Review—Extremely Thin Amorphous Indium Oxide Transistors

Abstract

Amorphous oxide semiconductor transistors have been a mature technology in display panels for upwards of a decade, and have recently been considered as promising back‐end‐of‐line (BEOL) compatible channel materials for monolithic 3D applications. However, achieving high‐mobility amorphous semiconductor materials with comparable performance to traditional crystalline semiconductors has been a long‐standing problem. Recently it has been found that greatly reducing the thickness of indium oxide, enabled by an atomic layer deposition (ALD) process, can tune its material properties to achieve high mobility, high drive current, high on/off ratio, and enhancement‐mode operation at the same time, beyond the capabilities of conventional oxide semiconductor materials. In this work, we review the history leading to the re‐emergence of indium oxide, its fundamental material properties, growth techniques with a focus on ALD, state‐of‐the‐art indium oxide device research, and the bias stability of the devices.This article is protected by copyright. All rights reserved

Sub-5 nm Ultrathin In2O3 Transistors for High-Performance and Low-Power Electronic Applications

“…Many techniques have been tried such as metalorganic chemical vapor deposition (MOCVD) and so on. 46 The ALD method is proven to be economically feasible with a low thermal budget, making large-area manufacturing of ultrathin In 2 O 3 FETs possible. Experimentally, the ultrathin In 2 O 3 FETs with various thicknesses and excellent performance have been successfully realized based on the ALD method.…”

“…For the sake of practical applications, it is highly desirable to grow high-quality ultrathin In 2 O 3 MOSFETs with repeatable thickness control. Many techniques have been tried such as metalorganic chemical vapor deposition (MOCVD) and so on . The ALD method is proven to be economically feasible with a low thermal budget, making large-area manufacturing of ultrathin In 2 O 3 FETs possible.…”

“…The ALD method is proven to be economically feasible with a low thermal budget, making large-area manufacturing of ultrathin In 2 O 3 FETs possible. Experimentally, the ultrathin In 2 O 3 FETs with various thicknesses and excellent performance have been successfully realized based on the ALD method. ,,,, Although ALD has shown many advantages in ultrathin device fabrication, some challenges still exist. As displayed in Figure , it is very important to align the top and bottom gates for the double-gated device.…”

Oxide and 2D TMD semiconductors for 3D DRAM cell transistors

“…Researchers have explored diverse compositional tuning to extend the application of OSs beyond a -IGZO, aiming to maximize mobility and to improve reliability. 21,22 Beyond IGZO, a variety of OSs with different combinations, including binary oxides (In 2 O 3 , ZnO), 23,24 ternary oxides (IGO, IZO), 25–27 and further combinations like IZTO 28 and IGZTO, 29 has been researched. It is noteworthy that the majority of research and development in the field of OS thin-film transistors (TFTs) has been directed towards their application in flat-panel displays, where the physical channel length tends to be longer, exceeding 1 μm.…”

Atomic Layer Deposition of WO3-Doped In2O3 for Reliable and Scalable BEOL-Compatible Transistors

“…Atomic layer deposition (ALD), in this context, excels by enabling excellent conformality of deposition on complex devices topographies, including steep side walls and deep trenches . Beyond its high conformality, ALD offers additional advantages of excellent wafer-scale thickness uniformity, atomically thin deposition, and smooth surfaces ideal for highly scaled devices, , ease of integration with ALD-grown dielectric layers, and minimal interface damage. These attributes combine to make ALD the preferred method for IWO film deposition for BEOL-compatible M3D devices.…”