摘要:

The negative shifts of the threshold voltages of75As+‐implanted Mo‐gate metal‐oxide semiconductor (MOS) transistors were observed under some fabrication conditions of high‐energy or high‐dose75As+implantation, or thin‐Mo‐film deposition. These phenomena are attributed to75As atoms entering Si through Mo‐film and ‐gate oxide by measuringC‐Vcharacteristics and observing the stain‐etched cross sections of the samples directly. The present threshold voltage shifts can be almost perfectly suppressed by covering Mo‐gate electrodes with 2000‐A˚ plasma‐CVD silicon‐nitride films during75As+implantation.

ISSN:0021-8979    

DOI:10.1063/1.329813

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A systemtic study of spectral responsivity, quantum efficiency, carrier concentration, zero‐bias resistance, and capacitance‐voltage characteristics of LPE‐grown PbTe‐Pb0.8Sn0.2Te heterosturcture diodes is presented as a function of the PbTe growth temperature, 420 °C<T<650 °C. The results provide clear evidence for the migration of thep‐njunction into thePbTe layer owing to interdiffusion of native defects across the interface during PbTe growth atT≳480 °C. The main effects of the junction migration on the diode characteristics are a reduction in the wuantum efficiency at wavelengths above the 6 &mgr;m and an increase in the junction zero‐bias resistance. These results are interpreted on the basis of the energy‐band diagrams of the heterostructure diodes obtained from the capacitance‐voltage characteristics and the measured carrier concentration of the epilayers. It is shown that an energy barrier for the excited electrons in the Pb0.8Sn0.2Te layer, formed at the PbTe‐Pb0.8Sn0.2Te interface, is responsible for the reduction of the photosignal above 6 &mgr;m. The junction migration is prevented by growing the PbTe layers below 480 °C. In this case, peak (∼10 &mgr;m) current responsivity in the range 1.7–2.3 A/W, quantum efficiency in the range 22–30% (both without an antireflection coating), andR0A≳1 &OHgr; cm2are reproducibly obtained.

ISSN:0021-8979    

DOI:10.1063/1.329815

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The recent report of cw nuclear‐pumped lasing and of the measurement of gain on the 3s2‐2p4transition of Ne in mixtures of 3He‐Ne by Carter, Rowe, and Schneider has some fundamental problems which lead one to conclude that the oscillation observed was not from the 6328‐A˚ line of Ne. Specifically, calculations using a very optimistic model of the He‐Ne laser at the reported conditions do not support the conclusions of Carteretal. The maximum possible small signal gain for the idealized system, which is the upper limit on this quantity, is an order of magnitude smaller that that reported. Additionally, due to the unusually high single‐pass cavity losses reported (≳50%), the idealized system could not achieve oscillation.

ISSN:0021-8979    

DOI:10.1063/1.329816

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

An oscillation has been found in the resistivity of gas sensing devices of sintered SnO2mixed with Pd, Rh, and MgO exposed to H2gas in air. This phenomenon depends on the H2gas concentration, the working device temperature, and the voltage applied to the device. Its waveforms consist of two structures and are conspicuously noticeable at 92 °C device temperature and 40 V voltage applied across the device.

ISSN:0021-8979    

DOI:10.1063/1.328433

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

We show both theoretically and experimentally that under essentially all conditions of experimental interest, the thermal contact resistance between sample and gas plays a negligible role in photoacoustic spectroscopy of solids.

ISSN:0021-8979    

DOI:10.1063/1.328435

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The dependence on the thermal properties of the gas in a photoacoustic cell predicted by the sample‐gas thermal resistance theory is also predicted by the Rosencwaig‐Gersho theory for very thin samples.

ISSN:0021-8979    

DOI:10.1063/1.328436

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A new monolithic ZnO on Si, narrow‐waveguide storage correlator has been demonstrated. A 100‐&mgr;m‐wide top‐plate electrode served as a &Dgr;v/vwaveguide for the 100‐&mgr;m‐wide acoustic beam. The surface acoustic wave itself was excited by interdigital transducers that were the same width as the waveguide electrode. Operation of this device resulted in a correlation efficiency ofFcorrT=−53 dB m, which is 13 dB better than that reported for any other ZnO on Si storage correlator.

ISSN:0021-8979    

DOI:10.1063/1.328437

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Colored drops falling only a short distance into clear liquid form vortex rings. A numerical study using the Marker and Cell technique predicted instead a jet rising from the cavity formed by the impact.

ISSN:0021-8979    

DOI:10.1063/1.328438

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

We describe how to choose the most stable of several equilibrium states that may exist in a liquid‐crystal cell at the same voltageV(or chargeQ). Among states that exist at the same chargeQ, the state with the lowest total free energyFis the most stable. Among states that exist at the same voltageV, the state with the lowest electric Gibbs function (F−QV) is the most stable. Thus the relative stability of various equilibrium states can be compared by plottingGagainstVorFagainstQ. An example is given to illustrate the importance of a correct pairing of thermodynamic functions and independent variables.

ISSN:0021-8979    

DOI:10.1063/1.328427

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Films with modulated composition 8‐A˚ Cu/8‐A˚ Ni show an increase in the Young’s and torsional moduli of a factor of 2, relative to bulk or longer‐wavelength samples. The film structure is found to be highly textured with coherent lamella for the short‐wavelength‐enhanced moduli samples, but becomes more random with the probable introduction of misfit dislocations at longer wavelengths. The moduli results support the previous findings of Tsakalakos and Hilliard. 

ISSN:0021-8979    

DOI:10.1063/1.329796

出版商:AIP    

年代:1981

数据来源: AIP