Electrical and Physical Properties of (K0.5Na0.5)NbO3 Ferroelectric Thin Films

Lead-free potassium sodium niobate ceramic thin films were synthesized using rf magnetron sputtering technology for MFIS structures. The optimal sputtering parameters of the as-deposited KNN thin films for depositing times of 1h were obtained. Regarding the measured physical properties, the micro-structure and thickness of as-deposited KNN thin films for different oxygen concentration were obtained and compared by XRD patterns and SEM images. The surface roughness of KNN thin film was also observed by AFM morphology. The average grain size and root mean square roughness were 250 and 7.04 nm, respectively. For KNN thin films in the MFIS structure, the capacitance and leakage current density were 280 pF and 10-8A/cm2, respectively. We investigated that the leakage current density and the memory window increased, the capacitance critically increased as the oxygen concentration increased from 0 to 40%. However, the excess oxygen concentration process was decreased the electrical and physical of as-deposited KNN thin film. The effect of oxygen concentration on the physical and electrical characteristics of KNN thin films was investigated and determined.

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Electrical and Physical Properties of Sodium Potassium Niobates Thin Films Prepared by rf Magnetron Sputtering Technology

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.532 ◽

2011 ◽

Vol 239-242 ◽

pp. 532-535

Author(s):

Chien Min Cheng ◽

Shih Fang Chen ◽

Jen Hwan Tsai ◽

Kai Huang Chen ◽

Hsiu Hsien Su

Keyword(s):

Thin Film ◽

Thin Films ◽

Magnetron Sputtering ◽

Physical Properties ◽

Leakage Current ◽

Oxygen Concentration ◽

Leakage Current Density ◽

Current Density ◽

Rf Magnetron Sputtering ◽

Average Grain Size

Lead-free potassium sodium niobate ceramic thin films were synthesized using rf magnetron sputtering technology for MFIS structures. The optimal sputtering parameters of the as-deposited KNN thin films for depositing times of 1h were obtained. Regarding the measured physical properties, the micro-structure and thickness of as-deposited KNN thin films for different oxygen concentration were obtained and compared by XRD patterns and SEM images. The surface roughness of KNN thin film was also observed by AFM morphology. The average grain size and root mean square roughness were 250 and 7.04 nm, respectively. For KNN thin films in the MFIS structure, the capacitance and leakage current density were 280 pF and 10-8A/cm2, respectively. We investigated that the leakage current density and the memory window increased, the capacitance critically increased as the oxygen concentration increased from 0 to 40%. However, the excess oxygen concentration process was decreased the electrical and physical of as-deposited KNN thin film. The effect of oxygen concentration on the physical and electrical characteristics of KNN thin films was investigated and determined.

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Influence of Ta2O5, TiO2, and ZrO2 Interfacial Layers on Structural and Electrical Properties of Laser Ablated Ba0.5Sr0.5TiO3 Thin Films

MRS Proceedings ◽

10.1557/proc-748-u6.5 ◽

2002 ◽

Vol 748 ◽

Author(s):

Suprem R. Das ◽

Rasmi R. Das ◽

P. Bhattacharya ◽

Ram S. Katiyar

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Leakage Current ◽

Leakage Current Density ◽

Current Density ◽

Buffer Layers ◽

Bst Thin Films ◽

Interfacial Layers ◽

Average Grain Size ◽

Structural And Electrical Properties

ABSTRACTPulsed laser deposition technique was used to fabricate Ba0.5Sr0.5TiO 3 (BST) thin-films on Pt/TiO 2/SiO2/Si substrates. The influence of thin interfacial layers of Ta2O5, TiO2, and ZrO2, on the structural and electrical properties of BST thin films was investigated. Insertion of interfacial layers does not affect the perovskite phase formation of BST thin films. Buffer layers helped to make uniform distribution of grains and resulted in a relative increase in the average grain size. The dielectric tunability of BST thin films was reduced with the presence of buffer layers. A BST thin film having a dielectric permitivity of 470 reduced to 337, 235 and 233 in the presence of Ta2O5, TiO2, and ZrO2 layers, respectively. The reduction of the relative dielectric permittivity of BST films with the insertion of interfacial layers was explained in terms of a series capacitance effect, due to the low dielectric constant of interfacial layers. The TiO2 layer did not show any appreciable change in the leakage current density. Deposition of thin Ta2O5 and ZrO2 interfacial layer on top of Pt reduced the leakage current density by an order of magnitude.

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Effects of Lattice and Thermal Mismatch Induced by Different Seed Layers on (Na0.8K0.2)0.5Bi0.5TiO3 Ferroelectric Thin Film

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.291-294.2636 ◽

2013 ◽

Vol 291-294 ◽

pp. 2636-2640 ◽

Cited By ~ 1

Author(s):

Yue Qiu Gong ◽

Ren Jie Huang ◽

Xu Jun Li ◽

Xue Jun Zheng

Keyword(s):

Thin Film ◽

Thin Films ◽

Leakage Current ◽

Leakage Current Density ◽

Current Density ◽

Perovskite Phase ◽

Ferroelectric Thin Film ◽

Micro Electro Mechanical System ◽

Thermal Mismatch ◽

Seed Layers

(Na0.8K0.2)0.5Bi0.5TiO3 (NKBT20) lead free environmental protection thin films were deposited on Si(100), Pt/Ti/SiO2/Si(100), LaNiO3/SiO2/Si(100) and SrTiO3(STO)/Pt/Ti/SiO2/Si(100) by metal organic decomposition, and the effects of mismatch induced by different seed layers on microstructures, leakage current density, ferroelectric and dielectric properties of these thin films were investigated in detail. The NKBT20/STO thin film with single perovskite phase is of the largest grain size, dielectric constant, remnant polarization and the smallest leakage current density. This could be attributed to the fact that the optimum seed layers can lower the lattice and thermal mismatch between the seed layers and the thin film. The improved electric properties may make NKBT20/STO thin film a promising candidate in micro-electro-mechanical system.

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The Electrical and Physical Properties of (Ba0.7Sr0.3)(Ti0.9Zr0.1)O3 Thin Films under Conventional Annealing Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.434-435.271 ◽

2010 ◽

Vol 434-435 ◽

pp. 271-274

Author(s):

Kai Huang Chen ◽

Cheng Fu Yang ◽

Chien Chen Diao

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Physical Properties ◽

Leakage Current ◽

Leakage Current Density ◽

Current Density ◽

X Ray Diffraction ◽

Maximum Dielectric Constant ◽

Xrd Patterns ◽

Conventional Annealing

In this study, conventional furnace annealing (CFA) is used as the post-treated process, the effects of annealing temperatures on the crystallization and microstructure of (Ba0.7Sr0.3)(Ti0.9 Zr0.1)O3 (BSTZ) thin films will be developed, and the further influences on the electrical properties of BSTZ thin films are also investigated. A previous study made in our laboratory had shown that the dielectric constant and leakage current density of BSTZ thin film with 640 nm thickness are 192 and 10-6 A/cm2 under the frequency of 100 KHz, respectively. However, the maximum dielectric constant and minimum leakage current density of BSTZ thin films under CFA process are 420 (annealed at 800oC) and 10-8 A/cm2 (700oC), respectively. Besides, the X-ray diffraction (XRD) patterns and the SEM morphology show that crystalline features and grain size of BSTZ thin films increase with the increase of CFA-treated temperatures. These experiment results suggest that a strong correlation exhibits that the physical properties will influence the dielectric properties and nucleation features of BSTZ thin films.

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Application of Amorphous Zirconium-Yttrium-Aluminum-Magnesium-Oxide Thin Film with a High Relative Dielectric Constant Prepared by Spin-Coating

Membranes ◽

10.3390/membranes11080608 ◽

2021 ◽

Vol 11 (8) ◽

pp. 608

Author(s):

Huiyun Yang ◽

Zhihao Liang ◽

Xiao Fu ◽

Zhuohui Xu ◽

Honglong Ning ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Dielectric Constant ◽

Magnesium Oxide ◽

Leakage Current ◽

Leakage Current Density ◽

Current Density ◽

Relative Dielectric Constant ◽

Oxide Thin Film ◽

Yttrium Aluminum

Amorphous metal oxide has been a popular choice for thin film material in recent years due to its high uniformity. The dielectric layer is one of the core materials of the thin film transistor (TFT), and it affects the ability of charges storage in TFT. There is a conflict between a high relative dielectric constant and a wide band gap, so we solved this problem by using multiple metals to increase the entropy of the system. In this paper, we prepared zirconium-yttrium-aluminum-magnesium-oxide (ZYAMO) dielectric layers with a high relative dielectric constant using the solution method. The basic properties of ZYAMO films were measured by an atomic force microscope (AFM), an ultraviolet-visible spectrophotometer (UV-VIS), etc. It was observed that ZYAMO thin films had a larger optical band when the annealing temperature increased. Then, metal-insulator-metal (MIM) devices were fabricated to measure the electrical properties. We found that the leakage current density of the device is relatively lower and the ZYAMO thin film had a higher relative dielectric constant as the concentration went up. Finally, it reached a high relative dielectric constant of 56.09, while the leakage current density was no higher than 1.63 × 10−6 A/cm2@ 0.5 MV/cm at 1.0 M and 400 °C. Therefore, the amorphous ZYAMO thin films has a great application in the field of high permittivity request devices in the future.

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Surface and interface properties of ferroelectric BaTiO3 thin films on Si using RuO2 as an electrode

Journal of Materials Research ◽

10.1557/jmr.1994.2561 ◽

1994 ◽

Vol 9 (10) ◽

pp. 2561-2565 ◽

Cited By ~ 36

Author(s):

Q.X. Jia ◽

L.H. Chang ◽

W.A. Anderson

Keyword(s):

Thin Film ◽

Thin Films ◽

Dielectric Constant ◽

Leakage Current ◽

Leakage Current Density ◽

Current Density ◽

Bottom Electrode ◽

Rf Magnetron Sputtering ◽

Interface Properties ◽

Surface And Interface

Ferroelectric BaTiO3 thin films were deposited on Si by rf magnetron sputtering. A conductive oxide, RuO2, was used as the bottom electrode of the capacitors. The performance of the thin film capacitors was found to be a strong function of the surface and interface properties between ferroelectric BaTiO3 and the bottom electrode. A suitable capacitor configuration must be used to preserve the bottom electrode, to enhance the dielectric constant, and to reduce the leakage current density of the films. BaTiO3 thin film on the RuO2/Si substrate, where the BaTiO3 thin film has a bilayer structure of polycrystalline on microcrystalline, showed a dielectric constant of 125 at a frequency of 1 MHz, leakage current density of 10−6 A/cm2 at a field intensity of 2.5 × 105 V/cm, and a breakdown voltage above 106 V/cm.

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Growth of Epitaxial Site-Engineered Bi4Ti3O12-Basded Thin Films by Mocvdand Their Characterization

MRS Proceedings ◽

10.1557/proc-748-u2.2 ◽

2002 ◽

Vol 748 ◽

Author(s):

Hiroshi Funakubo ◽

Tomohiro Sakai ◽

Takayuki Watanabe ◽

Minoru Osada ◽

Masato Kakihana ◽

...

Keyword(s):

Thin Films ◽

Leakage Current ◽

Leakage Current Density ◽

Current Density ◽

Spontaneous Polarization ◽

Chemical Vapor ◽

The Other ◽

Other Hand ◽

La Substitution ◽

Lower Temperature

ABSTRACTThin films of BIT, La-substituted BIT (BLT) and La- and V-cosubstituted BIT(BLTV) were epitaxially grown on SrRuO3//SrTiO3 substrates at 850°C by metalorganic chemical vapor deposition (MOCVD), and their electrical properties were systematically compared. All films on (100), (110) and (111)-oriented substrates were epitaxially grown with (001)-, (104)-/(014)-and (118) –preferred orientations, respectively. The leakage current density of the BLTV film was almost the same with that of the BLT film, but was smaller than that of BIT film, suggesting that the La substitution contributed to the decrease of the leakage current density especially in pseudoperovskite layer. Spontaneous polarization of the BLTV film was estimated to be almost the same with the BLT film but was smaller that that of the BIT film. This is explained by the decrease of Tc with the La substitution, while V did not contribute to the change of the Curie temperature (Tc ). On the other hand, the coercive field (Ec) value of the BLTV was smaller than that of the BIT and the BLT films. As a result, La substitution contributed to the decrease of the leakage current density together with the decrease of the spontaneous polarization due to the decrease of the Tc. On the other hand, V substitution contributes to the decrease of the defects that suppress the domain motion and increases the Ec value. Therefore, each substitution of La and V plays different roles and this contribution is remarkable for the films deposited at lower temperature.

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Preparation and Characterization Of SrTio3 Thin Films Using ECR Plasma Assisted MOCVD

MRS Proceedings ◽

10.1557/proc-415-183 ◽

1995 ◽

Vol 415 ◽

Author(s):

Joon Sung Lee ◽

Han Wook Song ◽

Dae Sung Yoon ◽

Byung Hyuk Jun ◽

Byoung Gon Yu ◽

...

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Leakage Current ◽

Leakage Current Density ◽

Current Density ◽

Oxygen Plasma ◽

Grain Structure ◽

Breakdown Field ◽

Ecr Plasma ◽

Step Coverage

ABSTRACTSrTiO3 thin films were prepared on Si(p-type 100) and Pt/SiO2/Si substrates using ECR plasma (or without ECR plasma) assisted MOCVD. Sr(TMI-D)2 and Ti-isopropoxide were used as Sr and Ti metal organic sources, respectively. Perovskite SrTiO3 films were obtained at relatively low temperature of 500°C (using ECR oxygen plasma. Experimental results indicated that higher deposition temperature and ECR oxygen plasma increase the crystallinity, the dielectric constant and the leakage current density. The dielectric constant and the dielectric loss were 222 and 0.04, respectively, for 1234 Å thin SrTiO3 film (Sr/(Sr+Ti)=0.5). The leakage current density was 3.78 × 10−7 A/cm2 at 1.0V, and the dielectric breakdown field was 0.57MV/cm. SEM analyses showed that SrTiO3 films have a uniform and fine grain structure. In terms of step coverage, a lateral step coverage of 50% at 0.8 μm step (the aspect ratio was 1) was obtained with the thickness uniformity of ± 0.5% and the composition uniformity of ±1.2% at 4′′ wafer.

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