SUSS MicroOptics - High Quality Microlens Arrays
- September 2010 New invited talk of Dr. Reinhard Voelkel at the EOS Annual Meeting (26.10.-29.10. in Paris):
Micro-optics: Key Enabling Technology (KET) for Advanced Mask Aligner Lithography
- April 2010 Talk: Half-tone Proximity Lithography in SUSS Mask Aligner (7716-34)
The Square Conference Ctr., Brussels, Belgium
Wednesday, April 14, 2010, Location: 211/212, Time: 11:40 - 12:00
Authors: Torsten Harzendorf, Lorenz Stürzebecher, Uwe D. Zeitner, Fraunhofer-Institut für Angewandte Optik und Feinmechanik (Germany), Uwe Vogler, Reinhard Voelkel, SUSS MicroOptics SA (Switzerland);
Abstract: The half-tone lithography using pixelated chromium masks in a projection stepper is an established technology in micro-optics fabrication. However, the projection lithography tool is comparably expensive and the achievable lateral resolution is typically limited. By using pixel diffraction effects, binary and continuous profile lithography with submicron resolution can be installed on a conventional mask aligner. To achieve this goal the control of both, the angular spectrum of the illumination and the mask features is essential. We used a novel micro-optics based illumination system referred as "MO Exposure Systems" in a SUSS MA6 mask aligner for the dedicated shaping of the angular illumination distribution. In combination with an adapted lithography mask the formation of a desired intensity distribution in the resist layer is possible. A general mathematic model describes the relation between the angular spectrum of the mask illumination, pixel size and pitch in the mask, proximity distance and propagated field, which also includes special cases like Talbot imaging. We show that a wide range of different micro-optical structures can be optimized by controlling the light diffraction in proximity lithography. Parameter settings will be found for submicron binary pattern up to continuous profile structures with extensions up to several tens of microns. An additional interesting application of this approach is the combination of binary and continuous profiles in single elements, e.g. lens segments or lenses with diffractive correction or AR structures. Experimental results achieved for different structure types, like high aspect ratio holes, blazed gratings with a period smaller than 2 microns and arbitrary shaped lens arrays will be presented.
- March 2010SUSS now introduces Source-Mask Optimization for Mask Aligner Lithography. Source-Mask Optimization (SMO) is a photolithography enhancement technique commonly used in optical lithography to compensate for image errors due to diffraction and process effects. Source-Mask Optimization comprises different measures like Customized Illumination, Optical Proximity Correction (OPC), Polarized Phase Shift Masks (P:PSM) and Resolution Enhancement Techniques (RET). Primary goals are to improve CD control, increase resolution and depth of focus (DOF), improve manufacturability and enlarge the process window.
Information on Source-Mask Optimization can be found on www.mask-aligner.info.
- February 2010New article online: Micro-Optics: From High-End to Mass-Market - Optik & Photonik No 4, (2009) (pdf - 324kb)
- Januar 2010Top ranking: The article "Inside Wafer-Level Cameras" achieved rank 39 in the Semiconductor_International's Top 100 list for 2009
(Authors: Reinhard Voelkel, SUSS MicroOptics SA, Neuchâtel, Switzerland; Ralph Zoberbier, SUSS MicroTec Lithography, Garching, Germany; publication in Semiconductor International, 2/1/2009)