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Microfabrication Applications Laboratory (MAL) is a research and
development laboratory at the University of Illinois at Chicago. It is
dedicated to the application of 'chip making' technology to improve
manufacturing methods for electromechanical, mechanical, chemical,
optical and multi-functional devices which are currently being
produced with less efficient techniques. The Laboratory is located on
the University of Illinois Chicago campus, just west of Chicago's
Loop. The MAL staff consists of 22 experienced researchers who are
also faculty members at UIC or UIUC, a full time laboratory manager,
and graduate students to assist in training new users. The laboratory
consists of a three thousand square foot clean room subdivided into
five bays and an equal device characterization area. Over two and a
half million dollars of equipment is installed in the UIC clean rooms.
Approximately one and a half million dollars of that amount has been
used to acquire new equipment at the cutting edge of microfabrication
technology. Unlike highly automated industrial production equipment,
equipment within the Center is flexible and multipurpose in function.
Cleanroom equipment has been carefully chosen to provide strong
capability within the thrust areas of BioMEMS,
High Frequency MEMS, MEMS Process Analysis and Development,
Microactuators/Microfluidics, and Microsensors/Miniature Analytical
Instruments. The clean room is divided into five bays to
provide work space for various functions including physical vapor
deposition (PVD), chemical vapor deposition (CVD), plasma enhanced CVD
(PECVD), wet and dry etching, surface characterization, and top and
bottom lithography.
The
lithography capabilities include a GCA MANN Model 3600F Pattern
Generator and GCA MANN Model 3696 Stepper fitted with a 10X reduction
lens. The pattern generator and stepper provide in house mask
fabrication which facilitates fast turn around when a design iteration
is needed. Standard positive and negative photoresist lithography
equipment are available. The MAL has a Karl Suss MJB3 Infrared aligner
for 'top to bottom' alignment of masks to silicon wafers. This
capability is especially useful when making sensors, membranes, and
three dimensional structures. MAL users have limited access to an OAI
Infrared aligner which can expose 4” wafers in the EECS
Undergraduate clean room.
The
PVD capabilities include a Varian e-beam system with planetaries for
2”, 3”, and 4” wafers; and a CVC system with 2 e-beam guns, 2
US-guns, a thermal source, and ion beam cleaning of the substrate.
The
LPCVD area consists of a refurbished four-stack furnace made by
Process Technology configured for silicon nitride, LTO, polysilicon,
and metal CVD. An important feature of the LPCVD system is that
variable stoichiometry films may be produced for optical waveguides.
The plasma enhanced CVD capabilities are provided by an ElectroTech
310 deposition station under computer control, which can provide films
of silicon nitride, silicon dioxide, silicon oxynitride, diamond like
diamond structure carbon and silicon carbide. There also is a four
stack Thermco furnace for oxidation and diffusion.
The
wet chemical etching facilities are comprehensive, consisting of an
assortment of anisotropic, isotropic and electrochemical etching
equipment for semiconductors, metals and dielectrics. Plasma etching
includes reactive ion etching and sputter etching in an ElectroTech
340 under computer control with six mass flow controllers to provide a
versatile array of gas compositions. A host of 'standard' etching
recipes utilized regularly by the semiconductor industry and
experimental recipes for non-standard materials will be employed.
The
inspection and characterization equipment include: Nikon optical
microscope with a Boeckler line measurement system, a BioRad FTIR
microscope, a Tencor P1 surface profiler, Gaertner ellipsometer, a
Digital Instruments Nanoscope III Scanning Tunneling and Atomic Force
Microscope with Electrochemical capability, and a Metricon Prism
coupler for the measurement of film thickness. The Tencor provides
large area surface topography measurements, with nanometer resolution
over scans of several centimeters. This device is extremely valuable
in characterizing the geometry of micromachined structures to an
accuracy of about 10 nm.
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