摘要:

Light‐emitting diodes have been fabricated in GaAs grown by metalorganic chemical vapor deposition on vapor‐deposited epitaxial Ge films on Si substrates. The light‐emitting junction was formed by zinc diffusion into then‐type GaAs layer. Room‐temperature light emission centered at 872 nm has been observed.

ISSN:0003-6951    

DOI:10.1063/1.94613

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

X‐ray photoelectron spectroscopy has been used to study the composition of 100‐A˚ thermally grown SiO2films that have been thermally nitrided in ammonia. The SiOxNy/Si interface was studied both by chemical depth profiling of the oxynitride and by removal of the Si substrate with XeF2. It is found that N is distributed throughout the film, but with the concentration higher at the surface and in a region centered 25 A˚ from the film/substrate interface. The interface region itself is found to be oxygen‐rich relative to the rest of the film. Possible models which can explain these results are discussed.

ISSN:0003-6951    

DOI:10.1063/1.94614

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The mechanism of Zn diffusion in a GaAs‐AlAs superlattice has been studied by measuring the x‐ray satellite intensity. The satellite intensity decreases and its width increases with increasng annealing time. The local structure around Zn atom is discussed.

ISSN:0003-6951    

DOI:10.1063/1.94615

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

X‐ray‐induced grafting of acrylic acid to poly (methyl methacrylate) (PMMA) increases the resist sensitivity by at least three orders of magnitude. Scanning electron microscopy of grafted PMMA revealed micron and submicron features for dose levels as small as 0.1–1 mJ/cm2, thus demonstrating the possibility of using this technique for x‐ray lithography.

ISSN:0003-6951    

DOI:10.1063/1.94616

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

A chemical etching process to obtain a double heterostructure of InP‐GaInAsP‐InP with a very narrow active layer width is proposed in which three layers are etched preferentially. The quaternary layer works as the inner etching mask; the cladding layers above and below the active layer show reversed‐mesa and normal‐mesa shapes, respectively. The method is used to fabricate a buried heterostructure laser which lases at 1.3 &mgr;m on thep‐type InP substrate. The fundamental lateral mode operation with threshold current as low as 15 mA is achieved with 0.8‐&mgr;m active layer width.

ISSN:0003-6951    

DOI:10.1063/1.94617

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

In recent publications, a large enhancement of the third order nonlinear optical susceptibility was predicted for GaAs–GaAlAs superlattices, as a result of the band nonparabolicities introduced by the additional periodicity of the superlattice. These predictions, based on the tight binding model, are here extended to the more realistic Kronig–Penney model. Results show that corrections to tight binding are non‐negligible; however, enhancements of &khgr;(3)are still large, but reduced by approximately 30%–50% over previous estimates.

ISSN:0003-6951    

DOI:10.1063/1.94618

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The application of photoconductors to fast rise time, high‐power switching is discussed. We report the successful switching of a 100‐kV system to generate a 1.8‐kA, <5‐ns rise time, 200‐ns duration electrical pulse in a 25‐&OHgr; load using a single photoconductor switch excited by aQ‐switched Nd: glass laser. The photoconductor was a 2.5‐cm‐long bar of single‐crystal, high‐resistivity silicon with a 0.5×0.5 cm cross section. Only a depth of about 1 mm of one side was used for conduction.

ISSN:0003-6951    

DOI:10.1063/1.94619

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

We have made the first measurements of the minority‐carrier diffusion lengthsL∥andL⊥respectively in bothn‐ andp‐ type GaP/GaAsxP1−x⟨100⟩ strained‐layer superlattices (SLS’s) in directions parallel and perpendicular to the interfaces. Using room‐temperature optical techniques, we find thatL⊥≊0.1 &mgr;m, which is more than an order of magnitude smaller thanL∥≊1.5 &mgr;m. The latter is comparable to that measured in the bulk materials which comprise the SLS layers, while the former demonstrates the existence of large potential barriers in both the conduction and valence bands.

ISSN:0003-6951    

DOI:10.1063/1.94620

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Disilane (Si2H6) is presented as a new silicon doping source in the metalorganic chemical vapor deposition of GaAs together with comparison results obtained using the conventional silane (SiH4) doping source. The doping characteristics of disilane were studied over a wide range of growth conditions: temperature, gas phase stoichiometry, and disilane concentration in the growth ambient. Silicon incorporation by means of disilane pyrolysis showed no temperature dependence, in sharp contrast to the strong temperature activated dependence found when employing silane. The decomposition reaction of disilane proved to be very efficient, reducing the amount of dopant gas required by about two orders of magnitude at the lower growth temperatures. Electrical measurements on disilane‐doped GaAs yield the same high mobilities as obtained in silane‐doped GaAs films, indicative of low compensation.

ISSN:0003-6951    

DOI:10.1063/1.94621

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

A modified form of deep level transient spectroscopy (DLTS) has been employed to perform energy‐resolved measurements of Si‐SiO2interface states. Decreasing the height of the trap filling pulse from the order of volts, as in the usual DLTS procedure, to tens of millivolts allows trap filling measurements to be made, rendering possible the use of Shockley–Read–Hall theory to show that the degeneracy factor of interface states is around unity. The energy dependence of the capture cross section in the upper band gap is also calculated from Shockley–Read–Hall theory and is contrasted for oxidation ambients with and without added HCl.

ISSN:0003-6951    

DOI:10.1063/1.94622

出版商:AIP    

年代:1984

数据来源: AIP