Technology

Description

Lithography

The facility is fully equipped to perform standard lithography using various mask and photo resist technologies. Mylar film masks are used for most processing needs. Chrome masks are used for microscale features below 5 µm in size. Both negative and positive photoresists are available, as well as photosensitive biomaterials developed in house for specific applications.

Soft lithography

Soft lithography is a new technique that is based on the utilization of elastomeric stamps to create microstructures and/or microdevices. The technique is especially well-suited for biological applications because it can be applied to biologically compatible surfaces and most of the processing can be performed in a regular laboratory without cleanroom needs (except the manufacturing of the master).

Rapid prototyping

Many of the biologically relevant applications of BioMEMS require a quick turnaround time and inexpensive processing for testing of initial idea(s). The mylar film mask technique provides an excellent alternative to conventional photolithography for such applications, whereby an actual microdevice can be prototyped within 24 hours for a cost of approximately $100 for the transparency mask and cleanroom supplies. For even faster prototyping, a laser cutting tool can cut thin films of PDMS with 50 mm feature size directly from a CAD design.

Surface engineering

An armamentarium of different surface chemistry approaches are available including functionalized self-assembled monolayers, immobilization techniques for antibodies and aptamers, cell micropatterning techniques, and surface oxidation and plasma treatment.

Optical Profilometry

As microfluidic designs become more advanced, detailed geometric features such as channel height, surface roughness, and the slopes of side walls can have a significant impact on the performance of the device. Optical profilometry enables precise characterization of these features across an entire microfluidic device.

Surface characterization

One optical and one mechanical profilometer, in addition to a metallurgical microscopy system are available for the characterization of micromachined surfaces prior to use and for quality control. Through the use of equipment funds, we plan to expand this important function to surface characterization.

Bonding

Bonding of two microfabricated surfaces is essential for the creation of microfluidic systems and devices, and various capabilities to bond glass, PDMS, and silicon surfaces are available.

Deep reactive ion etching

Deep plasma etching enables the fabrication of high aspect ratio (1:10) microstructures. This capability is available and routinely accesses through our collaboration with the Microsystems Technology Laboratories at MIT.

Microfluidics

Many of the devices used in the BMRC are based on microfluidics. A broad range of tools are available to build and test microfluidic chips including micro-connectors, pumps, various pipes and lines, etc.

Macro-to-micro coupling

Automated blood and fluid handling systems are developed to integrate the sample with the microfluidic chips. These approaches developed within BMRC are generic and used by multiple projects and collaborators.

Hot embossing

Many of the microfluidic circuits require the use of plastics such as polymethylmethacrylate (PMMA), polystyrene (PS), or polycarbonate (PC). Hot embossing is available to manufacture plastic microchips.

Microvalves and actuators

The ability to control the flow of analytic reagents and manipulate particles on the micro-scale is critical to the implementation of many biological applications. A number of actuation systems are available including dielectrephoretic traps, micro-bubble actuation schemes, membrane based micro-valve approaches.

Metal Deposition

The integration of sensors and actuators into microfluidic systems greatly increases the range of applications. A physical vapor deposition system, combined with standard lithography techniques, enables the precise patterning of metal on silicon and glass substrates.

Ultra-Rapid Prototyping

Reducing the time from concept to implementation of microfluidic devices can dramatically increase the speed of prototyping. A laser cutting tool allows the cutting of precise patterns in sheets of PDMS, Plexiglas, and other plastics and polymers.

E-beam evaporation

The deposition of thick metal layers is essential for the integration of many electrodes and sensors onto microfabricated chips. An E-beam evaporation system is used for silicon, glass, and plastic substrates.

Computational packages

Understanding of the physical, chemical and biological interactions at the microscale is a sine qua non condition for success in bio-micro-systems research. Various simulation packages are available including CFDR (see letter of collaboration) and COMSOL. CFDR is a numerical multi-physics solver and a visualization tool module for simulations in micro-systems.