Atomically Thin Indium-Tin-Oxide Transistors Enabled by Atomic Layer Deposition

High-Performance Thin-Film Transistor with Atomic Layer Deposition (ALD)-Derived Indium–Gallium Oxide Channel for Back-End-of-Line Compatible Transistor Applications: Cation Combinatorial Approach

“…Furthermore, advantages such as moderate field-effect mobility (μ FE ), low off-current down to 10 –24 A/μm, wide band gap of ∼3.2 eV, and its low-temperature processing capability (∼400 °C) makes O/S a promising candidate for back-end-of-line (BEOL) compatible transistors for logic, memory, and monolithic 3D integrated devices. For these reasons, O/S composition systems such as IGZO, − indium gallium oxide (IGO), − In 2 O 3 , − indium tin oxide (ITO), , etc., based on the ALD technique, have been studied recently, including the examination of suitability as a channel layer for several O/S substances. However, less is known regarding the design or feasibility of short-channel (<submicrometer scale) O/S TFTs on the basis of the following natural length (λ): , λ = t b t ox ε b ε ox where λ is the natural length that determines the transistor size, t b and t ox are the thicknesses of the body channel and GI layer, respectively, and ε b and ε ox are the dielectric constants of the body channel and gate insulator (GI) layer, respectively.…”

Atomic Layer Deposition of Metal Oxides and Chalcogenides for High Performance Transistors

“…A unique approach accessible only using ALD applies the standard half‐reaction protocol, but includes an additional separate half‐reaction with a different metal precursor during the growth cycle. [ 97 ] For example, alternating bilayers of In 2 O 3 and ZnO were deposited according to a fixed ratio of 0.6 (6:4 half‐reactions per cycle, respectively), resulting in a pseudo‐multinary semiconducting heterostructure. [ 137 ] Furthermore, selective deposition of the initial In 2 O 3 layer onto the dielectric interface significantly improves TFT performance in comparison to a reverse ZnO‐first architecture.…”

Ilmenite and amorphous SnTiO3 as p-type oxide semiconductors

“…[1][2][3][4] Recently, they have been proposed as back-end-of-line (BEOL) compatible transistor channel materials for implementing vertical CMOS technology. [5][6][7] Until now most available oxide semiconductors have been n-type oxides, for instance, In 2 O 3 , ITO, and IGZO, whereas their p-type counterparts remain scarce. This dominance of n-type oxides is because of the fundamental electronic structures associated with oxides: the top valence bands in typical oxides are dominated by deep-lying (8)(9) eV below the vacuum level) and localized oxygen-2p orbitals which result in limited hole mobility and hole doping.…”