Design and Characterization of Next-Generation Micromirrors Fabricated in a Four-Level, Planarized Surface-Micromachined Polycrystalline Silicon Process

Technical Report · Wed Dec 31 04:00:00 EST 1997

DOI:https://doi.org/10.2172/622545· OSTI ID:622545

Michalicek, M A; Comtois, J H ^[1]; Barron, C C ^[2]

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1. Phillips Lab., Kirtland AFB, NM (United States). Space Technologies Directorate
2. Sandia National Labs., Albuquerque, NM (United States)

This paper describes the design and characterization of several types of micromirror devices to include process capabilities, device modeling, and test data resulting in deflection versus applied potential curves. These micromirror devices are the first to be fabricated in the state-of-the-art four-level planarized polysilicon process available at Sandia National Laboratories known as the Sandia Ultra-planar Multi-level MEMS Technology (SUMMiT). This enabling process permits the development of micromirror devices with near-ideal characteristics which have previously been unrealizable in standard three-layer polysilicon processes. This paper describes such characteristics as elevated address electrodes, individual address wiring beneath the device, planarized mirror surfaces using Chemical Mechanical Polishing (CMP), unique post-process metallization, and the best active surface area to date. This paper presents the design, fabrication, modeling, and characterization of several variations of Flexure-Beam (FBMD) and Axial-Rotation Micromirror Devices (ARMD). The released devices are first metallized using a standard sputtering technique relying on metallization guards and masks that are fabricated next to the devices. Such guards are shown to enable the sharing of bond pads between numerous arrays of micromirrors in order to maximize the number of on-chip test arrays. The devices are modeled and then empirically characterized using a laser interferometer setup located at the Air Force Institute of Technology (AFIT) at Wright-Patterson AFB in Dayton, Ohio. Unique design considerations for these devices and the process are also discussed.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE Assistant Secretary for Management and Administration, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 622545
• Report Number(s): SAND--97-2532C; CONF-971088--; ON: DE98000384
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
ARMD(AXAIAL-ROTATION MICROMIRROR DEVICE)
CMP(CHEMICAL MECHANICAL POLISHING)
DESIGN
ELECTRODES
EXPERIMENTAL DATA
FABRICATION
FBMD(FLEXURE-BEAM MICROMIRROR DEVICE)
INTERFEROMETRY
LASERS
MEMS(MICROELECTROMECHANICAL SYSTEMS)
MICROMIRRORS
MIRRORS
POLISHING
POLYCRYSTALS
PROCESSING
SILICON
SPUTTERING
SUMMIT(SANDIA ULTRA PLANAR MULTI-LEVEL MEMS TECHNOLOGY)
TESTING