Gate engineered heterostructure junctionless TFET with Gaussian doping profile for ambipolar suppression and electrical performance improvement

• Published in: Superlattices and microstructures Vol. 111; pp. 103 - 114
• Main Authors: Aghandeh, Hadi, Sedigh Ziabari, Seyed Ali
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2017
• Subjects: Ambipolar current; Gaussian doping; Heterostructure; Junctionless tunnel field-effect transistor; Heterostructure; Gaussian doping; Junctionless tunnel field-effect transistor; Ambipolar current
• ISSN: 0749-6036; 1096-3677
• DOI: 10.1016/j.spmi.2017.06.018

This study investigates a junctionless tunnel field-effect transistor with a dual material gate and a heterostructure channel/source interface (DMG-H-JLTFET). We find that using the heterostructure interface improves device behavior by reducing the tunneling barrier width at the channel/source interface. Simultaneously, the dual material gate structure decreases ambipolar current by increasing the tunneling barrier width at the drain/channel interface. The performance of the device is analyzed based on the energy band diagram at on, off, and ambipolar states. Numerical simulations demonstrate improvements in ION, IOFF, ION/IOFF, subthreshold slope (SS), transconductance and cut-off frequency and suppressed ambipolar behavior. Next, the workfunction optimization of dual material gate is studied. It is found that if appropriate workfunctions are selected for tunnel and auxiliary gates, the JLTFET exhibits considerably improved performance. We then study the influence of Gaussian doping distribution at the drain and the channel on the ambipolar performance of the device and find that a Gaussian doping profile and a dual material gate structure remarkably reduce ambipolar current. Gaussian doped DMG-H-JLTFET, also exhibits enhanced IOFF, ION/IOFF, SS and a low threshold voltage without degrading IOFF. •Junctionless tunnel field-effect transistor with a dual material gate and a heterostructure channel/source interface (DMG-H-JLTFET) have introduced.•The heterostructure interface improves device behavior by reducing the tunneling barrier width at the channel/source interface. Simultaneously, the dual material gate structure decreases IAMB.•Numerical simulations demonstrate improvements in ION, IOFF, ION/IOFF, subthreshold slope (SS), gm and fT and suppressed ambipolar behavior.•This paper demonstrates that Gaussian doping distribution reduce IAMB. Gaussian doped DMG-H-JLTFET, also exhibits enhanced IOFF, ION/IOFF, SS and a low VT without degrading IOFF.