Abstract: Disclosed herein is a device that includes at least one functional semiconductor element; and static electric field source(s) associated with the at least one functional semiconductor element, the static electric field source(s) comprising at least one electret component and having a heterogeneous charge distribution. Also disclosed herein is a device includes a functional semiconductor element; a static electric field source comprising at least one electret element, the static electric field source imparting a static electric field to the functional semiconductor element; and at least one nuclear radiation source for continuously imparting nuclear beta radiation to the at least one electret element and/or the functional semiconductor element. Use of at least a radioactive beta source for replenishing charge in an electret, as well as use of at least a radioactive beta source for simultaneously replenishing charge in an electret and modifying charge mobility of a semiconductor material, are also disclosed.