Betavoltaic apparatus and method

摘要

An exemplary thinned-down betavoltaic device includes an N+ doped silicon carbide (SiC) substrate having a thickness between about 3 to 50 microns, an electrically conductive layer disposed immediately adjacent the bottom surface of the SiC substrate; an N− doped SiC epitaxial layer disposed immediately adjacent the top surface of the SiC substrate, a P+ doped SiC epitaxial layer disposed immediately adjacent the top surface of the N− doped SiC epitaxial layer, an ohmic conductive layer disposed immediately adjacent the top surface of the P+ doped SiC epitaxial layer, and a radioisotope layer disposed immediately adjacent the top surface of the ohmic conductive layer. The radioisotope layer can be 63Ni, 147Pm, or 3H. Devices can be stacked in parallel or series. Methods of making the devices are disclosed.

主权项

1. A betavoltaic device, comprising:
an N+ doped semiconductor substrate having a top surface and a bottom surface and a thickness tN+ between the top and bottom surfaces, where tN+ is equal to or less than 100 micrometers (μm); an electrically conductive layer disposed immediately adjacent the bottom surface of the substrate; an N− doped epitaxial layer having a top surface, disposed immediately adjacent the top surface of the substrate; a P+ doped epitaxial layer having a top surface, disposed immediately adjacent the top surface of the N− doped epitaxial layer; an ohmic conductive layer having a top surface, disposed immediately adjacent the top surface of the P+ doped epitaxial layer; and a radioisotope layer disposed immediately adjacent the top surface of the ohmic conductive layer,wherein coincident regions of at least a portion of the radioisotope layer, the second electrically conductive layer, the P+ doped epitaxial layer, and the N− doped epitaxial layer, and the N+ doped substrate are etched so as to provide a plurality of devices including a common N+ doped substrate and first electrically conductive layer.