APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

2 Oct 2006

Volume 89, Issue 14, Articles (14xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 89, 142101 (2006); http://dx.doi.org/10.1063/1.2358202 (3 pages)

H. C. Lin, P. D. Ye, Y. Xuan, G. Lu, A. Facchetti, and T. J. Marks
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Growth and control of microscale to nanoscale carbon nitride particles

H. Y. Li, Y. C. Shi, and P. X. Feng

Appl. Phys. Lett. 89, 142901 (2006); http://dx.doi.org/10.1063/1.2355470 (3 pages) | Cited 6 times

Online Publication Date: 2 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Microscale to nanoscale carbon nitride (CN) particles are prepared using plasma sputtering deposition techniques. The preferred orientation of nanoscale CN particle distributions is obtained. Particles are examined using scanning electron microscopy (SEM) and Raman scattering spectroscopy. SEM micrographs show that the CN particles are spherical with nearly the same diameters of 2.5 μm prepared without setting bias voltage. The distribution of these particles is random. Setting bias voltage up to 5 kV, plasma sputtering deposition yields several dispersed ring patterns of particle distributions where many small groups of nanoscale particles are observed. Each group of these particles is in a sunflower type of distribution, in which the biggest (85 nm) particle at the center is surrounded by many small sizes (30 nm) of CN particles. Disk type of the particles with a diameter of 10 μm is also observed at different deposition conditions. Typical carbon bands and CN band in the Raman spectra of the samples are identified. The intensity of the bands obviously varies at the different deposition conditions.
Show PACS
81.07.Bc Nanocrystalline materials
61.46.Df Structure of nanocrystals and nanoparticles ("colloidal" quantum dots but not gate-isolated embedded quantum dots)
81.15.Cd Deposition by sputtering
52.77.Dq Plasma-based ion implantation and deposition
68.37.Hk Scanning electron microscopy (SEM) (including EBIC)
78.30.Hv Other nonmetallic inorganics

Dielectric constant enhancement due to Si incorporation into HfO2

Kazuyuki Tomida, Koji Kita, and Akira Toriumi

Appl. Phys. Lett. 89, 142902 (2006); http://dx.doi.org/10.1063/1.2355471 (3 pages) | Cited 60 times

Online Publication Date: 2 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors investigated the dielectric constant change of Hf(1−x)SixO2 film as functions of Si concentration and annealing temperature. As a result, the dielectric constant of Hf(1−x)SixO2 was increased when doped with a small amount of Si after 800 °C annealing. The authors revealed that the dielectric constant enhancement of Hf(1−x)SixO2 films is related to the phase transformation from the monoclinic to the tetragonal phase of HfO2. By using the Clausius-Mossotti relation, it is concluded that the dielectric constant enhancement through the structural phase transformation is derived from the molar volume shrinkage rather than the molar polarizability increase.
Show PACS
77.84.Bw Elements, oxides, nitrides, borides, carbides, chalcogenides, etc.
77.22.Ch Permittivity (dielectric function)
77.55.-g Dielectric thin films
81.40.Gh Other heat and thermomechanical treatments
64.70.K- Solid-solid transitions

Efficient dispersion relations for terahertz spectroscopy

E. Gornov, K.-E. Peiponen, Y. Svirko, Y. Ino, and M. Kuwata-Gonokami

Appl. Phys. Lett. 89, 142903 (2006); http://dx.doi.org/10.1063/1.2358814 (3 pages) | Cited 4 times

Online Publication Date: 2 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors introduce dispersion relations that provide an efficient tool in analysis of the experimental data in reflection terahertz spectroscopy when both the real and imaginary parts of the response function can be measured. These dispersion relations allow one to check the consistency of the measured spectra of the real and imaginary parts of the complex reflection coefficient, and moreover to remove the sample misplacement error from the measured spectra.
Show PACS
78.70.Gq Microwave and radio-frequency interactions

Experiment and first principles investigation on the hydrogen-hindered phase transition of ferroelectric ceramics

H. Y. Huang, W. Y. Chu, Y. J. Su, J. X. Li, L. J. Qiao, and S. Q. Shi

Appl. Phys. Lett. 89, 142904 (2006); http://dx.doi.org/10.1063/1.2358289 (3 pages) | Cited 3 times

Online Publication Date: 3 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, hydrogen-hindered phase transition of ferroelectric ceramics from cubic to tetragonal has been studied by experiment and first principles calculation. The calculation shows that for hydrogenated tetragonal PbTiO3, double-lowest-energy sites of Ti along the c axis exist no longer and the only lowest energy site locates at the center of the cell. The calculation can explain the experiment that hydrogen charged above its Curie temperature can hinder phase transition of lead zirconate titanate from cubic paraelectricity to tetragonal ferroelectricity.
Show PACS
64.70.K- Solid-solid transitions
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.80.B- Phase transitions and Curie point

Dielectric properties and abnormal C-V characteristics of Ba0.5Sr0.5TiO3–Bi1.5ZnNb1.5O7 composite thin films grown on MgO (001) substrates by pulsed laser deposition

Huyong Tian, Yu Wang, Danyang Wang, Jun Miao, Jianquan Qi, H. L. W. Chan, and C. L. Choy

Appl. Phys. Lett. 89, 142905 (2006); http://dx.doi.org/10.1063/1.2358934 (3 pages) | Cited 8 times

Online Publication Date: 3 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Highly c-axis oriented Ba0.5Sr0.5TiO3-based composite thin films were grown on MgO (001) single-crystal substrates by pulsed laser deposition and the in-plane dielectric properties of the films evaluated. X-ray diffraction characterization revealed a good crystallinity. The dielectric constant and loss were found to be 200 and 0.001–0.007 at room temperature, respectively. The butterfly-shaped C-V characteristic curve evidenced an enhanced in-plane dielectric tunability of >90% in the films at 1 MHz under a dc bias field of 0.8 MV/cm. A brief discussion is given on the abnormal C-V curves. Various tunable microwave applications of Ba0.5Sr0.5TiO3–Bi1.5ZnNb1.5O7 composite thin films are expected.
Show PACS
77.84.Lf Composite materials
77.55.-g Dielectric thin films
77.80.-e Ferroelectricity and antiferroelectricity
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.22.Ch Permittivity (dielectric function)
77.22.Gm Dielectric loss and relaxation

Thermal stability of LiTaO3 domains engineered by scanning force microscopy

Xiaoyan Liu, Kenji Kitamura, and Kazuya Terabe

Appl. Phys. Lett. 89, 142906 (2006); http://dx.doi.org/10.1063/1.2357556 (3 pages) | Cited 12 times

Online Publication Date: 4 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The stability of domains engineered in near-stoichiometric and congruent composition LiTaO3 crystals was investigated after heat treatment using scanning force microscopy. Piezoresponse images of the domains showed that the heat treatment had induced backswitching in the near-stoichiometric crystals and that the degree of backswitching depended on the domain structure and heating temperature. No backswitching was observed in the congruent composition crystals after the same heat treatment. The thermal stability of engineered LiTaO3 domains thus depends on the number of nonstoichiometric defects, the domain wall energy, and the pyroelectric effect.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.80.Dj Domain structure; hysteresis
77.80.Fm Switching phenomena
77.65.-j Piezoelectricity and electromechanical effects
77.70.+a Pyroelectric and electrocaloric effects
81.40.Gh Other heat and thermomechanical treatments

Interfacial chemical structure of HfO2/Si film fabricated by sputtering

Ran Jiang, Erqing Xie, and Zhenfang Wang

Appl. Phys. Lett. 89, 142907 (2006); http://dx.doi.org/10.1063/1.2358841 (3 pages) | Cited 19 times

Online Publication Date: 4 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The interfacial structure for HfO2 dielectrics on Si (100) substrate was investigated using x-ray photoelectron spectroscopy. The Hf 4f binding energy changes with the depth, which confirms the presence of Hf–O–Si state. Together with the analysis of O 1s and Si 2p spectra, it is believed that the interfacial structure includes both SiOx and Hf silicates. The electrical measurement is also consistent with the above conclusions. According to the theoretical and experimental results, a cursory model of the interfacial structure was established: The main body is SiOx species, on the top of SiOx is HfSixOy species, and Hf silicides are embedded in the Hf silicates.
Show PACS
68.35.Ct Interface structure and roughness
73.61.Ng Insulators
77.55.-g Dielectric thin films
81.15.Cd Deposition by sputtering
79.60.Bm Clean metal, semiconductor, and insulator surfaces

Change in phase separation and electronic structure of nitrided Hf-silicate films as a function of composition and post-nitridation anneal

M.-H. Cho, K. B. Chung, and D.-H. Ko

Appl. Phys. Lett. 89, 142908 (2006); http://dx.doi.org/10.1063/1.2355478 (3 pages) | Cited 6 times

Online Publication Date: 4 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The thermal stability and electronic structure of nitrided xHfO2∙(100−x)SiO2 (HfSiO) (x = 25%, 50%, and 75%), prepared using an NH3 annealing treatment, were investigated. The quantity of N incorporated into the Hf-silicate film was dependent on the mole fraction of SiO2 in the film: i.e., a silicate film containing a high mole fraction of SiO2 contained a higher quantity of N, resulting in the suppression of phase separation. In particular, the incorporated N easily diffuses out through a silicate film that contains a small quantity of SiO2 during the post-nitridation anneal, while in a film with a high quantity of SiO2, it is relatively stable. The phase separation effect in the nitrided film with a low SiO2 mole fraction was significantly influenced by the stability of N in the film and interface.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
64.75.-g Phase equilibria
71.20.Ps Other inorganic compounds
81.65.Lp Surface hardening: nitridation, carburization, carbonitridation
78.70.Dm X-ray absorption spectra
77.55.-g Dielectric thin films

Fluorine passivation in poly-Si/TaN/HfO2 through ion implantation

M. H. Zhang, F. Zhu, T. Lee, H. S. Kim, I. J. Ok, G. Thareja, L. Yu, and Jack C. Lee

Appl. Phys. Lett. 89, 142909 (2006); http://dx.doi.org/10.1063/1.2358950 (2 pages) | Cited 1 time

Online Publication Date: 4 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Fluorine (F) passivation in poly-Si/TaN/HfO2/p-Si gate stacks through gate ion implantation has been studied. It has been found that when the TaN thickness was less than 15 nm, the mobility and subthreshold swing improved significantly in HfO2 n-channel metal-oxide-semiconductor field effect transistors. Cross-section electron energy loss spectroscopy mapping shows that F atoms were distributed in both TaN and HfO2 layers, indicating that it is necessary to have a thin TaN layer.
Show PACS
85.30.Tv Field effect devices
85.40.Ry Impurity doping, diffusion and ion implantation technology
81.65.Rv Passivation

Defect control for low leakage current in K0.5Na0.5NbO3 single crystals

Yoichi Kizaki, Yuji Noguchi, and Masaru Miyayama

Appl. Phys. Lett. 89, 142910 (2006); http://dx.doi.org/10.1063/1.2357859 (3 pages) | Cited 44 times

Online Publication Date: 4 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Leakage current properties of K0.5Na0.5NbO3 (KNN) single crystals grown by a flux method have been investigated to establish a guiding principle of defect control for high-performance lead-free piezoelectric devices. The substitution of Mn at the Nb site and the following annealing under moderate oxidation condition was effective for suppressing leakage current of KNN crystals. Electron spin resonance measurements demonstrate that oxidation of Mn during annealing plays an essential role in low leakage current in the KNN system. Mn-doped KNN crystals exhibited a low leakage current density ( ∼ 10−8 A/cm2) and relatively large remanent polarization of 40 μC/cm2 at 25 °C.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.80.-e Ferroelectricity and antiferroelectricity
77.22.Ej Polarization and depolarization
81.10.Dn Growth from solutions
81.40.Gh Other heat and thermomechanical treatments
61.72.up Other materials

Effect of CaRuO3 interlayer on the dielectric properties of Ba(Zr,Ti)O3 thin films prepared by pulsed laser deposition

X. G. Tang, H. Y. Tian, J. Wang, K. H. Wong, and H. L. W. Chan

Appl. Phys. Lett. 89, 142911 (2006); http://dx.doi.org/10.1063/1.2360177 (3 pages) | Cited 17 times

Online Publication Date: 5 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Ba(Zr0.2Ti0.8)O3 (BZT) thin films on Pt(111)/Ti/SiO2/Si(100) substrates without and with CaRuO3 (CRO) buffer layer were fabricated at 650 °C in situ by pulsed laser deposition. The BZT thin films showed a dense morphology, many clusters are found on the surface images of BZT/Pt films, which are composed by nanosized grains of 25–35 nm; the average grain size of BZT/CRO films is about 80 nm, which lager than that of BZT/Pt thin film. The dielectric constants and dissipation factors of BZT/Pt and BZT/CRO thin films were 392 and 0.019 and 479 and 0.021 at 1 MHz, respectively. The dielectric constant of BZT/Pt and BZT/CRO thin films changes significantly with applied dc bias field and has high tunabilities and figures of merit of ∼ 70% and 37 and 75% and 36, respectively, under an applied field of 400 kV/cm. The possible microstructural background responsible for the high dielectric constant and tunability was discussed.
Show PACS
77.55.-g Dielectric thin films
77.22.Ch Permittivity (dielectric function)
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
81.15.Fg Pulsed laser ablation deposition
68.55.-a Thin film structure and morphology

Chemical states and electrical properties of a high-k metal oxide/silicon interface with oxygen-gettering titanium-metal-overlayer

Kang-Ill Seo, Dong-Ick Lee, Piero Pianetta, Hyoungsub Kim, Krishna C. Saraswat, and Paul C. McIntyre

Appl. Phys. Lett. 89, 142912 (2006); http://dx.doi.org/10.1063/1.2358834 (3 pages) | Cited 14 times

Online Publication Date: 5 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report on the chemical bonding structure of the HfO2/Si (001) stack after the SiO2 interfacial layer (IL) is partially removed by a reactive titanium metal overlayer. Using synchrotron photoelectron spectroscopy, they found that ultrathin SiO2-like IL ∼ 6.5 Å thick, which is significantly less than the initial SiO2 IL thickness of ∼ 15 Å, exists at the HfO2/Si interface with an overlying Ti electrode. The dissociated Si from SiO2 IL is believed to go onto Si substrate where it regrows epitaxially. The interfacial trap density of the Ti-electrode sample was extracted to be ∼ 1.6×1011 eV−1 cm−2 near the midgap of Si, which was comparable to that of the control sample with W electrode.
Show PACS
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
61.50.Lt Crystal binding; cohesive energy
61.72.Yx Interaction between different crystal defects; gettering effect
82.80.Pv Electron spectroscopy (X-ray photoelectron (XPS), Auger electron spectroscopy (AES), etc.)

Large piezoelectric strains from polarization graded ferroelectrics

S. Zhong, Z.-G. Ban, S. P. Alpay, and J. V. Mantese

Appl. Phys. Lett. 89, 142913 (2006); http://dx.doi.org/10.1063/1.2358963 (3 pages) | Cited 18 times

Online Publication Date: 5 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The potential applications of polarization graded ferroelectrics as high performance sensors and actuators are theoretically investigated. A static bending can be expected in polarization graded ferroelectric plates, forming a vertical displacement. This is due to the built-in strain gradient that arises from the grading of the composition and concomitantly, the spontaneous self-strain. Numerical results of two compositionally graded ferroelectrics, BaTiO3–Ba1−xSrxTiO3 and PbTiO3–Pb1−xZrxTiO3, show a high dynamic response of the displacement under an external electric field, yielding as much as ∼ 23% strain at 50 kV/cm in PbTiO3–Pb0.6Zr0.4TiO3, which is comparable to large displacement actuators formed from ceramic/ceramic and ceramic/metal multilayer mesomaterials.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.65.Ly Strain-induced piezoelectric fields
81.40.Lm Deformation, plasticity, and creep
62.20.F- Deformation and plasticity
77.22.Ej Polarization and depolarization
77.80.-e Ferroelectricity and antiferroelectricity

Defect passivation in HfO2 gate oxide by fluorine

K. Tse and J. Robertson

Appl. Phys. Lett. 89, 142914 (2006); http://dx.doi.org/10.1063/1.2360190 (3 pages) | Cited 22 times

Online Publication Date: 6 October 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors have calculated that fluorine substituting for oxygen gives no gap states in HfO2. This accounts for the good passivation of oxygen vacancies by F seen experimentally. Bonding arguments are used to account for why F may be the most effective passivant in ionic oxides such as HfO2, whereas hydrogen is effective in covalent solids. General principles of defect passivation in ionic oxides are discussed. Vacancies are more detrimental in ionic oxides than in SiO2 because they are more likely to be charged in the presence of a gate electrode.
Show PACS
81.65.Rv Passivation
61.72.J- Point defects and defect clusters
71.55.Ht Other nonmetals
77.55.-g Dielectric thin films
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close