The design of diamond metal/intrinsic/p-type Schottky-barrier-based cells for different radioactive β sources

In this work, we actively investigated a betavoltaic cell model that demonstrated high accuracy and reproducibility, utilizing both Monte Carlo (MC) simulations and Technology Computer-Aided Design (TCAD) for its development. This model integrates diamond-based metal/intrinsic/p-doped (MIP) Schottky diode structures and employs the following commonly utilized radioactive isotopes: ⁶³Ni, ¹⁴⁷Pm, ¹⁴C, and ³H. The optimal response of the MIP structure devices to these four radiation sources has been refined through computational modeling. To achieve optimal efficiency from betavoltaic cells when exposed to various radiation sources, design parameters were obtained, a 9 µm thick i-layer with a doping concentration of 1E14 cm^− 3 under 2 µm of ⁶³Ni, yielding an efficiency of 10.7%; a 40 µm thick i-layer with a doping concentration of 1E10 cm^− 3 under 30 µm of ¹⁴⁷Pm, resulting in an efficiency of 7.58%; a 30 µm thick i-layer with a doping concentration of 1E12 cm^− 3 under 70 µm of ¹⁴C, achieving an efficiency of 9.6%; a 3 µm thick i-layer with a doping concentration of 1E15 cm^− 3 under 1 µm of ³H with the lowest energy, which can obtain an efficiency of up to 30.7%. Due to the high energy density of ¹⁴⁷Pm, it can theoretically achieve a power density of 63 µW·cm^− 2. Ultimately, we propose the design of a one-third optimization strategy for high-performance diamond MIP Schottky betavoltaic cells.