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Latest results from the SEMATECH Berkeley extreme ultraviolet microfield exposure tool

Description: Microfield exposure tools (METs) continue to play a dominant role in the development of extreme ultraviolet (EUV) resists. One of these tools is the 0.3 numerical aperture SEMATECH Berkeley MET operating as a resist and mask test center. Here they present an update on the tool summarizing some of the latest test and characterization results. they provide an update on the long-term aberration stability of the tool and present line-space imaging in chemically amplified photoresist down to the 20-nm half-pitch level. Although resist development has shown substantial progress in the area of resolution, line-edge-roughness (LER) remains a significant concern. Here we present a summary of recent LER performance results and consider the effect of mask contributors to the LER observed from the SEMATECH Berkeley microfield tool.
Date: September 2, 2008
Creator: Naulleau, Patrick; Anderson, Christopher N.; Chiu, Jerrin; Dean, Kim; Denham, Paul; George, Simi et al.
Partner: UNT Libraries Government Documents Department

How to Take Better Photographs: Control Quality by Controlling the Camera

Description: In this Tech Talk presentation, the authors demonstrate simple ways to improve a photograph by making use of camera controls and by considering location, lighting, and composition. The authors will introduce basic information about using manual camera settings to control aperture, shutter speed, and ISO, and the authors will discuss specific "shooting" situations such as portraits, group photos, and events.
Date: July 27, 2011
Creator: Jones, Jerrell & Hall, Nathan
Partner: UNT Libraries

Lithographic characterization of low-order aberrations in a 0.3-NAEUV microfield exposure tool

Description: Although tremendous progress has been made in the crucial area of fabrication of extreme ultraviolet (EUV) projection optics, the realization diffraction-limited high numerical aperture (NA) optics (above 0.2 NA) remains a concern. The highest NA EUV optics available to date are the 0.3-NA Microfield Exposure Tool (MET) optics used in an experimental exposure station at Lawrence Berkeley National Laboratory [1] and commercial METs [2] at Intel and SEMATECH-North. Even though these optics have been interferometrically demonstrated to achieve diffraction-limited wavefront quality, the question remains as to whether or not such performance levels can be maintained after installation of the optics into the exposure tool. Printing-based quantitative aberration measurements provide a convenient mechanism for the characterization of the optic wavefront error in the actual lithography tool. We present the lithographic measurement of low-order aberrations in the Berkeley MET tool, including a quantitative measurement of astigmatism and spherical error and a qualitative measurement of coma. The lithographic results are directly compared to interferometry results obtained from the same optic. Measurements of the Berkeley MET indicate either an alignment drift or errors in the interferometry on the order of 0.5 to 1 nm.
Date: March 1, 2006
Creator: Naulleau, Patrick; Cain, Jason; Dean, Kim & Goldberg, Kenneth A.
Partner: UNT Libraries Government Documents Department

Techniques for Identifying and Measuring High Order Modes in RF Cavities

Description: We report on a number of techniques which can be used to unravel the higher-order-mode spectrum of an RF cavity. Most of these techniques involve the application of basic symmetry principles and require for their application only that the cavity exhibit some basic symmetry, possibly broken by the presence of couplers, apertures, etc., which permits a classification of these modes in terms of some property characterized by that symmetry, e.g., multipolarity for a cavity which is basically a figure of revolution. Several examples of the application of these techniques are given.
Date: May 1, 1997
Creator: Goldberg, D.A. & Rimmer, R.A.
Partner: UNT Libraries Government Documents Department

Orbit, optics and chromaticity correction for PS2 negative momentum compaction lattices

Description: The effect of magnet misalignments in the beam orbit and linear optics functions are reviewed and correction schemes are applied to the negative momentum compaction lattice of PS2. Chromaticity correction schemes are also proposed and tested with respect to off-momentum optics properties. The impact of the correction schemes in the dynamic aperture of the lattice is finally evaluated.
Date: May 4, 2009
Creator: Papaphilippou,Y.; Barranco, J.; Bartmann, W.; Benedikt, M.; Carli, C.; de Maria, R. et al.
Partner: UNT Libraries Government Documents Department

Comparison of Tevatron C0 and F0 Lambertson beam impedance

Description: Both the longitudinal and transverse beam impedance measurements for the Tevatron C0 and F0 lambertsons are presented. The C0 lambertsons were designed for circulating beam to travel through the 1 inch high by 6 inch wide field region. In the F0 lambertsons, circulating beam passes through the 2.5 inch high by 4 in ch wide field free region. The more recently designed F0 lambertsons have significantly less impedance than the older C0 lambertsons. Transverse impedance scales as one over the diameter of the aperture cubed. The three C0 style lambertsons were recently removed from the Tevatron. Four of the F0 lambertsons remain. Nine of the F0 style lambertsons are in the Main Injector and three more are required for Numi.
Date: April 11, 2003
Creator: Fellenz, James L Crisp and Brian
Partner: UNT Libraries Government Documents Department

Aperture limitations for 2nd generation Nb3Sn LHC IR quadrupoles

Description: One of the straightforward ways towards the higher luminosity in the LHC is a replacement of the present 70-mm NbTi quadrupoles with Nb{sub 3}Sn quadrupoles which would provide the same field gradient but in a larger aperture. Conceptual designs of such quadrupoles with 90 mm aperture have been developed and studied. This paper discusses the possibilities and limitations of increasing the aperture of Nb{sub 3}Sn low-beta quadrupoles for a LHC luminosity upgrade up to 110 mm.
Date: June 2, 2003
Creator: Zlobin, Alexander V.; Kashikhin, Vadim V. & Strait, James B.
Partner: UNT Libraries Government Documents Department

Coupling Through Tortuous Path Narrow Slot Apertures into Complex Cavitivies

Description: A hybrid FEM/MoM model has been implemented to compute the coupling of fields into a cavity through narrow slot apertures having depth. The model utilizes the slot model of Warne and Chen [23]-[29] which takes into account the depth of the slot, wall losses, and inhomogeneous dielectrics in the slot region. The cavity interior is modeled with the mixed-order, covariant-projection hexahedral elements of Crowley [32]. Results are given showing the accuracy and generality of the method for modeling geometrically complex slot-cavity combinations.
Date: July 26, 1999
Creator: Jedlicka, Russell P.; Castillo, Steven P. & Warne, Larry K.
Partner: UNT Libraries Government Documents Department

PDII- Additional discussion of the dynamic aperture

Description: This note is in the nature of an addition to the dynamic aperture calculations found in the report on the Proton Driver, FERMILAB-TM-2169. A extensive discussion of the Proton Driver lattice, as well as the nomenclature used to describe it can be found in TM-2169. Basically the proposed lattice is a racetrack design with the two arcs joined by two long straight sections. The straight sections are dispersion free. Tracking studies were undertaken with the objective of computing the dynamic aperture for the lattice and some of the results have been incorporated into TM-2169. This note is a more extensive report of those calculations.
Date: July 23, 2002
Creator: Gelfand, Norman M.
Partner: UNT Libraries Government Documents Department

Optimization Of Chromaticity Compensation And Dynamic Aperture In MEIC Collider Rings

Description: The conceptual design of the Medium-energy Electron-Ion Collider (MEIC) at Jefferson Lab relies on an ultra-small beta-star to achieve high luminosities of up to 10{sup 34} cm{sup -2} s{sup -1}. A low-beta insertion for interaction regions unavoidably induces large chromatic effects that demand a proper compensation. The present approach of chromatic compensation in the MEIC collider rings is based on a local correction scheme using two symmetric chromatic compensation blocks that includes families of sextupoles, and are placed in a beam extension area on both sides of a collision point. It can simultaneously compensate the first order chromaticity and chromatic beam smear at the IP without inducing significant second order aberrations. In this paper, we investigate both the momentum acceptance and dynamic aperture in the MEIC ion collider ring by considering the aberration effects up to the third order, such as amplitude dependent tune shift. We also explore the compensation of the third order effects by introducing families of octupoles in the extended beam area.
Date: July 1, 2012
Creator: Fanglei Lin, Yaroslav Derbenev, Vasiliy Morozov, Yuhong Zhang, Kevin Beard
Partner: UNT Libraries Government Documents Department

The HIBEAM Manual

Description: HIBEAM is a 2 1/2D particle-in-cell (PIC) simulation code developed in the late 1990's in the Heavy-Ion Fusion research program at Lawrence Berkeley National Laboratory. The major purpose of HIBEAM is to simulate the transverse (i.e., X-Y) dynamics of a space-charge-dominated, non-relativistic heavy-ion beam being transported in a static accelerator focusing lattice. HIBEAM has been used to study beam combining systems, effective dynamic apertures in electrostatic quadrupole lattices, and emittance growth due to transverse misalignments. At present, HIBEAM runs on the CRAY vector machines (C90 and J90's) at NERSC, although it would be relatively simple to port the code to UNIX workstations so long as IMSL math routines were available.
Date: February 1, 2000
Creator: Fawley, William M.
Partner: UNT Libraries Government Documents Department

Stability of non-linear integrable accelerator

Description: The stability of non-linear Integrable Optics Test Accelerator (IOTA) model developed in [1] was tested. The area of the stable region in transverse coordinates and the maximum attainable tune spread were found as a function of non-linear lens strength. Particle loss as a function of turn number was analyzed to determine whether a dynamic aperture limitation present in the system. The system was also tested with sextupoles included in the machine for chromaticity compensation. A method of evaluation of the beam size in the linear part of the accelerator was proposed.
Date: September 1, 2011
Creator: Batalov, I.; /Moscow, MIPT; Valishev, A. & /Fermilab
Partner: UNT Libraries Government Documents Department

Nb3Sn Magnets for a Muon Collider

Description: High field dipole and quadrupole magnet designs with racetrack coils are investigated. The design option is particularly attractive for a muon collider dipole magnet using the Nb{sub 3}Sn superconductor. A conceptual design of {approx} 15 T single aperture dipole magnet is presented where the coils maintain a simple 2-d structure through the ends. The use of racetrack coils in quadrupole magnets is also discussed. It appears that the racetrack coils are less attractive for high gradient quadrupole magnets.
Date: June 20, 1998
Creator: Gupta, R.C.; Green, M.A.; Scanlan, R.M. & Palmer, R.
Partner: UNT Libraries Government Documents Department

Common Coil Magnet System for VLHC

Description: This paper introduces the common coil magnet system for the proposed very large hadron collider (VLHC). In this system, the high energy booster (HEB), the injector to VLHC, is integrated as the iron dominated low field aperture within the coldmass of the common coil magnet design introduced earlier. This 4-in-1 magnet concept for a 2-in-1 machine should provide a major cost reduction in building and operating VLHC. Moreover, the proposed design reduces the field quality problems associated with the large persistent currents in Nb{sub 3}Sn magnets. The paper also shows that the geometric field harmonics can be made small. In this preliminary magnetic design. the current dependence in harmonics is significant but not umnanageable.
Date: February 12, 1999
Creator: Gupta, R.
Partner: UNT Libraries Government Documents Department

Design and Fabrication of Racetrack Coil Accelerator Magnets

Description: Most accelerator magnets for applications in the field range up to 9 T utilize NbTi superconductor and a cosine theta coil design. For fields above 9 T, it is necessary to use Nb{sub 3}Sn or other strain sensitive materials, and other coil geometries that are more compatible with these materials must be considered. This paper describes their recent efforts to design a series of racetrack coil magnets that will provide experimental verification of this alternative magnet design for a dual aperture dipole magnet with the goal of reaching a field level of 15 T, will be described. The experimental program, which consists of a series of steps leading to a high field accelerator quality magnet, will be presented. Fabrication of a racetrack dipole magnet utilizing Nb{sub 3}Sn superconductor and a wind and react approach will be presented.
Date: November 11, 1998
Creator: Chow, K.; Dietderich, D.R.; Gourlay, S.A.; Gupta, R.; Harnden, W.; Lietzke, A. et al.
Partner: UNT Libraries Government Documents Department

DX magnet requirements for p-Au operation

Description: This document addresses the question of moving the DX magnets for p-Au operations. First the beam geometry is addressed. Next, the beam sizes are covered. Finally, a conclusion is presented.
Date: January 19, 2012
Creator: Tepikian, S.; Trbojevic&#44 & D.
Partner: UNT Libraries Government Documents Department

Yttrium Calcium Oxyborate for high average power frequency doubling and OPCPA

Description: Significant progress has been achieved recently in the growth of Yttrium Calcium Oxyborate (YCOB) crystals. Boules have been grown capable of producing large aperture nonlinear crystal plates suitable for high average power frequency conversion or optical parametric chirped pulse amplification (OPCPA). With a large aperture (5.5 cm x 8.5 cm) YCOB crystal we have demonstrated a record 227 W of 523.5nm light (22.7 J/pulse, 10 Hz, 14 ns). We have also demonstrated the applicability of YCOB for 1053 nm OPCPA.
Date: June 20, 2006
Creator: Liao, Z M; Jovanovic, I; Ebbers, C A; Bayramian, A; Schaffers, K; Caird, J et al.
Partner: UNT Libraries Government Documents Department

10-kJ Status and 100-kJ Future for NIF PetaWatt Technology

Description: We discuss the status of the NIF ARC, an 8-beam 10-kJ class high-energy petawatt laser, and the future upgrade path of this and similar systems to 100-kJ-class with coherent phasing of multiple apertures.
Date: July 2, 2007
Creator: Siders, C W; Crane, J K; Rushford, M C; Haefner, L C; Hernandez, J E; Dawson, J W et al.
Partner: UNT Libraries Government Documents Department

Evaluation of the Mathieu Function Series for Diffraction by a Slot

Description: Diffraction of a wave passing through a slot is a fundamental problem that has applications in many situations. A problem of current interest is the propagation of waves through obstacles such as buildings in an urban environment, where an entrance aperture could be approximated as a slot. Solutions for the diffracted fields of a slot have been obtained by exact eigenfunction expansions as well as various approximate and numerical methods. The eigenfunction solution, in terms of Mathieu functions, has been published by Stamnes and Eide [1] for a slot with several types of converging incident waves. Results of the eigenfunction solution are presented in [2] for slots up to 20 wavelengths in width and compared with Kirchho. and Debye approximations. We have attempted to duplicate the eigenfunction series results in [2]. Little information is given in [2] about the numerical issues in the evaluation. We encountered a number of problems in the evaluation of the Mathieu functions for wide slots that required modifications of the Mathieu function evaluation methods described in [3]. Results were obtained matching those for the largest slot of 20{lambda} in [2] and also for slots up to 40{lambda} width. The evaluation of the eigenfunction solution was checked against a 2D moment method solution and was in close agreement up to a slot width of 40{lambda}. The eigenfunction solution published by Stamnes and Eide is summarized below, followed by a discussion of the Mathieu function evaluation and problems encountered with large slot widths. Results are then presented for varying slot width and compared with the 2D moment method solutions. A moment method solution for a diverging wave incident on the gap between two square cylinders is also presented and compared with the fields in a slot representing the front aperture.
Date: June 15, 2005
Creator: Burke, G J & Pao, H Y
Partner: UNT Libraries Government Documents Department

Controlled-aperture wave-equation migration

Description: We present a controlled-aperture wave-equation migration method that no1 only can reduce migration artiracts due to limited recording aperlurcs and determine image weights to balance the efl'ects of limited-aperture illumination, but also can improve thc migration accuracy by reducing the slowness perturbations within thc controlled migration regions. The method consists of two steps: migration aperture scan and controlled-aperture migration. Migration apertures for a sparse distribution of shots arc determined using wave-equation migration, and those for the other shots are obtained by interpolation. During the final controlled-aperture niigration step, we can select a reference slowness in c;ontrollecl regions of the slowness model to reduce slowncss perturbations, and consequently increase the accuracy of wave-equation migration inel hods that makc use of reference slownesses. In addition, the computation in the space domain during wavefield downward continuation is needed to be conducted only within the controlled apertures and therefore, the computational cost of controlled-aperture migration step (without including migration aperture scan) is less than the corresponding uncontrolled-aperture migration. Finally, we can use the efficient split-step Fourier approach for migration-aperture scan, then use other, more accurate though more expensive, wave-equation migration methods to perform thc final controlled-apertio.ee migration to produce the most accurate image.
Date: January 1, 2003
Creator: Huang, L. (Lian-Jie); Fehler, Michael C.; Sun, H. (Hongchuan) & Li, Z. (Zhiming)
Partner: UNT Libraries Government Documents Department


Description: The LHC aperture imposes a tight tolerance of 20% on the maximum acceptable beta-beat in the machine. An accurate knowledge of the transfer functions for the individually powered insertion quadrupoles and techniques to compensate beta-beat are key prerequisites for successful operation with high intensity beams. They perform realistic simulations to identify quadrupole errors in LHC and explore possible ways of correction to minimize beta-beat below the 20% level.
Date: June 26, 2006
Partner: UNT Libraries Government Documents Department

Dynamic aperture evaluation for the RHIC 2009 polarized proton runs

Description: In this article we numerically evaluate the dynamic apertures of the proposed lattices for the coming Relativistic Heavy Ion Collider (RHIC) 2009 polarized proton (pp) 100 GeV and 250 GeV runs. One goal of this study is to find out the appropriate {beta}* for the coming 2009 pp runs. Another goal is to check the effect of second order chromaticity correction in the RHIC pp runs.
Date: May 4, 2009
Creator: Luo,Y.; Tepikain, S.; Bai, M.; Beebe-Wang, J.; Fischer, W.; Montag, c. et al.
Partner: UNT Libraries Government Documents Department

Status of LHC crab activity simulations and beam studies

Description: The LHC crab cavity program is advancing rapidly towards a first prototype which is anticipated to be tested during the early stages of the LHC phase I upgrade and commissioning. The general project status and some aspects related to crab optics, collimation, aperture constraints, impedances, noise effects. beam transparency and machine protection critical for a safe and robust operation of LHC beams with crab cavities are addressed here.
Date: May 4, 2009
Creator: Calaga,R.; Assman, R.; Barranco, J.; Barranco, J.; Calaga, R.; Caspers, F. et al.
Partner: UNT Libraries Government Documents Department

The SEMATECH Berkeley MET pushing EUV development beyond 22-nm half pitch

Description: Microfield exposure tools (METs) play a crucial role in the development of extreme ultraviolet (EUV) resists and masks, One of these tools is the SEMATECH Berkeley 0.3 numerical aperture (NA) MET, Using conventional illumination this tool is limited to approximately 22-nm half pitch resolution. However, resolution enhancement techniques have been used to push the patterning capabilities of this tool to half pitches of 18 nm and below, This resolution was achieved in a new imageable hard mask which also supports contact printing down to 22 nm with conventional illumination. Along with resolution, line-edge roughness is another crucial hurdle facing EUV resists, Much of the resist LER, however, can be attributed to the mask. We have shown that intenssionally aggressive mask cleaning on an older generation mask causes correlated LER in photoresist to increase from 3.4 nm to 4,0 nm, We have also shown that new generation EUV masks (100 pm of substrate roughness) can achieve correlated LER values of 1.1 nm, a 3x improvement over the correlated LER of older generation EUV masks (230 pm of substrate roughness), Finally, a 0.5-NA MET has been proposed that will address the needs of EUV development at the 16-nm node and beyond, The tool will support an ultimate resolution of 8 nm half-pitch and generalized printing using conventional illumination down to 12 nm half pitch.
Date: March 18, 2010
Creator: Naulleau, P.; Anderson, C. N.; Backlea-an, L.-M.; Chan, D.; Denham, P.; George, S. et al.
Partner: UNT Libraries Government Documents Department