Controlled exposure of CuO thin films through corrosion-protecting, ALD-deposited TiO2 overlayers

Abstract Ultra-thin film coatings are used to protect semiconductor photoelectrodes from the harsh chemical environments common to photoelectrochemical energy conversion. These layers add contact transfer resistance to the interface that can result in a reduction of photoelectrochemical energy conversion efficiency of the photoelectrode. Here, we describe the concept of a partial protection layer, which allows for direct chemical access to a small fraction of the semiconductor underlayer for further functionalization by an electrocatalyst. The rest of the interface remains protected by a stable, inert protection layer. CuO is used as a model system for this scheme. Atomic layer deposition (ALD)-prepared TiO2 layers on CuO thin films prepared from electrodeposited Cu2O allow for the control of interfacial morphology to intentionally expose the CuO underlayer. The ALD-TiO2 overlayer shrinks during crystallization, while Cu2O in the underlayer expands during oxidation. As a result, the TiO2 protection layer cracks to expose the oxidized underlying CuO layer, which can be controlled by preceding thermal oxidation. This work demonstrates a potentially promising strategy for the parallel optimization of photoelectrochemical interfaces for chemical stability and high performance.

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Depositing High-Performance Conductive Thin Films by Using Atomic Layer Deposition

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.764-765.138 ◽

2015 ◽

Vol 764-765 ◽

pp. 138-142 ◽

Cited By ~ 1

Author(s):

Fa Ta Tsai ◽

Hsi Ting Hou ◽

Ching Kong Chao ◽

Rwei Ching Chang

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

High Performance ◽

Atomic Layer ◽

Electric Properties ◽

X Ray Diffraction ◽

Layer Deposition ◽

Azo Thin Film ◽

Aluminum Doped Zinc Oxide ◽

Conductive Thin Films

This work characterizes the mechanical and opto-electric properties of Aluminum-doped zinc oxide (AZO) thin films deposited by atomic layer deposition (ALD), where various depositing temperature, 100, 125, 150, 175, and 200 °C are considered. The transmittance, microstructure, electric resistivity, adhesion, hardness, and Young’s modulus of the deposited thin films are tested by using spectrophotometer, X-ray diffraction, Hall effect analyzer, micro scratch, and nanoindentation, respectively. The results show that the AZO thin film deposited at 200 °C behaves the best electric properties, where its resistance, Carrier Concentration and mobility reach 4.3×10-4 Ωcm, 2.4×1020 cm-3, and 60.4 cm2V-1s-1, respectively. Furthermore, microstructure of the AZO films deposited by ALD is much better than those deposited by sputtering.

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Characteristics Of SnSbSe (SSS) Thin Films Grown by Atomic Layer Deposition for High Performance Phase Change Random Access Memory (PCRAM)

ECS Meeting Abstracts ◽

10.1149/ma2013-01/22/904 ◽

2013 ◽

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

Phase Change ◽

High Performance ◽

Random Access ◽

Random Access Memory ◽

Atomic Layer ◽

Access Memory ◽

Layer Deposition

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Characteristics Of SnSbSe (SSS) Thin Films Grown by Atomic Layer Deposition for High Performance Phase Change Random Access Memory (PCRAM)

ECS Transactions ◽

10.1149/05306.0045ecst ◽

2013 ◽

Vol 53 (6) ◽

pp. 45-51 ◽

Cited By ~ 1

Author(s):

K. Lee ◽

S. Kang ◽

J. Ku ◽

K. Hong ◽

S. Park

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

Phase Change ◽

High Performance ◽

Random Access ◽

Random Access Memory ◽

Atomic Layer ◽

Access Memory ◽

Layer Deposition

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Characterization of ZnO Thin Films Fabricated by Atomic Layer Deposition with Various Temperatures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.650.18 ◽

2013 ◽

Vol 650 ◽

pp. 18-23 ◽

Cited By ~ 1

Author(s):

Tsai Cheng Li ◽

Rwei Ching Chang ◽

Pei Sin Jhu

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

High Performance ◽

Atomic Layer ◽

Zno Thin Films ◽

Zno Films ◽

Sputtered Films ◽

Layer Deposition ◽

Substrate Temperatures

Atomic layer deposition (ALD) is utilized to grow high performance zinc oxide (ZnO) thin films, where the effects of ALD process temperature on the thin film properties are also studied in this work. Some major properties of the ALD ZnO films are characterized and compared with those of sputtered ZnO films. Significant differences are observed that the electrical resistances of the ALD ZnO films are largely improved, while the optical transmittances also increase. Nevertheless, the adhesion and mechanical properties of the ALD films are worse than the sputtered films because of the weak bonding in the ALD process. For various substrate temperatures, the ALD ZnO films with 200°C behave the best performance.

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Synthesis of few-layer 2H-MoSe2 thin films with wafer-level homogeneity for high-performance photodetector

Nanophotonics ◽

10.1515/nanoph-2018-0153 ◽

2018 ◽

Vol 7 (12) ◽

pp. 1959-1969 ◽

Cited By ~ 11

Author(s):

Tian-Jun Dai ◽

Yu-Chen Liu ◽

Xu-Dong Fan ◽

Xing-Zhao Liu ◽

Dan Xie ◽

...

Keyword(s):

Thin Films ◽

High Performance ◽

Deep Understanding ◽

Chemical Vapor ◽

Atomic Layer ◽

Fast Response ◽

Wafer Level ◽

Large Area ◽

Carrier Recombination ◽

Layer Deposition

AbstractThe unique structural and physical properties of two-dimensional (2D) atomic layer semiconductors render them promising candidates for electronic or optoelectronic devices. However, the lack of efficient and stable approaches to synthesize large-area thin films with excellent uniformity hinders their realistic applications. In this work, we reported a method involving atomic layer deposition and a chemical vapor deposition chamber to produce few-layer 2H-MoSe2 thin films with wafer-level uniformity. The reduction of MoO3 was found indispensable for the successful synthesis of MoSe2 films due to the low vaporization temperature. Moreover, a metal-semiconductor-metal photodetector (PD) was fabricated and investigated systematically. We extracted an ultrahigh photoresponsivity approaching 101 A/W with concomitantly high external quantum efficiency up to 19,668% due to the produced gain arising from the holes trapped at the metal/MoSe2 interface, the band tail state contribution, and the photogating effect. A fast response time of 22 ms was observed and attributed to effective nonequilibrium carrier recombination. Additionally, the ultrahigh photoresponsivity and low dark current that originated from Schottky barrier resulted in a record-high specific detectivity of up to 2×1013 Jones for 2D MoSe2/MoS2 PDs. Our findings revealed a pathway for the development of high-performance PDs based on 2D MoSe2 that are inexpensive, large area, and suitable for mass production and contribute to a deep understanding of the photoconductivity mechanisms in atomically thin MoSe2. We anticipate that these results are generalizable to other layer semiconductors as well.

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On the Use of MOFs and ALD Layers as Nanomembranes for the Enhancement of Gas Sensors Selectivity

Nanomaterials ◽

10.3390/nano9111552 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1552 ◽

Cited By ~ 3

Author(s):

Weber ◽

Graniel ◽

Balme ◽

Miele ◽

Bechelany

Keyword(s):

Thin Films ◽

Gas Sensors ◽

Gas Sensing ◽

Metal Organic Frameworks ◽

Atomic Layer ◽

Operational Performance ◽

Layer Deposition ◽

Metal Organic ◽

Further Development ◽

Different Gases

Improving the selectivity of gas sensors is crucial for their further development. One effective route to enhance this key property of sensors is the use of selective nanomembrane materials. This work aims to present how metal-organic frameworks (MOFs) and thin films prepared by atomic layer deposition (ALD) can be applied as nanomembranes to separate different gases, and hence improve the selectivity of gas sensing devices. First, the fundamentals of the mechanisms and configuration of gas sensors will be given. A selected list of studies will then be presented to illustrate how MOFs and ALD materials can be implemented as nanomembranes and how they can be implemented to improve the operational performance of gas sensing devices. This review comprehensively shows the benefits of these novel selective nanomaterials and opens prospects for the sensing community.

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