Atomic Layer Deposited Electron Transport Layers in Efficient Organometallic Halide Perovskite Devices

MRS Advances ◽  
2018 ◽  
Vol 3 (51) ◽  
pp. 3075-3084 ◽  
Author(s):  
Melissa M. McCarthy ◽  
Arnaud Walter ◽  
Soo-Jin Moon ◽  
Nakita K. Noel ◽  
Shane O’Brien ◽  
...  
Keyword(s):  
Thin Films ◽  
Electron Transport ◽  
Photoelectron Spectroscopy ◽  
Growth Parameters ◽  
Power Conversion ◽  
Perovskite Solar Cells ◽  
Atomic Layer ◽  
X Ray ◽  
Layer Deposition ◽  
Halide Perovskite

ABSTRACTAmorphous TiO2 and SnO2 electron transport layers (ETLs) were deposited by low-temperature atomic layer deposition (ALD). Surface morphology and x-ray photoelectron spectroscopy (XPS) indicate uniform and pinhole free coverage of these ALD hole blocking layers. Both mesoporous and planar perovskite solar cells were fabricated based on these thin films with aperture areas of 1.04 cm2 for TiO2 and 0.09 cm2 and 0.70 cm2 for SnO2. The resulting cell performance of 18.3 % power conversion efficiency (PCE) using planar SnO2 on 0.09 cm2 and 15.3 % PCE using mesoporous TiO2 on 1.04 cm2 active areas are discussed in conjunction with the significance of growth parameters and ETL composition.

scholarly journals Growth of lithium hydride thin films from solutions: Towards solution atomic layer deposition of lithiated films

2019 ◽  
Vol 10 ◽  
pp. 1443-1451
Author(s):  
Ivan Kundrata ◽  
Karol Fröhlich ◽  
Lubomír Vančo ◽  
Matej Mičušík ◽  
Julien Bachmann
Keyword(s):  
Thin Films ◽  
Atomic Layer Deposition ◽  
Surface Area ◽  
Photoelectron Spectroscopy ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Atomic Layer ◽  
Lithium Hydride ◽  
X Ray ◽  
Layer Deposition

Lithiated thin films are necessary for the fabrication of novel solid-state batteries, including the electrodes and solid electrolytes. Physical vapour deposition and chemical vapour deposition can be used to deposit lithiated films. However, the issue of conformality on non-planar substrates with large surface area makes them impractical for nanobatteries the capacity of which scales with surface area. Atomic layer deposition (ALD) avoids these issues and is able to deposit conformal films on 3D substrates. However, ALD is limited in the range of chemical reactions, due to the required volatility of the precursors. Moreover, relatively high temperatures are necessary (above 100 °C), which can be detrimental to electrode layers and substrates, for example to silicon into which the lithium can easily diffuse. In addition, several highly reactive precursors, such as Grignard reagents or n-butyllithium (BuLi) are only usable in solution. In theory, it is possible to use BuLi and water in solution to produce thin films of LiH. This theoretical reaction is self-saturating and, therefore, follows the principles of solution atomic layer deposition (sALD). Therefore, in this work the sALD technique and principles have been employed to experimentally prove the possibility of LiH deposition. The formation of homogeneous air-sensitive thin films, characterized by using ellipsometry, grazing incidence X-ray diffraction (GIXRD), in situ quartz crystal microbalance, and scanning electron microscopy, was observed. Lithium hydride diffraction peaks have been observed in as-deposited films by GIXRD. X-ray photoelectron spectroscopy and Auger spectroscopy analysis show the chemical identity of the decomposing air-sensitive films. Despite the air sensitivity of BuLi and LiH, making many standard measurements difficult, this work establishes the use of sALD to deposit LiH, a material inaccessible to conventional ALD, from precursors and at temperatures not suitable for conventional ALD.

The Growth of Tantalum Thin Films by Plasma-Enhanced Atomic Layer Deposition and Diffusion Barrier Properties

2002 ◽  
Vol 716 ◽  
Author(s):  
H. Kim ◽  
C. Cabral ◽  
C. Lavoie ◽  
S.M. Rossnagel
Keyword(s):  
Thin Films ◽  
Aspect Ratio ◽  
Atomic Layer Deposition ◽  
Diffusion Barrier ◽  
Growth Parameters ◽  
Atomic Layer ◽  
Barrier Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Layer Deposition

AbstractTa films were grown by plasma-enhanced atomic layer deposition (PE-ALD) at temperatures from room temperature up to 300 °C using TaCl5 as source gas and RF plasma-produced atomic H as the reducing agent. Post-deposition ex situ chemical analyses showed that the main impurity is oxygen, incorporated during the air exposure prior to analysis with typically low Cl concentration below 1 at %. The X-ray diffraction indicates that ALD Ta films are amorphous or composed of nano-grains. The typical resistivity of ALD Ta films was 150-180 μΩ cm, which corresponds to that of β-Ta phase, at a wide range of growth parameters. The conformality of the film is 100 % up to an aspect ratio of 15:1 and 40 % for aspect ratio of 40:1. The thickness per cycle, corresponding to the growth rate, was measured by Rutherford back scattering as a function of various key growth parameters, including TaCl5 and H exposure time and growth temperature. The maximum thickness per cycle values were below 0.1 ML, probably due to the steric hindrance for TaCl5 adsorption. Bilayer structures consisting of Cu films deposited by sputtering and ALD Ta films with various thicknesses were prepared and the diffusion barrier properties of ALD Ta films were investigated by various analysis techniques consisting of X-ray diffraction, elastic light scattering, and resistance analysis. The results were compared with Ta thin films deposited by sputtering with comparable thicknesses. Also, the growth of TaN films by PE-ALD using consecutive exposures of atomic H and activated N2 is presented.

scholarly journals Plasma Enhanced Atomic Layer Deposition of Tantalum (V) Oxide

Coatings ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1206
Author(s):  
Pavel Fedorov ◽  
Denis Nazarov ◽  
Oleg Medvedev ◽  
Yury Koshtyal ◽  
Aleksander Rumyantsev ◽  
...  
Keyword(s):  
Thin Films ◽  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Protective Coatings ◽  
Lithium Ion ◽  
Atomic Layer ◽  
Evaporator Temperature ◽  
Current Increase ◽  
X Ray ◽  
Layer Deposition

The tantalum oxide thin films are promising materials for various applications: as coatings in optical devices, as dielectric layers for micro and nanoelectronics, and for thin-films solid-state lithium-ion batteries (SSLIBs). This article is dedicated to the Ta-O thin-film system synthesis by the atomic layer deposition (ALD) which allows to deposit high quality films and coatings with excellent uniformity and conformality. Tantalum (V) ethoxide (Ta(OEt)5) and remote oxygen plasma were used as tantalum-containing reagent and oxidizing co-reagent, respectively. The influence of deposition parameters (reactor and evaporator temperature, pulse and purge times) on the growth rate were studied. The thickness of the films were measured by spectroscopic ellipsometry, scanning electron microscopy and X-ray reflectometry. The temperature range of the ALD window was 250–300 °C, the growth per cycle was about 0.05 nm/cycle. Different morphology of films deposited on silicon and stainless steel was found. According to the X-ray diffraction data, the as-prepared films were amorphous. But the heat treatment study shows crystallization at 800 °C with the formation of the polycrystalline Ta2O5 phase with a rhombic structural type (Pmm2). The results of the X-ray reflectometry show the Ta-O films’ density is 7.98 g/cm3, which is close to the density of crystalline Ta2O5 of the rhombic structure (8.18 g/cm3). The obtained thin films have a low roughness and high uniformity. The chemical composition of the surface and bulk of Ta-O coatings was studied by X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy. Surface of the films contain Ta2O5 and some carbon contamination, but the bulk of the films does not contain carbon and any precursor residues. Cyclic voltammetry (CVA) showed that there is no current increase for tantalum (V) oxide in a potential window of 3–4.2 V and has prospects of use as protective coatings for cathode materials of SSLIBs.

Spectroscopic study of La2O3 thin films deposited by indigenously developed plasma-enhanced atomic layer deposition system

2018 ◽  
Vol 32 (19) ◽  
pp. 1840074 ◽  
Author(s):  
Viral Barhate ◽  
Khushabu Agrawal ◽  
Vilas Patil ◽  
Sumit Patil ◽  
Ashok Mahajan
Keyword(s):  
Thin Films ◽  
Atomic Layer Deposition ◽  
Spectroscopic Study ◽  
Photoelectron Spectroscopy ◽  
Atomic Layer ◽  
X Ray Diffraction ◽  
Cross Sectional ◽  
X Ray ◽  
Transmission Electron ◽  
Layer Deposition

The spectroscopic study of La2O3 thin films deposited over Si and SiC at low RF power of 25 W by using indigenously developed plasma-enhanced atomic layer deposition (IDPEALD) system has been investigated. The tris (cyclopentadienyl) lanthanum (III) and O2 plasma were used as a source precursor of lanthanum and oxygen, respectively. The [Formula: see text]1.2 nm thick La2O3 over SiC and Si has been formed based on our recipe confirmed by means of cross-sectional transmission electron microscopy. The structural characterization of deposited films was performed by means of X-ray photoelectron Spectroscopy (XPS) and X-ray Diffraction (XRD). The XPS result confirms the formation of 3[Formula: see text] oxidation state of the lanthania. The XRD results reveals that, deposited La2O3 films deposited on SiC are amorphous in nature compare to that of films on Si. The AFM micrograph shows the lowest roughness of 0.26 nm for 30 cycles of La2O3 thin films.

A thiourea additive-based quadruple cation lead halide perovskite with an ultra-large grain size for efficient perovskite solar cells

Nanoscale ◽  
2019 ◽  
Vol 11 (45) ◽  
pp. 21824-21833 ◽  
Author(s):  
Jyoti V. Patil ◽  
Sawanta S. Mali ◽  
Chang Kook Hong
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Solar Cells ◽  
Power Conversion Efficiency ◽  
Conversion Efficiency ◽  
Power Conversion ◽  
Perovskite Solar Cells ◽  
Inorganic Perovskite ◽  
Halide Perovskite ◽  
Lead Halide

Controlling the grain size of the organic–inorganic perovskite thin films using thiourea additives now crossing 2 μm size with >20% power conversion efficiency.

scholarly journals Surface Passivation of Organometal Halide Perovskite by Atomic Layer Deposition: a Mechanism Investigation Enabling Efficient Inverted Planar Solar Cells

2021 ◽  
Author(s):  
Ran Zhao ◽  
Kai Zhang ◽  
Jiahao Zhu ◽  
Shuang Xiao ◽  
Wei Xiong ◽  
...  
Keyword(s):  
Solar Cells ◽  
Atomic Layer Deposition ◽  
High Efficiency ◽  
Surface Passivation ◽  
Perovskite Solar Cells ◽  
Wide Band ◽  
Atomic Layer ◽  
Layer Deposition ◽  
Halide Perovskite ◽  
Interface Passivation

Interface passivation is of the pivot to achieve high-efficiency organic metal halide perovskite solar cells (PSCs). Atomic layer deposition (ALD) of wide band gap oxides has recently shown great potential...

Use of anti-solvent to enhance thermoelectric response of hybrid-halide perovskite thin films

2022 ◽  
Author(s):  
Shrikant SAINI ◽  
Izuki Matsumoto ◽  
Sakura Kishishita ◽  
Ajay Kumar Baranwal ◽  
Tomohide Yabuki ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Conductivity ◽  
Photoelectron Spectroscopy ◽  
High Performance ◽  
Cost Effective ◽  
Performance Tuning ◽  
Charge Carrier Density ◽  
X Ray ◽  
Thermoelectric Energy Harvesting ◽  
Halide Perovskite

Abstract Hybrid halide perovskite has been recently focused on thermoelectric energy harvesting due to the cost-effective fabrication approach and ultra-low thermal conductivity. To achieve high performance, tuning of electrical conductivity is a key parameter that is influenced by grain boundary scattering and charge carrier density. The fabrication process allows tuning these parameters. We report the use of anti-solvent to enhance the thermoelectric performance of lead-free hybrid halide perovskite, CH3NH3SnI3, thin films. Thin films with anti-solvent show higher connectivity in grains and higher Sn+4 oxidation states which results in enhancing the value of electrical conductivity. Thin films were prepared by a cost-effective wet process. Structural and chemical characterizations were performed using x-ray diffraction, scanning electron microscope, and x-ray photoelectron spectroscopy. The value of electrical conductivity and the Seebeck coefficient were measured near room temperature. The high value of power factor (1.55 µW/m.K2 at 320 K) was achieved for thin films treated with anti-solvent.

scholarly journals Nucleation Studies of HfO2 Thin Films Produced by Atomic Layer Deposition

2007 ◽  
Vol 996 ◽  
Author(s):  
Justin C. Hackley ◽  
J. Derek Demaree ◽  
Theodosia Gougousi
Keyword(s):  
Thin Films ◽  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Flow Reactor ◽  
Atomic Layer ◽  
Sample Surface ◽  
Interfacial Region ◽  
Initial Growth ◽  
Layer Deposition ◽  
Similar Growth

AbstractA hot wall Atomic Layer Deposition (ALD) flow reactor equipped with a Quartz Crystal Microbalance (QCM) has been used for the deposition of HfO2 thin films with tetrakis (dimethylamino) hafnium (TDMAH) and H2O as precursors. HfO2 films were deposited on H-terminated Si and SC1 chemical oxide starting surfaces. Spectroscopic ellipsometry (SE) and QCM measurements confirm linear growth of the films at a substrate temperature of 275°C. FTIR spectra indicate the films are amorphous as-deposited. Two distinct growth regimes are observed: from 1-50 cycles, both surfaces display similar growth rates of about 1.0Å/cycle; from 50-200 cycles, HfO2 growth is decreased by about 15% to ~0.87Å/cycle on both surfaces. Nucleation and initial growth behavior of the films on Si-H were examined using X-ray photoelectron spectroscopy (XPS). Angle-resolved XPS, at take-off angles of θ=0, 15, 30, 45 and 60° measured from the normal to the sample surface, is used to probe the interfacial region of thin films (4, 7, 10, 15 and 25 cycles) on H-terminated samples. Initially, an interfacial layer comprised of a SiOx/HfSiOx mixture is grown between 1-10 ALD cycles. We observe that the Si/HfO2 interface is unstable, and oxidation continues up to the 25th ALD cycle, reaching a thickness of ~18Å.

Sign in / Sign up

Export Citation Format

Share Document