摘要:

In this letter, a decimal adder using single electron transistors as a building block is presented. The design is described and the equivalent circuit is extracted, from which the dc performance of the adder is derived. This simple analytical approach is found to be in good agreement with numerical simulation. A detailed sensitivity analysis is performed where the effects of temperature, capacitance, conductance, and background-charge variations are analyzed and the attendant change in device performance is described. This adder needs a number of wires four times less than binary adders and hence alleviates the interconnections problem present in high density circuits. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.118934

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

The effect on the thermal and dielectric properties of incorporating benzene rings in hydrogenated amorphous carbon(a-C:H) films was investigated. The benzene rings were introduced intoa-C:H films by using plasma-enhanced chemical vapor deposition and aromatic source compounds. Thea-C:H film that contained benzene rings had thermal stability up to 400 °C and a low-dielectric constant of 3.0. The difference in the dielectric constant and thermal stability ofa-C:H films appeared to be due to the hydrogen concentration of the films. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.118935

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

The optical properties of the regular, 3-nm-wide hexagonal channels of the mesoporous silica molecular sieve (MCM–41) containing C60are reported. Besides an intensive photoluminescence response at 642 nm from confined C60,a more intensive photoluminescence at 484 nm has been observed, which is considered to result from the passivation of silica zeolite with C60.Our studies indicate that both the properties of guest and host can be modified due to the interaction at the interface of them. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.118936

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

We report the synthesis of thin films of the conducting cubic oxideSr0.7NbO3by pulsed laser deposition. Deposition conditions were investigated and optimized to yield both conductivity and crystallinity. Unlike most similar materials we find that successful synthesis of conductingSr0.7NbO3is very sensitive to oxygen pressure during deposition. Optimal properties were obtained for vacuum deposition at a substrate temperature of 750 °C. Typical resistivity was 800 &mgr;&OHgr; cm at 300 K and independent of temperature down to 10 K. Films grew epitaxially onto {100} MgO. Functionality of the material was demonstrated by preparing MgO/Sr0.7NbO3/BaTiO3/Au capacitors. Despite their apparently excellent lattice match, these capacitors exhibited depressed Curie temperatures. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.118937

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

We use an ultrafast scanning tunneling microscope to resolve propagating voltage transients in space and time. We demonstrate that the previously observed dependence of the transient signal amplitude on the tunneling resistance was only caused by the electrical sampling circuit. With a modified circuit, where the tunneling tip is directly connected to the current amplifier of the scanning tunneling microscope, this dependence is eliminated. All results can be explained with coupling through the geometrical capacitance of the tip-electrode junction. By illuminating the current-gating photoconductive switch with a rigidly attached fiber, the probe is scanned without changing the probe characteristics. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.118938

出版商:AIP    

年代:1997

数据来源: AIP