Wyniki wyszukiwania - BazTech

1

Application of Al2O3, ZnO, and TiO2 ALD thin films as antireflection coating in the silicon solar cells

Szindler Marek, Szindler Magdalena

Opto-Electronics Review

|

2023

|

Vol. 31, No. 4

art. no. e148223

EN

The article describes the results of a research on the surface morphology and optical properties of Al₂O₃, ZnO, and TiO₂ thin films deposited by atomic layer deposition (ALD) for applications in silicon solar cells. The surface topography and elemental composition were characterised using a scanning electron microscope, and thickness was determined using an optical reflectometer. The samples were structurally examined using a Raman spectrometer. The structural variant was identified: for Al₂O₃ it is sapphire, for TiO₂ it is anatase, and for ZnO it is wurtzite. Possibilities of minimising light reflection using single and double thin film systems below 5% were presented. For the first time, the effectiveness of these thin films on the current-voltage characteristics and electrical parameters of manufactured silicon solar cells was examined and compared. The solar cell with the highest efficiency of converting solar radiation into electricity was obtained for Al₂O₃/TiO₂ and the efficiency of such a photovoltaic device was 18.74%.

2

Investigations of CrN/TiO2 coatings obtained in a hybrid PVD/ALD method on Al-Si-Cu alloy substrate

Staszuk Marcin

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2023

|

Vol. 71, nr 2

art. no. e144622

EN

The paper addresses an important scientific topic from the utilitarian point of view concerning the surface treatment of Al-Si-Cu aluminum alloys by PVD/ALD hybrid coating deposition. The influence of the conditions of deposition of titanium oxide in CrN/TiO2 coatings on their structure and properties, in particular corrosion resistance, were investigated. The TiO2 layer was produced by the atomic layer deposition (ALD) method with a variable number of cycles. Structural investigations were performed using scanning and transmission electron microscopy (SEM and TEM), atomic force microscopy (AFM), and Raman spectroscopy methods. Electrochemical properties were analyzed using potentiodynamic and electrochemical impedance spectroscopy (EIS) methods. The CrN/TiO2 hybrid coating with titanium oxide deposited at 500 ALD cycles showed the best corrosion properties. It was also found that the prerequisite for obtaining the best electrochemical properties was the amorphous structure of titanium oxide in the tested hybrid coatings. The high tribological properties of the tested coatings were also confirmed.

3

Structural, Electrical, and Optical Properties of ZnO Films Grown by Atomic Layer Deposition at Low Temperature

Park Ji-Young, Weon Ye Bin, Jung Myeong Jun, Choi Byung Joon

Archives of Metallurgy and Materials

|

2022

|

Vol. 67, iss. 4

1503--1506

EN

Zinc oxide (ZnO) is a prominent n-type semiconductor material used in optoelectronic devices owing to the wide bandgap and transparency. The low-temperature growth of ZnO thin films expands diverse applications, such as growth on glass and organic materials, and it is also cost effective. However, the optical and electrical properties of ZnO films grown at low temperatures may be inferior owing to their low crystallinity and impurities. In this study, ZnO thin films were prepared by atomic layer deposition on SiO2 and glass substrates in the temperature range of 46-141℃. All films had a hexagonal würtzite structure. The carrier concentration and electrical conductivity were also investigated. The low-temperature grown films showed similar carrier concentration (a few 1019 cm-3 at 141°C), but possessed lower electrical conductivity compared to high-temperature (>200°C) grown films. The optical transmittance of 20 nm thin ZnO film reached approximately 90% under visible light irradiation. Additionally, bandgap energies in the range of 3.23-3.28 eV were determined from the Tauc plot. Overall, the optical properties were comparable to those of ZnO films grown at high temperature.

4

Modern methods of surface modification for new-generation titanium alloys

Lisoń-Kubica Julia, Taratuta Anna, Goldsztajn Karolina, Antonowicz Magdalena, Walke Witold, Dyner Aneta, Basiaga Marcin

Acta of Bioengineering and Biomechanics

|

2022

|

Vol. 24, no. 4

147--158

EN

The constantly growing need for the use of implants in osteotomy is mainly due to the aging population and the need for long-term use of this type of biomaterials. Improving implant materials requires the selection of appropriate functional properties. Currently used titanium (Ti) alloys, such as Ti6Al4V and Ti6Al7Nb, are being replaced by materials with better biocompatibility, such as vanadium(V) or niobium (Nb), allowing for creation of the so-called new generation alloys. These new alloys, with the incorporation of zirconium (Zr), iron, and tantalum, possess Young’s modulus close to that of a bone, which further improves the improves the biomaterial’s. biocompatibility. This article describes the atomic layer deposition (ALD) method and its possible applications in the new generation of titanium alloys for biomedical applications. Also, the exemplary results of tin oxide (SnO2) thin coatings deposited by ALD and physical vapor deposition (PVD) methods are presented. This study aimed to evaluate the physicochemical properties of a Ti13Nb13Zr alloy used for elements in the skeletal system. As the temperature and the number of cycles vary, the results demonstrate that the surface area of the samples changes. The uncoated Ti13Nb13Zr alloy exhibits hydrophilic properties. However, all coated specimens improve in this respect and provide improved clinical results. after the applied modification, the samples have a smaller contact angle, but still remain in the range of 0–90°, which makes it possible to conclude that their nature remains hydrophilic. Coating the specimens decreased the mineralization risk of postoperative complications. As a result, the biomaterials demonstrated improved effectiveness, decreased complication indicators, and improved patient well-being.

5

Growth Temperature Effect of Atomic-Layer-Deposited GdOx Films

Ryu Sung Yeon, Yun Hee Ju, Lee Min Hwan, Choi Byung Joon

Archives of Metallurgy and Materials

|

2021

|

Vol. 66, iss. 3

755--758

EN

Gadolinium oxide (Gd2O3) is one of the lanthanide rare-earth oxides, which has been extensively studied due to its versatile functionalities, such as a high permittivity, reactivity with moisture, and ionic conductivity, etc. In this work, GdOx thin film was grown by atomic layer deposition using cyclopentadienyl (Cp)-based Gd precursor and water. As-grown GdOx film was amorphous and had a sub-stoichiometric (x ~ 1.2) composition with a uniform elemental depth profile. ~3 nm-thick GdOx thin film could modify the hydrophilic Si substrate into hydrophobic surface with water wetting angle of 70°. Wetting and electrical test revealed that the growth temperature affects the hydrophobicity and electrical strength of the as-grown GdOx film.

6

The optical parameters of TiO2 antireflection coating prepared by atomic layer deposition method for photovoltaic application

Szindler Marek, Szindler Magdalena M.

Optica Applicata

|

2020

|

Vol. 50, nr 4

663--670

EN

Titanium dioxide thin films have been deposited on silicon wafers substrates by an atomic layer deposition (ALD) method. There optical parameters were investigated by spectroscopic ellipsometry and UV/VIS spectroscopy. A material with a refractive index of 2.41 was obtained. Additionally, in a wide spectral range it was possible to reduce the reflection from the silicon surface below 5%. The Raman spectroscopy method was used for structural characterization of anatase TiO2 thin films. Their uniformity and chemical composition are confirmed by a scanning electron microscope (SEM) energy dispersive spectrometer (EDS).

7

Electrical Characteristics of Tin Oxide Films Grown by Thermal Atomic Layer Deposition

Yoon Seong Yu, Choi Byung Joon

Archives of Metallurgy and Materials

|

2020

|

Vol. 65, iss. 3

1041--1044

EN

Tin dioxide (SnO2 ) is an n-type semiconductor and has useful characteristics of high transmittance, excellent electrical properties, and chemical stability. Accordingly, it is widely used in a variety of fields, such as a gas sensor, photocatalyst, optoelectronics, and solar cell. In this study, SnO2 films are deposited by thermal atomic layer deposition (ALD) at 180°C using Tetrakis(dimethylamino)tin and water. A couple of 5.9, 7.4 and 10.1nm-thick SnO2 films are grown on SiO2 /Si substrate and then each film is annealed at 400°C in oxygen atmosphere. Current transport of SnO2 films are analyzed by measuring current – voltage characteristics from room temperature to 150°C. It is concluded that electrical property of SnO2 film is concurrently affected by its semiconducting nature and oxidative adsorption on the surface.

8

Metody badawcze cienkich warstw wytworzonych metodą osadzania warstw atomowych

Boryło Paulina, Szindler Marek, Szindler Magdalena, Lukaszkowicz Krzysztof

LAB Laboratoria, Aparatura, Badania

|

2019

|

R. 24, nr 5

16--18

9

Nanometryczne warstwy tlenku cynku wytwarzane metodami próżniowymi

Boryło Paulina, Lukaszkowicz Krzysztof

Elektronika : konstrukcje, technologie, zastosowania

|

2019

|

Vol. 60, nr 9

6--10

PL

Celem artykułu jest porównanie wpływu metody wytwarzania oraz temperatury procesu na własności cienkich warstw tlenku cynku. Zbadano strukturę, morfologię i topografię wytworzonych warstw oraz ich własności optyczne i elektryczne. Badane warstwy ZnO zostały wytworzone w procesie rozpylania magnetronowego oraz osadzania warstw atomowych. Przeprowadzone badania wykazały wpływ metody wytwarzania oraz temperatury procesu na analizowane własności.

EN

The aim of this article is to compare the influence of prepation methods and process temperature on the production effects and properties of zinc oxide thin films. Coducted experiments included investigations of structure, morphology and topography of deposited thin films as well as their optical and electrical properties. Tested ZnO thin films were prepared by magnetron sputtering and atomic layer deposition metods. Results of studies have shown that impact of the manufacturing method and process temperature on the analyzed properties is significant.

10

Struktura i własności warstw Al₂O₃ osadzonych metodą ALD na krzemowych ogniwach fotowoltaicznych

Szindler M., Szindler M.

Elektronika : konstrukcje, technologie, zastosowania

|

2018

|

Vol. 59, nr 9

9--11

PL

W pracy zbadano możliwości zminimalizowania współczynnika odbicia światła, a w konsekwencji zwiększenia sprawności wytwarzanych krzemowych ogniw fotowoltaicznych, poprzez wytworzenie cienkiej warstwy antyrefleksyjnej Al₂O₃ metodą atomowego osadzania warstw. Badania morfologii powierzchni warstw wykonano przy użyciu skaningowego mikroskopu elektronowego, z kolei strukturę zbadano przy użyciu dyfraktometru rentgenowskiego. W celu okreslenia własności optycznych cienkich warstw Al₂O₃ wykonano badania współczynnika odbicia światła przy użyciu spektrofotometru. Ogniwo fotowoltaiczne z osadzoną w temperaturze 300°C metodą ALD warstwą antyrefleksyjną przy zadanej liczbie cykli 830 osiągnęło sprawność 12,51%, podczas gdy sprawność ogniwa referencyjnego bez warstwy antyrefleksyjnej wyniosła 7,22%.

EN

The main goal of the study was to examine the possibility of minimizing the reflectance of light, and consequently increasing the efficiency of the produced silicon solar cells, by creating an Al₂O₃ antireflection coating by atomic layer deposition method (ALD). Surface layer morphology studies were performed by using scanning electron microscopy, while the structure was examined by using an X-ray diffractometer. In order to determine the optical properties of the Al₂O₃ thin films, light reflectance measurements were performed using a spectrophotometer. The solar cell with deposited antireflection coating by the ALD method with a 830 number of cycles at 300°C reached the efficiency of 12.51%, while the efficiency of the reference cell is 7.22%.

11

Temperature Effect on the Growth Rate and Physical Characteristics of SnO2 Thin Films Grown by Atomic Layer Deposition

Kim D., Kim D. H., Riu D.-H., Choi B. J.

Archives of Metallurgy and Materials

|

2018

|

Vol. 63, iss. 2

1061--1064

EN

Among the various thin film coating techniques, atomic layer deposition (ALD) has features of good controllability of the thickness, excellent step-coverage in 3-dimensional object even in the sub-nm thickness range at the relatively low deposition temperature. In this study, SnO2 thin films were grown by ALD in the variation of substrate temperatures from 150 to 250°C. Even such a low temperature may influence on the growth kinetics of the ALD reaction and thus the physical characteristics of thin films, such as crystallinity, film density and optical band gap, etc. We observed the decrease of the growth rate with increasing substrate temperature, at the same time, the density of the film was decreased with increasing temperature. Steric hindrance effect of the precursor molecule was attributed to the inverse relationship of the growth temperature and growth rate as well as the film density. Optical indirect band gap energy (~3.6 eV) of the ALD-grown amorphous SnO2 films grown at 150°C was similar with that of the literature value, while slightly lower band gap energy (~3.4 eV) was acquired at the films grown at higher temperature.

12

The new generation of the biologicalengineering materials for applications in medical and dental implant-scaffolds

Dobrzański L. A., Dobrzańska-Danikiewicz A. D., Czuba Z. P., Dobrzański L. B., Achtelik-Franczak A., Malara P., Szindler M., Kroll L.

Archives of Materials Science and Engineering

|

2018

|

Vol. 91, nr 2

56--85

EN

Purpose: The publication aims to find the relationship between the proliferation of surface layers of living cells and the deposition of thin atomic layers deposition ALD coatings on the pores internal surfaces of porous skeletons of medical and dental implant-scaffolds manufactured with the selective laser deposition SLS additive technology using titanium and Ti6Al4V alloy. Design/methodology/approach: The extensive review of the literature presents the state-of-the-art in the field of regenerative medicine and tissue engineering. General ageing of societies, increasing the incidence of oncological diseases and some transport and sports accidents, and also the spread of tooth decay and tooth cavities in many regions of the world has taken place nowadays. Those reasons involve resection of many tissues and organs and the need to replace cavities, among others bones and teeth through implantation, more and more often hybridized with tissue engineering methods. Findings: The results of investigations of the structure and properties of skeleton microporous materials produced from titanium and Ti6Al4V alloy powders by the method of selective laser sintering have been presented. Particularly valuable are the original and previously unpublished results of structural research using high-resolution transmission electron microscope HRTEM. Particular attention has been paid to the issues of surface engineering, in particular, the application of flat TiO2 and Al2O3 coatings applied inside micropores using the atomic layers deposition ALD method and hydroxyapatite applied the dip-coating sol-gel method, including advanced HRTEM research. The most important part of the work concerns the research of nesting and proliferation of live cells of osteoblasts the hFOB 1.19 (Human ATCC - CRL - 11372) culture line on the surface of micropores with surfaces covered with the mentioned layers. Research limitations/implications: The investigations reported in the paper fully confirmed the idea of the hybrid technology of producing microporous implants and implant-scaffolds to achieve original Authors’ biological-engineering materials. The surface engineering issues, including both flat-layered nonorganic coatings and interactions of those coverings with flat layers of living cells, play a crucial role. Originality/value: Materials commonly used in implantology and the most commonly used materials processing technologies in those applications have been described. Against that background, the original Authors' concept of implant-scaffolds and the application of microporous skeleton materials for this purpose have been presented.

13

Metallic skeletons as reinforcement of new composite materials applied in orthopaedics and dentistry

Dobrzański L. A., Dobrzańska-Danikiewicz A. D., Czuba Z. P., Dobrzański L. B., Achtelik-Franczak A., Malara P., Szindler M., Kroll L.

Archives of Materials Science and Engineering

|

2018

|

Vol. 92, nr 2

53--85

EN

Purpose: The article concerns the development of completely new groups of composite materials that can be used to produce functional replacements for damaged bones or teeth. Design/methodology/approach: A selective laser sintering was used to produce the reinforcement of those materials from titanium and its Ti6Al4V alloy in the form of skeletons with pores with adjustable geometric features. The matrix of those materials is either air or crystallised from the liquid AlSi12 or AlSi7Mg0.3 alloys condition after prior vacuum infiltration or human osteoblast cells from the hFOB 1.19 (Human ATCC - CRL - 11372) culture line. Findings: The porous material may be used for the non-biodegradable scaffold. After implantation into the body in the form of an implant-scaffold one, it allows the natural cells of the patient to grow into the pores of the implant, and it fuses with the bone or the appropriate tissue over time. The essential part of the implant-scaffold is the porous part inseparably connected with the core of solid materials. Into pores can grow living cells. Research limitations/implications: Biological-engineering composite materials in which natural cells were cultured in the pores in the laboratory next are combined as an artificial material with the natural cells of the patient in his/her body. Practical implications: The hybrid technologies of the all group of those materials were obtained and optimised. Numerous structure research was carried out using the most modern research methods of contemporary materials engineering, and mechanical tests and biological research involving the cultivation of natural cells were realised. Originality/value: The results of the research indicate the accuracy of the idea of implementing a new group of biological-engineering materials and the wide possibilities of their application in regenerative medicine.

14

Comparison of surface morphology and structure of Al2O3 thin films deposited by sol-gel and ALD methods

Szindler M., Szindler M. M., Pawlyta M., Jung T., Dobrzański L. A.

Journal of Achievements in Materials and Manufacturing Engineering

|

2017

|

Vol. 82, nr 2

49--57

EN

Purpose: of this research was examination Al2O3 thin film obtained with two different method, by sol-gel and ALD, and comparison the surface morphology and structure of deposited thin films. The films deposited on the monocrystalline silicon were tested for their suitability for use in silicon solar cells. Design/methodology/approach: Trimethylaluminum (TMA) was used as a precursor of Al2O3 which is reacted with water enabled the deposition of thin films by ALD method. By the sol-gel method the aluminium tri-sec butoxide (TBA) was used as a precursor to obtain Al2O3 thin films. The aluminium oxide solutions prepared by sol-gel method were deposited by spin coating technique. Examination of the structure and morphology of the surface of the Al2O3 thin films deposited by sol gel and ALD method were performed using atomic force microscope and transmission electron microscope. For the analysis of surface topography deposited thin films atomic force microscope XE-100 from Park Systems was used. Qualitative analysis of the chemical composition was carried out using an energy dispersion spectrometer (EDS). The detailed structural studies were conducted using a Titan 80-300 scanning-transmission electron microscope S/TEM from the FEI Company. Detailed research on the structure of the deposited Al2O3 thin films were performed. The HRTEM images and diffraction SAED were recorded. Findings: The small atoms clusters of a width less than 20 nm were documented. The thin film deposited by spin-coating technique on silicon substrate with 3000 rpm is characterized by RMS and Ra values of, respectively, 0.26 and 0.2 nm. RMS was defined as rough mean square parameter and Ra was defined as the arithmetic mean deviation of the profile from the mean line. An analysis of the frequency histograms of irregularities of the thin film obtained by the spin coating on a silicon substrate at 3000 rpm shows that a large part of them does not exceed 0.5 nm, and the single irregularities reach up to 2.2 nm. When comparing the AFM pictures with the thin films deposited by ALD technique and spin-coating it has been found that the thin films obtained on polished silicon substrates are similar in morphology. The EDS spectra shows the characteristic for oxygen (0.525 keV) and aluminum (1.486 keV) reflections derived from the thin film. In Al2O3 thin film obtained by ALD method the occurrence of α phase of aluminum oxide with a hexagonal structure was identified, just like in the case of thin film deposited by sol-gel. Practical implications: Known aluminium oxide properties and the possibility of obtaining a uniform thin layer show that it can be good material for different application. Precise description of the properties of Al2O3 is very important, since this material is one of the most frequently used in catalyst industry, in medicine, electronics and photovoltaics, as well as a protective layer. The Al2O3 thin film can act as passive and anti-reflective layer simultaneously in silicon solar cell. Using this thin film can simplify the technology of manufacturing silicon solar cells Originality/value: The paper presents researches of aluminium oxide thin films deposited by sol-gel and atomic layer deposition method on monocrystalline silicon.

15

The impact of atomic layer deposition technological parameters on optical properties and morphology of Al2O3 thin films

Dobrzanski L. A., Szindler M., Szindler M., Hajduk B., Kotowicz S.

Optica Applicata

|

2015

|

Vol. 45, nr 4

573--583

EN

This paper presents some results of investigations on aluminum oxide Al2O3 thin films prepared by the atomic layer deposition method on polished monocrystalline silicon. It has been described how the technological parameters of the deposition process, like the number of cycles and substrate temperature, influenced the optical properties and morphology of prepared thin films. Their physical and optical properties like thickness, uniformity and refractive index have been investigated with spectroscopic ellipsometry, atomic force microscopy and UV/vis optical spectroscopy.

16

Characteristics of ZnO thin films deposited by atomic layer deposition

Boryło P., Lukaszkowicz K., Szindler M., Basiaga M.

Journal of Achievements in Materials and Manufacturing Engineering

|

2015

|

Vol. 73, nr 2

86--91

EN

Purpose:The aim of this article was to examine the adhesion of ZnO thin films and the influence of temperature deposition process on their morphology. ZnO thin films have been deposited by atomic layer deposition. Design/methodology/approach: Adhesion of ZnO thin films was investigated using the scratch test method. Changes in the surface morphology were observed by scanning electron microscope (SEM). In order to confirm the chemical composition and phase investigated of thin films was carried out Energy-dispersive X-ray spectroscopy EDS and X-ray analysis. Findings: Results and their analysis have shown that the ZnO thin films deposited by ALD are uniform and homogenous. Significant impact on their morphology has the temperature of the deposition process. In the case of the adhesion temperature is negligible. Practical implications: Knowledge about the ALD ZnO thin films are possibility to obtaining a uniform thin films show that material has a big potential in optoelectronics and photovoltaic application. Originality/value: The article presents the original research results of the structure and properties of ZnO thin films deposited by ALD method, that can replace a commonly used transparent conductive layer.

17

Atomic layer deposition of TiO2 onto porous biomaterials

Dobrzański L. A., Dobrzańska-Danikiewicz A. D., Szindler M., Achtelik-Franczak A., Pakieła W.

Archives of Materials Science and Engineering

|

2015

|

Vol. 75, nr 1

5--11

EN

Purpose: The aim of this article was to investigate the possibility of uniform coverage of porous biomaterials with a thin film of titanium oxide deposited using the atomic layer deposition method (ALD) Design/methodology/approach: The porous biomaterials were prepared by Selective Laser Melting (SLM) from Ti powder. The TiO2 thin films were prepared with use of atomic layer deposition method. The changes in surface topography was observed by the atomic force microscope AFM XE-100 and scanning electron microscope SEM. The measurement of thickness performed using spectroscopic ellipsometer. Findings: Results and their analysis have confirmed show that the atomic layer deposition (ALD) method allows the deposition of homogenous and uniform thin films of TiO2 with the desired geometric characteristics onto porous Ti biomaterials. Practical implications: The combination of porous substrate made from titanium which has good mechanical properties with a biocompatible titanium oxide provides practical possibilities of use for example in dental engineering. Originality/value: The combination of porous substrate made from titanium which has good mechanical properties with a biocompatible titanium oxide provides practical possibilities of use for example in dental engineering.

18

Opracowanie efektywnych metod domieszkowania warstw ZnO glinem w procesie ALD i optymalizacja tych warstw

Pietruszka R., Luka G, Witkowski B. S., Wachnicki Ł., Gieraltowska S, Stapiński T., Marszałek K., Godlewski M.

Przegląd Elektrotechniczny

|

2014

|

R. 90, nr 10

203-205

PL

Warstwy tlenku cynku domieszkowanego atomami glinu ZnO:Al były wzrastane metodą osadzania warstw atomowych (ALD, z ang. A-atomic, L-layer, D-deposition). Na szklanych podłożach osadzono warstwy ZnO:Al (tzw. warstwa AZO) o grubości 200 nm. Temperatura osadzania warstwy AZO była równa 160 oC. Najlepsze parametry elektryczne oraz krystalograficzne otrzymano używając dwóch wysoko reaktywnych prekursorów cynku i glinu. Użyto diethylzinc jako prekursor cynkowy oraz trimethylaluminum jako prekursor glinowy. Otrzymane struktury wykazały wysoką transmisję oraz niskie rezystywności rzędu 10-3 Ωcm. Po optymalizacji procesu wzrostu warstw ZnO:Al testowano je jako przezroczyste elektrody do zastosowań fotowoltaicznych.

EN

We achieved high conductivity of zinc oxide layers doped with aluminum atoms using atomic layer deposition (ALD) method. Their growth mode, electrical and optical properties have been investigated. We discuss how the growth temperature and doping affect resistivity and optical properties of the films. The obtained resistivities of ZnO:Al thin films ( 1.2x10-3 Ωcm) and high transparency make them suitable for the TCO applications in photovoltaics.

19

Properties of thin films of high-k oxides grown by atomic layer deposition at low temperature for electronic applications

Gieraltowska S., Wachnicki Ł., Witkowski B. S., Godlewski M., Guziewicz E.

Optica Applicata

|

2013

|

Vol. 43, nr 1

17--25

EN

Thin films of high-k oxides are presently used in semiconductor industry as gate dielectrics. In this work, we present the comparison of structural, morphological and electrical properties of binary and composite layers of high-k oxides that include hafnium dioxide (HfO2), aluminum oxide (Al2O3) and zirconium dioxide (ZrO2). We deposit thin films of high-k oxides using atomic layer deposition (ALD) and low growth temperature (60–240 °C). Optimal technological growth parameters were selected for the maximum smoothness, amorphous microstructure, low leakage current, high dielectric strength of dielectric thin films, required for gate applications. High quality of the layers is confirmed by their introduction to test electronic structures, such as thin film capacitors, transparent thin film capacitors and transparent thin film transistors. In the latter structure we use semiconductor layers of zinc oxide (ZnO) and insulating layers of high-k oxide grown by the ALD technique at low temperature (no more than 100 °C).

20

Al2O3 antireflection coatings for silicon solar cells

Dobrzański L.A., Szindler M.

Journal of Achievements in Materials and Manufacturing Engineering

|

2013

|

Vol. 59, nr 1

13--19

EN

Purpose: The aim of this paper was to investigate changes in surface morphology and optical properties of thin films of Al2O3. Thin films were prepared using atomic layer deposition (ALD) method. Design/methodology/approach: The microanalysis was investigated by the Energy-dispersive X-ray spectroscopy EDS. The changes in surface topography was observed by the atomic force microscope AFM XE-100 and scanning electron microscope SEM. The results of roughness was obtained by the software XEI Park Systems. The measurement of thickness and dispersion of refractive index was performed using SE800 PV spectroscopic ellipsometer. The optical reflection was investigated by the spectrometer UV/VIS. Findings: Results and their analysis allow to conclude that the atomic layer deposition method enables uniform coating of smooth and complicated shapes surfaces. The thin film thickness depends only on the number of cycles, so that can be easily control the thickness of the material. Practical implications: Knowledge about the ALD Al2O3 optical parameters and the possibility to obtaining a uniform thin films show that the previously named material has a big potential in photovoltaic application. Originality/value: The paper presents some researches of aluminium trioxide thin films deposited by atomic layer deposition method on monocrystalline silicon.