Performance projection of III‐nitride heterojunction nanowire tunneling field‐effect transistors

Abstract

The device concept and simulated characteristics of III‐nitride nanowire tunneling field‐effect transistors (NW TFETs) are presented. These devices employ polarization engineering in GaN/InN/GaN heterojunctions to achieve appreciable interband tunneling current densities, combined with a nanowire cylindrical gate‐all‐around geometry to achieve a high degree of gate electrostatic control. Simulations indicate that III‐nitride nanowire TFETs can be expected to achieve on–off current ratios of 1011, IOFF of 10−10 µA µm−1, sub‐threshold slopes as low as 25 mV dec−1 over 4 decades of current, and an ION of 50 µA µm−1 at a supply voltage of 0.5 V. A parametric evaluation of the geometry dependence of the device performance is performed, and the optimal device design parameter ranges for III‐nitride NW TFETs are identified.

A polarization-induced InN-based tunnel FET without physical doping

“…Based on the local neutralization principle, holes are consequently induced to neutralize these negative bound sheet charges, which thus forms the P-type doping of source region. Although there is some degradation of hole Actually, in some novel III-nitride heterojunction TFETs with physical doping source and drain [21,23,36], the polarization-induced technique has been used to enhance the doping concentration in the part of source region near the gate, based on which the on-state current and turn-on characteristics could be improved significantly. These reports could also demonstrate the effectiveness and potential of polarization-induced technique in realizing the doping of TFETs to a degree.…”

“…Recently, the III-Nitride-based materials, such as InN and InGaN, have gained a lot of interest in TFETs because of the small electron effective mass and moderate bandgap of the channel material [18]. Remarkable improvement of device performance in TFETs with III-Nitride materials have been achieved compared with the conventional Si-based counterparts [19][20][21][22][23][24]. However, most of the current III-Nitride-based TFETs are based on the physical doping technique, which means they may also suffer from the same problems as the conventional physical doping Si-based TFETs.…”

Bilateral sidewall engineering Si1–x Ge x iTFET for low power display application *

“…Although traditional TFET have advantages, they are rarely used in practical applications due to low on-current and large subthreshold swing, mainly due to the low probability of band-to-band tunneling using the traditional point tunneling approach and the severe impact of trap-assisted tunneling effects [9]. To overcome the limitations of traditional TFET, several novel TFET structures have been proposed, including highdrain doping [10], nanowire [11], multi-gate [12], and heterojunction structures [13][14][15][16]. We envision the integration of TFET into TFT applications.…”

Vertical polarization-induced doping InN/InGaN heterojunction tunnel FET with hetero T-shaped gate*

“…[8][9][10][11][12] Recently, various dopingless TFETs have been proposed based on the chargeplasma concept, [13][14][15][16] which demonstrates an effective way to realize TFETs without physical doping. And based on the po-larization effect near III-nitride-based heterointerfaces, [17][18][19][20][21] the lateral polarization-induced InN-based TFETs (PI-InN-TFET) have been demonstrated by our group. [22] This also opens a new path to the further development of TFETs without physical doping processing.…”