摘要:

We report optoelectronic cross‐correlation measurements of the response of photoconductor pulsers and sampling gates formed on Si wafers. These photoconductors were fabricated with standard integrated circuit fabrication techniques followed by shadow‐masked ion beam irradiation. Successful ion beam irradiations were performed with 2 MeV2H, 6 MeV He, and 30 MeV O with doses of 1015ion/cm2. Deep damage was necessary to eliminate long‐lived background currents in the cross correlations. Carrier lifetimes of 96, 47, and 29 ps were observed in photoconductors with carrier mobilities of ∼250 cm2/Vs.

ISSN:0003-6951    

DOI:10.1063/1.95236

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

A multiple‐stripe quantum well heterostructure laser diode operated in an external grating cavity is shown to exhibit the far‐field radiation patterns of the ‘‘supermode’’ eigenstates predicted by coupled mode analysis. Data (∼7330 A˚) are presented on a gain‐guided laser array at various continuous (cw, 300 K) operating currents to illustrate the progression of the supermodes from double‐lobed patterns (phase shift between emitters) to a single‐lobed pattern (no phase shift between emitters). As the cavity wavelength is scanned a cyclical progression (2.8‐A˚ period) of far‐field patterns (supermodes) is observed.

ISSN:0003-6951    

DOI:10.1063/1.95237

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Deep level transient spectroscopy measurements have been performed onpnjucntions in a strained‐layer superlattice (SLS) wafer composed of 240‐A˚‐thick alternating layers of GaP and GaAs0.3P0.7grown by metalorganic chemical vapor deposition. Comparison of these results with data taken on a standard alloy buffer layer of nearly the same average composition (18% As) reveals that in the SLS there are fewer types of traps, the trap concentrations are usually lower, the sample to sample variations across the wafer are much less, and the trap depth profiles are more uniform. Consequently, this comparison suggests that the SLS material is of better quality than the buffer which is mismatched to the underlying GaP substrate.

ISSN:0003-6951    

DOI:10.1063/1.95238

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Structures as small as 20 nm have been fabricated in GaAs by high‐resolution electron beam lithography and reactive ion etching. NiCr patterns were formed on the semiconductor surface by liftoff of a single‐layer electron beam resist. This metal mask pattern was transferred into the III‐V material by etching in a SiCl4plasma

ISSN:0003-6951    

DOI:10.1063/1.95239

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Behavior of longitudinal modes in a separately pumped, multiple twisted double‐heterostructure laser is investigated. A single longitudinal mode operation is observed in the current range up to 1.3Ithunder uniform pumping. The lasing wavelength is locked to a single longitudinal mode over a temperature range of 12 °C under uniform pumping. A continuous tuning range of 3.3 A˚ is obtained in one longitudinal mode. The wavelength shifts at a rate of 0.07 A˚/mA in the continuous tuning range.

ISSN:0003-6951    

DOI:10.1063/1.95240

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

We have studied the contact resistance in a metallization system that employs a direct contact between a tungsten–titanium alloy and shallow junctions in silicon. The values obtained in the present study are all within acceptable limits (<100 &OHgr; &mgr;m2) for very large scale integration applications. The metal–silicon system has been subjected to moderate heat treatments, similar to those required in processing two‐level metallization schemes. No detrimental effects on the electrical properties of these contacts have been observed.

ISSN:0003-6951    

DOI:10.1063/1.95241

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The diffusion of ion‐implanted phosphorus in silicon during rapid thermal annealing has been studied. Depending on the implant dose, we find two distinct kinds of diffusion behavior. For low dose (1×1014cm−2) P+‐implanted Si, a profile redistribution is observed which becomes observable at 900 °C for annealing times of 10 s, but which is temperature independent in the range 800–1150 °C. This initial redistribution is much more rapid than conventional diffusion coefficient data would predict. For high dose (2×1015cm−2) P+implanted and short time (10 s) annealed Si, the dopant profile broadening is strongly temperature dependent. The experimental profiles are in this case in agreement with concentration enhanced diffusion profiles.

ISSN:0003-6951    

DOI:10.1063/1.95242

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Silicon surfaces which had been exposed to a CF4/H2plasma have been characterized by x‐ray photoelectron spectroscopy, ellipsometry, He ion channeling, and H profiling techniques. Plasma exposure leads to the deposition of a thin (∼30 A˚ thick) C,F‐polymeric layer. Hydrogen and/or damage (displaced Si atoms) can be detected in the near‐surface region up to a depth in excess of 400 A˚ from the Si surface.

ISSN:0003-6951    

DOI:10.1063/1.95243

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

We report the first experimental observation of a semiconductor/liquid junction whose open circuit voltageVocis controlled by bulk diffusion/recombination processes. Variation in temperature, minority‐carrier diffusion length, and/or in majority‐carrier concentration produces changes in theVocof then‐Si/CH3OH interface in accord with bulk recombination/diffusion theory. Under AM2 irradiation conditions, the extrapolated intercept at 0 K ofVocvsTplots yields activation energies for the dominant recombination process of 1.1–1.2 eV, in accord with the 1.12‐eV band gap of Si. A crucial factor in achieving optimum performance of then‐Si/CH3OH interface is assigned to photoelectrochemical oxide formation, which passivates surface recombination sites at then‐Si/CH3OH interface and minimizes deleterious effects of pinning of the Fermi level at the Si/CH3OH junction. Controlled Si oxide growth, combined with optimization of bulk crystal parameters in accord with diffusion theory, is found to yield improved photoelectrode output parameters, with 12.0±1.5% AM2 efficiencies and AM1Vocvalues of 632–640 mV for 0.2‐&OHgr; cm Si materials.

ISSN:0003-6951    

DOI:10.1063/1.95244

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Silicon crystals are implanted with nitrogen in the dose range of 1010–1016ions/cm2. After thermal annealing at 700 °C photoluminescence at 1.1223 eV (Aline) is observed which was reported previously only from bulk doped crystals. The dependence on the implantation dose and the annealing behavior of the recombination center are investigated in detail. We find that electrically active nitrogen is not responsible for the formation of the defect whereas there exists a correlation with vacancy‐interstitial nitrogen complexes.

ISSN:0003-6951    

DOI:10.1063/1.95245

出版商:AIP    

年代:1984

数据来源: AIP