An integrated radiation sensor for detecting the presence of an environmental material and/or condition includes a sensing structure and first and second lateral bipolar junction transistors (BJTs) having opposite polarities. The first lateral BJT has a base that is electrically coupled to the sensing structure and is configured to generate an output signal indicative of a change in stored charge in the sensing structure. The second lateral BJT is configured to amplify the output signal of the first bipolar junction transistor. The first and second lateral BJTs, the sensing structure, and the substrate on which they are formed comprise a monolithic structure.

An integrated radiation sensor for detecting the presence of an environmental material and/or condition includes a sensing structure and first and second lateral bipolar junction transistors (BJTs) having opposite polarities. The first lateral BJT has a base that is electrically coupled to the sensing structure and is configured to generate an output signal indicative of a change in stored charge in the sensing structure. The second lateral BJT is configured to amplify the output signal of the first bipolar junction transistor. The first and second lateral BJTs, the sensing structure, and the substrate on which they are formed comprise a monolithic structure.

Betavoltaic battery devices and methods of making are presented. In embodiments, an electrically inactive betavoltaic battery device comprises: a p-type semiconductor layer including at least one stable isotope that transforms into a beta emitter upon irradiation with thermal neutrons; and an n-type semiconductor beta-absorber layer configured to absorb beta particles; wherein the p-type semiconductor layer and the n-type semiconductor layer form a p-n diode, and wherein the electrically inactive betavoltaic battery device is configured to be transformed into an electrically active betavoltaic battery upon irradiation with thermal neutrons. The electrically inactive betavoltaic battery device may be transported to an irradiation facility, where it is irradiated with thermal neutrons to convert the inactive betavoltaic batter device to an active betavoltaic battery device.