Innovations with Microwaves and Light

The FBH develops high-power diode lasers and microwave devices which are even smaller than a grain of sand

The Ferdinand-Braun-Institut, Leibniz-Institut fuer Hoechstfrequenztechnik (FBH) is one of the internationally leading institutes for applied research in microwaves and optoelectronics. Based on III-V semiconductors it manufactures high-frequency devices and circuits for communication and sensor technology. High-power diode lasers with excellent beam quality are produced for materials processing, laser technology, medical technology and high-precision metrology. FBH also conducts basic investigations on nitrides for future applications such as short-wave UV light sources or transistors for very high voltages.

In order to assure rapid transfer of technology FBH works closely with partners and customers in industry and the scientific community. For its successful technology transfer FBH was awarded with several prizes. As a result of the subsequent market- and customer-orientation FBH launched five spin-off companies. "We are not only scientists, but also an interface between research and industry", explains Prof. Günther Tränkle, director of the Ferdinand-Braun-Institut, "thus in our research we take into account at an early stage the interests of potential customers."

The institute has a staff of 230 employees and a budget of 21 million Euro. It is part of the Forschungsverbund Berlin e.V. (FVB) and is a member of the Leibniz Association. FBH plays an active role in various networks, for example in OpTecBB, a competence network for optical technology, and in ZEMI, the center for microsystems technology in Berlin.

FBH diode lasers are characterized by small dimensions and great precision as well as by high brilliance and efficiency. In spite of its small size a single laser emits up to 20 Watt (cw operation) or even 100 Watt (short pulse operation): 5000 and 25000 times respectively greater power than a laser in a CD player.

These characteristics along with the extraordinarily high reliability under extreme conditions have earned FBH lasers approval for use in space applications, such as, for example, in atom clocks for the latest generation of GPS satellites. There is a wide field of applications for the brilliant light sources. In medical technology they are used in photodynamic cancer therapy. During treatment tumor cells are enriched with a medication. When light of a precisely defined wavelength hits the cell, it activates the active agent and the afflicted cells are destroyed. Applications are also applied in metrology and materials processing, such as welding and soldering.

FBH microwave devices are regularly used in communication technology. Their efficiency and small size have enabled the production of ever-smaller cell phones. Approximately 2,000 chips with microwave circuits fit on a 4“ wafer. With laser chips the number can be as high as 10,000 pieces on the disc with a diameter of ten centimeters. This enables the production of a large number of items on one wafer and thus reduces manufacturing costs.

FBH also develops intelligent solutions for fixed parts in mobile communications. Compact and highly efficient circuits, placed close to the peak of the antenna, need less than half the energy of ordinary systems. In addition they require significantly less cooling effort. A further example is radar sensors in driver assistance systems to increase road safety. They facilitate parking, regulate speed when cars tailgate, and cautions drivers of collision risks.

In extension of its research on microwave III-V power components, the Ferdinand-Braun-Institut develops microwave plasma sources especially in the emerging field of atmospheric microplasmas. Due to their high potential in creating new plasma applications for e.g. medicine, biology, semiconductor industry and industrial surface engineering as well as the possibility to transfer low-pressure plasma applications to much more cost-effective atmospheric processes, these activities represent a very promising field.

Research and development in microwaves and optoelectronics are based on the same basic technologies. By means of epitaxy gauzy layers with the desired material properties are developed on wafers. This process is executed at FBH by metal organic vapor phase epitaxy (MOVPE). In a reactor gaseous metal compounds are deposited at high temperature atomic layer upon atomic layer. The HVPE process is particularly used for explorative research to realize gallium nitride and aluminium nitride substrates. Modern, industry-compatible equipment processes the wafers. The process line comprises photolithographic methods, wet and dry chemical etching and metalization. Finally, technicians separate the chips from the wafer and mount them as optoelectronic or radio-frequency devices.

FBH develops high-value products and services for its partners in the research community and industry and tailors each precisely to fit individual needs. As a one-stop-agency the institute offers its international customer base know-how and complete solutions from design to ready-to-ship modules, from development orders to small scale series.

Services include the epitaxy of customized III-V semiconductor layer structures, the development and structuring processes for the manufacture of tailor-made high-power diode lasers and radio-frequency devices. FBH also offers services in design and simulation, mounting and packaging as well as reliability testing.

[Overview, pdf]