摘要:

The surface barrier heights &fgr;bnand room‐temperature band gapsEgof Si‐doped InxAl1−xAs layers grown by molecular beam epitaxy onn‐type (100) oriented InP substrates have been determined as a function of composition with capacitance versus voltage, internal photoemission, photoluminescence, and double‐crystal x‐ray rocking curve measurements for 0.45<x<0.55. The results indicate thatEgand &fgr;bnare linear functions ofx; they also suggest that &fgr;bn(0.78)=0 and, forx>0.78,n‐type surfaces might be accumulated andp‐type surfaces are likely to be inverted.

ISSN:0003-6951    

DOI:10.1063/1.97290

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Time‐resolved emission spectra of ZnS:TbF thin films in photoluminescence and electroluminescence were measured and compared within a relatively short delay. It was concluded that the excitation mechanism of the Tb center involves energy transfer from the ZnS host in which the Tb‐related center acts as an efficient energy source for the excitation of the 4f8electronic system in the Tb3+ions. In addition to the ZnS:TbF thin film, a similar excitation mechanism was found to exist in the ZnS:Mn thin film. It is proposed that the TbF complex center and Mn act as an isoelectronic center or deep electron trap in ZnS thin films.

ISSN:0003-6951    

DOI:10.1063/1.97291

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Stoichiometry dependences of the electrical activation efficiency in Si implanted layers have been investigated for undoped, semi‐insulating (SI) liquid encapsulated Czochralski (LEC) GaAs grown from melts of different compositions. The absolute value of lattice parameter was used as a measure for deviation from stoichiometry in GaAs. Irrespective of the annealing procedures, the electrical activation efficiency tends to increase and saturate to a maximum value as the crystals become As‐rich, i.e., the lattice parameter increases from 0.565358 to 0.565364 nm. These results demonstrate that the precise control of stoichiometry greatly improves the reproducibility of LEC growth of undoped SI GaAs suitable for GaAs integrated circuits.

ISSN:0003-6951    

DOI:10.1063/1.97292

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Double heterostructure planar waveguides with an InGaAs/InP multiple quantum well (MQW) core and InP cladding layers were grown by atmospheric pressure metalorganic chemical vapor deposition. Ridge waveguides had a low propagation loss of 0.8 dB/cm for 1.52 &mgr;m input light. The indices of refraction for the guided TE and TM modes have been measured and the bulk dispersion curves of the MQW material for the 1.46–1.55 &mgr;m wavelength region were derived.

ISSN:0003-6951    

DOI:10.1063/1.97293

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The oxidation in air of substoichiometric films of SiOxby scanned, cw laser irradiation at 500 nm has been studied as a function of incident power density up to a maximum of 5.3 MW/cm2. Results obtained on substrates having widely different thermal conductivities suggest that the oxidation is thermally stimulated. Observed Auger electron spectra and measured refractive indices in oxidized films are characteristic of amorphous SiO2.

ISSN:0003-6951    

DOI:10.1063/1.97294

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Experiments are reported on the lateral photoeffect in a novel type of amorphous superlattice consisting of 6 A˚ of Ti and 13 A˚ of Si grown on Si substrate. The spectral, temperature, bias voltage, and time dependences have been measured for this new position sensitive detector.

ISSN:0003-6951    

DOI:10.1063/1.97295

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The interactions between thin Ge overlayers and both cleaved and ion‐sputtered Hg1−xCdxTe surfaces have been examined using synchrotron radiation. Ge forms an unreactive layer on cleaved substrates ofx=0.21 andx=0.28 with only a small loss of Hg (∼20%) from the interface. In contrast, deposition of Ge onto sputtered substrates results in approximately two (x=0.21 material) or three (x=0.28 material) times the Hg loss relative to the clean surface. The difference in behavior of the sputtered and cleaved material is due to sputter‐induced defects at the surface. The increased loss of Hg from the sputteredx=0.28 material is a result of a greater number of these defects caused by the weaker Hg–Te bonding and the corresponding increase in the preferential sputtering of Hg from the surface. No difference was observed between sputteredp‐type andn‐type material. These results are a consequence of GeTe and HgTe having very similar heats of formation; as such, deposition of Ge provides an indication of the reactivity of (HgCd)Te surfaces.

ISSN:0003-6951    

DOI:10.1063/1.97296

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

AlGaAs‐GaAs heterofacep+‐p‐nsolar cells have been fabricated directly on Si substrates using metalorganic chemical vapor deposition. GaAs on Si solar cell efficiency as high as exceeding 14.5% at AM1.5 was obtained by cleaning the substrate surface and repeating GaAs film growth interruption. This value is the highest ever reported for GaAs solar cells on Si substrates. Defects, which could not be observed in homoepitaxially grown GaAs film, were observed in the heteroepitaxial GaAs films through electron beam induced current image. Relatively low conversion efficiency of the GaAs cell on Si compared to the GaAs can be attributed to these defects.

ISSN:0003-6951    

DOI:10.1063/1.97245

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Silicon samples subjected to a CF4reactive ion etch exhibit theG‐line luminescence known from photoluminescence studies of irradiation damage in Si. We investigate the mechanism of low‐energy carbon implantation by CF4plasma and find a linear dependence of theG‐line luminescence intensity on the substitutional carbon concentration in the samples. By a standardized etching and photoluminescence procedure, we expect to determine carbon concentrations two orders of magnitude smaller than the ASTM infrared absorption method.

ISSN:0003-6951    

DOI:10.1063/1.97246

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Electron spin resonance spectra obtained on polycrystalline silicon produced by annealing of chemical vapor deposition silicon are investigated before and after plasma hydrogenation of the material. Before hydrogenation, two paramagnetic defects are observed, one of them remaining unidentified (g=2.0084). Hydrogenation decreases the total spin density, but the two defects are affected differently; the defect withg=2.0084 is more efficiently passivated. The results are discussed in terms of the inter‐ and intragranular nature of the paramagnetic defects and of hydrogen diffusivity in the polycrystal.

ISSN:0003-6951    

DOI:10.1063/1.97247

出版商:AIP    

年代:1986

数据来源: AIP