Micro & Nano Fabrication

Instrumentation's Microfabrication Laboratory began ten years ago to assist the newly formed Accelerator Test Facility in the fabrication of microstructure arrays used to study novel acceleration mechanisms with a laser linac. The expertise gained in this area has since been used to manufacture specialized microstructures for many investigators in both academia and industry. On-going projects include infrared filter arrays for NASA, high resolution masks for e-beam deposition for Brandeis University, and industrial collaborations with Lockheed-Martin and Standard Microsystems to develop multi-axis accelerometers and improved versions of ink jet printer heads using high aspect ratio microfabrication.

Facilities

The Microfabrication Laboratory is equipped with all major apparatus used in microfabrication design, processing, and characterization. Visiting experimenters are encouraged to actively participate in the design process by learning the fundamental microfabrication processes such as anisotropic etching, plasma etching, and high aspect ratio lithography and then designing mask sets for the chosen method. Patterning steps take place in a Class-100 clean room equipped with a resist spinners, developing tanks, and etching stations. A Karl Suss MJB-3 mask aligner with both vacuum and hard contact modes is used for UV exposure and a Nikon optical microscope equipped with a custom-designed quantitative metrology measurement capability is used for analysis. An adjoining Class-l000 room contains oxidation furnaces for growing oxide layers on silicon wafers, a wet bench for anisotropic etching, and Plasmalab reactive ion etching and plasma enhanced chemical vapor deposition chambers. Completed microstructures can be examined with a high resolution AMRAY scanning electron microscope equipped with a LaB6 gun, and a Princeton Gamma Tech image and X-ray analysis system.

Current Research Efforts

CRADA with Lockheed Martin
Tactical Defense Systems MEMS technology is being used to develop a micro-accelerometer with 3 translation and 3 rotational measurement axes. The prototype uses high aspect ratio electroplated copper coils to levitate permanent magnets attached to a cubical proof mass.

High Aspect Ratio Deposition Masks
High aspect ratio lithography is being used to pattern a free-standing membrane that is placed in close contact with a nickel foil. Tungsten is deposited through the membrane openings to form a pattern on the foil that is examined with positron re-emission microscopy. This technique is being developed by Prof. Karl Canter of Brandeis University and BNL's Physics Dept. using a positron source located at BNL.

Infrared Filters for Infrared Interferometry in the l0-20 µm Range
In this effort, supported by NASA and performed in collaboration with Prof. Dieter Moeller of NJIT, free standing nickel filter arrays have been fabricated that selectively pass a narrow band of the infrared spectrum. Critical dimensions of the individual pattern holes are on the order of 2-3 µm.

High Speed X-ray Detector Array for Synchrotron Applications
High aspect ratio microfabrication with SU-8 photoresist is being used to fabricate both one-dimensional and two-dimensional position-sensitive detector arrays that have the potential to greatly increase the data collection rates of X-ray diffraction experiments at the NSLS and other synchrotrons.