Dual-material dual-oxide double-gate TFET for improvement in DC characteristics, analog/RF and linearity performance

To overcome the problem of fabrication complexity and to reducei the cost of microelectronic devices, a new concept of dual-material control gate with dual-oxide tunnel field-effect transistor is investigated. A stack gate approach is applied to reduce the width of tunneling barrier at source–channel junction. Use of dual oxides at source–channel interface provides improved capacitive coupling, which enhances the on-state current. The entire gate segment has been partitioned into three parts, namely tunnel gate $$(M_1)$$, control gate $$(M_2)$$ and auxiliary gate $$(M_3)$$ with different work functions such as $$\phi ₁$$, $$\phi ₂$$ and $$\phi ₃$$. In this context, to keep dual-work functionality, the feasible combinations of these work functions are adopted. Technology computer- aided design (TCAD) simulations of these proposed combinations of work functions along with dual oxides provide better results for the combinations of $$(\phi _1=\phi _3<\phi _2)$$. In addition, comparison between these combinations on the basis of analog/RF performance is done in this work. This work shows improved analog/RF parameters such as $$g_\text {m}, C_\text {gs}, C_\text {gd}, f_\text {T}$$ and TFP, and linearity parameters including $$g_\text {m3}, \text {VIP3, IIP3}$$ and $$\text {IMD3}$$ for the proposed device DMDODG-TFET (dual-material dual-oxide double-gate TFET). The use of this proposed device structure reduces the ambipolar behavior and subthreshold swing $$(18.5\,\text {mV}/\text {deacde})$$, and enhances the on-current [$$3.6\times 10^-5\,(A/\upmu \text {m})$$] significantly, making it suitable for analog/RF and linearity applications.