Investigation of IC thermal problems
A very successful field is the investigation of the thermal problems of integrated circuits, thermal measurement and thermal design of ICs. Our world-wide reputation in this field was fostered by participation in many international projects. We are proud to get founding among the firsts for our Framework 5 research project PROFIT, with partners like Philips, Nokia, St. Microelectronics, Infineon, Tima and Oriered, where all the listed partners will exploit the research results of our department. The department is one of the main organisers of the THERMINIC conferences. There are numerous papers published by the staff of the department in this field. The main results of research in the thermal field are as follows:
- Development of new algorithms for the steady-state and dynamic heat distribution simulation of IC chips. This work resulted in the research version of the THERMAN and SUNRED simulation programs.
- Measurement of the surface temperature distribution of an operating integrated circuit, using liquid crystal coating. The developed equipment automatically generates the surface heat map on the PC screen. The temperature resolution of the obtainable image is better than 0.1 °C. The spatial resolution is 2-4 µm.
- New measuring and identification method to determine the details of the heat-flow path of a semiconductor device. A four-channel measuring equipment has been developed for the registration of package thermal responses, with a resolution of 1 µs and 0.012 °C. The original evaluation method of these responses provides the thermal map of the heat path between the chip and the ambience.
- IC temperature sensors, thermal monitoring. We have investigated the principles and practical solutions for the built-in thermal monitoring of IC's and boards, its connection with boundary-scan. This work resulted in the development of the THERMOSENS CMOS compatible digital output temperature sensor family. We have developed the experimental version of the electro-thermal simulation package (SISSI) and a compact thermal model generator program (THERMODEL). Further information and multimedia demonstration about the above mentioned research results is available on our WEB page.
Characterisation of semiconductor surfaces and very thin oxides
This research includes the work function measurements on solid surfaces by vibrating capacitor (Kelvin) method, the development of the scanning version of the vibrating capacitor method for surface potential, surface state density mapping of silicon wafers and the measurement of the light-induced surface potential transients on Si surfaces covered by ultra thin (tunnel) oxide. Further fields are the investigation of catalitically activated semiconductor gas sensors, the generation of olfactory images from the surface potentials measured on the gas sensitive surfaces, the development of semiconductor (tin-dioxide) sensors and the investigation of nanocrystals produced by agglomeration of ultra thin metal layers for activating semiconductor sensors.
The investigation and modelling of small-size and new semiconductor devices comprises the Monte Carlo modelling of deep submicron MOS devices, the development of circuit models for submicron MOS FET's, the investigation of very thin (tunnel) gate oxide, new high-k gate dielectric and other tunnel-oxide devices.
Research in optoelectronics
Research in optoelectronics includes the design of semiconductor optoelectronic integrated circuits, the modelling of optoelectronic parameters of AIIIBV semiconductor compounds, the design of optical filters with quasi-periodic structures, the simulation of composite cavity semiconductor lasers, and the development of new design tools for two-dimensional photonic bandgap systems.
Media and system informatics field
Media and system informatics field embraces the research of digital and analogue low-power circuits, the development of VHDL-based circuit synthesis methods, the testing and monitoring the Linux server reliability and the development of microprocessors and microcontrollers. Additional fields are the fetal monitoring, research of real-audio speaker's recognition and identification procedures, monitoring radio streams in the Internet, and development of multimedia databases and information centres with platform independent interface.