摘要:

Conducting (10−1&OHgr; cm) pathways have been directly written into an insulating (106&OHgr; cm) diamondlike carbon film using pulsed laser irradiation (0.53 &mgr;m). The morphological and structural changes caused by the laser suggest that the film has been transformed into a form of graphite preserving some of the diamondlike properties of the original coating.

ISSN:0003-6951    

DOI:10.1063/1.96876

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

High‐temperature x‐ray diffraction measurements on HgTe‐CdTe superlattices grown by molecular beam epitaxy have been made to determine the extent of intermixing of the individual HgTe and CdTe layers.Insituinterdiffusion measurements were carried out at 110, 162, and 185 °C and estimates of the interdiffusion coefficient were made. We find appreciable intermixing of the HgTe and CdTe layers at temperatures as low as 110 °C. Such results have serious implications for the use of this material in optoelectronic devices.

ISSN:0003-6951    

DOI:10.1063/1.96877

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Evidence of instability of TiSi2layers during high‐temperature high vacuum annealing has been observed. Rutherford backscattering and scanning electron microscopy measurements showed that at high vacuum annealing conditions, the laterally homogeneous silicide layer breaks up into islands. In between these TiSi2islands, growth of an epitaxial silicon layer was observed.

ISSN:0003-6951    

DOI:10.1063/1.96826

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

High‐temperature heat treatment of a heat‐resistant, condensation polymer poly ( &rgr;‐phenylene‐1,3,4‐oxadiazole) yielded a large‐area, flexible film composed of highly oriented and nearly ideal graphite crystallites. The graphitic behavior was exemplified by both the (002) lattice spacing of 3.354 A˚ and extremely small full width at half‐maximum intensity of the (002) reflection, 0.16–0.17°, for the films heat treated above 2800 °C.

ISSN:0003-6951    

DOI:10.1063/1.96827

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

An ultrahigh vacuum scanning tunneling microscope (STM) equipped with a field ion microscope (FIM) has been built. By using the FIM image, a tungsten tip was tailored for high STM resolution in a scan of the Au(001) surface. The measured corrugation depth of the (1×5) rows was found to be a function of the size of the atomic cluster on the first plane of the tungsten tip.

ISSN:0003-6951    

DOI:10.1063/1.96828

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Medium energy ion scattering studies show that material reactions other than interfacial silicide formation dominate the low‐temperature reactivity of the Ti/Si interface. This provides an explanation for the anomalous kinetics and considerable extent (100 A˚ or more) of reaction of refractory metals with Si, which are observed well below the temperatures normally associated with silicide growth in thicker films.

ISSN:0003-6951    

DOI:10.1063/1.96829

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Electron diffraction measurements on (100) GaAs1−xSbxlayers withx≊0.5 grown by organometallic vapor phase epitaxy indicate that ordered phases are formed during growth. Two ordered phases are observed. The simple, tetragonal AuCu‐I type phase consists of alternating {100} oriented GaAs and GaSb layers. Only the two variants with the tetragonalcaxes perpendicular to the growth direction are observed. At least two variants are observed for the chalcopyriteE11structure with alternating {210} oriented GaAs and GaSb layers.

ISSN:0003-6951    

DOI:10.1063/1.96830

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

We report the use of wavelength‐modulated photocurrent spectroscopy to obtain detailed information on quantum well transitions in an In0.14Ga0.86As/GaAs strained‐layer superlattice. The spectra are interpreted in terms of a Kronig–Penney model with literature values for offsets and deformation potentials. The effect of the test structure’s built‐in electric field must be included to obtain agreement with this theory.

ISSN:0003-6951    

DOI:10.1063/1.96831

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

‘‘Ballistic’’ electron transistors are of considerable interest for high‐frequency operation. Regardless of the mechanism of electron injection or collection it is anticipated that device performance will be dominated by base transit dynamics. We address this issue by calculating the scattering rate for hot electrons in selected semiconductor materials holding some common band structure and transport properties. It is shown that the scattering rate is critically dependent on the carrier concentration and that GaAs is not suitable for fabrication of traditional ‘‘ballistic’’ electron transistors. We suggest that semiconductors with small effective electron mass or a two‐dimensional system would be more suitable.

ISSN:0003-6951    

DOI:10.1063/1.96832

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Layer‐by‐layer alternating surface reconstructions of Si(001) 2×1 and 1×2 have been observed for the first time using reflection high‐energy electron diffraction (RHEED) during molecular beam epitaxy. RHEED intensity oscillations of the specular beam and two kinds of reconstruction related spots have been monitored simultaneously. It was found that stable alternating reconstructions can be observed on the surface with a single‐domain 2×1 structure obtained by high‐temperature annealing. One period of the RHEED intensity oscillation observed for the specular beam during the growth corresponds to a monatomic layer or a biatomic layer height depending not only on the electron beam incident azimuth but also the glancing angle.

ISSN:0003-6951    

DOI:10.1063/1.96833

出版商:AIP    

年代:1986

数据来源: AIP