The institute: The Walter Schottky Institute (WSI) is a central institute of the Technische Universität München (TUM) which was founded in 1986 in order to strengthen the interaction between basic physics and semiconductor electronics research. It became operational in May 1988. Today the WSI accommodates four research groups (Experimental Semiconductor Physics I and II, Semiconductor Technology and Theoretical Semiconductor Physics). A total staff of about 90 persons includes scientific and technical staff, secretaries and doctorate as well as diploma (master) students. Out of these, about 25 permanent positions are authorized by the TUM and belong to the department of physics and the department of electrical engineering and information technology, respectively, while basically all the doctorate candidates and postdoctoral positions are financed via external research projects from different funding agencies. The WSI is participating in several joint projects in national and international collaboration with industrial research laboratories, Fraunhofer Institutes, Max-Planck Institutes and many other universities.

The resources: The semiconductor technology group, headed by M.-C. Amann, mainly focuses on research towards advanced optoelectronic and microwave semiconductor devices and technologies. This work is based on a well-equipped III/V semiconductor technology laboratory including a 250 m² clean room, 3 MBE (GaAs, InP and GaSb) and one MOVPE (InP) machines, photolithography and a scanning electron microscope with e-beam writing facility, dry-etching techniques, sputtering and evaporation equipment for metals and dielectrics as well as the essential wafer characterization techniques (XRD and PL). The device characterization includes optical measurement setups for temperature-controlled stationary characterisation of laser diodes.

The role in the project: The role of the WSI in the project is to establish and to extend the BTJ-VCSEL-technology from the previous InP-based materials to GaSb-based ones. Besides large efforts spent on the device technology further work will be on realising high-performance Antimonide-based Bragg mirrors and active regions for the entire 2.5-3.5 µm wavelength range. The goal is to achieve electrically pumped room-temperature or at least near-room-temperature (1 stage Peltier cooling) devices operating in a single mode under cw conditions.