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1.
Molecules ; 26(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34443385

RESUMO

DNA origami nanostructures (DONs) are promising substrates for the single-molecule investigation of biomolecular reactions and dynamics by in situ atomic force microscopy (AFM). For this, they are typically immobilized on mica substrates by adding millimolar concentrations of Mg2+ ions to the sample solution, which enable the adsorption of the negatively charged DONs at the like-charged mica surface. These non-physiological Mg2+ concentrations, however, present a serious limitation in such experiments as they may interfere with the reactions and processes under investigation. Therefore, we here evaluate three approaches to efficiently immobilize DONs at mica surfaces under essentially Mg2+-free conditions. These approaches rely on the pre-adsorption of different multivalent cations, i.e., Ni2+, poly-l-lysine (PLL), and spermidine (Spdn). DON adsorption is studied in phosphate-buffered saline (PBS) and pure water. In general, Ni2+ shows the worst performance with heavily deformed DONs. For 2D DON triangles, adsorption at PLL- and in particular Spdn-modified mica may outperform even Mg2+-mediated adsorption in terms of surface coverage, depending on the employed solution. For 3D six-helix bundles, less pronounced differences between the individual strategies are observed. Our results provide some general guidance for the immobilization of DONs at mica surfaces under Mg2+-free conditions and may aid future in situ AFM studies.


Assuntos
Silicatos de Alumínio/química , DNA/química , Magnésio/química , Microscopia de Força Atômica , Nanoestruturas/química , Conformação de Ácido Nucleico , Adsorção , Níquel/química , Polieletrólitos/química , Polilisina/química , Espermidina/química , Propriedades de Superfície , Água/química
2.
Biomacromolecules ; 22(10): 4084-4094, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34410695

RESUMO

The natural blood protein fibrinogen is a highly potent precursor for the production of various biomaterials due to its supreme biocompatibility and cell interaction. To gain actual materials from fibrinogen, the protein needs to undergo fibrillogenesis, which is mostly triggered via enzymatic processing to fibrin, electrospinning, or drying processes. All of those techniques, however, strongly limit the available structures or the applicability of the material. To overcome the current issues of fibrin(ogen) as material, we herein present a highly feasible, quick, and inexpensive technique for self-assembly of fibrinogen in solution into defined, nanofibrous three-dimensional (3D) patterns. Upon interaction with specific anions in controlled environments, stable and flexible hydrogel-like structures are formed without any further processing. Moreover, the material can be converted into highly porous and elastic aerogels by lyophilization. Both of these material classes have never been described before from native fibrinogen. The observed phenomenon also represents the first enzyme-free process of fibrillogenesis from fibrinogen with significant yield in solution. The produced hydrogels and aerogels were investigated via electron microscopy, IR spectroscopy, and fluorescence spectroscopy, which also confirms the native state of the protein. Additionally, their mechanical properties were compared with actual fibrin and unstructured fibrinogen. The structural features show a striking analogy to actual fibrin, both as hydro- and aerogel. This renders the new material a highly promising alternative for fibrin in biomaterial applications. A much faster initiation of fiber formation, exclusion of possible thrombin residuals, and low-cost reagents are great advantages.

3.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34067963

RESUMO

The effects that solid-liquid interfaces exert on the aggregation of proteins and peptides are of high relevance for various fields of basic and applied research, ranging from molecular biology and biomedicine to nanotechnology. While the influence of surface chemistry has received a lot of attention in this context, the role of surface topography has mostly been neglected so far. In this work, therefore, we investigate the aggregation of the type 2 diabetes-associated peptide hormone hIAPP in contact with flat and nanopatterned silicon oxide surfaces. The nanopatterned surfaces are produced by ion beam irradiation, resulting in well-defined anisotropic ripple patterns with heights and periodicities of about 1.5 and 30 nm, respectively. Using time-lapse atomic force microscopy, the morphology of the hIAPP aggregates is characterized quantitatively. Aggregation results in both amorphous aggregates and amyloid fibrils, with the presence of the nanopatterns leading to retarded fibrillization and stronger amorphous aggregation. This is attributed to structural differences in the amorphous aggregates formed at the nanopatterned surface, which result in a lower propensity for nucleating amyloid fibrillization. Our results demonstrate that nanoscale surface topography may modulate peptide and protein aggregation pathways in complex and intricate ways.


Assuntos
Agonistas dos Receptores da Amilina/química , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Nanoestruturas/química , Agregados Proteicos , Humanos , Modelos Moleculares , Propriedades de Superfície
4.
J Biomed Mater Res B Appl Biomater ; 109(12): 2142-2153, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33982864

RESUMO

Photodynamic therapy (PDT) using TiO2 nanoparticles has become an important alternative treatment for different types of cancer due to their high photocatalytic activity and high absorption of UV-A light. To potentiate this treatment, we have coated commercial glass plates with TiO2 nanoparticles prepared by the sol-gel method (TiO2 -m), which exhibit a remarkable selectivity for the irreversible trapping of cancer cells. The physicochemical properties of the deposited TiO2 -m nanoparticle coatings have been characterized by a number of complementary surface-analytical techniques and their interaction with leukemia and healthy blood cells were investigated. Scanning electron and atomic force microscopy verify the formation of a compact layer of TiO2 -m nanoparticles. The particles are predominantly in the anatase phase and have hydroxyl-terminated surfaces as revealed by Raman, X-ray photoelectron, and infrared spectroscopy, as well as X-ray diffraction. We find that lymphoblastic leukemia cells adhere to the TiO2 -m coating and undergo amoeboid-like migration, whereas lymphocytic cells show distinctly weaker interactions with the coating. This evidences the potential of this nanomaterial coating to selectively trap cancer cells and renders it a promising candidate for the development of future prototypes of PDT devices for the treatment of leukemia and other types of cancers with non-adherent cells.

5.
Nanomaterials (Basel) ; 11(4)2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807354

RESUMO

In this work, the electrografting of Al-7075 aluminium alloy substrates with 4-nitrobenzenediazonium salt (4-NBD) films was studied on a complex aluminium alloy surface. Prior to the electrografting reaction, the substrates were submitted to different surface treatments to modify the native aluminium oxide layer and unveil intermetallic particles (IMPs). The formation of the 4-NBD films could be correlated with the passive film state and the distribution of IMPs. The corresponding electrografting reaction was performed by cyclic voltammetry which allowed the simultaneous analysis of the redox reaction by a number of complementary surface-analytical techniques. Spatially resolved thin film analysis was performed by means of SEM-EDX, AFM, PM-IRRAS, Raman spectroscopy, XPS, and SKPFM. The collected data show that the 4-NBD film is preferentially formed either on the Al oxide layer or the IMP surface depending on the applied potential range. Potentials between -0.1 and -1.0 VAg/AgCl mostly generated nitrophenylene films on the oxide covered aluminium, while grafting between -0.1 and -0.4 VAg/AgCl favours the growth of these films on IMPs.

6.
Chemistry ; 27(33): 8564-8571, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33780583

RESUMO

The surface-assisted hierarchical assembly of DNA origami nanostructures is a promising route to fabricate regular nanoscale lattices. In this work, the scalability of this approach is explored and the formation of a homogeneous polycrystalline DNA origami lattice at the mica-electrolyte interface over a total surface area of 18.75 cm2 is demonstrated. The topological analysis of more than 50 individual AFM images recorded at random locations over the sample surface showed only minuscule and random variations in the quality and order of the assembled lattice. The analysis of more than 450 fluorescence microscopy images of a quantum dot-decorated DNA origami lattice further revealed a very homogeneous surface coverage over cm2 areas with only minor boundary effects at the substrate edges. At total DNA costs of €â€…0.12 per cm2 , this large-scale nanopatterning technique holds great promise for the fabrication of functional surfaces.


Assuntos
Nanoestruturas , Nanotecnologia , DNA , Microscopia de Força Atômica , Conformação de Ácido Nucleico
7.
Adv Nanobiomed Res ; 1(2): 2170023, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33786537

RESUMO

Biointerfaces The cover image shows the adsorption of SARS-CoV-2 at metal-based fomite surfaces. The spike protein subunit S1 is the outermost point of the viral envelope and thus mediates the initial contact between the virus and the fomite surface. High-speed atomic force microscopy movies reveal that S1 protein adsorption proceeds faster at TiO2 surfaces than at Al2O3 surfaces. More details can be found in article number 2000024 by Adrian Keller and co-workers.

8.
Molecules ; 25(21)2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33153073

RESUMO

Immobile Holliday junctions represent not only the most fundamental building block of structural DNA nanotechnology but are also of tremendous importance for the in vitro investigation of genetic recombination and epigenetics. Here, we present a detailed study on the room-temperature assembly of immobile Holliday junctions with the help of the single-strand annealing protein Redß. Individual DNA single strands are initially coated with protein monomers and subsequently hybridized to form a rigid blunt-ended four-arm junction. We investigate the efficiency of this approach for different DNA/protein ratios, as well as for different DNA sequence lengths. Furthermore, we also evaluate the potential of Redß to anneal sticky-end modified Holliday junctions into hierarchical assemblies. We demonstrate the Redß-mediated annealing of Holliday junction dimers, multimers, and extended networks several microns in size. While these hybrid DNA-protein nanostructures may find applications in the crystallization of DNA-protein complexes, our work shows the great potential of Redß to aid in the synthesis of functional DNA nanostructures under mild reaction conditions.


Assuntos
DNA Cruciforme/química , DNA de Cadeia Simples/química , Proteínas de Ligação a DNA/química , DNA/química , Temperatura
9.
Nanomaterials (Basel) ; 10(11)2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33158138

RESUMO

The aggregation of human islet amyloid polypeptide (hIAPP) plays a major role in the pathogenesis of type 2 diabetes mellitus (T2DM), and numerous strategies for controlling hIAPP aggregation have been investigated so far. In particular, several organic and inorganic nanoparticles (NPs) have shown the potential to influence the aggregation of hIAPP and other amyloidogenic proteins and peptides. In addition to conventional NPs, DNA nanostructures are receiving more and more attention from the biomedical field. Therefore, in this work, we investigated the effects of two different DNA origami nanostructures on hIAPP aggregation. To this end, we employed in situ turbidity measurements and ex situ atomic force microscopy (AFM). The turbidity measurements revealed a retarding effect of the DNA nanostructures on hIAPP aggregation, while the AFM results showed the co-aggregation of hIAPP with the DNA origami nanostructures into hybrid peptide-DNA aggregates. We assume that this was caused by strong electrostatic interactions between the negatively charged DNA origami nanostructures and the positively charged peptide. Most intriguingly, the influence of the DNA origami nanostructures on hIAPP aggregation differed from that of genomic double-stranded DNA (dsDNA) and appeared to depend on DNA origami superstructure. DNA origami nanostructures may thus represent a novel route for modulating amyloid aggregation in vivo.

10.
Langmuir ; 36(32): 9489-9498, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32689801

RESUMO

The presented studies correlate the surface chemistry of electrochemically oxidized TiAlN hard coatings with the desorption forces of poly(acrylic acid) (PAA) at the electrolyte/oxide/TiAlN interface. Atomic force microscopy (AFM)-based single-molecule force spectroscopy (SMFS) was performed at different pH values to investigate surface chemistry-induced changes in desorption force. The chemical state was characterized by X-ray photoemission spectroscopy and electrochemical analysis. The results show that the desorption forces continuously decrease with increasing pH in the range from pH 5 to 9. The comparison of the desorption forces on rf-sputtered titanium dioxide and aluminum oxide films shows that the electrochemically oxidized surface of TiAlN, in agreement with the revealed surface composition, shows interfacial adhesive properties in contact with PAA and water that resemble a pure titanium oxide layer. Load rate-dependent measurements were performed to analyze both the free energy barrier and the transition state distance.

11.
Angew Chem Int Ed Engl ; 59(34): 14336-14341, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32485088

RESUMO

High-speed atomic force microscopy (HS-AFM) is widely employed in the investigation of dynamic biomolecular processes at a single-molecule level. However, it remains an open and somewhat controversial question, how these processes are affected by the rapidly scanned AFM tip. While tip effects are commonly believed to be of minor importance in strongly binding systems, weaker interactions may significantly be disturbed. Herein, we quantitatively assess the role of tip effects in a strongly binding system using a DNA origami-based single-molecule assay. Despite its femtomolar dissociation constant, we find that HS-AFM imaging can disrupt monodentate binding of streptavidin (SAv) to biotin (Bt) even under gentle scanning conditions. To a lesser extent, this is also observed for the much stronger bidentate SAv-Bt complex. The presented DNA origami-based assay can be universally employed to quantify tip effects in strongly and weakly binding systems and to optimize the experimental settings for their reliable HS-AFM imaging.


Assuntos
DNA/metabolismo , Microscopia de Força Atômica/métodos , Imagem Individual de Molécula/métodos , Proteínas de Bactérias/química , Biotina/análogos & derivados , Biotina/química , DNA/química , Ligantes , Nanoestruturas/química
12.
Nanoscale ; 12(17): 9733-9743, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32324191

RESUMO

The surface-assisted hierarchical assembly of DNA nanostructures into regular lattices is not only a promising route toward the fabrication of molecular lithography masks over macroscopic surface areas, but also represents an intriguing model system that enables the direct real-time observation of interface-related dynamic phenomena such as adsorption, desorption, and diffusion that are hardly accessible in other lattice-forming systems. In this work, we employ in situ high-speed atomic force microscopy to investigate the development of mixed DNA origami monolayers consisting of DNA origami triangles with threefold symmetry in the presence of rectangular DNA origami impurities with fourfold symmetry. The dynamic formation and annealing of the resulting defects is monitored in dependence of the triangle-to-rectangle ratio and correlated with the achieved lattice order. We find that the overall order of the formed DNA origami monolayer is rather resilient with regard to the presence of impurities. We even find indications that the deliberate addition of impurities at low concentrations may lead to slightly improved lattice order, presumable because they facilitate the dynamic rearrangement of neighboring lattice triangles and thus aid the annealing of non-impurity defects. Deliberate doping of DNA origami lattices with differently shaped impurities during assembly may thus provide a route toward further enhancing lattice quality via impurity-assisted annealing of lattice defects.


Assuntos
DNA/química , Nanoestruturas/química , Nanotecnologia/métodos , Adsorção , DNA/ultraestrutura , Difusão , Microscopia de Força Atômica , Nanoestruturas/ultraestrutura , Conformação de Ácido Nucleico
13.
Small ; 16(13): e1905959, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32130783

RESUMO

Although DNA origami nanostructures have found their way into numerous fields of fundamental and applied research, they often suffer from rather limited stability when subjected to environments that differ from the employed assembly conditions, that is, suspended in Mg2+ -containing buffer at moderate temperatures. Here, means for efficient cryopreservation of 2D and 3D DNA origami nanostructures and, in particular, the effect of repeated freezing and thawing cycles are investigated. It is found that, while the 2D DNA origami nanostructures maintain their structural integrity over at least 32 freeze-thaw cycles, ice crystal formation makes the DNA origami gradually more sensitive toward harsh sample treatment conditions. Whereas no freeze damage could be detected in 3D DNA origami nanostructures subjected to 32 freeze-thaw cycles, 1000 freeze-thaw cycles result in significant fragmentation. The cryoprotectants glycerol and trehalose are found to efficiently protect the DNA origami nanostructures against freeze damage at concentrations between 0.2 × 10-3 and 200 × 10-3 m and without any negative effects on DNA origami shape. This work thus provides a basis for the long-term storage of DNA origami nanostructures, which is an important prerequisite for various technological and medical applications.


Assuntos
Criopreservação , DNA , Nanoestruturas , Criopreservação/métodos , Crioprotetores/farmacologia , DNA/química , DNA/efeitos dos fármacos , Dano ao DNA , Congelamento , Glicerol/farmacologia , Nanoestruturas/química , Trealose/farmacologia
14.
Dalton Trans ; 48(44): 16812, 2019 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-31670361

RESUMO

Correction for 'Luminescent Nd2S3 thin films: a new chemical vapour deposition route towards rare-earth sulphides' by Stefan Cwik et al., Dalton Trans., 2019, 48, 2926-2938.

15.
ACS Omega ; 4(2): 2649-2660, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31459500

RESUMO

The assembly of peptides and proteins into nanoscale amyloid fibrils via formation of intermolecular ß-sheets not only plays an important role in the development of degenerative diseases but also represents a promising approach for the synthesis of functional nanomaterials. In many biological and technological settings, peptide assembly occurs in the presence of organic and inorganic interfaces with different physicochemical properties. In an attempt to dissect the relative contributions of the different molecular interactions governing amyloid assembly at interfaces, we here present a systematic study of the effects of terminal modifications on the adsorption and assembly of the human islet amyloid polypeptide fragment hIAPP(20-29) at organic self-assembled monolayers (SAMs) presenting different functional groups (cationic, anionic, polar, or hydrophobic). Using a selection of complementary in situ and ex situ analytical techniques, we find that even this well-defined and comparatively simple model system is governed by a rather complex interplay of electrostatic interactions, hydrophobic interactions, and hydrogen bonding, resulting in a plethora of observations and dependencies, some of which are rather counterintuitive. In particular, our results demonstrate that terminal modifications can have tremendous effects on peptide adsorption and assembly dynamics, as well as aggregate morphology and molecular structure. The effects exerted by the terminal modifications can furthermore be modulated in nontrivial ways by the physicochemical properties of the SAM surface. Therefore, terminal modifications are an important factor to consider when conducting and comparing peptide adsorption and aggregation studies and may represent an additional parameter for guiding the assembly of peptide-based nanomaterials.

16.
Nanoscale ; 11(35): 16270-16276, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31455950

RESUMO

DNA origami structures have developed into versatile tools in molecular sciences and nanotechnology. Currently, however, many potential applications are hindered by their poor stability, especially under denaturing conditions. Here we present and evaluate two simple approaches to enhance DNA origami stability. In the first approach, we elevated the melting temperature of nine critical staple strands by merging the oligonucleotides with adjacent sequences. In the second approach, we increased the global stability by enzymatically ligating all accessible staple strand ends directly. By monitoring the gradual urea-induced denaturation of a prototype triangular DNA origami modified by these approaches using atomic force microscopy, we show that rational redesign of a few, critical staple strands leads to a considerable increase in overall stability at high denaturant concentration and elevated temperatures. In addition, enzymatic ligation yields DNA nanostructures with superior stability at up to 37 °C and in the presence of 6 M urea without impairing their shape. This bio-orthogonal approach is readily adaptable to other DNA origami structures without the need for synthetic nucleotide modifications when structural integrity under harsh conditions is required.


Assuntos
DNA/química , Nanoestruturas/química , Conformação de Ácido Nucleico , Oligonucleotídeos/química , Ureia/química
17.
Molecules ; 24(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315177

RESUMO

DNA origami nanostructures are widely employed in various areas of fundamental and applied research. Due to the tremendous success of the DNA origami technique in the academic field, considerable efforts currently aim at the translation of this technology from a laboratory setting to real-world applications, such as nanoelectronics, drug delivery, and biosensing. While many of these real-world applications rely on an intact DNA origami shape, they often also subject the DNA origami nanostructures to rather harsh and potentially damaging environmental and processing conditions. Furthermore, in the context of DNA origami mass production, the long-term storage of DNA origami nanostructures or their pre-assembled components also becomes an issue of high relevance, especially regarding the possible negative effects on DNA origami structural integrity. Thus, we investigated the effect of staple age on the self-assembly and stability of DNA origami nanostructures using atomic force microscopy. Different harsh processing conditions were simulated by applying different sample preparation protocols. Our results show that staple solutions may be stored at -20 °C for several years without impeding DNA origami self-assembly. Depending on DNA origami shape and superstructure, however, staple age may have negative effects on DNA origami stability under harsh treatment conditions. Mass spectrometry analysis of the aged staple mixtures revealed no signs of staple fragmentation. We, therefore, attribute the increased DNA origami sensitivity toward environmental conditions to an accumulation of damaged nucleobases, which undergo weaker base-pairing interactions and thus lead to reduced duplex stability.


Assuntos
DNA/química , Nanoestruturas/química , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Microscopia de Força Atômica , Modelos Moleculares , Conformação de Ácido Nucleico
18.
Chembiochem ; 20(22): 2818-2823, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31163091

RESUMO

DNA nanostructures have emerged as intriguing tools for numerous biomedical applications. However, in many of those applications and most notably in drug delivery, their stability and function may be compromised by the biological media. A particularly important issue for medical applications is their interaction with proteins such as endonucleases, which may degrade the well-defined nanoscale shapes. Herein, fundamental insights into this interaction are provided by monitoring DNase I digestion of four structurally distinct DNA origami nanostructures (DONs) in real time and at a single-structure level by using high-speed atomic force microscopy. The effect of the solid-liquid interface on DON digestion is also assessed by comparison with experiments in bulk solution. It is shown that DON digestion is strongly dependent on its superstructure and flexibility and on the local topology of the individual structure.


Assuntos
DNA/química , Desoxirribonuclease I/química , Nanoestruturas/química , Ensaio de Desvio de Mobilidade Eletroforética , Hidrólise , Microscopia de Força Atômica/métodos , Conformação de Ácido Nucleico , Maleabilidade , Fatores de Tempo
19.
Chemistry ; 25(31): 7489-7500, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-30870572

RESUMO

New precursor chemistries for the atomic layer deposition (ALD) of aluminium oxide are reported as potential alternatives to the pyrophoric trimethylaluminium (TMA) which is to date a widely used Al precursor. Combining the high reactivity of aluminium alkyls employing the 3-(dimethylamino)propyl (DMP) ligand with thermally stable amide ligands yielded three new heteroleptic, non-pyrophoric compounds [Al(NMe2 )2 (DMP)] (2), [Al(NEt2 )2 (DMP)] (3, BDEADA) and [Al(NiPr2 )2 (DMP)] (4), which combine the properties of both ligand systems. The compounds were synthesized and thoroughly chemically characterized, showing the intramolecular stabilization of the DMP ligand as well as only reactive Al-C and Al-N bonds, which are the key factors for the thermal stability accompanied by a sufficient reactivity, both being crucial for ALD precursors. Upon rational variation of the amide alkyl chains, tunable and high evaporation rates accompanied by thermal stability were found, as revealed by thermal evaluation. In addition, a new and promising plasma enhanced (PE)ALD process using BDEADA and oxygen plasma in a wide temperature range from 60 to 220 °C is reported and compared to that of a modified variation of the TMA, namely [AlMe2 (DMP)] (DMAD). The resulting Al2 O3 layers are of high density, smooth, uniform, and of high purity. The applicability of the Al2 O3 films as effective gas barrier layers (GBLs) was successfully demonstrated, considering that coating on polyethylene terephthalate (PET) substrates yielded very good oxygen transmission rates (OTR) with an improvement factor of 86 for a 15 nm film by using DMAD and a factor of 25 for a film thickness of just 5 nm by using BDEDA compared to bare PET substrates. All these film attributes are of the same quality as those obtained for the industrial precursor TMA, rendering the new precursors safe and potential alternatives to TMA.

20.
ACS Appl Mater Interfaces ; 11(3): 3169-3180, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30624887

RESUMO

A bottom-up process from precursor development for tin to plasma-enhanced atomic layer deposition (PEALD) for tin(IV) oxide and its successful implementation in a working thin-film transistor device is reported. PEALD of tin(IV) oxide thin films at low temperatures down to 60 °C employing tetrakis-(dimethylamino)propyl tin(IV) [Sn(DMP)4] and oxygen plasma is demonstrated. The liquid precursor has been synthesized and thoroughly characterized with thermogravimetric analyses, revealing sufficient volatility and long-term thermal stability. [Sn(DMP)4] demonstrates typical saturation behavior and constant growth rates of 0.27 or 0.42 Å cycle-1 at 150 and 60 °C, respectively, in PEALD experiments. Within the ALD regime, the films are smooth, uniform, and of high purity. On the basis of these promising features, the PEALD process was optimized wherein a 6 nm thick tin oxide channel material layer deposited at 60 °C was applied in bottom-contact bottom-gate thin-film transistors, showing a remarkable on/off ratio of 107 and field-effect mobility of µFE ≈ 12 cm2 V-1 s-1 for the as-deposited thin films deposited at such low temperatures.

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