The J. Bennett Johnston, Sr., Center for Advanced Microstructures and Devices (CAMD), is named for the father of its congressional sponsor, Senator J. Bennett Johnston, Jr. of Louisiana.
CAMD is a synchrotron radiation research center at Louisiana State University in Baton Rouge. The mission of CAMD is to provide infrastructure for research and education in synchrotron-based science and technology. The facility was built with a $25-million grant from the U.S. Department of Energy and is currently operating with an annual state-provided budget of $4 million. The heart of the facility is a 1.5 GeV electron storage ring that was built exclusively to provide synchrotron radiation. Research in basic sciences and microfabrication is conducted by scientist and engineers from Louisiana universities, along with distinguished scientists from national and international institutions.
CAMD is the only state-funded synchrotron facility in the U.S. The spirit of the state appropriation is that LSU operate CAMD to benefit researchers in Louisiana in the areas of basic and applied sciences, particularly in developing technologies associated with microstructures and devices. By providing X-rays and equipment, as well as a principal part of the technological expertise, CAMD forms a nucleus for the development of strong programs in microfabrication, materials science and other targeted areas of scientific and technological exploration. This nucleus attracts scientists and engineers from Louisiana, across the U.S. and nations around the world. These individuals, along with the CAMD staff, provide the base of expertise necessary for technological development.
The centerpiece of the CAMD facility is a normal-conducting electron storage ring optimized for the production of soft X-rays. The machine is a low-energy-injected (200 MeV) Chasman-Green lattice designed to operate in the range of 1.2 - 1.5 GeV. The ring includes eight bending magnets with a radius of 2.928m. The dipole magnet chambers have two ports emitting > 70 mrad of synchrotron radiation each. Two straight sections are available for insertion devices, with one currently occupied by a superconducting wiggler.
Beam Energy (GeV) 1.3 / 1.5
Beam Current (mA) 300 / 150
Bending radius (meters) 2.928
Critical wavelength 7.45 / 4.85
Critical Energy (keV) 1.66 / 2.56
Beam half-life (hours) 9.5 / 6
Harmonic number 92
Radiative power (watts/mrad/mA) 0.014 / 0.024
Injection energy (MeV) 200
Natural emittance (m-rad) ~2x10-7
Electron-beam width (mm) ~0.6
Electron-beam height (mm) ~0.15
The wiggler consists of a 3-pole superconducting magnet with a maximum field of 7 T at the central pole and 1.55 T at the side poles. The horizontal deviation of the electron beam orbit at the central pole is equal to zero due to compensation of the beam trajectory realized by the superconducting magnet together with two normal conducting correctors at 0.6 T. Therefore, the magnetic-field strength of the central pole can be set to any value between zero and its maximum with the location of the source point fixed. This allows the critical wavelength to be tuned to a particular experiment.
CAMD's basic science research programs span a wide range of disciplines, including physics, chemistry, materials science and geology. Research thrusts include studies of thin-film magnetic alloys, catalysts, polymer/organic materials, and clay minerals, utilizing techniques including photoelectron spectroscopy, gas-phase photoionization and fluorescence spectroscopy, X-ray absorption spectroscopy, X-ray microspectroscopy and tomography.
PGM, 25-1600, eV, E/ΔE up to 10,000
3-m TGM, 15-350, eV, E/ΔE > 1,000
6-m TGM, 15-300 eV, E/ΔE > 2,000
3-m NIM, 2-50 eV, E/ΔE ~10,000 (high E); 50,000 (low E)
Experimental equipment includes angle-resolved two-axis hemispherical and/or ellipsoidal mirror electron-energy analyzers, and a high-resolution SCIENTA-200 analyzer.
XAFS, 1-14 keV, ΔE = 0.5 - 3 eV
XMP, 2-14 keV, ΔE = 1 - 3 eV (or white beam)
White Light, broad-band, 700 eV<E<15 keV
Equipment available at the X-ray beamlines includes a Kirkpatrick-Baez microfocusing mirror system, 4-circle Huber goniometer, 13-element Ge and single element Si (Li) detectors and a 50 micron resolution image plate system. An X-ray microtomography end station is installed at the white-light beamline.
The microfabrication program at CAMD is focusing on research, development and service in LIGA - a process combination of deep etch x-ray lithography with synchrotron radiation (LI), electro-forming (G German: Galvanoformung), and molding (A; German: Abformung). Close collaboration with groups form industry and research entities to develop processes, prototypes and MEMS devices is ongoing.
CAMD's microfabrication facility includes a total of four 'white light' beamlines
to conduct deep and ultra-deep X-ray lithography. Two beamlines are jointly operated
with the Institute for Micromanufacturing (IfM) at Louisiana Tech University in Ruston,
LA; One beamline is connected to the wiggler source.
Process and meterology equipment needed for this work is located within 2500 feet of Class 100 cleanroom inside the CAMD hall. CAMD's cleanroom provides LSU and other users with access to instrumentation required for the production of high aspect ratio processing, prototype development and MEMS (MicroElectroMechanical Systems) devices.
CAMD works closely with the faculty of Louisiana State University and Louisiana's other Ph.D. granting institutions to assist in the development of strong scientific and technological programs at the facility. This involvement covers a wide range of fields including chemistry, physics and all engineering disciplines.
Rather than operating as a traditional "user-facility", CAMD concentrates on developing strong long term collaborative efforts with external researchers. The Center has expanded its infrastructure and expertise through these collaborations, involving eminent national and international scientists from around the U.S., Germany, Japan and Brazil.
Richard L. Kurtz, CAMD Director
Phillip Sprunger, Scientific Director
Varshni Singh, Interim Director of Microfabrication
Craig Stevens, Assistant Director for Administration