Analysis of nanometer vacuum gap formation in thermo-tunneling devices

Combined thermionic emission and tunneling of hot electrons (thermo-tunneling) has emerged as a potential new solid-state cooling technology. Practical implementation of thermo-tunneling, however, requires the formation of a nanometer-sized gap spanning macroscopically significant surfaces. This paper describes a numerical and experimental investigation into the formation of a nanometer-sized tunneling gap based on the combined action of electrostatic, elastic and Lorentz forces. Experimental data reported here were used to tune the model and extract estimates for the size of the tunneling area and the gap size, respectively. The effect of changing the strength of the magnetic field was also investigated. The presented one-dimensional (1D) analysis of the relative magnitudes of these forces indicates possible stable operation.