Fabrication Laboratory

In the OPT Fabrication Laboratory, different elements (predominantly crystals) that can be used for x-ray beamlines, mainly synchrotron radiation beamlines, are prepared and/or improved. The lab is supplied with the following equipment: a crystal cutter, three polishers/lappers , chemical hoods, and control equipment. The lab has also access to other equipment like grinders, polishers, a core drill press and ultrasonic mill that are operated by the Argonne National Lab Central Optics Shop. In1998, the lab manufactured over a total of 120 new crystal elements and improved or modified about 20 others. Requests for new elements included, for example, cryo-monochromators, interferometers and analyzers. Improvements and/or modifications of existing crystals consisted of operations such as reshaping, repolishing and re-etching.

Crystal Cutter (Meyer-Burger TS121)

The crystal cutter is a Meyer-Burger TS121 O.D. diamond saw. It is CNC controlled and can accommodate diamond blades up to 16" in diameter. The object cut (e.g., ingot or crystal) can be moved along three mutually orthogonal directions (with travels up to 500 mm, 320 mm, and 160 mm in the X, Y, and Z directions, respectively) and is mounted on a rotary table and/or a large sine bar.

Polishers/Lappers

The Fabrication Laboratory utilizes the following lappers/polishers:

  • STRASBAUGH 6DF-1 #1

    This machine is set up for coarse lapping of optical components (up to 12" dia). Slurries containing lapping compounds with grains between 9 and 50 micrometers are used.
  • HYPREZ Lapper/Polisher

    This machine is used for fine lapping of optical components (up to 12" dia.) with slurries containing 6 micrometer lapping grains.
  • STRASBAUGH 6DF-1 #2

    This machine is set up for polishing of optical components (up to 12" dia) with slurries containing polishing grains between 0.25 and 3 micrometers.

Other Equipment

  • Two midsize grinders: grinding up to 10" travel
  • Blanchard precise grinder: grinding up 24" diam.
  • Some polishers (Strabaught, Elgin)
  • Core drill press: drilling holes in silcon up to 1.5" diam. & 3" deep
  • Ultrasound mill: depth machining up to 0.75"

Control Equipment

The Fabrication Laboratory is equiped with its own interferometer for monitoring the quality of the optics during the fabrication process. The interferometer consists of a FISBA Optik MicroPhase, which is a compact modular-type instrument. The interometer measuring range is 10 Lambda, and its accuracy is about l/10 lambda. Optics requiring more accurate measurements are sent to the Metorology Laboratory.

 

X-ray Laboratory

The OPT X-ray Laboratory provides opportunities to orient and test single crystals, to characterize multi- or single layers deposited on different substrates, and to perform experiments that are possible with the use of conventional x-ray generators. In particular, the lab supports operation of the Fabrication Laboratory.

The laboratory is equipped with two 2 kW x-ray generators with conventional tubes and one 18 kW rotating anode generator. Single- and double-axis diffractometers are installed at the Rigaku conventional generator. A Laue camera, another double-crystal setup and the space for experiments are available at the Spellman conventional generator. Two big diffractometers, the so-called Topography Test Unit (TTU) and a triple-axis diffractometer are operated at the Rigaku rotating anode generator. In1998, topographic tests of about 80 silicon crystals (monochromators and analyzers already manufactured, and ingots to be used for fabrication), 15 diamond samples, and 10 crystals of other types (germanium, silicon carbide, sapphire), and measured reflectivity of 40 multi- or single layers were performed in total. These types of tests were carried out using the TTU and the triple-axis diffractometer. Other available equipment was employed for numerous tests, predominantly of single crystals. For example, the double-crystal diffractometer was utilized for testing interferometers, and the Spellman generator was used for investigations of some archaeological samples.

Rigaku Conventional Generator and Associated Equipment The generator produces x-rays in conventional tubes (typical targets used - Cu and Mo) of maximum power 2 to 2.4 kW. Two horizontal, point focus beams are available at which single- and double-axis diffractometers are installed. The single-axis diffractometer is used for crystallographic orientation of ingots and other (pre) cut crystals, whereas the double-axis diffractometer is used to make computer-controlled precise measurements of rocking curves.

Spellman Conventional Generator and Associated Equipment X-rays are produced in conventional tubes (typical targets used - Cu and Mo) of maximum power 2 to 2.4 kW. Two horizontal, point focus beams are available.

The beam emerging from the left port can be transported to an 8 ft x 9 ft x 8 ft enclosure attached to the generator tower enclosure and can be utilized for custom-design experiments. In the past, this beam was employed for testing large-size x-ray equipment and for investigation of the chemical composition of some archaeological samples. The beam from the other port is shared by two types of experiments. A Laue camera may be installed just next to the beam port, and a pattern of backscattered reflections from a crystal can be examined. When the Laue camera is removed, the primary beam can be transported through a long vacuum tube to a separate enclosure. This additional chamber is primarily used for double-crystal reflection experiments requiring highly collimated primary beams.

Rigaku X-Ray GeneratorRigaku Rotating Anode Generator and Associated Equipment This second Rigaku x-ray generator is a rotating-anode-type generator with a maximum power of 18 kW. Targets made of copper or molybdenum can be mounted. Two horizontal beamlines (point focus) are available from two different ports. The beam from the right port is employed for work with a triple-axis diffractometer. This instrument can be used for specular and diffuse scattering measurements, as well as for crystallographic work that requires a four-circle goniometer.

The beam from the left port is transported in a vacuum tube to another enclosure, which accommodates a double-crystal diffractometer called the Topography Test Unit (S. Krasnicki, Rev.Sci.Instrum. 67 (9), September 1996). Highly collimated, monochromatic beams of the 80 x 90 mm footprint that can be obtained from asymmetrically cut monochromators enable topographic testing of big samples (typically 4" dia.).