bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural Analysis of Silicon Doped by Plasma Source Ion Implantation
Authors: Matyi R.J. , Chapek D.L. , Conrad J.R. , Felch S.B. 
Published: March 2011

ABSTRACTWe have used high resolution x-ray diffraction to analyze the structural changes that accompany boron doping of silicon by BF3 plasma source ion implantation (PSII). Triple crystal diffraction analysis of as-implanted PSII doped silicon showed little excess x-ray diffuse scattering, even when analyzed using the asymmetric (113) reflection for increased surface sensitivity. This result suggests that PSΠ is capable of providing high dose implantation with low damage. Annealing of the PSII-doped silicon showed the development of a compressive surface layer, indicated by enhanced x-ray scattering directed perpendicular to the surface. Virtually all of the scattering from the annealed samples was concentrated in the so-called “surface streak” which arises due to dynamical diffraction from the perfect crystal Si structure. Little if any diffuse scattering due to kinematic scattering from crystal defects was detected. These observations indicate that plasma source doping can be used to achieve both a shallow implant depth and an extremely uniform incorporation of boron into the silicon lattice.
Formation of Double-Height Si(001) Steps by Sputtering with Xe Ions - A Computer Simulation
Authors: Heinig K.-H. , Stock D. , Boettger H. , Zinovyev V.A. , Dvurechenskii A.V. , Aleksandrov L.N. 
Published: March 2011

ABSTRACTA study of the recently observed double-height Si(001) step formation by sputtering with low-energy Xe ions is presented. The modeling of the process has been separated in two stages: (i) Molecular dynamics (MD) simulations of the interaction of 225 eV Xe ions with Si(001) surfaces and (ii) calculation of the step kinetics by reaction-diffusion equations. It is found that a single Xe ion produces surface vacancies arranged in one cluster, some adatoms and on the average one sputtered atom. For adjacent terraces on a vicinal Si(001)-(2 × 1) surface separated by SA- and SB-steps, respectively, the adatom diffusion as well as their attachment and detachment at steps and vacancy clusters determines the kinetics of the steps and results in double-height Si(001) steps.
Reactive Ion Etching Processes for Amorphous Germanium Alloys
Authors: Kuo Yue 
Published: March 2011

ABSTRACTThis paper presents results on reactive ion etching (RIE) processes of amorphous germanium (a-Ge:H), germanium silicon alloys (a-GeSix:H) and germanium oxide (GeOx). Their process characteristics are compared with those of the amorphous silicon (a-Si:H) and silicon nitride (SiNx). Various combinations of feeding gases, i.e., from CF4, CF2Cl2, CH3F, and O2, over a pressure range of 100 to 300 mTorr and a power range of 500 to 1500 W were used in this study. The following conclusions are drawn from the results: 1) the a-Ge:H and a-GeSix:H etch mechanisms are similar to that of a-Si:H, but the former have higher etch rates than the latter; 2) a-GeSix:H etch rate falls between those of a-Ge:H and a-Si:H; 3) the GeOx etch mechanism is similar to that of SiNx; 4) although plasma phase chemistry, ion bombardment energy, and surface reactions are all important to the etch process, the film component selectivity is greatly dependent on the feeding gas; 5) to obtain a high etch selectivity between a-GeSix:H and PECVD SiNx a chlorine-containing gas has to be used; 6) RIE plasma damage to a-Si:H TFT is decreased when it is covered with an a-GeSix:H layer.
High Resistivity in N-Type InP and InGaAsP by He+ Ion Induced Amorphization.
Authors: Sargunas V. , Comedi D. , Zhao J. , Jankowska K. , Thompson D.A. , Simmons J.G. 
Published: March 2011

ABSTRACTChanges in the resistivity of n-type InP and InGaAsP by He+ ion implantation have been investigated at implant temperatures of 60-523K. The highest resistivities are achieved at the lowest temperatures under the conditions where the dose is sufficient to render the implanted region amorphous, as indicated by Rutherford backscattering/channeling measurements. Anneal data indicates that the high resistivities achieved via amorphization are stable to higher temperatures than when the samples remain crystalline after implantation.
Divacancy Annealing in Silicon Monitored by Differential Calorimetry and Infrared Absorption Spectroscopy
Authors: Roorda Sjoerd 
Published: March 2011

ABSTRACTAnnealing of divacancies in crystalline Si has been characterized by differential scanning and isothermal calorimetry and infrared absorption spectroscopy. Si discs of 0.1 mm thickness have been implanted with 3.4 MeV protons. Scanning calorimetry shows a relatively sharp peak centered around 425 K and a broader feature ranging from 450 to 620 K. The isothermal heat release at 620 K exhibits a single exponential rather than a bimolecular decay. As the annealing progresses, a decrease in infrared absorption at 1.8 µm is observed which is directly related to the annealing of divacancies.
Formation and Thermal Stability of End-of-Range Defects in Ge Implanted Silicon
Authors: Seibt M. , Imschweiler J. , Hefner H.-A. 
Published: March 2011

ABSTRACTBy means of transmission electron microscopy we have studied the redissolution of extended end-of-range defects during high temperature rapid thermal annealing. We find, that after the transformation of initially present {113} stacking faults into energetically more favorable structures, each type of end-of-range defect establishes its individual redissolution rate with {111} faulted loops being the most stable configuration.
Extended Defects in Fe-Implanted InP After Thermal Annealing
Authors: Frigeri C. , Bocchi C. , Carnera A. , Gasparotto A. , Gambacorti N. , Longo F. 
Published: March 2011

ABSTRACTThe recovery of the implant-induced damage and the defects present after thermal annealing at 650 °C in Fe-implanted InP have been investigated by TEM, RBS and X-ray diffractometry as a function of the annealing time that was varied betweeen 0.5 and 2 h. The near-surface damaged layer was removed only for annealing times ≥ 1.5 h. The annealed samples contained stacking fault tetrahedra of vacancy type, extrinsic dislocation loops and microdefects. These extended defects were mostly localized in a band corresponding to the region of transition between amorphous top layer and crystalline substrate as was detected in the as-implanted sample. Stacking fault tetrahedra and loops have also been observed before and beyond this band, respectively. Such defects could be due to either shear strains at the recrystallization front or implant-induced point defects.
Solid-Phase Epitaxial Crystallisation of GexSi1-x Alloy Layers
Authors: Elliman Robert G. , Wong Wah-Chung , KringhØj Per 
Published: March 2011

ABSTRACTThermally-induced solid-phase epitaxial crystallisation (SPEC) and ion-beam-induced epitaxial crystallisation (IBIEC) of amorphous GexSi1-x alloy layers is examined for three different starting structures: a) strain-relaxed alloy layers of uniform composition, b) strained alloy layers of uniform composition, and c) Ge implanted Si layers. Thermal annealing experiments show that the activation energy for strain-relaxed alloys is higher than that expected from a simple extrapolation between the activation energies of Si and Ge, and exceeds that of Si for x ≤ 0.3. Experiments on thin strained layers show that MBE grown strained layers which are stable during annealing at 1100°C for 60 s are also fully strained after SPEC, whereas layers which relax during annealing at 1100°C also relax during SPEC. Experiments on ion-implanted GeχSiι_x structures show that fully strained Si/GexSi1-x /Si heterostructures can be fabricated for ion fluences below a critical fluence, and as for uniform alloy layers that this critical fluence is accurately predicted by equilibrium theory. Strain relaxation during SPEC of uniform alloys and implanted structures is shown to be correlated with a sudden reduction in crystallisation velocity which is believed to be caused by stress-induced roughening or faceting of the crystalline/amorphous interface. IBIEC of thick (800 nm) implanted layers is shown to be limited by competition from ion-beam induced random crystallisation, while thin (120 nm) uniform alloys and implanted structures are shown to crystallise ephaxially and to exhibit similar behaviour to thermally annealed samples under certain conditions.
Ion Beam Induced Epitaxial Crystallization of Single Crystalline 6H-SiC
Authors: Heera V. , Kögler R. , Skorupa W. , Glaser E. 
Published: March 2011

ABSTRACTFor the first time, ion beam induced epitaxial crystallization (IBIEC) has been found in SiC. The effect of 300 keV Si+ irradiation through an amorphous surface layer in single crystalline 6H-SiC at 477±5°C has been investigated by RBS/C and XTEM. A shrinkage of the amorphous layer was found after ion irradiation at this temperature which is caused by both an ion dose independent thermal regrowth of about 20 nm and an additional ion beam induced epitaxial crystallization with a rate of about 1.5 nm/ 1016 cm-2.
Density Reduction: A Mechanism for Amorphization at High Ion Doses
Authors: Specht E.D. , Walko D.A. , Zinkle S.J. 
Published: March 2011

ABSTRACTAt cryogenic temperatures, the accumulation of vacancy-interstitial pairs in Al2O3 from atomic displacements associated with ion implantation produces amorphization. At room temperature, these pairs recombine, and amorphization occurs only at high doses. X-ray reflectivity measurements show that amorphization of the surface of Al2O3 implanted at room temperature with 160 keV Cr+ ions is preceded by a progressive reduction in near-surface density. Monte Carlo simulations show that this density reduction can be accounted for by high-energy-transfer collisions which knock atoms deep into the target, leaving widely separated vacancies and interstitials, which do not recombine. Electron microscopy shows that at least some of these vacancies condense into voids. We propose that this reduction in near-surface density can lead to amorphization at high doses. We present simple approximations for the density reduction expected for different ions and targets.
Electron Energy Dependence of Amorphization in Zr3Fe
Authors: Motta A.T. , Howe L.M. , Okamoto P.R. 
Published: March 2011

ABSTRACTThis paper reports the results from a study conducted to determine the effect of electron energy on the dose-to-amorphization of Zr3Fe at 23-30 K. Zr3Fe samples were irradiated in the HVEM at Argonne National Laboratory, at energies ranging from 200 to 900 keV. Amorphization occurred at electron energies from 900 keV down to 250 keV. Three distinct regions were observed: between 900 and 700 keV amorphization occurred at a constant low dose of ~ 4 × 1021 e cm-2; a higher plateau at 1022 was observed between 600 and 400 keV, and finally there was a sharp increase in the dose-to-amorphization below 400 keV, so that at 250 keV the necessary dose was an order of magnitude higher than that at 900 keV. In the region below 400 keV there was evidence of a dependence of the dose-to-amorphization on the orientation of the sample with respect to the electron beam. The results can be analyzed in terms of a composite displacement cross section dominated at high energies by displacements of Zr and Fe atoms, by displacements of Fe atoms at intermediate energies and of secondary displacements of lattice atoms by recoil impurities at low energies.
MeV Boron Implantation and Masking
Authors: Lavine James P. , Filo A. J. , Losee D. L. , Guidash P. A. , Lee S.-T. , Braunstein G. H. , Kosman S. L. , Kyan H. 
Published: March 2011

ABSTRACTBoron depth distributions are reported for MeV implants into silicon through a variety of masking materials. Silicon is implanted with boron through a 0.1-µm-thick layer of thermally grown silicon dioxide. Secondary ion mass spectrometry (SIMS) shows the projected ranges agree within 10% with data reported in the literature and with results from the computer program TRIM. Silicon dioxide, photoresist, and metal layers are used to mask the high-energy boron implants. The SIMS results indicate that TRIM overestimates the energy loss of MeV boron ions as they pass through photoresist and/or silicon dioxide.
Thermally Stable Oxygen and Nitrogen Implant Isolation of C-Doped Al0.35Ga0.65As
Authors: Zolper J. C. , Sherwin M. E. , Baca A. G. , Schneider R. P. 
Published: March 2011

ABSTRACTOxygen and nitrogen ion implantation have been applied, for the first time, to C-doped Al0.35Ga0.65As layers produce high resistivity regions (ps ≥ 1×1010 Ω/□) that are stable after annealing at 900 ºC. A dose threshold for stable compensation for both O and N ions was found above 8×1013 cm-2 for samples doped at 2×1018 cm-3. Although O implantation has been reported to form stable compensation in Si-doped and Be-doped AlGaAs, the ability of nitrogen implantation to produce thermally stable compensation has not been previously reported and may be due to a C-N complex. The existence of this C-N complex is supported by results for O- and N-implants into C-doped GaAs where N formed thermally stable compensation but O did not. Sheet resistance data versus anneal temperature and estimates of the depth of the defect levels are reported. This result will have application to heterojunction bipolar transistors and complementary heterostructure field effect transistor technologies that employ C-doped AlGaAs or GaAs layers along with high temperature post-isolation processing.
Erbium Ion Implantation for Optical Doping
Authors: Polman A. 
Published: March 2011

ABSTRACTErbium is a rare-earth ion which, when incorporated in a solid in the trivalent state, shows characteristic intra-4f emission at 15 µm, an important telecommunication wavelength. A review is given of recent work in the area ofEr ion implantation into soda-lime silicate and AI2O3 optical waveguide films, LiNbO3 and silicon. Structural and optical characteristics are discussed and future challenges for this exciting new field are described.
Studies of Dislocation Formation in Annealed Self-Ion Irradiated Silicon
Authors: Goldberg R. D. , Simpson T. W. , Mitchell I. V. , Schultz. P. J. 
Published: March 2011

ABSTRACTVariable energy positron annihilation and Rutherford backscattering spectroscopy have been used to investigate the evolution of secondary defects during the annealing of self-ion irradiated silicon. Evidence supporting the existence of both vacancy- and interstitially-based defects after high temperature anneals is presented. Dopant type and irradiation temperature have both been shown to influence the structure of the defects whose onset can be manipulated via the implantation flux.
Erbium Implantation in Silicon: A Way Towards Si-Based Optoelectronics
Authors: Priolo F. , Franzó G. , Coffa S. , Polman A. , Bellani V. , Carnera A. , Spinella C. 
Published: March 2011

ABSTRACTIn this paper our recent work on erbium implantation for optical doping of silicon is reviewed. It is shown that O co-implantation plays a key role both in providing Er with the appropriate chemical surrounding and in allowing the incorporation of high Er concentrations in thick Si layers without the formation of twins and/or precipitates. The luminescence intensity in Er and O co-implanted samples shows a much weaker temperature dependence (a decrease by a factor of 30 from 77K to 300K) than in samples without O (a decrease by 3 orders of magnitude in the same temperature range). This allowed us to observe room temperature photo- and electro-luminescence in Er and O co-doped samples. The temperature dependence of the luminescence in these samples has been determined to be due to non-radiative de-excitation processes. These data are reported and discussed.
Nanosize Metal Alloy Particle Formation in AG and CU Sequentially Implanted Silica
Authors: Zuhr R. A. , Magruder R. H. , Anderson A. , Wittig J. E. 
Published: March 2011

Abstract:A series of high purity silica samples were sequentially implanted with Ag and Cu ions at energies such that the depth distributions for each of the ions overlapped. The samples were characterized by RBS, TEM and optical spectroscopy. The optical response was found to be dependent on the order of sequential implantation, as well as the relative concentration of the implanted elements. The changes in the optical response are attributed to composition changes of the metal colloids that are formed as a result of alloying of the sequentially implanted metal ions, as well as to changes in the size the colloids.
Fluorine-Enhanced Si:Er Light Emission
Authors: Ren F.Y.G. , Michel J. , Jacobson D.C. , Poate J.M. , Kimerling L.C. 
Published: March 2011

ABSTRACTAn erbium-fluorine complex is 100 times more effective than an erbium-oxygen complex in generating light emission at 1.54 µm in Si:Er. The luminescence light intensity is linearly proportional to the total retained F atoms in Si after heat treatment. F enhancement in light emission in Si:Er is eventually limited by the damage associated with high dose F implantation. The optimum annealing temperature to achieve the maximum intensity is found to decrease slightly from 1000ºC to 800ºC as the initial F implanted concentration increases. The Si:Er heat treatment process and the optimum processing window are determined by the interaction of three different processes: damage recovery/complex formation, F out-diffusion and Er-F complex dissociation.
Characterization and Applicatons of Arsenic-Implanted Mocvd-Grown GaAs Structures
Authors: Namavar Fereydoon , Kalkhoran N. , Cremins A. , Vernon S. 
Published: March 2011

ABSTRACTArsenic precipitates can be formed in GaAs using arsenic implantation and annealing, thereby producing very high resistivity (surface or buried) GaAs layers. Arsenic-implanted materials are similar to low-temperature (LT) GaAs:As buffer layers grown by molecular beam epitaxy (MBE) which are used for eliminating side- and backgating problems in GaAs circuits. Arsenic implantation is not only a simple and economical technique for device isolation but also can improve the quality of individual devices. Through surface passivation, arsenic implantation can reduce gate-to-drain leakage in and enhance the breakdown voltage of GaAs-based metal semiconductor field-effect transistors (MESFETs) and high electron mobility transistors (HEMTs). High resistivity thin surface layers may be used as gate insulators for GaAs-based metal insulator semiconductor (MIS) FETs, leading to the development of a novel GaAs-based complementary metal insulator semiconductor (CMIS) technology like advanced Si-based complementary metal oxide semiconductor (CMOS) technology but with higher radiation hardness and operational speed.
The Tribological Properties for Pulsed W+C and Mo+C Dual Implanted H13 Steel
Authors: Tonghe Zhang , Fuzhong Wei , Jun Chen , huixing Zhang , Xioji Zhang 
Published: March 2011

ABSTRACTThe tribological properties for pulsed W+C and Mo+C dual implanted H13 steel are given in this paper. The pulsed ion of W, Mo and C were implanted at 40KV to dose of (3~12)×1017/cm2 with ion flux from 25 to 100µA/cm2 using MEVVA implanter. The results show that the wear resistance life and hardness of the dual implanted H13 steel increase 2~3 times. The comparison of dual implantation with single implantation shows that the dual implantation is better. The tribological properties of W+C dual implanted H13 steel is better than Mo+C dual implanted H13 steel. The TEM and X-ray diffraction analysis show that the super high hardening dispersed phases of MoC, MoCx, WC and W2C were formed during ion implanting. The iron compounds of tungsten and molybdenum and iron carbides were obtained also. That is, the strengthening effect in H13 steel of phases MoC and WC is better than FeMo, Fe3Mo2, Fe2W and Fe7W6.
Large Scale Ion Beam Equipment and Processing - Review of Ammtra Project -
Authors: Matsuda Koji 
Published: March 2011

An R&D project of large scale ion beam equipment and processing is being carried out from 1986 till 1994. The project includes R&D of five ion beam systems and three material processes for surface modification. The five equipment R&D projects are:(1)High current metal ion beam system,(2)Integrated high current ion beam system,(3)Ionized multiple beam system with high deposition rate,(4)High energy ion beam system,(5)Gas-phase focused ion beam system.The three materials processing R&D projects are:(1)Glass surface modification,(2)Metal surface modification,(3)Low scattering multilayer film deposition. This paper reviews recent progress on development of the project. This work was conducted in the program: ’Advanced Material Processing and Machining System’ consigned to AMMTRA from the New Energy and Industrial Technology Development Organization, which is carried out under the Industrial Science and Technology Frontier Program enforced by the Agency of Industrial Science and Technology of Japan.
In-Situ Control of Wafer Charge Neutralization During High Current Ion Implants
Authors: Shauly E.N. , Koltin E. , Munin I. , Avrahamov Y. 
Published: March 2011

ABSTRACTIon implantation in semiconductor devices frequently leads to a substantial wafer surface charge build up. Control of this charge during high current implantation is a major process issue, as it may affect the yield and reliability of thin dielectric layers. In addition, the charge build up may affect the ion beam resulting in a non-uniform implant and a reduction in device yield. Control of a specific machine parameter, that will give the charge condition of the ion implanter will enable to neutralize the charge build up.In this study, Disk Current Monitoring (DCM) is shown to be a reliable method for monitoring the Electron Shower (ES) performance in real time. A correlation was found between DCM level and yields, and between DCM level and breakdown voltage, as well as different maintenance activities regarding me ES. A simple 5 steps method is described to achieve a reliable, real time charge monitor, to insure operation within the “High Yield Range”.
Ion Implantation Monitoring of GaAs Using Thermal Waves
Authors: Garcia R. , Jaquez E. J. , Culbertson R.J. , D'Acosta C. , Jasper C. 
Published: March 2011

ABSTRACTLaser modulated thermoreflectivity, also called thermal wave technology, has been used in recent years to monitor ion implantation dose by monitoring the damage due to implantation. The thermal properties which are affected by lattice perturbations and other crystal imperfections are tracked by this technique. A gauge capability study was performed on the Thermawave TP300 for monitoring ion implantation of GaAs wafers. The results are presented. In order to determine the sensitivity of the technique to changes in dose, a matrix of GaAs and Si wafers was measured. During this study a downward trend was observed in the repeatability of our results. It is shown that damage to a sample during implantation will relax to a certain degree at room temperature. This damage relaxation can take up to 80 hours at room temperature and can be observed using thermal waves. It is shown that “hot wafer decay” follows a logarithmic decay which is indicative of a diffusion process. At 180°C the decay lasts less than 1 minute which indicates that the defects causing this phenomenon have a low activation energy.