Tritiation of amorphous and crystalline silicon using T <inf>2</inf> gas

Incorporation of tritium in hydrogenated amorphous silicon (a-Si:H) and crystalline silicon (c-Si) at 250 °C using tritium (T 2) gas at pressures of up to 120 atm is reported. The tritium is stored in a surface layer which is approximately 150 and 10 nm for a-Si:H and c-Si, respectively. The concentration of tritium occluded in planar and textured c-Si is linearly dependent on the total surface area. The tritium is stable and the dominant tritium evolution occurs at temperatures above 300 °C. The concentration of tritium locked in a-Si:H and c-Si was 20 and 4 at. %, respectively. Self-catalysis appears to be important in the tritiation process. © 2006 American Institute of Physics

Power-scaling performance of a three-dimensional tritium betavoltaic diode

Three-dimensional diodes fabricated by electrochemical etching are exposed to tritium gas at pressures from 0.05 to 33 atm at room temperature to examine its power scaling performance. It is shown that the three-dimensional microporous structure overcomes the self-absorption limited saturation of beta flux at high tritium pressures. These results are contrasted against the three-dimensional device powered in one instance by tritium absorbed in the near surface region of the three-dimensional microporous network, and in another by a planar scandium tritide foil. These findings suggest that direct tritium occlusion in the near surface of three-dimensional diode can improve the specific power production. © 2009 American Institute of Physics

Tritium locked in silica using 248 nm KrF laser irradiation

In this Letter we report on selectively occluding tritium in a silica film on a silicon substrate using a combination of high-pressure tritium loading and 248 nm KrF laser irradiation. Sixty percent of tritium dissolved in the silica film was bonded by laser irradiation. The concentration of the bonded tritium was proportional to the total laser fluence. Tritium effusion experiments indicated that the laser-locked tritium existed stably in the glass matrix up to 400 °C. In this work we point a way to a safe and simple approach for the integration of on-chip radioisotope micropower sources for micromechanical and microelectronic applications. © 2006 American Institute of Physics