High-sensitive pyroelectric detectors with internal thermal amplification

A novel procedure for increasing the sensitivity of pyroelectric detectors and its mathematical and physical analysis are presented. Due to a three-dimensional pattern that is etched into the sensitive element lateral heat flux spreading is used to improve the responsivity. Here, the effect is used, that very thin regions between thicker regions show a faster heating due to incident radiation and, hence, lead to an additional heat flow from this intermediate regions to the sensitive element. The analysis allows the description of the thermal and electrical behavior of the sensitive element depending on the dimensions of the pattern and the modulation frequency.