Impact of Doping and Spacer on the Performance of Bulk Planar Junctionless devices

Abstract

In this paper the impact of spacer, and substrate doping concentration on ION, IOFF, $\mathbf{I}_{\mathbf{ON}}/\mathbf{I}_{\mathbf{OFF}}$, and unity gain frequency $(\mathbf{f}_{\mathbf{T}})$ of bulk junctionless planar transistor (BPJLT) is studied. Since these parameters affect the device ON and OFF currents, the studies are done by (i) constraining ON current (ii) constraining OFF current and (iii) without constraint. It is found that higher channel doping and lower substrate doping result in higher ION. Also lower channel doping and higher substrate doping gives lower IOFF. Better $\mathbf{I}_{\mathbf{ON}}/\mathbf{I}_{\mathbf{OFF}}$ ratio is achieved with heavy substrate and channel concentrations. Better $\mathbf{f}_{\mathbf{T}}$ and $\mathbf{I}_{\mathbf{ON}}/\mathbf{I}_{\mathbf{OFF}}$ ratio can be achieved at lower spacer lengths with ION constraint, using high K spacers.