The freezing out phenomenon in semiconductors must be taken into account in the development of high-precision semiconductor sensors, especially at low temperatures.
At low temperatures, the doping atoms are not completely ionized, which leads to a reduction of the charge carrier concentration (freezing out).
The semi-classical approaches used so far are limited in their prediction. In the freezing-out project, quantum mechanical calculations and extensive measurements were performed on semiconductors in the temperature range from 300K to 4K. This served to put future simulations in the MEMS field and the semiconductor industry in this temperature range on a better data basis and to make them more reliable.
The temperature range from 300K to 4K is becoming increasingly important for microsystems and components. These include detectors and temperature sensors, which are used either as individual components or in systems as integrated sensors with other components (e.g. pressure sensors). In addition, sensor technology will be needed in the future that is used in connection with liquid hydrogen (-252.85°C).
In the “Freezing out” project, extensive data material was generated for charge carrier mobility and concentration at numerous dopants, which can be implemented in existing simulation tools. This will significantly accelerate new product developments due to the improved informative value of the simulation results and, at the same time, make product developments more cost- and resource-efficient.
The research and development work described was funded by the German Federal Ministry of Economic Affairs and Climate Action (BMWK) as part of the “Freezing out” research project.
Funding code: 49VF190056
