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This letter reports the first replacement (Damascene) metal gate pMOSFETs fabricated with Ni/TaN, Co/TaN stacked electrode, where Ni or Co is in direct contact with the gate SiO/sub 2/, to adjust the electrode metal work function and TaN is used as the filling material for the gate electrode to avoid wet etching and CMP problems. The process is similar to the fabrication of traditional self-aligned polysilicon gate MOSFETs, except that in the back end (after the source/drain implants are activated) a few processing steps are added to replace the polysilicon with metal. Our data show that the Ni or Co/TaN gate electrode has the right work function for the pMOSFETs. The metal gate process can reduce the gate resistivity. Thermal stability of the stacked electrodes is studied and the result is reported in this paper. The damascene process flow bypasses high temperature steps (> 400/spl deg/C)critical for metal gate and hi k materials. This paper demonstrates that a low temperature anneal (300/spl deg/C) can improve the device performance. In this paper, the gate dielectrics is SiO/sub 2/.

Auger electron spectroscopy analyses of submicron features on semiconductor surfaces are routinely accompanied by analytical artifacts such as sample degradation and background contributions arising from electron beam scattering. Submicron analyses are commonly carried out at electron beam densities in excess of 1 A cm -2 and are especially damaging to silicon oxides. The evolution of oxide reduction is observed both as a loss of oxygen versus beam exposure and in a complementary growth of Si LVV and Si KLL elemental peaks. The O KLL signal intensity from a 1 μm 2 area of thermally grown oxide is found to decrease by 22% after exposure to a rastered 20 kV/10 nA beam for 10 min. Another aspect of submicron analysis is the contribution to survey spectra that originates when surrounding material is excited by backscattered electrons. Background contributions may dominate AES spectra even when the sample is flat and the probing beam is smaller than the feature of interest. Tungsten damascene contacts provide a useful platform for investigating this phenomenon in the absence of topography. Spectra have been collected from tungsten contacts of various sizes and the target and background contributions quantified. When a 0.25 μm diameter tungsten contact is probed with a narrow 20 kV beam, the W MNN signal intensity is determined to be only 70% of that emitted from a large tungsten structure. Target signal reduction coincides with increased signal contributions from the surrounding oxide.

The Christian and Missionary Alliance (C&MA) was founded in New York City in 1887 as two interdenominational parachurch organizations, the Christian Alliance and the Evangelical Missionary Alliance, by Albert Benjamin Simpson (1843–1919), a former Canadian Presbyterian minister. His purpose was to bring together people from all denominations, with a common bond of emphasizing holiness, faith, healing, and missionary vision — what he and others called “the higher Christian life.” Merged together as The Christian and Missionary Alliance in 1897, it eventually evolved into a denomination many decades later. Keywords: christian and missionary alliance (CM interdenominational parachurch organizations; CM bringing together people, from all denominations; Simpson, fourfold gospel, christ as “savior, sanctifier, healer …”; CM CM Wesleyan and Keswick holiness traditions; presbyterial and congregational concepts; C&MA periodical, the alliance life

Albert Benjamin Simpson was born in 1843 in Toronto, Canada. Graduating from Knox Seminary in Toronto, Simpson became a successful Presbyterian pastor in Hamilton, Ontario, Canada; Louisville, Kentucky; and New York City. In 1874 after reading the book The Higher Christian Life by W. E. Boardman, a leader in the Higher Life and Keswick holiness movements, he experienced what he identified as a sanctifying baptism of the Holy Spirit. Keywords: Simpson, A. B. (1843–1919); christian and missionary alliance (CM new interdenominational parachurch organization

Born in 1897 in Pennsylvania, Aiden Wilson Tozer was converted at the age of 17 by a lay preacher at a street meeting. He attended the Methodist Church and was baptized in Church of the Brethren before he became ordained with The Christian and Missionary Alliance (CM Indianapolis, Indiana; Chicago, Illinois; and Toronto, Ontario. A prolific writer, he became editor of Alliance Life for 13 years. He served as Vice President of the C&MA 1946–1950, but declined the presidency of the denomination. His writings and teachings have had an immense impact on the lives of thousands of Christians. His classic The Pursuit of God (1948), urging being passionate for God himself, has sold more than 1.5 million copies and been translated into 20 languages. It was chosen by Christianity Today readers as one of the top ten most spiritually influential books. Known for his incisive writing to issues of the times, more than 40 volumes of his writings and sermons have been published. The Divine Conquest (1950) and The Knowledge of the Holy (1961) also became classics. Keywords: Tozer, A. W. (1897–1963); CM vernacular literacy, bridge to national language of Spanish

The design and testing of an imaging band‐pass analyzer (BPA) consisting of two 90° spherical sectors operating in a magnetic‐field‐free region is described. Image electrons injected nearly parallel to one another and perpendicular to the first 90° sector are focused into an energy plane where electrons of desired energy are band‐pass filtered. A second 90° sector is used to recover the energy‐filtered image. With a 1‐mm aperture, energy resolution of 1% and spatial resolution of 0.01% of the main path radius are calculated and agree well with the test results over an image size of 12×12 mm2. The addition of this analyzer to our magnetic projection photoelectron microscope poses an additional technological problem in that the electrons are required to pass from a relatively high‐field area to a field‐free region without disruption of the image. Design considerations for a structure that abruptly terminates a magnetic field yet is transparent to image electrons are described.

The high-resolution Ca ${\mathit{L}}_{2,3}$ x-ray-absorption near-edge-structure (XANES) spectrum of a ${\mathrm{Bi}}_{2}$${\mathrm{Sr}}_{2}$${\mathrm{CaCu}}_{2}$${\mathrm{O}}_{8}$ single crystal has been measured by use of a magnetic-projection x-ray microscope probing a surface area of 200\ifmmode\times\else\texttimes\fi{}200 \ensuremath{\mu}${\mathrm{m}}^{2}$. The Ca ${\mathit{L}}_{2,3}$ XANES spectrum is analyzed by performing a multiple-scattering XANES calculation in real space and comparing the results with the spectrum of ${\mathrm{CaF}}_{2}$. Good agreement between the calculated and experimental crystal-field splitting ${\mathrm{\ensuremath{\Delta}}}_{\mathit{f}}$ of the Ca 3d final states is found and the splitting is shown to be smaller by 0.5 eV than in the initial state. The Ca 3d partial density of states is found to be close to the Fermi level in the initial state. The Ca-O(in plane) distance is shown to be a critical parameter associated with the shift of the Ca 3d states relative to the Fermi level; in particular, we have studied the effect of the out-of-plane dimpling mode of the in-plane oxygen atoms O(in plane) that will move the Ca 3d states on or off the Fermi level. This mode can therefore play a role in modulating the charge transfer between the two ${\mathrm{CuO}}_{2}$ planes separated by the Ca ions.

The magnetic projection photoelectron microscope performs imaging photoelectron and photoabsorption spectroscopy with a lateral resolution of the order of microns. We review practical experience accumulated in two months of synchrotron-based operations. Theoretical limitations and practical issues related to count rates, elemental and chemical contrast and extraneous noise are discussed. A comparison is made between our experience with retarding field analysis and a conceptual imaging band-pass analyzer. Recent observations from surface diffusion experiments are presented.

At the 65 nm node, silicide faces formidable challenges. Co is the current process of record for most integrated circuit manufacturers and thus becomes baseline silicide for 65 nm. However, Ni is the likely replacement. Both silicides are challenged to meet the requirements at the 65 nm node. This manuscript reviews the current CoSi2challenges (dopant interactions, Ge interactions, linewidth extendibility, impurity effects, agglomeration issues, etc). Ni consumes less Si but has its own challenges, including issues with contact leakage and thermal budget, excessive diffusion and oxidation, interactions with dopant and impurities. Both silicides have formation and stability issues in the presence of Ge. Additions of Ge increase the temperature at which a low resistance CoSi2is formed due to film segregation into CoSi2and Ge-rich Si-Ge grains. With Ni, additions of Ge decrease the temperature at which NiSi converts to a NiSi2, lead to agglomeration at a lower temperature and lead to germanosilicide formation.

As lithographic technology nodes advance beyond the 193 nm generation, the optical absorption of organic materials will require the use of thin layer imaging (TLI) techniques. Of the techniques under consideration, the use of ultra-thin resist (UTR) over a hardmask is the most desirable because of its simplicity and close similarity to standard single layer resist processes. Prior work has demonstrated that the UTR process is capable of pattern transfer to poly silicon device layers with as little as 1000 Angstrom of resist on flat wafers using 248 nm lithography. This was achieved with defect levels comparable to a conventional 5000 Angstrom resist process. In this work, we demonstrate 'proof of concept' by integrating the UTR process into the transistor gate module of a production device using 248 nm lithography. In doing so we focus on three key areas for manufacturability: inherent defectivity of UTR films, sensitivity of thin resist to topography, and quality of pattern transfer. We find that pinhole defects are of little concern in the UTR process after SEM review of defects on un-patterned UTR films. We show that the UTR process is sensitive to wafer topography, since it does not provide a completely planar surface over the underlying device features. Finally, we demonstrate that the UTR process is capable of reliable pattern transfer on a production device with defect levels comparable to the thicker baseline single layer resist process.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A photoelectron microscope operating with a retarding field analyzer has been used to exploit core level energy shifts due to band bending in order to directly image Fermi level variations on n- and p-type cleaved GaAs(110) surfaces. Fermi level maps resolved to better than 10 um indicate lateral variations in the surface Fermi level which are often quite abrupt. In agreement with earlier, lower resolution work [1], Fermi level topography is found to be highly correlated with surface roughness as characterized by SEM, optical microscope and stylus profi lometer. The largest defect derived pinnings encountered to date resut in the Fermi level lying 0.5 eV above the VBM for both n- and p-type GaAs. Low coverage In evaporations have the. effect of reducing Fermi level contrast as Fermi levels in formerly unpinned regions move into the gap.

A photoelectron microscope operating with a retarding field analyzer can exploit core level energy shifts in order to image Fermi‐level variations of semiconductor surfaces. Fermi‐level maps of cleaved n‐ and p‐type GaAs (110) resolved to better than 10 μm indicate lateral variations in the surface Fermi level which are often quite abrupt. In agreement with earlier, lower resolution work [J. M. Palau, E. Testemale, and L. Lassabatere, J. Vac. Sci. Technol. 19, 192 (1981)],1 Fermi‐level topography is found to be highly correlated with surface roughness as characterized by scanning electron microscope (SEM), optical microscope, and stylus profilometer. Defective fracture surfaces have two distinct characters within SEM resolution: linear defects (steps and ledges) that may extend over millimeters and smooth glassy areas. Both types of surface defects shift the Fermi level towards midgap. The largest defect derived pinnings encountered to date result in the Fermi level lying 0.5 eV above the valence‐band max...

The thermodynamic properties of the binary LiZn, LiCd and LiPb alloy systems were investigated in an organic solvent-based electrolyte at ambient temperature. Titration curves showed several intermediate phases existing in each lithium alloy system. There was a wide composition range in Li y Cd (1.5 ⩽ y ⩽ 3), which showed a very low equilibrium potential (below 60 mV) against pure lithium. There was a longer potential plateau in the LiPb system corresponding to Li y Pb (1 ⩽ y ⩽ 3) at about 450 mV against pure lithium. The preliminary charge-discharge and polarization results showed rather fast kinetics for Li y Zn (0.67 ⩽ y ⩽ 1), Li y Cd (1.5 y y Pb (1 y

In this paper we describe present and planned synchrotron-based X-ray lithography facilities at Stanford. We also present standard procedures used at the Stanford Synchrotron Radiation Laboratory (SSRL) for conducting experiments in lithography mask damage, device damage, and X-ray resist characterization.

We describe simple methods of soft X-ray dosimetry (1000–3000 eV) for synchrotron based X-ray lithography. These methods are generally applicable to other synchrotron installations and possibly to so-called “stand alone” X-ray sources. A double crystal monochromator of synthetic multilayer crystals was used to obtain narrow band X-rays for energy-dependent measurements. The quantum efficiency of a stainless steel vacuum photocathode is shown to be well modeled by a simple power law, and its use in measuring the quantum efficiency of semiconductor diodes is described. The photocathode modeling is used in conjunction with the monochromator to demonstrate that resist sensitivity depends uniquely on absorbed dose density. The validity of the modeling is discussed, and the limitations of each type of detector are outlined. Suggestions are made for the application of these inexpensive detectors to real time source calibration in practical X-ray lithography equipment.

With a keyboard and supporting system developed at Cornell University, input methods used to identify ideographs are adaptations of well-known schemes; innovation is in the addition of automatic machine selection of ambiguously identified characters.The unique feature of the Cornell design is that a certain amount of intelligence has been built into the machine. This allows an operator to take advantage of the fact that about 60% of Chinese characters in text are paired with other characters to form two-syllable compounds or phrase words. In speech and writing these pairings eliminate about 95% of the ambiguities created by ambiguously identified syllables.

Boron nitride membranes (produced through chemical vapor deposition of diborane and ammonia) have been exposed to synchrotron radiation and have showed severe degradation in optical properties after absorbing doses on the order of 200kJ/cm3. Damage kinetics are described as well as measurements made to identify the damage mechanism. Preliminary results on associated mechanical damage are also presented. Boron nitride membranes (produced through the pyrolysis of borazine), silicon nitride and silicon membranes exposed and tested in the same manner showed no such degradation.

New Energy- Dependent Soft X -Ray Damage in MOS DevicesTung -Yi Chan, Henry Gaw, Daniel SeligsonIntel Corporation, SC2 -253065 Bowers AvenueSanta Clara, CA 95051Lawrence Pan, Paul L. King, and Piero PianettaStanford Synchrotron Radiation LaboratorySLAC /SSRL Bin 69, P.O. Box 4349Stanford, CA 94305AbstractAn energy- dependent soft x- ray- induced device damage has been discovered in MOSdevices fabricated using standard CMOS process. MOS devices were irradiated bymonochromatic x -rays in energy range just above and below the silicon K -edge (1.84keV). Photons below the K -edge is found to create more damage in the oxide andoxide /silicon interface than photons above the K -edge. This energy- dependent damageeffect is believed to be due to charge traps generated during device fabrication. Itis found that data for both n- and p -type devices lie along a universal curve ifnormalized threshold voltage shifts are plotted against absorbed dose in the oxide.The threshold voltage shift saturates when the absorbed dose in the oxide exceeds1.4X105 mJ /cm3, corresponding to 6 Mrad in the oxide.Using isochronal anneals, the trapped charge damage is found to recover with anactivation energy of 0.38 eV. A discrete radiation - induced damage state appears inthe low frequency C -V curve in a temperature range from 175 0C to 325 °C.I. IntroductionX -ray lithography is likely to displace optical lithography for semiconductordevice fabrication with dimensions < 0.4 um. Since x -ray photons have energies muchhigher than the band gap of silicon dioxide (about 9 eV), oxide damage caused by x-ray irradiation may be a serious concern in the application of x -ray lithography. Theeffects of x -rays and other forms of ionizing radiation on MOS structures have beenextensively studied for years [1 -4]. However, little work has been done to examinethe effect of varying the incident x -ray energy [5].In this paper, synchrotron x -ray sources were used to study the effect of x-rayenergy on radiation - induced device damage. X -ray photons studied have energy justabove and just below the silicon K -edge (1.84 keV). An energy- dependent soft

The optical and mechanical properties of boron nitride vapor deposited at 400 °C are shown to degrade when exposed to synchrotron radiation. The extent of the damage and the rate at which the damage occurs are similar to that first reported by Johnson et al. Transmission through membranes of boron nitride was measured in situ during exposure to x rays. Membranes darkened considerably with the transmission through a typical membrane falling from 50% to 20% after absorbing ∼250 kJ/cm3 of x rays. Changes in local film stress were measured with a simple cantilever technique. Films originally in tension (∼5E8 dyne/cm2) were found to become compressive after absorbing 300 kJ/cm3 of x rays. Both forms of damage responded well to annealing. Fourier transform infrared (FTIR) and near‐edge x‐ray absorption measurements were made to discern the structural differences between degraded and unexposed films. No significant structural changes were observed. Boron nitride films deposited at higher temperatures (600 °C) pr...