Vijayakumar R. Dhuler

Smart MEMS: flip chip integration of MEMS and electronics

This paper will describe a new approach to the integration of electronics with MEMS, or Smart MEMS. Flip chip solder bumping of integrated circuits is routinely used for packaging purposes and has now been extended to the placement of electronics in close proximity to MEMS devices. The flip chip approach separates the fabrication of the MEMS and electronic devices, allowing both the ICs and MEMS to be fabricated of many different substrate materials, not just single crystal silicon. The close proximity of the electronics to the MEMS devices is very desirable to improve signal to noise performance, and provide higher levels of systems integration. This new approach provides batch fabrication capability as opposed to the serial hybrid approach, without having to fabricate the electronics and MEMS on the same chip. Results on the attachment of surface micromachined structures to glass and silicon substrates will be reported.

In-package active fiber optic micro-aligner

We describe and demonstrate what we believe is the first 3- axis MEMS active fiber optic micro-aligner, which will allow for in-package alignment of fiber optic and micro-optic components. The micro-aligner is a wafer level fabricated device, based on a combination of silicon micromachining and LIGA technology. The electrically controllable actuators demonstrate the high force and displacement necessary to overcome fiber optic, counterforce springs, friction, and wirebonds to perform in-package alignment of a fiber optic. We have demonstrated movement of > 20 microns in all three axes in an in-package configuration. The first prototype device are currently small enough (4 X 4 X 0.5 mm3) to fit into a standard 14 pin butterfly package. We will show that future devices with the same forces and displacements can be made smaller than 1 X 1 X 0.5 mm3 thus allowing for multiple single mode fiber optic attachments inside a standard opto-electronic package.

MEMS infrastructure: the multiuser MEMS processes (MUMPs)

In order to help provide access to advanced MEMS technologies, and lower the barriers for both industry and academia, MCNC, and ARPA have developed a program which works to provide users with access to both MEMS processes and advanced integration techniques. The two distinct aspects of this program, the MUMPs and Smart MEMS, will be described in this paper. The multi-user MEMS processes (MUMPs) is an ARPA-supported program created to provide inexpensive access to MEMS technology in a multi-user environment. MUMPs is a proof-of-concept and educational tool to aid the developemnt of MEMS in the domestic community. MUMPs technologies currently include a 3-layer polysilicon surface micromachining process and LIGA processes that provide reasonable design flexibility within set guidelines. Smart MEMS is the development of advanced electronics integration techniques for MEMS through the application of flip chip technology.

Characterization study of flip chip integration for MEMS

This paper will describe the characterization study conducted to determine the suitability of Flip Chip integration of electronics with MEMS. Successful demonstration of the operation of various MEMS devices in conjunction with Flip Chip is reported. Flip chip solder bumping of integrated circuits is routinely used for packaging purposes and has now been extended to the placement of electronics in close proximity to MEMS devices. The flip chip approach separates the fabrication of the MEMS and electronic devices, allowing both the ICs and MEMS to be fabricated of many different substrate materials, not just single crystal silicon. The close proximity of the electronics to the MEMS devices is very desirable to improve signal to noise performance, and provide higher levels of systems integration. This new approach provides batch fabrication capability as opposed to the serial hybrid approach, without having to fabricate the electronics and MEMS on the same chip. Results on the characterization study of attachment of surface and bulk micromachined structures to glass and silicon substrates is reported.

Integration of MUMPS and electronics for system prototyping

In order to create true Smart MEMS systems, the integration of electronics with the MEMS devices is essential. There are currently three methods of integration available: monolithic integration, flip chip attachment and hybrid assembly. The use of flip chip attachment for Smart MEMS has previously been described, and is now available as part of the ARPA- supported MEMS infrastructure programs MUMPs and TechNet. This paper will describe the electromechanical control system chip and the method of using it in conjunction with MUMPs to develop Smart MEMS prototypes.