摘要:

Photothermal ionization spectroscopy is employed to monitor the residual donor impurities in InP grown by vapor phase epitaxy, and study the effect of adding O2to the carrier gas. The dominant donor species are found to be Si and S, irrespective of the O2addition, and their concentrations are obtained with the aid of Hall measurements. The result shows that the O2addition reduces the incorporation of Si into InP but does not affect the incorporation of S.

ISSN:0003-6951    

DOI:10.1063/1.97856

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

GaAs1−xSbxnearly lattice matched to InP substrates has been grown by molecular beam epitaxy. For a given As and Sb flux, the GaSb mole fraction is shown to be sensitive to the Ga flux rate. Low‐temperature photoluminescence spectra exhibit a dominant emission line at 0.780–0.790 eV with a full width at half‐maximum as narrow as 7.6 meV, which is believed to be the narrowest obtained to date. Optical absorption measurements demonstrate that the band gap of this material is considerably smaller than predicted by the commonly accepted composition/band gap relation.

ISSN:0003-6951    

DOI:10.1063/1.97857

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

The first hydrogenated amorphous germanium and hydrogenated amorphous silicon‐germanium alloy field‐effect transistors with appreciable field‐effect response inn‐ andp‐channel modes were developed by reducing the dihydride content in the films. Field‐effect mobilities were derived from transistor characteristics. Hole mobilities are superior to those in pure hydrogenated amorphous silicon which offers the opportunity for improved thin‐film devices.

ISSN:0003-6951    

DOI:10.1063/1.97858

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

A selectively doped,n‐type, single strained quantum well (SSQW) structure, consisting of an 8‐nm‐thick In0.25Ga0.75As layer sandwiched between thick GaAs layers, has been grown by molecular beam epitaxy. Low‐field Hall‐effect measurements from 4 to 300 K and field‐dependent magnetotransport measurements at 4 K show that conduction through the doped GaAs layers competes with conduction from the two‐dimensional electron gas confined by the InGaAs quantum well. Photoluminescence measurements at 4 K yield a band‐gap energy of 1.30 eV and confirm the transport measurement of carrier density in the InGaAs conducting channel. Analysis of the parallel‐conduction process yields channel carrier density and mobility which are consistent with data on strained‐layer superlattices (SLS’s) not exhibiting parallel conduction. Comparison of the SSQW and SLS results demonstrates that heavily doped SSQW structures require narrow doping spikes to avoid parasitic current paths.

ISSN:0003-6951    

DOI:10.1063/1.97859

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

The critical resolved shear stress of GaAs single crystals doped with silicon was directly measured using dynamical compression tests at high temperatures. At the melting point the critical resolved shear stress is 0.032 and 0.027 kg/mm2for crystals doped with 1.5×1018and 3×1018cm−3silicon, respectively. These values are lower than that for undoped GaAs. This reinforces our earlier conclusion that solid solution hardening and the reduction of crystallographic glide is not the only mechanism by which dopants reduce the formation of dislocations during the growth of single crystals from the melt.

ISSN:0003-6951    

DOI:10.1063/1.97860

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

We report the observation of reflection high‐energy diffraction (RHEED) intensity oscillations during the growth of GaAs using triethylgallium in chemical beam epitaxy (CBE). The oscillation period corresponds exactly to the time required for the growth of one monolayer. RHEED oscillation studies also suggest the absence of flux transients due to switching of gas flows, abrupt and complete initiation and termination of growth with submonolayer resolution, and that CBE is capable of thickness control with submonolayer precision when coupled with the use ofinsituRHEED intensity monitoring technique. The temperature and flux dependence of growth rates are also studied using RHEED oscillations. Results indicate that CBE growth is predominantly via a two‐dimensional layer‐by‐layer mechanism.

ISSN:0003-6951    

DOI:10.1063/1.97861

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Soft x‐ray photoemission measurements of ultrahigh‐vacuum‐cleaved GaP (110) surfaces with In, Al, Ge, Cu, and Au overlayers reveal Fermi level stabilization over a wide energy range and a near‐ideal correlation between Schottky barrier height and metal work function. Coupled with recent findings for InAs (110) and InxGa1−xAs (100) (x>0) surfaces, these results demonstrate that Fermi level pinning in a narrow energy range is not representative of metal/III‐V compound semiconductor interfaces.

ISSN:0003-6951    

DOI:10.1063/1.97862

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Rapid thermal annealing has been used to study the activation mechanism of zinc ions implanted into GaAs. The data divide into two parts, a time‐dependent and a time‐independent regime. Analysis of these regimes suggests that inactive zinc becomes electrically active by local diffusion to an unoccupied gallium vacancy, the energy for this process being 1.1 eV. The time‐independent regime produces another energy of 0.37 eV which is suggested to be the energy required to place a zinc atom onto a gallium vacancy.

ISSN:0003-6951    

DOI:10.1063/1.97863

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

In this work, a deep level transient spectroscopy (DLTS) study onn‐type epitaxial cubic silicon carbide grown on Si substrates has been performed. The results of this study indicate the presence of at least two majority‐carrier traps. One trap (SCE1) is located 0.34 eV from the conduction‐band edge; the other trap (SCE2) is located 0.68 eV from the conduction‐band edge. These two traps have concentrations of approximately 1×1015cm−3. The DLTS spectrum as a function of the surface treatment of the SiC has been investigated. The results of this investigation indicate that one of the levels (SCE2) appears to be formed as a result of high‐temperature thermal oxidation.

ISSN:0003-6951    

DOI:10.1063/1.97864

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

We have developed a novel thermal precracking technique which has improved the electrical quality of GaAs grown using trimethylarsenic, while maintaining excellent surface morphology. Background doping is reduced by a factor of 5, and carbon incorporation is reduced by a factor of 10 or more. This method may prove useful for reducing carbon incorporation from other organometallic arsenic sources as well. Net background doping below 1016cm−3and room‐temperature electron mobilities of 4000–4500 cm2/V s have been obtained. These are the best values reported for GaAs grown using trimethylarsenic.

ISSN:0003-6951    

DOI:10.1063/1.97865

出版商:AIP    

年代:1987

数据来源: AIP