Electrical Properties and Film Structures of (BaxSr1−x)TiO3 Thin Films by RF Sputtering

ABSTRACTThin films of (BaxSrj-x)TiO3 (BST) deposited by RF sputtering have been studied for the application to the capacitor material of dynamic random access memory (DRAM). The effects of film structures on the dielectric constant and the leakage current were investigated. The films deposited at 550–600°C consist of granular grains, and the films deposited above 650°C contain columnar grains. The dielectric constant is related to the grain size in the direction of thickness. The leakage current increases as the film structure changes from granular to columnar. The low leakage current (less than 10−8 A/cm2 at +2 and -2 V) and the small value of equivalent SiO2 thickness (0.9 nm) were attained in the (Ba065Sr035) TiO3 thin films.

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Low Temperature Deposition of High Dielectric Constant Thin Films for Decoupling Capacitor Applications

MRS Proceedings ◽

10.1557/proc-203-315 ◽

1990 ◽

Vol 203 ◽

Author(s):

P. Li ◽

B. Gittleman ◽

T.-M. Lu

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Leakage Current ◽

High Dielectric Constant ◽

Promising Alternative ◽

Low Leakage ◽

Low Leakage Current ◽

Annealing Effects ◽

Temperature Deposition ◽

High Dielectric

ABSTRACTHigh dielectric constant thin films for packaging applications were studied. Compared with polycrystalline or epitaxial ferroelectric thin films amorphous ferroelectric films are a promising alternative because of their ease of processing and low leakage current. Reactive Partially Ionized Beam deposition (RPIB) offers a new approach to deposit high dielectric constant films at a low substrate temperature. As an example, the growth of amorphous BaTiOs thin films using RPIB deposition is described. The films were characterized in terms of dielectric constant and leakage current. The annealing effects on the film properties are also discussed.

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Effect of La Contents on La-Doped Bi2Ti2O7 Dielectric Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.931 ◽

2013 ◽

Vol 750-752 ◽

pp. 931-935

Author(s):

Xue Na Yang ◽

Jian An Liu ◽

Bai Biao Huang ◽

Si Jiang Gao

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Leakage Current ◽

High Dielectric Constant ◽

Dielectric Thin Films ◽

Low Leakage ◽

Low Leakage Current ◽

Xrd Patterns ◽

High Dielectric ◽

La Doped

La-doped (Bi1-xLax)2Ti2O7 (BLTO) thin films with different La contents have been grown by CSD method. All the XRD patterns of the samples showed that the films were polycrystalline films. The intensities of the peaks decreased with the increasing of La contents. The general trend of the changes of leakage current was decreased with the increasing of x. The case of dielectric constant as a function of La content is complicated. The rule of change of the dielectric constant is different with different la contents. In view of dielectric constant and dielectric loss, we think that the film of x=0.2 has relative low leakage current and high dielectric constant, which is considered to be adequate for a DRAM.

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Structural and Electrical Properties of BaTio3 Thin Films Grown on p-Si Substrates with Different Device Designs

MRS Proceedings ◽

10.1557/proc-318-501 ◽

1993 ◽

Vol 318 ◽

Cited By ~ 1

Author(s):

L. H. Chang ◽

Q. X. Jia ◽

W. A. Anderson

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Leakage Current ◽

Single Layer ◽

Relative Dielectric Constant ◽

Rf Magnetron Sputtering ◽

Phonon Modes ◽

Si Substrates ◽

Low Leakage ◽

Low Leakage Current

ABSTRACTRF magnetron sputtering of BaTiO3 on (100) p-Si was performed to produce a high-quality BaTiO3/p-Si interface and BaTi03 insulator gates with high dielectric constant and low leakage current. Through different processing and device designs, different capacitor structures, including single layer amorphous, single layer polycrystalline and bi-layer amorphous on polycrystal-line, were investigated in this study. Raman spectroscopy showed the optical phonon modes of the BaTiO3 thin films with different structures. The structural properties of the films were characterized by X-ray diffraction. Using both the quasistatic and the high-frequency capacitance-voltage measurements, the interface-trap density was estimated at high 1011 eV−1 cm−2. The relative dielectric constant of the composite structure was controlled in a range from 30 to 130. The leakage current density was as low as 8×10−10 A/cm2 at a field intensity of (2±0.5)×105 V/cm. Breakdown voltage varied from 5x105 to 2×106 V/cm.

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Binary HfO2: SiO2 used as High-k Gate Oxide Material in Combinatorial Material Library Method

MRS Proceedings ◽

10.1557/proc-0894-ll03-30 ◽

2005 ◽

Vol 894 ◽

Cited By ~ 1

Author(s):

Wen-Hsuan Chao ◽

Lih-Ping Wang ◽

Shu-Huei Wang ◽

Tien-Heng Huang ◽

Ren-Jen Wu ◽

...

Keyword(s):

Dielectric Constant ◽

Electrical Properties ◽

Leakage Current ◽

Structural Characteristics ◽

Rf Sputtering ◽

Oxide Semiconductor ◽

Oxide Material ◽

Gate Oxides ◽

Low Leakage ◽

Low Leakage Current

AbstractHafnium silicates (HfO2:SiO2, HSO) have recently attracted much interest in the fields of fundamental science and technology because they have high dielectric constant and low leakage current. The structure and properties of HSO gate oxides were studied using a combinatorial continuous-compositional-spread method. HSO material libraries were synthesized on a 4-inch wafer at room temperature and at 200°C using a custom-built radio-frequency (RF) sputtering system. The electrical properties of HSO material libraries were measured using metal-oxide-semiconductor structure. X-ray diffraction (XRD) was utilized to characterize the structure and compositions of HSO material libraries. The effects of sputtering conditions on the properties of the HSO gate oxides were investigated. The dielectrics constants (εr) of HSO material libraries treated with rapid thermal annealing (600°C/1min/N2) were in the range 5∼23, as determined by C-V measurement, and the dielectric constant was observed to increase with HfO2 content. The I-V relations of the HSO material libraries indicate that the leakage current decreases as the amount of Si in the HSO films increases. The structural characteristics of HSO films with RTA treatment (1000°C/10sec/N2) varied from the amorphous to the crystalline state (tetragonal and monoclinic phase), according to the composition of material libraries. The correlation among the electrical properties, the composition and the crystal structure of the HSO films is discussed.

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High-κ Insulator Thin Films and Retention Properties of MFIS Diodes

MRS Proceedings ◽

10.1557/opl.2011.1398 ◽

2011 ◽

Vol 1345 ◽

Cited By ~ 1

Author(s):

Yichun Zhou

Keyword(s):

Thin Films ◽

Leakage Current ◽

High Speed ◽

Random Access ◽

Ferroelectric Thin Film ◽

Buffer Layers ◽

Interface Properties ◽

Si Substrate ◽

Device Structure ◽

Low Leakage

ABSTRACTFerroelectric field effect transistor (FFET) is a promising candidate for non-volatile random access memory because of its high speed, single device structure, low power consumption, and nondestructive read-out operation. Currently, however, such ideal devices are commercially not available due to poor interface properties between ferroelectric film and Si substrate, such as leakage current and interdiffusion etc. So we choose YSZ and HfO2 insulating thin films as buffer layer due to they possess relatively high dielectric constant, high thermal stability, low leakage current, and good interface property with Si substrates. Two structural diodes of Pt/BNT/YSZ/Si and Pt/SBT/HfO2/Si were fabricated, and the microstructures, interface properties, C-V, I-V, and retention properties were investigated in detail. Experimental results show that the fabricated diodes exhibit excellent long-term retention properties, which is due to the good interface and the low leakage density, demonstrating that the YSZ and HfO2 buffer layers are playing a critical modulation role between the ferroelectric thin film and Si substrate.

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Excellent Room-Temperature Ferroelectricity in Mn-substituted BiFeO3 Thin Films Formed by Chemical Solution DepositionΨ

MRS Proceedings ◽

10.1557/proc-0933-g03-03 ◽

2006 ◽

Vol 933 ◽

Author(s):

Sushil Kumar Singh ◽

Hiroshi Ishiwara

Keyword(s):

Thin Films ◽

Leakage Current ◽

Lattice Structure ◽

Hysteresis Loops ◽

Secondary Phase ◽

Low Leakage ◽

Low Leakage Current ◽

Chemical Solutions ◽

Mn Substitution ◽

Mn Doped

AbstractMn-substituted BiFeO3 (BFO) thin films were formed by chemical solutions deposition on Pt/Ti/SiO2/Si(100) structures. Effects of the Mn-substitution on the structure and ferroelectricity of BFO films were examined. We found that the lattice structure of the film is sensitive to the Mn-substitution and the secondary phase is appears in 50% Mn-substituted BFO films. The leakage current were increased with the Mn-substitution. However, the 5% Mn-substituted BFO film shows low leakage current than undoped BFO films in a high electric field than 0.5 MV/cm. Due to the low leakage current in Mn-doped 3, 5 and 7% BFO films, the saturated P-E hysteresis loops with remanent polarization around 100 μC/cm2 were obtained at RT.

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Low leakage current in (Bi0.95La0.05)2NiMnO6 double-perovskite thin films prepared by chemical solution deposition

Materials Letters ◽

10.1016/j.matlet.2014.01.025 ◽

2014 ◽

Vol 120 ◽

pp. 23-25 ◽

Cited By ~ 4

Author(s):

Wan-peng Li ◽

Qiu-xiang Liu ◽

Xin-gui Tang ◽

Ju-lan Lai ◽

Yan-ping Jiang

Keyword(s):

Thin Films ◽

Leakage Current ◽

Chemical Solution Deposition ◽

Double Perovskite ◽

Chemical Solution ◽

Solution Deposition ◽

Low Leakage ◽

Low Leakage Current

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Dielectric properties characterization of La- and Dy-doped BiFeO3 thin films

Journal of Materials Research ◽

10.1557/jmr.2007.0287 ◽

2007 ◽

Vol 22 (8) ◽

pp. 2179-2184 ◽

Cited By ~ 15

Author(s):

Peter Kr. Petrov ◽

Vaijayanti R. Palkar ◽

Alexander K Tagantsev ◽

Hsin-I Chien ◽

K. Prashanthi ◽

...

Keyword(s):

Magnetic Field ◽

Thin Films ◽

Electric Field ◽

Leakage Current ◽

Structural Features ◽

Type I ◽

Low Leakage ◽

Low Leakage Current ◽

Dc Electric Field ◽

Measuring Frequency

The dielectric response of La- and Dy- doped BiFeO3 thin films at microwave frequencies (up to 12 GHz) has been monitored as a function of frequency, direct current (dc) electric field, and magnetic field in a temperature range from 25 to 300 °C. Both the real and imaginary parts of the response have been found to be non-monotonic (oscillating) functions of measuring frequency. These oscillations are not particularly sensitive to a dc electric field; however, they are substantially dampened by a magnetic field. The same effect has been observed when the volume of the characterized sample is increased. This phenomenon is attributed to the presence of a limited number of structural features with a resonance type response. The exact origin of these features is unknown at present. Leakage current investigations were performed on the whole set of films. The films were highly resistive with low leakage current, thereby giving us confidence in the microwave measurements. These typically revealed ‘N’-type I-V characteristics.

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Low Dielectric Loss and Multiferroic Properties in Ferroelectric/Mutiferroic/Ferroelectric Sandwich Structured Thin Films

Coatings ◽

10.3390/coatings9080502 ◽

2019 ◽

Vol 9 (8) ◽

pp. 502

Author(s):

Zhi-Yong Wu ◽

Cai-Bin Ma

Keyword(s):

Thin Film ◽

Thin Films ◽

Room Temperature ◽

Bismuth Ferrite ◽

Ferroelectric Properties ◽

Rf Sputtering ◽

Low Dielectric ◽

Low Leakage ◽

Low Leakage Current ◽

Electronic Field

Bismuth ferrite (BiFeO3) has proven to be promising for a wide variety of microelectric and magnetoelectric devices applications. In this work, a dense (Ba0.65Sr0.35)TiO3(BST)/(Bi0.875Nd0.125)FeO3(BNF)/BST trilayered thin film grown on Pt-coated Si (100) substrates was developed by the rf-sputtering. For comparison, single-layered BNF and BST were also prepared on the same substrates, respectively. The results show that the dielectric loses suppression in BST/BNF/BST trilayered thin films at room temperature but has enhanced ferromagnetic and ferroelectric properties. The remnant polarization (Pr) and coercive electronic field (Ec) were 5.51 μC/cm2 and 18.3 kV/cm, and the remnant magnetization (Mr) and coercive magnetic field (Hc) were 10.1 emu/cm3 and 351 Oe, respectively, for the trilayered film. We considered that the bismuth’s volatilization was limited by BST bottom layers making the Bi/Fe in good station, and the action of BST layer in the charge transfer between BNF thin film and electrode led to the quite low leakage current and enhanced multiferroic property. The origin of the mechanism of the highly enhanced dielectric constant and decreased loss tanδ was discussed.

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