Integrated pyroelectric sensors based on hafnium oxide
Pyroelectric sensors have many applications in the fields of gas analysis, flame sensing, process technology and infrared detection. Many pyroelectric materials used so far are not compatible with modern manufacturing processes or are even toxic. At Fraunhofer IPMS, research is being carried out on sensors based on hafnium oxide, which have many advantages over conventional materials. In particular, the compatibility with semiconductor manufacturing processes (CMOS compatibility) and environmental compatibility (RoHS compatibility) make the material interesting for future integrated sensor applications. Compared to semiconductor detectors, pyroelectric sensors have a broad spectral sensitivity without the need for active cooling.
Hafnium oxide has a long history in semiconductor technology. The pyroelectric properties of the material have only been explored in recent years, opening up new possibilities for the fabrication of highly integrated and miniaturised sensor devices. Pyroelectric thin films based on hafnium oxide show promising properties for a variety of applications. In addition to sensor applications, the recovery of heat loss (so-called "energy harvesting") and electrocaloric cooling are also the subject of active research at Fraunhofer IPMS.