Quantum dot cellular automata (QCA) have become a strong alternative for nanoscale computing. After a decade of exhaustive research on binary QCA, the newly introduced ternary QCA (tQCA) for implementing ternary logic needs further research to actually fabricate the tQCA cell. In this Letter, a quantum mechanical approach is presented for calculating the diverse parameters required for the fabrication of the tQCA. The effect of quantum dot size, the size of tQCA cell as well as the effect of temperature on polarisation for the tQCA cell are examined. The significant result for fabrication of the tQCA cell is tunnelling resistance, which must be greater than the quantum Hall resistance, that is, Rt> 25.813 kΩ. The tQCA needs a quantum dot size which is <6.36 nm to operate at room temperature and the distance of separation between two dots must be 5 nm. The steady-state behaviour of the tQCA cell using the Hubbard model and the Schrödinger timeindependent equation is also explored. © The Institution of Engineering and Technology 2013.