摘要:

Room‐temperature continuous operation (cw, 300 °K) of photopumped AlxGa1−xAs‐GaAs‐AlxGa1−xAs quantum‐well heterostructure lasers embedded in Cu under diamond windows is demonstrated. The quantum‐well heterostructures are grown by metalorganic chemical vapor deposition (MO‐CVD) and possess undoped (nd−na≲1015/cm3) or compensated (nZn∼1019/cm3,nSe∼8×1018/cm3) GaAs active layers of thicknessLz∼200 A˚.

ISSN:0003-6951    

DOI:10.1063/1.90150

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The utilization of WSi2thin films as gate electrodes in field‐effect transistors depends on the ability of this material to form a continuous electrically insulating SiO2overlayer. In the steam oxidation of WSi2films deposited on polysilicon, SiO2forms on the surface by means of the rapid diffusion of Si through the WSi2which appears in this case to be quite inert. During the initial stages of the steam oxidation of WSi2films deposited on SiO2, removal of Si from the silicide (to form SiO2) apparently leads to the formation of free W, rather than the anticipated tungsten‐rich W3Si3.

ISSN:0003-6951    

DOI:10.1063/1.90151

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Growth terraces on the surface of GaAs liquid phase epitaxial layers leave behind traces of increased doping concentration in the interior of the layer. These traces have been observed on (110) cleavage planes perpendicular to the (100) surface. Spatially resolved photoluminescence, cathodoluminescence, and photoetching have been applied to reveal the traces of the terraces. A fine structure on the photoetched cleavage plane indicates that the increase of thickness of the layer is caused in part by lateral growth of fine terraces traveling across the treads of the high terraces.

ISSN:0003-6951    

DOI:10.1063/1.90152

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Secondary ion mass spectroscopy (SIMS) has been used to measure the diffusion of deuterium in hydrogenated amorphous silicon. For a film deposited in a dc glow discharge in SiH4at a substrate temperature of 315 °C, the diffusion data fitsD(T) =1.17×10−2 exp(−1.53 eV/kT) cm2/s. This result implies that degradation of these films due to hydrogen out‐diffusion at 100 °C will not be significant until after more than 104years.

ISSN:0003-6951    

DOI:10.1063/1.90153

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Interfacial reactions between vanadium and thermally grown SiO2films have been studied with Xe ions implanted in the SiO2as diffusion markers. After the sample is heated at temperatures from 700 to 900 °C, the SiO2decomposes and V3Si forms. A backscattering analysis of the marker displacement discloses that vanadium is the dominant moving species which diffuses through the V3Si to react with the SiO2, whereas the oxygen atoms generated as a result of the reaction outdiffuse and oxidize the outer vanadium layer. For a clear presentation of the reaction and marker motion, the usual energy spectra of backscattering have been converted to in‐depth compositional profiles.

ISSN:0003-6951    

DOI:10.1063/1.90154

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

We have monitored the change in work function during the initial oxidation of discharge‐produced amorphous Si(H) and correlated this change with the amount of adsorbed oxygen as measured by Auger spectroscopy. With exposure to oxygen, the work function first increases (explained in terms of a dipole layer on the surface) and then decreases (explained in terms of penetration of oxygen below the surface). The explanation appears to be confirmed by similar measurements on the three primary crystallographic faces of single‐crystal Si. Initial sticking coefficient and dipole strength of oxygen adsorbed on amorphous Si are given.

ISSN:0003-6951    

DOI:10.1063/1.90155

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

MIS capacitors have been developed on a GaAs (n) substrate, the insulation being a thin layer of polymethylsiloxane (a few thousand angstroms thick). The present aim is to find out whether this process can provide an answer for the passivation of compound‐semiconductor components. The thin layer is deposited on the gallium arsenide substrate. It is obtained by glow discharge in a hexamethyldisiloxane vapor at ambient temperature. TheC‐Vcurves enable the polymer‐semiconductor interface properties to be determined, and in particular the calculation of fixed charges contained in the polymer (QT) and the surface‐state density (Nss).

ISSN:0003-6951    

DOI:10.1063/1.90156

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Measurements of the transverse differential conductivity of hot carriers in semiconductors are performed, for the first time, using an experimental setup described in the present paper. This allows the determination of the transverse diffusion coefficients.

ISSN:0003-6951    

DOI:10.1063/1.90157

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Thin undoped layers of GaAs grown directly on GaAs semi‐insulating substrates via liquid phase epitaxy (LPE) are shown to exhibit excellent buffering characteristics. Interfacial drift mobilities are shown to be much higher for the multilayer structures employing the thin buffer layer as compared with single‐layer structures. GaAs metal semiconductor field‐effect transistors (MESFET) fabricated on these LPE multilayer structures are shown to exhibit excellent rf characteristics. Best results include a noise figure of 1.87 dB with an associated gain of 10.6 dB at 12 GHz and a noise figure of 2.4 dB with an associated gain of 6.3 dB at 18 GHz.

ISSN:0003-6951    

DOI:10.1063/1.90158

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Dislocation glide and climb during optical excitation of GaAs laser material have been studied. A dislocation which has been induced to glide under high excitation can be induced to climb by reducing the incident excitation. The climb proceeds in a distinctly different crystallographic direction to, and at a rate which is five or six orders of magnitude slower than, the glide. Furthermore, only the threading portion of the dislocation experiences climb, a misfit dislocation excited at the same external intensity for the same time undergoes no discernible growth. Transmission electron microscopy examination of the climb region shows that it consists of a highly convoluted giant dislocation dipole. The nature of this giant dipole has been determined by a calibrated technique and it has been shown to grow by vacancy climb. Small coherent precipitate particles have been identified for the first time in the neighborhood of the giant dipole.

ISSN:0003-6951    

DOI:10.1063/1.90159

出版商:AIP    

年代:1978

数据来源: AIP