Bilayer TeO₂: The First Predicted Oxide Semiconductor with Symmetric Sub-5-nm NMOS and PMOS

Area of Science:

• Materials Science
• Condensed Matter Physics
• Semiconductor Device Physics

Background:

• Wide-band-gap oxide semiconductors are crucial for next-generation electronics, offering advantages like large-area manufacturing and low leakage.
• The lack of ultrashort-gate-length (Lg) p-type transistors has hindered their integration into complementary metal oxide semiconductor (CMOS) technology.
• Bilayer (BL) β-tellurium dioxide (β-TeO2) has emerged as a promising material with high hole mobility.

Purpose of the Study:

• To investigate the performance of sub-5nm Lg BL β-TeO2 field-effect transistors (FETs).
• To assess the potential of BL β-TeO2 for future CMOS applications.
• To explore the anisotropic transport properties of BL β-TeO2.

Main Methods:

• First-principles quantum transport simulations were employed to analyze BL β-TeO2 FETs.
• The study focused on devices with gate lengths (Lg) below 5 nm.
• Anisotropic transport characteristics in different crystallographic directions (x and y) were examined.

Main Results:

• Sub-5nm Lg n-type and p-type BL β-TeO2 FETs in the y-direction meet International Technology Roadmap for Semiconductors (ITRS) criteria for high-performance (HP) devices.
• For the first time, NMOS and PMOS symmetry was demonstrated in sub-5nm Lg oxide semiconductor FETs.
• In the x-direction, n-type BL β-TeO2 FETs satisfy both ITRS HP and low-power (LP) requirements down to 3nm Lg.

Conclusions:

• BL β-TeO2 exhibits excellent potential for CMOS applications due to its remarkable electronic properties.
• The demonstrated NMOS and PMOS symmetry in ultrashort-channel oxide FETs opens new avenues for device design.
• This research highlights BL β-TeO2 as a viable candidate for high-performance and low-power electronic devices.