Research highlights from Fraunhofer IPMS

© 2013 Sven Döring / Agentur Focus

Waferabbildung eines eindimensionalen Flächenlichtmodulators.

Spatial Light Modulators

The spatial light modulators developed at Fraunhofer IPMS consist of arrays of micromirrors on semiconductor chips, whereby the number of mirrors varies depending on the application, from a few hundred to several millions. In most cases this requires a highly integrated application-specific electronic circuit (ASIC) as basis for the component architecture in order to enable an individual analog deflection of each micromirror. In addition, Fraunhofer IPMS develops electronics and software for mirror array control.

The individual mirrors that vary in number and size per chip can be tilted or vertically deflected depending on the application, so that a surface pattern is created, for example to project defined structures. High-resolution tilting mirror arrays with up to 2.2 million individual mirrors are used by our customers as highly dynamic programmable masks for optical micro-lithography in the ultraviolet spectral range. The mirror dimensions are 10 μm or larger. By tilting the micromirrors, structural information is transferred to a high-resolution photo resist at high frame rates. Further fields of application are mask inspection and measurement technology for the semiconductor industry, microscopy and prospectively laser printing, marking and material processing.

Piston micromirror arrays can for example be used for wavefront control in adaptive optical systems. These systems can correct wavefront disturbances in broad spectral ranges and thereby improve image quality. The component capabilities attract special interest in the fields of ophthalmology, astronomy and microscopy, as well as in spatial and temporal laser beam and pulse shaping.

© 2013 Sven Döring / Agentur Focus

Optischer Scankopf einer 3D-TOF-Kamera mit integriertem MEMS Scannerspiegel-Array des Fraunhofer IPMS.

© Fraunhofer IPMS

Flüssigkristall-Wellenleiter.

MEMS Scanners

To date, more than 50 different resonant scanners have been designed and manufactured. They are made to deflect light either one-dimensionally or two-dimensionally or for high-speed optical path length modulation. Scan frequencies from 0.1 kHz to 50 kHz have been successfully executed. Applications range from reading barcode and data code, through 3D metrology, and right up to laser projection and spectroscopy. An example is a MEMS scanner with integrated diffraction grating for spectroscopic applications which HiperScan GmbH, a Fraunhofer IPMS spin-off, has been distributing since 2007 a novel infrared wavelength micro spectrometer. Furthermore, the Fraunhofer IPMS is engaged in custom-designed scanning mirrors, e.g. for Fourier Transform spectrometers, confocal microscopy, highly miniaturized displays, ultra-compact laser projection systems, endoscopic image acquisition as well as triangulation.

In addition to resonant scanners, quasi-static micro-scanners are also under development. These activities are geared toward applications such as laser beam positioning and switching.

The internet platform www.micro-mirrors.com was introduced, allowing customers to define and order resonant micro-scanners that are suitable for their specific applications. Thanks to a building-block approach, we are able to offer reasonably-priced devices with a short lead time.

© Fraunhofer IPMS

Mit der Li-Fi-GigaDock-Technologie können kurze Kabel und Steckverbinder bei Datenraten von bis zu 12,5 GBit/s ersetzt werden.

Wireless Microsystems

The business unit “Wireless Microsystems” provides product-related partial and complete solutions for customer- and application-specific problems of hard- and software. This includes optical wire­less communication (Li-Fi), maintenance-free and battery-free RFID sensor nodes, integrated intercon­nected systems, track and trace as well as big data and data analysis. Technological priorities lie in the development of components and modules for RFID and Li-Fi. Supported technology nodes for passive transponders are LF, HF, NFC and UHF. The focus is on antenna design, custom RF ASICs, sensor integration and interconnected RFID platforms via OPC UA. The developments of Li-Fi technology are divided into docking and hot spot solutions for data rates of a few kilobits per second up to the current maximum transmission rate of 12.5 Gbps. The aim is to replace plugs, cables and wireless technologies by perfor­mant, real-time optical wireless communication in various applications. Development focuses on optics, analog front ends, specific protocols and protocol adapters to easily connect Li-Fi solutions to existing infrastructure.

OPC UA coupled RFID sensor networks and real time location services in buildings provide the basis to develop user-specific value-added services. These services include indoor navigation, location-based services, locating assets in manufacturing, electronic lot traveller and production optimization, workforce management, preventive maintenance of equipment and much more.

© Fraunhofer IPMS

Hyperspektralen Bildgebung am Beispiel eines Apfels.

Environmental Sensing

The “Environmental Sensing” (ENV) business unit focuses on the development of sensory de­vices, components and subsystems to be used in application-specific devices for the detection and evaluation of environmental conditions. For this purpose, Fraunhofer IPMS develops silicon-based microsystems technology components such as solid-state sensors, ultrasonic transducers as well as photonic sensors and modulators. These sensory elements are fully-developed over functional models, prototypes and pre-series to ultimately be used in systems designed and implemented in the business unit. The wide range of application areas includes food monitoring, water and soil analysis, industrial metrology, security and medical technology. In ad­dition, Fraunhofer IPMS can provide feasibility stud­ies, test measurements and the characterization of sensory elements and systems.

Know-how specific to the business unit includes comprehensive knowledge for the production of MEMS components and characterization as well as performance and operating-point determination for each application. Highly precise, state-of-the-art micro-mounting equipment that allows accurate placement of devices in the single-digit micrometer range as well as spectral characterization tools (e.g., various spectrometer types NIR to FTIR, spectro­graphs, monochromator with integrating sphere, FFT analyzer) are utilized. Upon this foundation, it is, for example, possible to construct state-of-the-art minia­ture optical spectrometers in the size of a sugar cube.

© Fraunhofer IPMS

300 mm Reinraum des Center Nanoelectronic Technologies CNT.

Center Nanoelectronic Technologies CNT

At the Center Nanoelectronic Technologies (CNT), Fraunhofer IPMS carries out applied research on 300 mm wafers for IC manufacturers, suppliers, equipment manufacturers and R&D partners. The Fraunhofer IPMS - CNT offers the following services on Ultra Large-Scale Integration (ULSI) level:

  • 300 mm DEVICES & VALUE ADDED SOLUTIONS
  • 300 mm SCREENING FAB SERVICES

The Center Nanoelectronic Technologies has its own 800 m² clean room with 40 processing and analytic tools for 200/300 mm wafer and offers professional wafer handling for a smooth wafer exchange (short loops).

Industry standards guarantee a risk-free and quick integration of new developments and process innovations into the production lines of our customers to save costs and time.

© Fraunhofer IPMS

Vereinfachte Darstellung einer MEMS-basierten Mikropumpe basierend auf dem NED-Ansatz. Das Bild zeigt nichtausgelenkte Biegeaktoren (grün), ausgelenkte NED-Biegeaktoren (rot) sowie Ein- und Auslassventile (gelb).

Mesoscopic Actuators and Systems

Hardly any fast-growing technical industry can exist without components for microsystems technology in terms of sensors and actuators. In order to meet the growing demands on the performance of micromechanical components and expand the technical base for new applications, further miniaturization is essential. The miniaturization as part of a technical evolution further means, that novel principles for micro- and nanomechanical systems are required. For this purpose, the Fraunhofer project group »Mesoscopic Actuators and Systems« (MESYS) is developing a new class of electrostatic bending actuators (NED) and tests these actuators in MEMS-based microsystems on various fields of applications.