Observation of Large, Anomalous Pyroelectric Response in AlN Thin Films

Abstract

ABSTRACTWe have observed a pyroelectric effect (PE) in reactively sputtered aluminum nitride (AlN) thin films that is typically a factor of twenty greater than commercial pyroelectric materials such as triglycine sulfate (TGS). This is most likely due to an extrinsic effect since the known crystalline structures of AlN are too symmetric to allow such high values for the PE response. Preliminary annealing studies support the assumption that residual strains remaining from the AlN thin film deposition are the most likely source of the anomalously high PE response. The results of these studies are presented along with some measurements that indicate a still higher PE response might be obtainable.