scholarly journals Wafer-Scale Synthesis of WS2 Films with In Situ Controllable p-Type Doping by Atomic Layer Deposition

Research ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Hanjie Yang ◽  
Yang Wang ◽  
Xingli Zou ◽  
Rongxu Bai ◽  
Zecheng Wu ◽  
...  
Keyword(s):  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Hole Mobility ◽  
Atomic Layer ◽  
Cycle Number ◽  
Wafer Scale ◽  
Layer Deposition ◽  
Nb Doping ◽  
P Type

Wafer-scale synthesis of p-type TMD films is critical for its commercialization in next-generation electro/optoelectronics. In this work, wafer-scale intrinsic n-type WS2 films and in situ Nb-doped p-type WS2 films were synthesized through atomic layer deposition (ALD) on 8-inch α-Al2O3/Si wafers, 2-inch sapphire, and 1 cm2 GaN substrate pieces. The Nb doping concentration was precisely controlled by altering cycle number of Nb precursor and activated by postannealing. WS2 n-FETs and Nb-doped p-FETs with different Nb concentrations have been fabricated using CMOS-compatible processes. X-ray photoelectron spectroscopy, Raman spectroscopy, and Hall measurements confirmed the effective substitutional doping with Nb. The on/off ratio and electron mobility of WS2 n-FET are as high as 105 and 6.85 cm2 V-1 s-1, respectively. In WS2 p-FET with 15-cycle Nb doping, the on/off ratio and hole mobility are 10 and 0.016 cm2 V-1 s-1, respectively. The p-n structure based on n- and p- type WS2 films was proved with a 104 rectifying ratio. The realization of controllable in situ Nb-doped WS2 films paved a way for fabricating wafer-scale complementary WS2 FETs.

scholarly journals Structural and Optical Properties of Luminescent Copper(I) Chloride Thin Films Deposited by Sequentially Pulsed Chemical Vapour Deposition

Coatings ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 369 ◽  
Author(s):  
Richard Krumpolec ◽  
Tomáš Homola ◽  
David Cameron ◽  
Josef Humlíček ◽  
Ondřej Caha ◽  
...  
Keyword(s):  
Atomic Layer Deposition ◽  
Chemical Vapour Deposition ◽  
Photoelectron Spectroscopy ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Atomic Layer ◽  
Nanocrystalline Films ◽  
Zinc Blende ◽  
Layer Deposition

Sequentially pulsed chemical vapour deposition was used to successfully deposit thin nanocrystalline films of copper(I) chloride using an atomic layer deposition system in order to investigate their application to UV optoelectronics. The films were deposited at 125 °C using [Bis(trimethylsilyl)acetylene](hexafluoroacetylacetonato)copper(I) as a Cu precursor and pyridine hydrochloride as a new Cl precursor. The films were analysed by XRD, X-ray photoelectron spectroscopy (XPS), SEM, photoluminescence, and spectroscopic reflectance. Capping layers of aluminium oxide were deposited in situ by ALD (atomic layer deposition) to avoid environmental degradation. The film adopted a polycrystalline zinc blende-structure. The main contaminants were found to be organic materials from the precursor. Photoluminescence showed the characteristic free and bound exciton emissions from CuCl and the characteristic exciton absorption peaks could also be detected by reflectance measurements.

scholarly journals Ambient pressure x-ray photoelectron spectroscopy setup for synchrotron-based in situ and operando atomic layer deposition research

2022 ◽  
Vol 93 (1) ◽  
pp. 013905
Author(s):  
E. Kokkonen ◽  
M. Kaipio ◽  
H.-E. Nieminen ◽  
F. Rehman ◽  
V. Miikkulainen ◽  
...  
Keyword(s):  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Ambient Pressure ◽  
Atomic Layer ◽  
X Ray ◽  
Layer Deposition

Initial and steady-state Ru growth by atomic layer deposition studied by in situ Angle Resolved X-ray Photoelectron Spectroscopy

2017 ◽  
Vol 419 ◽  
pp. 107-113 ◽  
Author(s):  
Konstantin V. Egorov ◽  
Yury Yu. Lebedinskii ◽  
Anatoly A. Soloviev ◽  
Anastasia A. Chouprik ◽  
Alexander Yu. Azarov ◽  
...  
Keyword(s):  
Steady State ◽  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Atomic Layer ◽  
X Ray ◽  
Layer Deposition

Properties of High-Quality LaAlO3 Film Deposited by In Situ Plasma-Enhanced-Atomic-Layer-Deposition

2013 ◽  
Vol 721 ◽  
pp. 24-28 ◽  
Author(s):  
Duo Cao ◽  
Xin Hong Cheng ◽  
Ting Ting Jia ◽  
Da Wei Xu ◽  
Li Zheng ◽  
...  
Keyword(s):  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Atomic Layer ◽  
Valence Band Offset ◽  
Xps Spectra ◽  
Transmission Electron ◽  
Layer Deposition ◽  
Interfacial States ◽  
Current Densities

Plasma enhanced atomic layer deposition (PEALD) method can decrease film growing temperature, and allow in-situ plasma treatment. LaAlO3 films were deposited with PEALD at 180°C. High resolution transmission electron microscopy (HRTEM) results exhibited amorphous microstructure of both films even after rapid thermal annealing (RTA) at 800°C. X-ray photoelectron spectroscopy (XPS) spectra suggested that the valence-band offset between the LaAlO3 film and the substrate was 3.3 eV. The electrical experimental results indicated that the leakage current densities were 0.10mA/cm2 and 0.03mA/cm2 respectively at a gate bias of |Vg-Vfb|=1V and the equivalent oxide thicknesses (EOT) of them were 1.2 nm and 1.4 nm, respectively. The densities of interfacial states were calculated to be 1.70×1012eV-1cm-2 and 1.09×1012eV-1cm-2, respectively.

Oxygen Vacancies at the γ-Al2O3/STO Heterointerface Grown by Atomic Layer Deposition

2015 ◽  
Vol 1730 ◽  
Author(s):  
Thong Q. Ngo ◽  
Martin D. McDaniel ◽  
Agham Posadas ◽  
Alexander A. Demkov ◽  
John G. Ekerdt
Keyword(s):  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Oxygen Vacancies ◽  
Atomic Layer ◽  
High Energy ◽  
Ex Situ ◽  
X Ray ◽  
Layer Deposition ◽  
Dimensional Electron Gas

ABSTRACTWe report the epitaxial growth of γ-Al2O3 on SrTiO3 (STO) substrates by atomic layer deposition (ALD). The ALD growth of γ-Al2O3 on STO(001) single crystal substrates was performed at a temperature of 345 °C. Trimethylaluminum and water were used as co-reactants. In-situ reflection high-energy electron diffraction and ex-situ x-ray diffraction were used to determine the crystallinity of the Al2O3 films. In-situ x-ray photoelectron spectroscopy was used to characterize the Al2O3/STO heterointerface. The formation of a Ti3+ feature is observed in the Ti 2p spectrum of STO after the first few ALD cycles of Al2O3 and even after exposure of the STO substrate to trimethylaluminum alone at 345 °C. The presence of a Ti3+ feature is a direct indication of oxygen vacancies at the Al2O3/STO heterointerface, which provide the carriers for the quasi-two dimensional electron gas at the interface.

scholarly journals High-κ Dielectric on ReS2: In-Situ Thermal Versus Plasma-Enhanced Atomic Layer Deposition of Al2O3

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1056 ◽  
Author(s):  
Ava Khosravi ◽  
Rafik Addou ◽  
Massimo Catalano ◽  
Jiyoung Kim ◽  
Robert Wallace
Keyword(s):  
Thin Film ◽  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Atomic Layer ◽  
Ex Situ ◽  
Half Cycle ◽  
Layer Deposition ◽  
Uv Ozone ◽  
Al2o3 Thin Film

We report an excellent growth behavior of a high-κ dielectric on ReS2, a two-dimensional (2D) transition metal dichalcogenide (TMD). The atomic layer deposition (ALD) of an Al2O3 thin film on the UV-Ozone pretreated surface of ReS2 yields a pinhole free and conformal growth. In-situ half-cycle X-ray photoelectron spectroscopy (XPS) was used to monitor the interfacial chemistry and ex-situ atomic force microscopy (AFM) was used to evaluate the surface morphology. A significant enhancement in the uniformity of the Al2O3 thin film was deposited via plasma-enhanced atomic layer deposition (PEALD), while pinhole free Al2O3 was achieved using a UV-Ozone pretreatment. The ReS2 substrate stays intact during all different experiments and processes without any formation of the Re oxide. This work demonstrates that a combination of the ALD process and the formation of weak S–O bonds presents an effective route for a uniform and conformal high-κ dielectric for advanced devices based on 2D materials.

Sign in / Sign up

Export Citation Format

Share Document