/1.1662215

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The classical theory of electric images is employed to calculate the image force work function of a dielectric layer on a conducting substrate. Theoretical results indicate that the work function should decrease with layer thickness and increase with dielectric constant. Correlated experimental data are offered in support of these conclusions.

ISSN:0021-8979    

DOI:10.1063/1.1662216

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The diffusion constantD(T) of cadmium into single‐crystal zinc selenide was measured using a photoluminescence/etch technique. Diffusions were performed in sealed ampoules using cadmium metal and cadmium selenide powder as dopant sources. For cadmium metal sourcesD(T) = 6.39 × 10−4exp(− 1.87 eV/k T) in the range 700–950 °C.

ISSN:0021-8979    

DOI:10.1063/1.1662217

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Fused quartz capillaries 700 and 1200 m long and 100 &mgr;m in inside diameter have been filled under hydrostatic pressure. It is verified that the rate of filling is governed by Poiseuille's law, which predicts the filled length to be proportional to the square root of the filling time. At a pressure of 270 atm, 250 m was filled in 1 h, 800 m in 10 h, and 1200 m in 21 h. The filling rate cannot be increased significantly from the above values by increasing the pressure because of the increase in the viscosity of the fluid with increasing pressure. Since it requires high pressure to move the liquid in a long capillary, it is apparent that liquid will not flow out of a long capillary that is not under pressure.

ISSN:0021-8979    

DOI:10.1063/1.1662218

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The theoretical model for a self‐pulsing ring laser has been modified by confining the active medium to a length less than the cavity length. Some of the results of this modification are reported in this paper. Also, a more general type of loss has been considered and the results are included.

ISSN:0021-8979    

DOI:10.1063/1.1662219

出版商:AIP    

年代:1973

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1662221

出版商:AIP    

年代:1973

数据来源: AIP