MicroAssembly Technologies (United States)

This was a collaborative effort between Lawrence Livermore National Security, LLC as manager and operator of Lawrence Livermore National Laboratory (LLNL) and MicroAssembly Technologies, Inc. (MAT) to develop spatial light modulators (SLM) based refocusing concentrators for telecom applications. MAT submitted a Phase I Small Business Technology Transfer (STTR) proposal, listing LLNL as a subcontractor, to the United States Air Force and subsequently received a grant award under solicitation AF03T009. This joint collaboration was to develop a spatial light modulator (SLM) based refocusing concentrator systems for telecom and other applications. One industry expert from AT&T estimated that such a device could increase gain by about 16x, or add about 12 dB to the link budget. The desired result of the Phase I effort was a successful feasibility demonstration of SLM based refocusing concentrators for telecom applications; and a study of system level architecture, micromirror array design and operating parameters for optimization. The task of delivery of a gold sputtering target to MAT was completed at the end of Phase II. The target was returned to LLNL at the end of the CRADA. LLNL also developed a system that could measure the gradient in the phase of the laser upon reflection from the MEMs with a much higher spatial resolution than achievable with a ShackHartmann approach.

MEMS packaging poses novel constraints as compared to conventional IC packaging, and accounts for up to 80% of the cost of the device. A new type of package is proposed, addressing the problems of hermeticity and die singulation, as well as an alternative means of MEMS-IC integration. An organic-free, metal-to-metal bond process enables hermetic sealing at low temperatures. The package has been demonstrated with inertial, resonant, and RF MEMS.

This paper presents a high-speed resolution phase-only microelectromechanical system (MEMS) spatial light modulator (SLM), integrated with driver electronics, using through- wafer vias and solder bump bonding. It employs a polysilicon thin film MEMS technology that is well suited to micromirror array fabrication and offers significant improvement in SLM speed in comparison to alternative modulator technologies. Vertical through-wafer interconnections offer scalability required to achieve 1M-pixel array size. The design, development, fabrication and characterization of a scalable driver integrated SLM is discussed. Pixel opto- electromechanical performance has been quantified experimentally on prototypes, and results are reported.