A betavoltaic microcell based on semiconducting single-walled carbon nanotube arrays/Si heterojunctions

In this paper, a novel betavoltaic (BV) microcell based on semiconducting single-walled carbon nanotube (s-SWCNT) arrays/Si heterojunctions are demonstrated for the first time. The aligned arrays of p-type s-SWCNTs were prepared on n-type silicon to form the p-n heterojunctions as energy conversion by the traditional micro-fabrication process and dielectrophoretic (DEP) technology. The s-SWCNT arrays/Si p-n heterojunction displays better rectification characteristics than the SWCNT-based Schottky junctions such as Au/s-SWCNT/Ti and SWCNTs thin film/Si in our previous works. Under 7.8mCi/cm^{2 63}Ni irradiation, the open circuit voltage (V_OC) of 62mV, short current density (J_SC) of 3.8μA/cm², fill factor (FF) of 33.4% and energy conversion efficiency (η) of 9.8% were achieved. The results indicated that this s-SWCNT arrays/Si microcell has a huge potential for application in BV microcells.