Innovations with Microwaves and Light

The FBH develops high-power diode lasers and and electronic devices which are even smaller than a rice grain

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, power electronics and sensor technology. High-power diode lasers with excellent beam quality are produced for materials processing, medical tech­nology and high-precision metrology.FBH researches and develops nitride-based devices 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. As a result of the market- and customer-orientation, FBH launched ten spin-off companies and was awarded with several prizes for its successful technology transfer. “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.” With its university cooperation model, FBH joins forces with university research and thus successfully bridges the gap between basic and application-oriented research.

The institute has a staff of 290 employees and a budget of 28 million Euros. It is part of the Forschungsverbund Berlin e.V., a member of the Leibniz Association and plays an active role in various networks.

Intelligent solutions in use

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 30 Watt (cw operation) or even 200 Watt (short-pulse operation): 5,000 and 25,000 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 atomic 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 in optical precision spectroscopy, sensor technology, metrology and materials pro­cessing (welding, soldering, labeling).

Since several years, FBH develops hybrid laser modules integrating beam shaping optics, external resonators and oscillator-amplifier combinations. Such modules are only as small as matchboxes and may replace large-format laser types the size of a closet, which are used for example in complex large-scale projections (planetariums, flight simulators). A completely new approach offers the FBH with its compact picosecond light source with integrated pulse picker. The source combines RF technology and electronics with the development of high-power diode lasers – both of which are core competencies at the institute. The source is suited for applications such as laser materials processing and biomedical investigations (fluorescence spectroscopy).

FBH’s electronic devices are regularly used in communication technology and power electronics. In fields like wireless communications, environmentally-friendly information and communication technologies which additionally reduce operating costs are essential. Such Green IT applications strongly require improved amplifiers. Microwave power amplifiers do not only make the lion’s share of base station’s energy consumption, but are also a precondition for next-generation mobile communications providing higher band­widths and new spectrum-efficient modulation techniques.

The Ferdinand-Braun-Institut has also expanded its activities in the field of terahertz electronics. FBH offers several microwave monolithic integrated circuits (MMIC) technologies reaching cut-off frequencies above 300 GHz. Design kits exist for stand-alone processes and the heterointegrated InP-on-BiCMOS process, SciFab. This foundry process combines the advantages of two high-frequency semiconductor technology worlds – high complexity BiCMOS (IHP, Leibniz-Institut für innovative Mikroelektronik) paired with high-power InP DHBT (FBH) technology. The unique wafer-level integration leads to a reduction in size, weight, and dissipated power as compared to existing assembly techniques.

Research and development on a firm footing

Research and development in microwaves and optoelectronics are based on the same technologies. By means of epitaxy gauzy layers with the desired material properties are developed on wafers via MOVPE  and HVPE techniques. Modern, industry-compatible equipment processes these 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 electronic devices. 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.

One-stop solutions & services

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 to small-scale series.

Services include the epitaxy of customized III-V semiconductor layer structures, struc­turing processes and tailored high-power diode lasers and electronic devices. FBH also offers services in design and simulation, mounting and packaging as well as reliability testing.