Ab Initio Device-Driven Screening of Sub-1-nm Thickness Oxide Semiconductors for Future CMOS Technology Nodes

TL;DR

This paper introduces a computational workflow to identify ultrathin oxide semiconductors suitable for future CMOS transistors, highlighting CaO and SrO as promising p-type materials capable of scaling below 5 nm.

Contribution

It develops an ab initio, device-driven screening method to find sub-1-nm oxide semiconductors, revealing CaO and SrO as first-of-kind materials meeting CMOS criteria for both n- and p-type devices.

Findings

CaO and SrO are compatible with p-type FET operations.

CaO and SrO can meet ITRS high-performance and low-power criteria.

CaO and SrO FETs outperform many existing low-dimensional semiconductors.

Abstract

Ultrathin oxide semiconductors with sub-1-nm thickness are promising building blocks for ultrascaled field-effect transistor (FET) applications due to their resilience against short-channel effects, high air stability, and potential for low-energy device operation. However, the n-type dominance of ultrathin oxide FET has hindered their integration into complementary metal-oxide-semiconductor (CMOS) technology, which requires both n-and p-type devices. Here we develop an ab initio device-driven computational screening workflow to identify sub-1-nm thickness oxide semiconductors for sub-5-nm FET applications. We demonstrate that ultrathin CaO2, CaO, and SrO are compatible with p-type device operations under both high-performance (HP) and low-power (LP) requirements specified by the International Technology Roadmap of Semiconductors (ITRS), thereby expanding the limited family of p-type oxide semiconductors. Notably, CaO and SrO emerge as the first-of-kind sub-1-nm thickness oxide semiconductors capable of simultaneously meeting the ITRS HP and LP criteria for both n-and p-type devices. CaO and SrO FETs outperform many existing low-dimensional semiconductors, exhibiting scalability below 5-nm gate length. Our findings offer a pioneering effort in the ab initio, device-driven screening of sub-1-nm thickness oxide semiconductors, significantly broadening the material candidate pool for future CMOS technology nodes.