bluuebunny/crossref_metadata_2025_split huggingface dataset:
Doped Channel MBE GaAs Field Effect Transistor (MEDFET) with Laser Processed Ohmic Contacts
Authors: Halkias G. , Hatzopoulos Z. , Christou A. 
Published: March 2011

ABSTRACTA doped channel heterojunction Field Effect Transistor (Metal-Doped Channel Field Effect Transistor, MEDFET) was fabricated using a molecular beam epitaxially (MBE) grown structure and excimer laser processed TiW-silicide ohmic contacts and TIW-Si gate metallization. The device was characterized at X-band frequencies in order to investigate the potential benefits of the semiconductor MBE structure and the potential stability of the laser processed TiW/Si electrode metallizations.
A Recessed-Gate In0.52Al0.48As/n+-In0.53Ga0.47As Misfet
Authors: Alamo Jesús A. del , Mizutani Takashi 
Published: March 2011

ABSTRACTScaling of the In0.52Al0.48As insulator thickness of In0.52Al0.48As/n+-In0.53Ga0.47As MIStype FET's is experimentally found to result in a drastic drop of performance below 200 Å. This is demonstrated to arise from an increase in the sheet resistance of the extrinsic portions of the device that accompanies insulator scaling. In order to solve this problem, a recessed-gate dopedchannel MISFET with a very thin (300 Å) n+-In0.53Ga0.47As cap layer has been fabricated. A 1.5 μm long gate device showed a transconductance of 285 mS/mm and a current-gain cut-off frequency of 19.4 GHz. This result proves the ability of a thin n+-In0.53Ga0.47As cap to reduce source resistance and improve device performance. The fabricated recessed-gate structure is a promising candidate for high-performance scaled MIS-type FET's based on thin, heavily-doped In0.53Gav0.47 As channels.
Heavily-Doped n+-GaAs with Low Compensation Grown by Atmospheric OMVPE
Authors: Venkatasubramanian R. , Ghandhi S. K. 
Published: March 2011

ABSTRACTAtmospheric OMVPE has been used, with SiH4 as the dopant, to grow n+-GaAs with free-carrier levels upto about 9e18 cm−3. Following a steady rise in carrier concentration with dopant pressure, the carrier concentration is seen to fall rapidly with further doping. Hall-effect and quantitative SIMS data have been used to obtain the distribution of silicon onto donor and acceptor sites. It is seen that there is negligible compensation upto free-carrier levels of about 5e18 cm−3. The mechanism of compensation throughout the doping range is discussed.
Fabrication of III-V Semiconductor Quantum Dots in Porous Glass.
Authors: Luong John C. , Borrelli Nicholas F. 
Published: March 2011

ABSTRACTSpatially quantized systems of III–V compounds have, in recent years, attracted considerable theoretical interest. However, the fabrication of quantum dots, a three-dimensionally quantum-confined microstructure, is particularly cumbersome and requires sophisticated lateral patterning techniques. A method, reported recently, which utilizes the microporosity of Vycor brand porous glass to produce quantum-confined microcrystals of II–VI and IV–VI semiconductors, is now extended to the fabrication of III–V quantum dots, by incorporating a microwave plasma assisted MOCVD technique. In this process, organometallic precursors impregnated in porous glass can be effectively cracked to deposit III–V microcrystals in glass. The results are discussed in light of the quantum size effect manifested by the optical absorption and photoluminescence data.
Incorporation and Diffusion of P-Type Dopants for Metal Organic Vapor Phase Epitaxy
Authors: Tischler M. A. , Kuech T. F. 
Published: March 2011

ABSTRACTThe control of p-type dopants is very important in producing high performance minority carrier devices such as heterojunction bipolar transistors (HBT) and lasers. In this study, an electrical characterization technique is described which is very sensitive to the p-type dopant profile in a heterojunction. Both the placement of the dopant, i.e. the as-grown profile, and thermal diffusion effects have been investigated. The factors which control the initial placement and subsequent diffusion of the dopant species have been determined and used to produce device-quality GaAs/Al0.30Ga0.70As p+/n heterojunctions.
Electron Irradiation Doping with Carbon in Chemical Beam Epitaxy
Authors: Iimura Y. , Nagata K. , Den S. , Aoyagi Y. , Namba S. 
Published: March 2011

ABSTRACTDissociation species produced by low-energy electron Irradiation of triethylgallium (TEGa) have been used as a carbon doping source during growth of GaAs by chemical beam epitaxy. Mass spectral analysis shows that TEGa dissociates at electron energies greater than 20 eV, and that the fragmentation pattern of TEGa consists of methyl radicals, ethyl radicals, and gallium compounds. In order to study the doping properties of carbon, carbon-doped GaAs films were grown under several conditions and were characterized by Hall measurements, photoluminecence spectrum, secondary Ion mass spectrometry, and double crystal X-ray diffraction. The hole carrier concentration could be varied up to ∼1020 cm−3, and the doping profile of carbon was well-controlled.
Electrical and Optical Properties of Vanadium in Omvpe-Grown GaAs
Authors: Hobson W. S. , Pearton S. J. , Swaminathan V. , Jordan A. S. , Kao Y. J. , Haegel N. Mk , Kanber H. 
Published: March 2011

AbstractThe electrical and photoluminescent properties of vanadium incorporated into GaAs epitaxial layers from a VO(OC2 H5)3 source during organometallic vapor phase epitaxy were examined. The vanadium concentration in the GaAs was controllably varied from 1016 to 1018 atoms cm−3. Deep level transient spectroscopy showed the presence of an electron trap at Ec – 0.15 eV which increased in concentration with vanadium content of the epitaxial layers. A maximum value of 8 × 1015 cm−3 for this trap was obtained. There were no midgap electron traps associated with vanadium. In intentionally Si-doped epitaxial layers, co-doping with vanadium was observed to have no effect in reducing the carrier density when the Si concentration was > 4 × 1016 cm−3. The net carrier concentration profiles resulting from 29 si implantation into GaAs containing 1018 cm−3of total V had sharper tails than for similar implantation into undoped material, indicating the presence of less than 1016 cm−3V-related acceptors. Photoluminescent spectra exhibited the characteristic V+3intracenter emission at 0.65∼0.75 eV. No other deep level photoluminescence was detected. For a V concentration of 1016 cm−3only 2.5 × 1013 cm−3was electrically active. Over the entire V concentration investigated this impurity was predominantly (≥99%) inactive.
Atomic Layer Epitaxy: modeling Of Growth Parameters for Device Quality GaAs.
Authors: Colas E. , Bhat R. , Nihous G. C. 
Published: March 2011

AbstractDevice quality GaAs was grown in a conventional Organometallic Chemical Vapor Deposition (OMCVD) reactor, using sequential group III and V reactant gas exposures typical of Atomic Layer Epitaxy (ALE). The importance of gas phase concentration transients during the ALE cycles was revealed by systematic investigations of the effect of the sequences used, for the cycles, on impurity incorporation as well as on the growth rates. In this study, we attempt to quantify the effects of such transients by solving the diffusion equation for the reactant gases, with initial conditions specific to ALE. We used this model to calculate the time dependence of the reactant gas concentration at the growing surface. This quantitative study gives us new insights into the ALE technique and confirms that the V/II ratio at the substrate surface can be controlled by the choice of the gas sequence.
Reduction of Toxic Gas Emissions During Gas Cabinet Manifold Vent Purge Cycles Using a Novel Scrubbing Material.
Authors: Luxon Bruce A. , Vaughan V. R , Mcmanus J. V. , Tom G. M. 
Published: March 2011

AbstractThe rapid growth of the microelectronics industry has spawned environmental problems associated with the process gases used to prepare semiconductors. Historically, many of these problems have been ignored because relatively low volumes of gases are associated with semiconductor fabrication; however, the exceptionally high toxicity of these materials (e.g. arsine, phosphine, silane, etc.) can cause major problems, especially for small quantity hazardous waste generators. Large commercial users have built expensive facilities for handling these materials, but small quantity generators typically have vented to the atmosphere through their exhaust ductwork. This is particularly true during cylinder changes where the gas manifold is repeatedly purged into the ductwork of the facility with no other treatment.A new family of novel vent gas scrubbers that will cost-effectively reduce toxic air emissions below the Threshold Limit Value (TLV) during cylinder changes is described. Called a vent gas scrubber (VGS), this device combines high capacity, high selectivity and very high capture-effectiveness. These properties permit the VGS to be extremely compact (ca. 125 ml), last a long time in use (several years or more) and to reduce emissions to well below the TLV for improved gas handling safety.
Automation Features Used with the Halide-Cvd Technique at the AT&T-Microelectronics Production Plant in Reading, Pennsylvania
Authors: Rhoades Bruce J. , Travis Steven J. , Sands David G. 
Published: March 2011

AbstractThe the Halide-CVD technique is used in both research and development as well as production at AT&T. The unique requirements of the production environment dictate that reactor designs include features to improve reproducibility and maintenance, as well as reduce operator intervention. Features incorporated in the Halide-CVD reactor at AT&T include microprocessor control of valves, mass flow controllers, and furnace temperature setpoints. The unique needs of a production facility, such as process reproducibility, and commonality with standard plant equipment and information systems, will be highlighted.
Heteroep1Taxial Nucleation and Structural Properties of MBE GaAs on Recessed Si: Etching Implications.
Authors: Boeck Jo De , Liang Jiben , Vanhellemont Jan , Deneffe Kristin , Hoof Chris Van , Arent Douglas J. , Borghs Gustaaf , Christen Jürgen 
Published: March 2011

AbstractGaAs is grown embedded in pre-etched wells in the Si substrate. HNO3:HF, KOH:H2O and a dry etch technique are used as alternatives to form the wells. Cross-sectional SEM views of AlGaAs/GaAs heterostructures reveal the growth front and facet formation for the different sidewall geometries. Transmission electron microscopy is used to study epilayer degradation in relation to the substrate damage and the presence of edge induced defects in the GaAs. Cathodoluminescence reveals the uniformity of strain present in the GaAs layer embedded in the wet etched well. The impact of the different etching techniques on device integration is briefly discussed.
Electron Transport in InAs/AlSb Quantum Wells: Interface Sequencing Effects
Authors: Tuttle Gary , Kroemer Herbert , English John H. 
Published: March 2011

AbstractWe present data on electron transport in AlSb/InAs/AlSb quantum wells grown by molecular beam epitaxy. Because both anion and cation change across an InAs/Alsb interface, it is possible to grow such wells with two different types of interfaces, one with an InSb-like bond configuration, the other AlAs-like. Electron mobility and concentration were found to depend very strongly on the manner in which the quantum well's interfaces were grown, with high mobilities seen only if the bottom interface is InSb-like. An As-on-Al sites antisite defect model is postulated for bottom AlAs-like interfaces.
Photoluminescence and Plane-View Tem Studies of Epitaxial ZnSe Layers on GaAs After H2 Gas Heat-Treatment
Authors: Sekoguchi-pl Maki , Murase Takashi , Taguchi Tsunemasa 
Published: March 2011

AbstractLow-temperature photoluminescence and plane-view TEN observations have been carried out to investigate the strain and microstructural defects in MOCVD-grown ZnSe/(100)GaAs after post- growth annealing in H2gas at temperature between 350 and 500V. A 0.35 µm thick ZnSe epitaxial layer is originally under compres- sive strain, but after annealing this receives considerably tensile strain, and the neutral deep-acceptor bound exciton () line and the edge-emission band at about 2.72 eV newly appear. The observed changes are interpreted in terms of the energy down- shift of the excitonic lines and deviation from stoichiometry. The annealed film, which deteriorated as a result of generations of dislocation tangles and small loops, results in the strong deep-level emissions around 2.25 eV.
Structure of Highly Perfect Semiconductor Strained-Layer Superlattices: High-Resolution X-Ray Diffraction and Computer Simulation Studies
Authors: Vandenberg J. M. 
Published: March 2011

AbstractHigh-resolution x-ray diffraction (HRXRD) measurements of strained-layer superlattices (SLS's) have been carried out using a four-crystal monochromator. A wide asymmetric range of sharp higher-order x-ray satellite peaks is observed indicating well-defined periodic structures. Using a kinematical diffraction step model very good agreement between measured and simulated x-ray satellite patterns could be achieved. These results show that this x-ray method is a powerful tool to evaluate the crystal quality of SLS's.
X-Ray Interference Measurements of Ultrathin Semiconductor Layers
Authors: Wie C.R. 
Published: March 2011

AbstractWe present various x-ray diffraction phenomena from semiconductor hetero-epitaxial layers. Each of these phenomena gives useful information on the layers. Knowing what to look for in the x-ray rocking curve (XRC) can make this nondestructive technique a very powerful tool for characterization of a few A-several g.tm thick layers We discuss the use of individual Bragg peak, diffraction fringe, and interference structure to obtain layer information. We particularly emphasize the use of x-ray interference in studying buried strained quantum well or quantum barrier layers. We present experimental rocking curves of an AlGaAs/GaAs double heterojunction laser structure and GaInAs/GaAs strained layer superlattices in both <001> and <111> orientations.
Evaluation of Large Diameter InP Substrate Material
Authors: Trapp K. D. C. , Asom M. T. , Carver G. E. , Monberg E. M. , Thiel F. A. , Barns R. L. 
Published: March 2011

AbstractExpanding interest in large-scale fabrication of electronic and photonic devices and in the scale-up of epitoxial growth reactors is creating the need for high quality large diameter InP substrate material. This paper will discuss the evaluating of three-inch diameter semi-insulating Fe-doped InP substrate material purchased from two commercial suppliers. The results of Photon Back Scatter, Infrared Transmission Microscopy, Hall Effect, and Spatially Resolved Photoluminescence measurements will be presented and evaluated.
Trichloride-Hydride Vpe: A Hybrid Regrowth Process for III-V Epitaxial Heterostructures
Authors: Digiuseppe M. A. , Mattera V. D. , Brown J. , Marchut L. , Ekholm D. T. , Filipe J. , Buckley D. N. , Peticolas L. J. 
Published: March 2011

AbstractInP based alloy epitaxial heterostructures currently are being developed as light sources and detectors for optoelectronic applications. High performance requirements at very high frequency operation have resulted in the need for complex device structures which can require one or more epitaxial steps. As a result, hybrid growth techniques combining LPE with either hydride VPE, trichloride VPE or metal organic CVD previously have been used to grow emitter and photodetector heterostructures. In this paper, a hybrid trichloride-hydride VPE growth technique for complex heterostructures is described. Trichloride VPE which is particularly suited for certain regrowth applications because of its inherent in-situ etching capability has been successfully utilized to regrow low-doped, high purity InP on InP/InGaAs/InGaAsP heterostructures grown by hydride VPE. Transmission electron microscopy has shown that the regrowth interface is free of major defects and dislocations. P-diffused APD mesa devices obtained from these structures were operated with fields at the regrowth interface as high as 3.8 × 105V/cm. Primary dark currents were observed as low as 1.4nA.
Multistep, In-Situ Single Wafer Processing - Materials, Device and Equipment Issues
Authors: Hauser J. R. , Masnari N. A. , Littlejohn M. A. 
Published: March 2011

ABSTRACTMultistep, in-situ single wafer processing is being explored as an alternative processing approach to standard batch silicon wafer processing. Advantages and disadvantages of this approach are explored and an evaluation given of the potential for future advanced, low temperature wafer processing. Multistep, single wafer processing offers many advantages for advanced device and IC development but much technology research and equipment development is needed to achieve its potential.
Device Degrading Interactions between Silicide Films and Bulk Defects during Rapid Thermal Annealing
Authors: Sparks D.R. , Alvi N.S. 
Published: March 2011

ABSTRACTThe interaction between titanium and nickel silicide films with dislocations generated at the wafer edge by thermal stress is examined in this work. The local dislocation density of the silicon wafers varied from zero to 4.8×106cm across a slice. Both titanium and nickel were deposited as thin films in the contact regions of the p-n junction diodes. Wafers were rapid thermal annealed, sequentially, for 30 s at temperatures between 300°C and 700°C. Reverse bias leakage current measurements of the as-deposited and annealed wafers were used to evaluate the impact of silicides and bulk defects on devices. A significant increase in leakage current due to the silicide/defect interaction was observed above 600 °C for both titanium and nickel. Leakage currents of devices fabricated in regions of high bulk defect density increased with the anneal temperature and dislocation density.
Reaction Kinetics of Sputter-Deposited Ti On SiO2 Substrates during Rapid Thermal Annealing
Authors: Yun E.J. , Chun H.G. , Jung K. , Kwong D.L. , Lee S. 
Published: March 2011

ABSTRACTIn this paper, the interactions of sputter-deposited Ti on SiO2 substrates during rapid thermal annealing in nitrogen at 550°C - 900°C for 10 - 60 s have been systematically studied using X-ray diffraction, Auger electron spectroscopy, transmission electron diffraction, TEM & cross-sectional TEM, and sheet resistance measurements.
The Outdiffusion of Boron and Arsenic from Pre-Formed Ion-Beam-Mixed Cobalt Disilicide Layers using Rapid Thermal Processing
Authors: Moynagh P. B. , Brown A. A. , Rosser P. J. 
Published: March 2011

ABSTRACTArsenic out-diffusing from Cobalt Disilicide into underlying silicon displays an enhanced activation level of up to 80%, and an enhanced diffusivity of greater than one order of magnitude. Boron, in contrast, displays a diffusivity as small as 0.25 times that expected. These observations are consistent with a considerable Si-vacancy injection by the silicide layer into the underlying substrate.
A Study of the Morphology of Titanium Silicide Films and the Titanium Silicide-Silicon Interface
Authors: De Lanerolle N. , Moser L. , Hoffman D. , Ma D. , Sterner D. 
Published: March 2011

ABSTRACTThis paper is based on a detailed study of the effect of high temperature heat treatment in a nitrogen ambient on the titanium silicide film and the silicide-silicon interface. Our investigations showed that the two cannot be studied in isolation. This study involved observing the morphology of the silicide film after thermal treatment in a furnace at 925° C for 5, 30, 60 and 120 minutes. Part of each wafer was then stripped of silicide, thereby exposing the morphology of the interface of TiSi2 with Si. In this way, it was possible to correlate the changes on the surface with that of the interface. The samples were analyzed by scanning electron microscopy and energy dispersive spectroscopy. Evidence for the growth and evolution of Si islands were found as a result of this study. These islands appear to form preferentially at specific locations of the interface, namely at the meeting points of the grain boundaries of the silicide film with the interface. Even though the morphology of the silicide surface becomes more lumpy with increased annealing times, Si islands were not observed at the surface, contrary to what has been reported during vacuum annealing. It appears that the nitrogen ambient has a stabilizing influence in keeping the surface apparently stable. Associated with the increasing size of the islands was the simultaneous sinking of the TiSi2 into the Si substrate.
Single Wafer Rapid Thermal Multiprocessing
Authors: Saraswat Krishna C. , Moslehi Mehrdad M. , Grossman David D. , Wood Sam , Wright Peter , Booth Len 
Published: March 2011

ABSTRACTFuture success in microelectronics will demand rapid innovation, rapid product introduction and ability to react to a change in technological and business climate quickly. These technological advances in integrated electronics will require development of flexible manufacturing technology for VLSI systems. However, the current approach of establishing factories for mass manufacturing of chips at a cost of more than 200 million dollars is detrimental to flexible manufacturing. We propose concepts of a micro factory which may be characterized by more economical small scale production, higher flexibility to accommodate many products on several processes, and faster turnaround and learning. In-situ multiprocessing equipment where several process steps can be done in sequence may be a key ingredient in this approach. For this environment to be flexible, the equipment must have ability to change processing environment, requiring extensive in-situ measurements and real time control. In this paper we describe the development of a novel single wafer Rapid Thermal Multiprocessing (RTM) reactor for next generation flexible VLSI manufacturing. This reactor will combine lamp heating, remote microwave plasma and photo processing in a single cold-wall chamber, with applications for multilayer in-situ growth and deposition of dielectrics, semiconductors and metals.
Bistable Defects Induced in GaAs by H2 Plasma Process
Authors: Boddaert X. , Vuillaume D. , Stievenard D. , Bourgoin J.C. , Boher P. 
Published: March 2011

ABSTRACTWe have studied the effect of an H2 plasma (150 W; 150°C; 10, 20, 50, 100 s) on unannealed and annealed (850°C, AsH3 atmosphere) LEC GaAs material. Using Deep Level Transient Spectroscopy, we have shown that the plasma induces a main bistable defect DO, which has two possible stable states Dl and D2. A complete determination of the corresponding Configuration Coordinate Diagram has been done. Finally, no correlation has been obtained between DO and the native defects EL6, EL3 and EL2. No passivation of the EL2 defect has been observed and the evolution of the D0 concentration results from the association of hydrogen with AsGa. These observations are in disagreement with the identification of EL2 with an isolated AsGa.
Mo—In—Mn Based Ohmic Contact to P—GaAs
Authors: Kalkur T.S. , Lu Y.C. , Caracciolo Robert 
Published: March 2011

ABSTRACTMo—In—Mn metallization is used to form ohmic contact on Be—implanted Rapid Thermally annealed GaAs. The rapid thermal alloying of Mo—In—Mn contact metallization is performed at various temperatures and times in A.G. Associates Heat Pulse 410 system in forming gas atmosphere. The electrical properties of the contacts were analyzed by current-voltage and contact resistivity measurements. The microstructures of the contacts were analyzed using scanning electron microscope, energy dispersive x-ray analysis, x-ray diffraction and secondary ion mass spectroscopy.