bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electric Degradation and Defect Formation of Silicon Due to Cu, Fe, and Ni Contamination
Authors: Naito Shunta , Nakashizu Tsuneo 
Published: September 2012

ABSTRACTElectric degradation of silicon wafer due to Cu, Fe, and Ni contamination has been studied using MCZ with low oxygen and CZ wafers. In the cases of Cu and Ni contamination, the electric properties depended on the characteristics of the starting wafers,. especially the type of conductance. The behavior of these metals in the low temperature region played an important role to understand the electric properties. On the contrary, no difference between p- and n-type wafers was observed in Fe contamination in our experiment.The surface defects were observed with high density in the MCZ wafers in Cu contamination. These defects were sensitive to the degradation of the MOS C-t generation lifetime. Making use of this relation, the efficiency of the extrinsic gettering was evaluated.
Evidence for a defect-assisted low resistive conductivity in cw laser beam mixed Au/Te/Au/GaAs contacts.
Authors: Watté J. , Silverans R. E. , Münder H. , Wuyts K. 
Published: September 2012

ABSTRACTCW laser beam mixed Au/Te/Au/n-GaAs contacts have been studied by RBS, Möss-bauer and Raman spectroscopy. For both low and high laser power mixing, resulting in respectively Schottky-type and ohmic contacts, the formation of non-uniformly dispersed Ga2Te3 crystallites was observed. However, for the ohmic contacts the formation of a high density of defect complexes in the GaAs surface layers was revealed. The experimental results suggest that the ohmic conduction mechanism is based on a hopping or a defect assisted tunneling process through the contact zone, consistent with the amorphous/highly defective heterojunction model.
Heat-Treatment Induced Defects in Cz-Silicon
Authors: Dannefaer S. , Bretagnon T. , Abdurahman K. , Kerr D. , Hahn S. 
Published: September 2012

ABSTRACTPositron lifetime results show that vacancies can be retained after growth of Czochralski silicon at concentrations of ∼x1016/cm3. Rapid thermal annealing as well as furnace annealing increase the vacancy concentration. The vacancies are predominantly trapped by oxygen interstitial clusters in lightly B-doped materials, and these complexes appear to have temperature dependent configurations which can be quenched-in by rapid cooling. Heavy Sb doping results in trapping of vacancies by the Sb impuritie
Photoluminescence and Photoacoüstic Spectroscopy of Si Single-and Multi-Step Ingot- and Wafer-Annealed GaAs Crystals
Authors: Ka O. , Oda O. , Shigetomi S. , Ikari T. , Makita Y. , Yamada A. 
Published: September 2012

ABSTRACTSI GaAs crystals submitted to single- or multi-step, ingot-or wafer-annealing are investigated using photoluminescence (PL) and photoacoustic spectroscopy (PA). The near-band-edge PL transitions are well resolved, with a neutral acceptor-bound exciton recombination displayed as a split doublet. The improvement induced by wafer-annealing is illustrated by the absence of additional defect-related transitions found after ingot-annealing. For the room temperature PA measurements, the intensity of a peak occuring at 1.39 eV is shown to lead to an estimation of the arsenic micro-defect density as evaluated by AB etching. The 1.39 eV PA band is also asserted to be the non-radiative recombination path of a 1.482 eV band found in the low-temperature PL spectra.
Detailed Photoluminescence Studies of Heat-Treated InP
Authors: Pressel Klaus , Hiller C. , Bohnert G. , Prinz F. , Dörnen A. 
Published: September 2012

ABSTRACTWe present highly resolved photoluminescence studies on heat-treated nominally undoped InP, which was either unprotected or protected by SiO2 or Si3N4 caps during the annealing procedures. Annealing of InP above 350°C leads to six different sharp emissions in the wavelength range between 8790 and 8900 Å, which are not observed at 4 K in Zn-doped or Fe-doped samples. Based on temperature-dependent photoluminescence studies, time-resolved measurements and preliminary magnetic field studies we ascribe these emissions to isoelectronic bound exciton transitions. It is also shown that the two emissions at 8883 Å (11254 cm-1) (E) and 8889 Å (11246 cm-1) (F) belong to one center. We observe that the lines not only depend on the heat treatment but also on some unintentionally incorporated or residual impurities of a low concentration level. Possible candidates are discussed.
Polysilicon/Silicon Interfaces: Effect of Processing Parameters on Physical and Electrical Properties
Authors: Srikrishna K. , Moinpour M. , Landau B. 
Published: September 2012

ABSTRACTAn arsenic doped polysilicon emitter structure is widely used as an important technology for high speed BiPolar and BiCMOS VLSI devices. The electrical behavior of such emitters is dictated to a large degree by the structure of the polysilicon/silicon interface and the extent of any interfacial oxide. In particular the contact resistance of n+ and p+ diffused regions of the polysilicon is sensitive to the interfacial structure. The microstructure of the polysilicon, in addition to the interface, dictates the junction depth and electrical properties and is determined by the deposition conditions and subsequent doping and annealing processes. The interface itself is defined largely by the cleaning procedure and the initial stages of the deposition process. In this paper we report the effects of process variables, such as deposition temperature, doping and annealing times and temperatures and pre-cleans on the microstructure and electrical properties of poly-emitters.
Carrier Profile Variation of a Channel Conductive Layer Through Phospho-Silicate-Glass Cap Annealing of N+ Si-Implanted GaAs Crystals
Authors: Saito Yasuyuki 
Published: September 2012

ABSTRACTThis paper reports the variation of carrier concentration depth profile in Si-implanted channel conductive layers of liquid- encapsulated-Czochralski- technique (LEC) grown GaAs crystals, the Vth scattering amplitude variation and the averaged Vth variation before and after phospho-silicate-glass (PSG) cap annealing of high-dose-Si-ion implanted crystal layers. Furthermore, the PSG-cap-annealing Vth variation difference between the As-rich LEC crystal and the near-stoichiometric LEC crystal is presented. These results, and carrier depth profile of Si-implanted active layers in LEC GaAs crystals through model of implanted Si atom move (like diffusion) and Si atom capture of a crystal lattice and siteing on lattice are discussed.
Rapid Thermal Annealing of Neutron Transmutation Toped Czochralski Silicon
Authors: Berezina G. M. , Kdrshunov F. P. , Sobolev N. A. , Voevodova A. V. , Stuk A. A. 
Published: September 2012

ABSTRACTThe influence of the rapid thermal annealing (RTA) in comparison with that of the standard furnace annealing (FA) on the electrical parameters and photoluminescence (PL) of Czochralski silicon (Cz Si) subjected to neutron irradiation at various temperatures has been studied. The role of the irradiation temperature on the annealing behaviour of electrical parameters in Cz Si has been established. The possibility of getting neutron transmutation doped (NTD) Cz Si having the calculated resistivity by means of the RTA is shown.
Use of Selective Area Defect Creation for Isolation of III-V Multilayer Structures
Authors: Pearton S. J. , Ren F. , Fullowan T. R. , Katz A. , Hobson W. S. , Abernathy C. R. , Lothian J. R. , D'asaro L. A. , Elliman R. G. , Ridgway M. C. , Jagadish C. , Williams J. S. 
Published: September 2012

ABSTRACTDeep level acceptor and donor centers are created in III-V materials by energetic ion bombardments. The controlled introduction of these centers by selective area implantation can be used to provide electrical and optical isolation of neighbouring devices. We will contrast the implant isolation characteristics of GaAs and AlGaAs with materials such as InP and InGaAs, and also with the ternary compounds InGaP and AllnP, for which there has previously been little information. In all of these materials the as implanted resistivity is controlled by hopping conduction processes, with p « e×p (T 0.25). Post-implant annealing can be used to achieve resistivities of > 108 Ωcm in initially highly doped material provided the implant doses are correctly chosen. These defect engineered regions may be made many microns deep by using overlapping multiple-energy keV implants or a single MeV implant. In the latter case a nearly flat damage profile can be achieved over depths typical of HBT, SEED or long-wavelength laser epitaxial thicknesses. Examples of these devices which rely on controlled introduction of deep level defects for their operation will be given.
Comparison of Mesa- Etched and Ion- Implanted GexSi1-x Heterojunction Bipolar Transistors
Authors: Greve D. W. , Racanelli M. 
Published: September 2012

ABSTRACTWe report a comparison of the characteristics of germanium- silicon base heterojunction bipolar transistors fabricated using mesa- etched and ion- implanted processes. The base currents of both device structures are dominated by peripheral currents associated with the plasma- SiO2 covered junction edge. After an implant damage anneal at 800 or 900 C, the ion- implanted process exhibited the lowest base currents. There was no evidence of strained layer relaxation even for the 900 C anneal.
Device Degradation on a Full-Frame CCD Image Sensor with a Transparent Gate Electrode
Authors: Hseih Biay-Cheng , Kosman S. , Lo Y.C. , Jayakar K. , Mehra M. , Roselle P. , Chang W. C. 
Published: September 2012

ABSTRACTThe electrical and optical properties of Indium-Tin-Oxide (ITO) films, deposited by radio frequency (r.f.) magnetron sputtering, were studied. ITO films, when deposited using optimum sputtering conditions, were reproducibly prepared with resistivity as low as 1.5 × 10−4 Ω-cm and optical transmissivity higher than 80% over the wavelength range of interest. Device stability when ITO is used as a replacement for polysilicon as a gate electrode in silicon charge-coupled device (CCD) image sensors was also studied. After an anneal process at 950 °C in N2 the device degraded. The degradation can be attributed to the generation of oxide charge and interface states in the ITO/SiO2/Si system.
Room Temperature Local Tailoring of Electronic Properties of Hg1-xCdxTe by Application of an External Electric Field
Authors: Gartsman Konstantin , Chernyak Leonid , Marc Gilet Jean , Triboulet Robert , Cahen David 
Published: September 2012

ABSTRACTElectronic properties of originally homogeneous samples of (Hg, Cd)Te, CuInSe2 and (CuAg)InSe2 have been modified on a local scale, in a stable manner, at room temperature, by reverse biasing of small area Schottky contacts on them. This is shown, after the bias voltage is lifted, by I-V measurements and by Electron Beam Induced Current scans. The creation of a clear diode-like, and, in the case of (CuAg)InSe2, transistor-like structure, in the vicinity of the Schottky contact, on a scale of about hundred um, could be explained by electromigration of electrically active ions and by the simultaneous generation of point and line defects. The latter type of defects is revealed for (Hg,Cd)Te by chemical etch, after application of the field.
Improvement of Gate Oxide Integrity Characteristics in CZ-Grown Si Crystals by H2 annealing
Authors: Adachi N. , Nishikawa H. , Komatsu Y. , Hourai H. , Sano M. , Shigematsu T. 
Published: September 2012

ABSTRACTThe mechanism of improvement in gate oxide integrity (GOI) characteristics by H2 annealing in CZ-grown Silicon wafers was investigated. Grown-in defects that are considered to degrade GOI and which can be detected correlatively as 0.1 μm level size pits appearing after SC-1 cleaning, decrease drastically by H2 annealing, while other inert gases, i.e., N2 and Ar, do not exhibit such effect. Besides, H2 annealing shrinks or extinguishes oxygen precipitates significantly, while other gases do not. On the other hand, oxygen outdiffusion is exactly the same among H2, N2 and Ar annealing. From these results, it was concluded that the dominant mechanism for GOI characteristics improvement by H2 annealing is due to decomposition of the grown-in defects having Si-O bonding by the reduction reaction between Si-O bonding and hydrogen, and not due to a mere thermal decomposition enhanced by oxygen outdiffusion.
Control of Ordering-Disordering Defect Parameters for the Realization of Efficient Opto-Electronic Devices
Authors: André J. P. , Bellon P. 
Published: September 2012

ABSTRACTEpitaxial growth of III/V compounds with tight band gap engineering is essential for the realization of efficient optoelectronic devices. Using MOVPE, high quality materials have been grown with anomalous low band gap energy. The order/disorder phenomena and their relation to the band gap energy in the GalnP/AlGalnP system are reported. The effect of the growth parameters on the ordered phase and the band gap Eg will be presented by using TEM and PL characterizations. The growth models will be discussed. The importance of the ordering phenomena will be illustrated by short wavelength laser application, the emission wavelength being as low as 650 ran at 300 K. And a possible future laser structure will be proposed.
Role of Impurities in Reducing Grown-in Dislocations in Compound Semiconductor Crystals
Authors: Sumino Koji 
Published: September 2012

ABSTRACTlmpurity effects on the mobility of dislocations and dislocation generation from generation centers in III - V compound semiconductor crystals are first reviewed on the basis of experimental observations of dynamic behavior of individual dislocations. Dislocation multiplication process is then discussed to account for experimental stress-strain characteristics of these materials obtained in mechanical tests. Using all of such knowledge on dislocation processes in the compound semiconductor crystals, an argument is developed to show how impurities play the role in reducing grown-in dislocations in crystals of these materials. It is shown that immobilization of dislocations caused by impurity gettering plays the decisive role and results in even the growth of dislocation-free crystals.
Disordering and Characterization Studies of 69GaAs/71GaAs Isotope Superlattice Structures: The Effect of Outdiffusion of the Substrate Dopant Si
Authors: Tan T. Y. , You H. M. , Yu S. , Gitesele U. M. , Jäger W. , Zypman F. , Tsu R. , Lee S. -T. 
Published: September 2012

ABSTRACTUndoped 69GaAs/71GaAs isotope superlattice structures grown by MBE on n-type GaAs substrates, doped by Si to ∼3×1018 cm−3, have been used to study Ga self-diffusion in GaAs by disordering reactions. In the temperature range of 850–960°C, the SIMS measured Ga self-diffusivity values showed an activation enthalpy of 4 eV, and are larger than previously compiled Ga self-diffusivity and Al-Ga interdiffusivity values obtained under thermal equilibrium and intrinsic conditions, which are characterized by a 6 eV activation enthalpy. SIMS, CV, and TEM characterizations showed that the as-grown superlattice layers were intrinsic which became p-type with hole concentrations up to ∼2×1017 cm−3 after annealing, because the layers contain carbon. Dislocations of a density of ∼106-107 cm−2 were also present. However, the factor responsible for the presently observed larger Ga self-diffusivity values appears to be Si outdiffusion from the substrate, which was determined using CV measurements. Outdiffusion of Si decreases the n value in the substrate which causes the release of excess Ga vacancies into the superlattice layers where the supersaturated Ga vacancies enhance Ga self-diffusion.
Hydrogen Passivation of Defects in InGaAs/AlxGal-xAs Quantum Wells
Authors: Lord S. M. , Roos G. , Pezeshki B. , Harris J. S. , Johnson N. M. 
Published: September 2012

ABSTRACTThe effect of the diffusion of monatomic hydrogen into InGaAs/AlGaAs quantum wells has been investigated using photoluminescence (PL) and Secondary Ion Mass Spectroscopy (SIMS). The structures were grown by molecular beam epitaxy and hydrogenated with a remote plasma. For In0.2Ga0.8AlxGA1-xAs quantum wells, hydrogenation significant increases the integrated PL intensity from bound excitons at 77 K. The enhancement of the PL is ascribed to removal of nonradiative recombination centers by hydrogen passivation of defects either at the heterojunction interface or within the epilayers. This PL enhancement (and defect passivation) increases as the Al concentration in the AlGaAs layers increases from 0 to 33 at%. A 50% increase of PL intensity is observed for InGaAs/GaAs. For 33 at%, the increase is a factor of 9. We also diffused deuterium into these InGaAs/AlGaAs quantum wells. The enhancement of the PL by deuteration was similar to that by hydrogenation. The isotopie substitution permits the determination of the depth distribution of deuterium in the multilayered structure by SIMS. SIMS results support the conclusion that more defects are passivated in the higher Al concentration samples.
Mechanisms of Transition-Element-Gettering in Silicon
Authors: Gilles Dieter 
Published: September 2012

ABSTRACTThe unique properties of 3d-transition elements in silicon are reviewed that are essential for an understanding of gettering phenomena. Transition-element-gettering techniques are divided into two groups, depending on whether or not the dominant gettering mechanism operates during annealing or cooling down of silicon wafers. Experiments that identify the gettering mechanism are presented for oxygen precipitation-induced gettering (internal gettering) as well as phosphorus-diffusion gettering. It is concluded that only the latter technique operatesduringhigh-temperature treatment.
Defect Control in Cz Silicon
Authors: Kirscht F. G. , Kim S. B. , Yeh J. J. , Wildes P. D. 
Published: September 2012

ABSTRACTGeneric and interaction aspects of oxygen precipitation, related defect formation and denudation in Cz-Si wafers are presented. Bulk defect profiles and homogenization control are shown to be achievable by proper design of post-growth annealing.Gettering-related phenomena are discussed including stacking fault-rich bulk defect structures and peculiarities in different epitaxy systems.
Gettering and Gettering Stability of Metals at Oxide Particles in Silicon
Authors: Falster R. , Laczik Z. , Booker G. R. , Bhatti A. R. , Török P. 
Published: September 2012

ABSTRACTSeveral aspects of metal gettering at internal oxide particle sites in Cz Si have been studied by ‘haze tests’, scanning infra-red microscopy (SIRM) and transmission electron microscopy (TEM). Haze tests indicated that complete gettering of Cu, Ni, Co and Pd can occur even when the amount of oxygen precipitated is below the detectable limit. TEM showed that the gettering of Cu, Pd and Ni proceeds by one of three different self-perpetuating mechanisms involving oxide particles and associated dislocations, the particular mechanism depending on the oxide particle size and the metal type. Haze tests and SIRM showed that for Cu and Ni there were minimum oxide particle number densities for effective gettering, and also maximum oxide particle number densities above which the additional oxide particles played no role in the gettering. These number densities depended on the metal type and specimen cooling rate. For all of these gettering behaviours, mechanisms are suggested to explain the results. The SIRM was also used to investigate for Cu and Ni the thermal stability of the gettering sites and the precipitated metals. The results showed that during repeated heat treatments the gettering occurs by a dynamic process.
Use of Porous Silicon to Minimize Oxidation Induced Stacking Fault Defects in Silicon
Authors: Shieh S.-Y. , W. Evans J. 
Published: September 2012

ABSTRACTPresent methods for minimizing stacking fault defects, generated during oxidation of silicon, include damaging the back of the wafer or depositing poly-silicon on the back. In either case a highly defective structure is created and mis is capable of gettering either self-interstitials or impurities which promote nucleation of stacking fault defects.A novel method of minimizing these defects is to form a patch of porous silicon on the back of the wafer by electrochemical etching. Annealing under inert gas prior to oxidation may then result in the necessary gettering. Experiments were carried out in which wafers were subjected to this treatment. Subsequent to oxidation, the wafers were etched to remove oxide and reveal defects. The regions of the wafer adjacent to the porous silicon patch were defect-free, whereas remote regions had defects. Deep level transient spectroscopy has been used to examine the gettering capability of porous silicon, and the paper discusses the mechanism by which the porous silicon getters.
Phosphorus Gettering by Rapid Thermal Processing
Authors: Hartiti Ecuchaib , Slaoui Abdelilah , Muller Jean-Claude , Siffert Paul 
Published: September 2012

ABSTRACTWe have investigated the rapid thermal diffusion of phosphorus into p-type silicon from a spin-on coated film as a function of the process temperature and time duration. The electron diffusion length LD measurements performed by the Surface PhotoVoltage (SPV) method present evidence for a get-tering phenomena since the LD values of the diffused samples are significantly improved. This result is important for the future of RTP in the area of silicon devices where carrier transport is controlled by the bulk lifetime.
The Effects of Iron Contamination on Thin Oxide Breakdown -Experimental and Modeling
Authors: Henley Worth B. , Jastrzebski Lubek , Haddad Nadim F. 
Published: September 2012

ABSTRACTThe effect of iron contamination in silicon on the properties of thermally grown thin oxides is studied through electrical modelling and experimental MOSDOT testing. Iron concentration is measured using a surface photovoltage / diffusion length technique. Failure mechanisms related to iron contamination are proposed. Contamination limits for various gate oxide thicknesses are defined. Experimental results show that reduction of oxide thickness from 20nm to lOnm requires a reduction in iron conntamination by 100 times.
Oscillatory Indirect Coupling Between Perpendicularly Magnetized Co Monolayers Through Cu (111)
Authors: Gradmann Ulrich , Elmers Hans-Joachim , Kohlhepp Juergen 
Published: September 2012

ABSTRACTCo-Monolayers, prepared by MBE on Cu (111) -surfaces at room temperature and covered by Cu, are ferromagnetic with a Curie-temperature of about 430 K. They are magnetized perpendicularly because of a strong perpendicular magnetic surface anisotropy of the Cu/Co (111) -interface. They provide a remarkably good representation of the 2-dimensional Ising Model. The indirect coupling between these perpendicularly magnetized ferromagnetic monolayers was investigated using samples of type Cu (111) /lCo/DçuCu/lCo/Cu, containing Co/Cu/Co-trilayers composed of Co-Monolayers and a spacer consisting of DCu atomic layers of Cu (111). Torsion oscillation magnetometry of these samples showed clearly a coupling between the monolayers with an oscillatory dependence on DCu. The amplitude of the oscillation is strongly reduced if the coupled Co-films consist of 5 ML instead of 1 M.L. The present controversy on the presence or absence of antiferromagnetic and oscillatory indirect coupling in the Co/Cu (111) -system is discussed in the light of these experiments. The discussion shows that the oscillatory coupling is an intrinsic property of ideal (111)-structures, and can be understood by the RKKY-type theory of indirect coupling between ferromagnetic Monolayers. The usual application of this theory to the coupling between thicker films is justified. However, in the fcc (111) -system there is apparently a specific barrier against complete coalescence, resulting in a tendency to retain holes and channels in the Cu-spacer. This tendency is stronger in flat single-crystal samples than in sputtered films with high densities of atomic steps. Apparently, this results in competing ferromagnetic hole coupling which may more or less completely obscure the intrinsic oscillatory coupling, preferentially in samples grown on extremely flat single crystal surfaces.