bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deep Diffusions and Soi Layers Produced by Rapid Thermal Processing for Smart Power Applications
Authors: Dilhac J-M. , Cornibert L. , Ganibal C. 
Published: April 2011

ABSTRACTPower devices often contain very deep boron diffusions extending through the thickness of the wafer to create junction isolation. In this paper we first report our investigations to replace the standard solid-state deep diffusion, with Temperature-Gradient Zone Melting (TGZM). During TGZM, a molten silicon/aluminium solution moves through a Si wafer in minutes, leaving a highly Al doped trail behind it. The liquid phase diffusion is driven by the vertical thermal gradient created in the wafer by a properly designed RTP.On the other hand, for the purpose of high voltage (> 400V) smart power applications, substrates with localised and thick SOI layers are needed. We also present a method for recrystallization of thick poly silicon films by Lateral Epitaxial Growth over Oxide (LEGO), using a similarly designed RTP.The two processes, that is LEGO and TGZM, use a Rapid Thermal Processor and are compatible. The RTP is specially designed to create a thermal gradient perpendicular to the wafer surface.
Near and SUB-keV Boron Implantation and Rapid Thermal Annealing: a Sims and Tem Study
Authors: Lcurrent M. , Foad M. A. , England J. G. , Lopes D. , Jones C. , Su D. 
Published: April 2011

ABSTRACTAtomic profiles (SIMS) and cross-section TEM images of selectively etched, annealed profiles were studied for Boron energies from 20 da eV (200 eV) to 10 keV and RTP anneals at 900, 975 and 1050 C Consistent variations of dopant depth was obtained over this process range. TEM images showed evidence of lateral dopant variation near the edges of poly-Si gate structures, perhaps an effect of lateral straggling and reflection of ions from the poly mask.
Enabling Thermal Processing of High and Low Dielectric Constant Materials
Authors: Thakur R. P. S. , DeBoer S. J. , Singh R. 
Published: April 2011

ABSTRACTThe focus of ULSI electronics is shifting rapidly towards the development and integration of various low and high dielectric constant materials. Memory manufacturers are driving the quest for integration-friendly, high dielectric constant materials, while the logic makers are seeking materials with the lowest possible dielectric constant to use as interlayer dielectrics for their multilayer backend needs. Both of these categories of materials need the highest possible level of reliability, integrability, and manufacturability in the current and upcoming real world. Strong development emphasis in improving the structural aspects of these materials is needed more now than ever before both in university laboratories and industrial R&D. An intense focus on these materials demands immediate, improved, and innovative process solutions. One key process area is the thermal engineering and processing of these materials and hence is the focus of this paper.In this paper, we present recent results from both university and industry process development work. We compare and contrast the thermal process requirements of some enabling materials with dielectric constants ranging from 2 to more than 100. The examples in our study encompass materials such as Teflon™, PLZT, cell nitride, and tantalum pentoxide. The enhancements in the structural and electrical performance of these materials as a function of thermal cycles used either for deposition or annealing is demonstrated through various examples.
Nitric Oxide Rapid Thermal Nitridation of Thin Gate Oxides
Authors: Kuehne J. , Hattangady S. , Piccirillo J. , Xing G. C. , Miner G. E. , Lopes D. 
Published: April 2011

ABSTRACTNitric oxide rapid thermal nitridation of thin gate oxides was investigated. Oxides from 25 to 55 Å were grown in O2 and subsequently nitrided in a nitric oxide (NO) ambient using an Applied Materials RTP Centura chamber. Nitrogen incorporation and film thickness growth during NO nitridation were evaluated. Peak nitrogen incorporation was most strongly influenced by temperature and time, with moderate influence by initial oxide thickness, and no significant influence due to NO flow rate. Peak nitrogen concentrations ranged from 1 to 9 atomic percent as characterized by Secondary Ion Mass Spectrometry (SIMS) analysis. Oxide growth during nitridation ranged from 2 Å to 11 Å with no degradation in uniformity. These data were used in the design of two 40 Å oxynitride processes incorporating 2 and 4 peak atomic percent nitrogen. High quality MOS capacitors were demonstrated with these dielectrics. Performance was compared against a baseline furnace process as well as non-nitrided RTO. Throughout this work, the chamber integrity was monitored using visual inspection, minority carrier lifetime (MCLT) and surface photovoltage (SPV). No contamination, corrosion or other degradation of the process chamber was observed in over 6 months' operation with over 700 NO processes completed. The controllability, uniformity and high nitrogen incorporation of rapid thermal NO nitridation make it an attractive process for deep sub-micron gate insulators.
A Generalized Model of Beryllium Diffusion in InGaASs Epitaxial Structures Under Point Defect Nonequilibrium Conditions
Authors: Gautier S. , Koumetz S. , Marcon J. , Ketata K. , Ketata M. , Gautier B. 
Published: April 2011

ABSTRACTBeryllium diffusion during post-growth annealing is investigated in InGaAs epitaxial layers. Indeed, this undesirable diffusion may occur during thermal treatments of InGaAs/lnP Heterojunction Bipolar Transistors (HBT's), which can generate a limitation of frequency performances of these devices. Epitaxial structures have then been grown, one set by Chemical Beam Epitaxy (CBE), and another one by Gas Source Molecular Beam Epitaxy (GSMBE). The post-growth Rapid Thermal Annealing (RTA) was then performed, and Secondary Ion Mass Spectrometry (SIMS) has been used to characterize the Be depht profiles.In parallel with our experimental study, we propose two models of Be diffusion in InGaAs in the case of point defect nonequilibrium. First, a Kick-out Diffusion model considering neutral Be interstitial species and charged point defects has been studied. Then, a Generalized Substitutional-Interstitial Diffusion model based on simultaneous diffusion by Dissociative and Kick-out mechanisms is proposed. Good agreements between experimental depth profiles and simulated curves have been obtained.
Grain Enhancement of Thin Silicon Layers Using Optical Processing
Authors: Sopori B. L. , Alleman Jeff , Chen W. , Tan T. Y. , Ravindra N. M. 
Published: April 2011

ABSTRACTWe describe a new technique for producing large-grain, poly-Si thin films on low-cost glass substrates for solar cell applications. A layer of fine-grain poly-Si is deposited on metal-coated substrate followed by a grain enhancement using optical/thermal annealing at low temperatures (∼ 500 °C). The results show that in thin-layer silicon, less than 3 microns, grains can be formed in a short time (few minutes) with grain sizes larger than the film thickness. The possible mechanisms involved in this process are also presented.
Temperature Estimation and Precision Control of RTP Systems by Multi-Zone Lamp Interference and Wafer Emissivity Compensation I: Model Identification
Authors: Belikov Sergey , Kamali Jalil , Lee Yong Jin , Moslehi Mehrdad 
Published: April 2011

ABSTRACTRTP temperature measurement using conventional pyrometric technique has serious limitations such as uncertainty of emissivity, lamp interference, and window/chamber heating effect. In this paper, we propose to compensate for these effects using a real-time computational algorithm based on physical model of pyrometric detectors and wafer temperature dynamics. We consider an RTP system for processing 200 mm wafers with five circular zones of heating lamps and ten pyrometric sensors, five of which measure the radiation from five optically isolated dummy lamps and the rest measure the radiation of the wafer back side at different radial positions. Thermocouple measurements are also used to identify the model parameters. Part I of the paper is concerned with modeling and parameter identification.
Selective Si/SiGe Heterostructures for Advanced CMOS and BiCMOS Technologies
Authors: Regolini J. L. 
Published: April 2011

ABSTRACTNew device architectures for advanced Integrated Circuits (IC) have been studied within the frame of our GRESSI Program through the technological development of the well known but less implemented low temperature selective epitaxial Si and SiGe films. High performance IC manufacturing requirements, such as large diameter wafer uniformity, reproducibility, throughput and reliability can be met by commercial integrated processing, single wafer cluster tools.Using an industrially available CVD single wafer reactor, special care has been taken to integrate these films into advanced CMOS and BiCMOS processes with a minimum of drawbacks. Indeed, the Si and SiGe growth rate dependence on filling ratio as well as full selectivity are major issues. The loading effect as a function of temperature, gas mixture, Ge and dopant incorporation has been studied and optimized for these applications.Finally, device results are compared between conventional and developed architectures showing real improvements with minimum process modifications.
Critical Technologies for Poly-Si TFT in High Resolution AM-LCD
Authors: Wu I-Wei 
Published: April 2011

ABSTRACTPolycrystalline silicon (p-Si) TFT offers higher aperture ratio with integrated driver circuits compared to the conventional a-Si TFT in AM-LCD application. The advantages of the p-Si TFT as the pixel switching element will be more pronounced for AM-LCDs with large number of scan lines and/or high pixel density. This paper reviews challenges and issues associated with the technology of p-Si TFT, particularly in active silicon layer deposition, solid phase and laser crystallization, hydrogenation, leakage current, performance of different device architectures and reliability. Critical issues affecting the p-Si TFT AMLCD pixel design are analyzed, including: lithographic resolution and overlay accuracy, pixel density and aspect ratio, display format, storage to LC capacitance ratio, and gate dielectric thickness. Predictions on the regimes of dominance for different flat-panel technologies by advantages in performance and-or cost with respect to panel size and pixel density will be presented.
A Novel Multi-Channel Poly-Si TFT Improving Hydrogen Passivation
Authors: Park C. M. , Jeon J.-H. , Yoo J.-S. , Han M.-K. 
Published: April 2011

ABSTARCT:We have fabricated a new multi-channel polycrystalline silicon thin film transistor (ploy-Si TFT), of which structure may be more effectively hydrogenated than conventional multi-channel poly-Si TFT. The new multi-channel TFT has stripe-cuts in gate electrode so that more hydrogen radicals penetrate into the gate oxide and passivate the active poly-Si layer. After 90 min. hydrogenation of the new device, the electrical characteristics such as threshold voltage and field effect mobility are improved more than those of conventional device.The new multi-channel poly-Si TFT, which receives more hydrogen radicals thorough gate oxide than the conventional multi-channel TFT, can be hydrogenated effectively in long channel devices. Besides the improvement of the device characteristics, our experimental results show that the dominant hydrogenation path is the diffusion though the gate oxide.
The Performance of Polycrystalline Silicon Thin film Transistors and CMOS Driving Circuits with Various Active Films
Authors: Yoo Juhn-Suk , Kim Cheon-Hong , Park Ki-Chan , Han Min-Koo 
Published: April 2011

ABSTRACTThe performance of poly-Si TFTs and CMOS circuits with various active films prepared by different deposition processes and annealing methods, such as SPC(Solid Phase Crystallization) and ELA(Excimer Laser Annealing), have been investigated. We have examined the effects of DC characteristics of poly-Si TFT, such as mobility, threshold voltage and ON- OFF- current level, on the dynamic performance of the CMOS circuits.We have fabricated poly-Si TFT devices and CMOS circuits with various process conditions, such as active layer preparation source gases, annealing method, film thickness and source/drain impurity doping. The TFTs with ELA active films exhibit much higher field effect mobility and ON/OFF current ratio than those with SPC active film due to low intragranular trap state density. The TFTs with active film deposited using Si2H6 have higher mobility and sub-threshold slope than those with active film deposited using SiH4 because of the large poly-Si grain size and less grain boundary defects. We have observed that the device ON-current, mobility and VTH are the dominant characteristics to control the operation speed of CMOS circuits. We have also found that the effects of active film thickness and source/drain doping process on the performance of CMOS ring oscillator may not be neglected and that it should be optimized for AMLCD applications.
Field Emission from Tetrahedrally Bonded Amorphous Carbon
Authors: Milne W. I. , Robertson J. , Satyanarayanan B. S. , Hart A. 
Published: April 2011

ABSTRACTA series of tetrahedrally bonded carbon (ta-C) films have been produced using a Filtered Cathodic Vacuum Arc System. The threshold field and current densities achievable have been investigated as a function of sp3/sp2 bonding ratio and nitrogen content. Typical undoped ta-C films have a threshold field of 15–20V/μm and optimally nitrogen doped films exhibit threshold fields as low as ∼ 5 V/μm. Current densities of typically 10-4 A/cm2 at an applied field of 20V/micron were also obtained.
Rare Earth Doped Porous Silicon Prepared by Electro-Chemical Method
Authors: Zheng W. H. , Gong M. L. , Lian D. L. , Wong W. K. , Cheah K. W. 
Published: April 2011

ABSTRACTWe have carried out an investigation of the electro-chemical doping (ECD) of porous silicon (PS) with rare earth elements, especially Er was chosen for the main doping element in our work. Under certain conditions, after doping a blue shift was shown in the visible range photoluminescence (PL), and enhancement of PL intensity was observed. We address this that the impurity states in forbidden gap increase the optical probability of trapping carriers and the optical transition probability. Moreover, in the Infrared (IR) range, luminescence is observed around 1.54μm at room temperature and is assigned to the optical transitions from intra-4f energy levels of Er3+. X-ray Photo-electronic Spectroscopy (XPS) showed that at least 3 atomic percen of the rare earth element has been incorporated into porous silicon layer. In conclusion, by choosing suitable electrolyte, we successfully doped rare earth elements into porous silicon by electro-chemical method.
Electrical and Optical Properties of Low Dielectric Constant Planarization Polymer for High-Aperture-Ratio a-Si:H TFT-LCDs
Authors: Lan Je-Hsiung , Chou Tsung-Kuan , Chiang Chun-Sung , Kanicki Jerzy 
Published: April 2011

ABSTRACTWe have evaluated the electrical and the optical properties of a planarization polymer (benzocyclobutene; BCB) having a dielectric constant of 2.65 for the application to high aperture-ratio a-Si:H TFT-LCDs. An average optical transmittance of 96 % was found for the BCB film having a thickness of 3 μm in the visible-light region (400–700 nm) of the absorption spectrum. Experimental results showed that the back-channel etched a-Si:H TFT electrical performance was not significantly affected by the BCB passivation. In addition, the three-dimensional analysis of the coupling capacitances between ITO pixel electrode and metal bus lines have indicated that the low dielectric constant of planarization polymer is necessary for the application of this material to the high-aperture-ratio a-Si:H TFT-LCDs. Finally, we have established that for a given tolerance margin, a certain value of polymer thickness is needed to suppress the feed-through voltage and the vertical cross-talk between pixel electrode and metal bus lines.
Annealing Characteristics of Electron Beam Evaporated Magnesium Oxide Thin Film
Authors: Kang Y. C. , Baik J. B. , Lee B. H. , Choi J. H. , Kim J. M. , Park K. Y. 
Published: April 2011

ABSTRACTThe effect of the annealing characteristics of MgO thin film, which is used as a protecting layer and known to play an important role to life time and lower the firing voltage in AC plasma displays, was investigated experimentally. MgO films were deposited on glass substrates by an electron beam evaporation method and annealed at different temperatures with varying heat treatment time. The characteristics of the crystallization and surface morphology of MgO films were changed by various annealing conditions, confirmed with X-ray diffraction method and scanning and transmission electron microscopes (SEM & TEM). With increasing annealing time and higher temperature, the intensity of the X-ray diffraction peak and the crystalline grain size of MgO increases. With the change of crystallinity and the decrease in grain boundary area, it is considered that the characteristics of firing voltage and life time of the plasma display panel can be improved with appropriate annealing process.
Preparation of The Double-Sided YBa2Cu3O7-δ Thin Film by Hot-Wall Type Mocvd
Authors: Ito Y. , Iwata M. , Yoshida Y. , Takai Y. , Hirabayashi I. 
Published: April 2011

ABSTRACTA hot-wall type metal organic chemical vapor deposition (MOCVD) apparatus has been developed for the deposition of the YBa2Cu3O7-δ (YBCO) films using liquid metal organic sources on arbitrary shaped substrates. By improving the reactor shape and gas flow of the source materials, we succeeded in fabricating the double-sided YBCO films for electronic and microwave devices and the YBCO-coated conductor on oxide fiber for power applications. Tc(zero)'s of the YBCO film on both sides of the LaAlO3 (100) substrate were 90K and 86K, respectively. The films on the facet of the single crystalline SrTiO3 fiber showed the single phase c-axis orientation with biaxially alignment in the a / b plane.
The (001) Surface of Fe3O4 Grown Epitaxially on MgO and Characterized by Scanning Tunneling Microscopy.
Authors: Gaines J. M. , Kohlhepp J. T. , van Eemeren J.T.W.M. , Elfrink R.J.G. , Roozeboom F. , de Jonge W.J.M. 
Published: April 2011

AbstractSpinel Fe3O4 contains two sites for iron: tetrahedrally coordinated sites containing Fe3+ ions and octahedrally coordinated sites containing a mixture of Fe2+ and Fe3+ ions. Scanning tunneling microscopy performed on the (001) surface of Fe3O4, grown epitaxially on MgO, shows localized charge density at the tetrahedral sites. The images show that the p(1×1) surface reconstruction (also observed during molecular beam epitaxy of Fe3O4) is produced by a displacement of the two tetrahedrally coordinated Fe ions on the unit cell surface from their bulk positions toward each other. The octahedral Fe ions are imaged as extended rows of charge density, with no resolution of atom-size features along the rows. This slight corrugation of electron charge density along the octahedral sites is consistent with the original conjectures explaining the high electrical conductivity in bulk Fe3O4: electrons move by hopping between the Fe3+ and Fe2+ atoms along the octahedral rows of Fe ions.
Vacancy Related Defects in La0.5Sr0.5CoO3-δ Thin Films
Authors: Keeble D. J. , Madhukar S. , Nielsen B. , Krishnan A. , Asoka-Kumar P. , Aggarwal S. , Ramesh R. , Poindexter E. H. 
Published: April 2011

ABSTRACTLaser ablated La0.5Sr0.5CoO3-δ thin films have been studied by Doppler-broademng-detected positron annihilation using a variable-energy positron beam. The oxygen partial pressure during cooling from the growth temperature was altered through the range 760 torr to 10−5 torr to change the oxygen non-stoichiometry of the films.The measured Doppler broadened lineshape parameter S was found to increase with increasing oxygen nonstoichiometry. For films cooled with an oxygen partial pressure of ≤ 10−4 Torr positron trapping to monovacancy type defects is infered. It is proposed that Sr ion oxygen vacancy complexes are likely trapping sites.For the film cooled in 10−5 torr oxygen the magnitude of the increase in S, with respect to that measured from the film cooled in 760 Torr oxygen, showed positron trapping to vacancy cluster defects is occuring.
Pulsed Laser Deposition of (Sr1-xCa)RuO3and Sr(Ru1-xTix)O3Thin Films by Sequential Multilayer Process
Authors: Mffiville L. , Antognazza L. , Char K. , Geballe T. H. 
Published: April 2011

ABSTRACTWe report on the growth and properties of (Sr1-xCax)Ru03and Sr(Ru1-xTix)O3thin films obtained by pulsed laser deposition. A sequential deposition of sub-monolayers from SrTiO3and CaRuO3end members has been successfully used to substitute Ca- and Ti- in the SrRuO3perovskite structure. Magnetization measurements as well as transport properties exhibit very different behavior for each type of substitution. In the case of Ca- substituted samples, the resistivity remains metallic and is consistent with the expected behavior for intermediate compositions. A progressive reduction of the Curie temperature with higher doping is reported. In the case of Ti- substituted samples, we observe a stronger reduction of the Curie temperature and remanent magnetization with increasing Ti substitution. Resistivity as a function of temperature shows a crossover from metallic to semiconducting behavior with variable range hopping process for a high level of Ti doping and points out the clear differences between the two substitutions sites. In both cases, the observed reduction of the magnetization with increasing doping concentration can be well described by assuming a random distribution of substituted sites in the perovskite structure.
Oxide Quantum Structures for Future Electro-Photonics
Authors: Kawasaki M. , Ohtomo A. , Tsuchiya R. , Nishino J. , Koinuma H. 
Published: April 2011

ABSTRACTWe show our recent development on the epitaxial growth of oxide thin films by laser molecular beam epitaxy directed towards a possible new field of electro-photonics based on metal-oxide quantum structures. Examples of quantum structures include superlattices and tunnel junctions (2-dimensional), superconducting quantum wire arrays (1-dimensional), and quantum dots for photonic application (O-dimensional). For fabricating such structures, it is vitally important to prepare the substrate surface and to understand the growth dynamics. Such electro-phptonic functions as Josephson effect in high Tc tunnel junctions and excitonic UV-laser operation at room temperature in self-organized hexagonal nanocrystal ZnO films are presented.
Characteristics of Y2O3 films on Si(100) by ionized cluster beam deposition
Authors: Cho M. H. , Whangbo S. W. , Whang C. N. , Choi S. C. , Kang S. B. , Lee S. I. , Lee M. Y. 
Published: April 2011

ABSTRACTIn this study, the Y2O3 films on p-type Si(100) have been fabricated by UHV reactive ionized cluster beam deposition(r-ICB) systems. The crystallinity of the films was investigated by glancing X-ray diffraction(GXRD) and in-situ reflection of high energy electron diffraction(RHEED) analyses. The results show that the preferentially oriented crystallinity of the films was increased with acceleration voltages as well as substrate temperatures. Especially, at the substrate temperature of 700 °C and the acceleration voltage of 5kV, the Y2O3 films grow epitaxially in direction of Y2O3(110)//Si(100). The characteristics of Al/Y2O3/Si MIS structure were obtained by C-V, and I-V measurements. The breakdown field strength of the epitaxially grown films increases up to 2MV/cm without any interface silicon oxide layer, and the dielectric constant is found to be ε=15.6. these results demonstrated that the yttrium oxide films have potential application to the gate insulator of the future VLSI/ULSI devices.