Share Email Print

Proceedings Paper

Fabrication of large-scale monocrystalline silicon micro-mirror arrays using adhesive wafer transfer bonding
Author(s): Fabian Zimmer; Frank Niklaus; Martin Lapisa; Thomas Ludewig; Martin Bring; Martin Friedrichs; Thor Bakke; Harald Schenk; Wouter van der Wijngaart
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Today, spatial light modulators (SLMs) based on individually addressable micro-mirrors play an important role for use in DUV lithography and adaptive optics. Especially the mirror planarity and stability are important issues for these applications. Mono-crystalline silicon as mirror material offers a great possibility to combine the perfect surface with the good mechanical properties of the crystalline material. Nevertheless, the challenge is the integration of mono-crystalline silicon in a CMOS process with low temperature budget (below 450°C) and restricted material options. Thus, standard processes like epitaxial growth or re-crystallization of poly-silicon cannot be used. We will present a CMOS-compatible approach, using adhesive wafer transfer bonding with Benzocyclobutene (BCB) of a 300nm thin silicon membrane, located on a SOI-donor wafer. After the bond process, the SOI-donor wafer is grinded and spin etched to remove the handle silicon and the buried oxide layer, which results in a transfer of the mono-crystalline silicon membrane to the CMOS wafer. This technology is fully compatible for integration in a CMOS process, in order to fabricate SLMs, consisting of one million individually addressable mono-crystalline silicon micro-mirrors. The mirrors, presented here, have a size of 16×16 μm2. Deflection is achieved by applying a voltage between the mirrors and the underlying electrodes of the CMOS electronics. In this paper, we will present the fabrication process as well as first investigations of the mirror properties.

Paper Details

Date Published: 18 February 2009
PDF: 9 pages
Proc. SPIE 7208, MOEMS and Miniaturized Systems VIII, 720807 (18 February 2009); doi: 10.1117/12.808694
Show Author Affiliations
Fabian Zimmer, Fraunhofer Institute for Photonic Microsystems (Germany)
Frank Niklaus, KTH Royal Institute of Technology (Sweden)
Martin Lapisa, KTH Royal Institute of Technology (Sweden)
Thomas Ludewig, Fraunhofer Institute for Photonic Microsystems (Germany)
Martin Bring, Fraunhofer Institute for Photonic Microsystems (Germany)
Martin Friedrichs, Fraunhofer Institute for Photonic Microsystems (Germany)
Thor Bakke, SINTEF (Norway)
Harald Schenk, Fraunhofer Institute for Photonic Microsystems (Germany)
Wouter van der Wijngaart, KTH Royal Institute of Technology (Sweden)

Published in SPIE Proceedings Vol. 7208:
MOEMS and Miniaturized Systems VIII
David L. Dickensheets; Harald Schenk; Wibool Piyawattanametha, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?