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

3 Dec 2012

Volume 101, Issue 23, Articles (23xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 101, 233101 (2012); http://dx.doi.org/10.1063/1.4749281 (3 pages)

S. A. Studenikin, J. Thorgrimson, G. C. Aers, A. Kam, P. Zawadzki, Z. R. Wasilewski, A. Bogan, and A. S. Sachrajda
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Efficient counter-propagating wave acoustic micro-particle manipulation

A. Grinenko, C. K. Ong, C. R. P. Courtney, P. D. Wilcox, and B. W. Drinkwater

Appl. Phys. Lett. 101, 233501 (2012); http://dx.doi.org/10.1063/1.4769092 (3 pages)

Online Publication Date: 3 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A simple acoustic system consisting of a pair of parallel singe layered piezoelectric transducers submerged in a fluid used to form standing waves by a superposition of two counter-propagating waves is reported. The nodal positions of the standing wave are controlled by applying a variable phase difference to the transducers. This system was used to manipulate polystyrene micro-beads trapped at the nodal positions of the standing wave. The demonstrated good manipulation capability of the system is based on a lowering of the reflection coefficient in a narrow frequency band near the through-thickness resonance of the transducer plates.
Show PACS
43.38.Fx Piezoelectric and ferroelectric transducers
43.25.Jh Reflection, refraction, interference, scattering, and diffraction of intense sound waves
43.25.Gf Standing waves; resonance

An electrically switchable surface free energy on a liquid crystal and polymer composite film

Yi-Hsin Lin, Ting-Yu Chu, Yu-Shih Tsou, Kai-Han Chang, and Ya-Ping Chiu

Appl. Phys. Lett. 101, 233502 (2012); http://dx.doi.org/10.1063/1.4769093 (4 pages)

Online Publication Date: 4 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An electrically switchable surface free energy on a liquid crystal and polymer composite film (LCPCF) resulting from the orientations of liquid crystal molecules is investigated. By modification of Cassie’s model and the measurement based on the Chibowski’s film pressure model (E. Chibowski, Adv. Colloid Interface Sci. 103, 149 (2003)), the surface free energy of LCPCF is electrically switchable from 36×10−3J/m2 to 51×10−3J/m2 while the average tilt angle of LC molecules changes from 0° to 32° with the applied pulsed voltage. The switchable surface free energy of LCPCF can help us to design biosensors and photonics devices, such as electro-optical switches, blood sensors, and sperm testers.
Show PACS
68.35.Md Surface thermodynamics, surface energies
65.40.gp Surface energy
65.60.+a Thermal properties of amorphous solids and glasses: heat capacity, thermal expansion, etc.
61.30.Hn Surface phenomena: alignment, anchoring, anchoring transitions, surface-induced layering, surface-induced ordering, wetting, prewetting transitions, and wetting transitions
42.70.Df Liquid crystals

Characterization of InSb quantum wells with atomic layer deposited gate dielectrics

M. M. Uddin, H. W. Liu, K. F. Yang, K. Nagase, T. D. Mishima, M. B. Santos, and Y. Hirayama

Appl. Phys. Lett. 101, 233503 (2012); http://dx.doi.org/10.1063/1.4769225 (4 pages)

Online Publication Date: 5 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report magnetotransport measurements of a gated InSb quantum well (QW) with high quality Al2O3 dielectrics (40 nm thick) grown by atomic layer deposition. The magnetoresistance data demonstrate a parallel conduction channel in the sample at zero gate voltage (Vg). A good interface between Al2O3 and the top InSb layer ensures that the parallel channel is depleted at negative Vg and the density of two-dimensional electrons in the QW is tuned by Vg with a large ratio of 6.5 × 1014 m−2 V−1 but saturates at large negative Vg. These findings are closely related to layer structures of the QW as suggested by self-consistent Schrödinger-Poisson simulation and two-carrier model.
Show PACS
72.20.My Galvanomagnetic and other magnetotransport effects
73.21.Fg Quantum wells
81.07.St Quantum wells
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Surface doping in T6/PDI-8CN2 heterostructures investigated by transport and photoemission measurements

L. Aversa, R. Verucchi, R. Tatti, F. V. Di Girolamo, M. Barra, F. Ciccullo, A. Cassinese, and S. Iannotta

Appl. Phys. Lett. 101, 233504 (2012); http://dx.doi.org/10.1063/1.4769345 (5 pages)

Online Publication Date: 5 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this paper, we discuss the surface doping in sexithiophene (T6) organic field-effect transistors by N,N′-bis (n-octyl)-dicyanoperylenediimide (PDI-8CN2). We show that an accumulation heterojunction is formed at the interface between the organic semiconductors and that the consequent band bending in T6 caused by PDI-8CN2 deposition can be addressed as the cause of the surface doping in T6 transistors. Several evidences of this phenomenon have been furnished both by electrical transport and photoemission measurements, namely, the increase in the conductivity, the shift of the threshold voltage, and the shift of the T6 highest occupied molecular orbital peak towards higher binding energies.
Show PACS
85.30.Tv Field effect devices

Toward terahertz heterodyne detection with superconducting Josephson junctions

M. Malnou, A. Luo, T. Wolf, Y. Wang, C. Feuillet-Palma, C. Ulysse, G. Faini, P. Febvre, M. Sirena, J. Lesueur, and N. Bergeal

Appl. Phys. Lett. 101, 233505 (2012); http://dx.doi.org/10.1063/1.4769441 (4 pages)

Online Publication Date: 5 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the high-frequency mixing properties of ion irradiated YBa2Cu3O7 Josephson junctions. The frequency range, spanning above and below the characteristic frequencies fc of the junctions, permits a clear observation of the transition between two mixing regimes. The experimental conversion gain was found to be in good agreement with the prediction of the three-port model. Finally, we discuss the potential of the junctions to build a Josephson mixer operating in the terahertz frequency range.
Show PACS
85.25.Cp Josephson devices

Precise relationship between voltage and frequency at the appearance of negative capacitance in InGaN diodes

L. F. Feng, Y. Li, D. Li, X. D. Hu, W. Yang, C. D. Wang, and Q. Y. Xing

Appl. Phys. Lett. 101, 233506 (2012); http://dx.doi.org/10.1063/1.4769807 (4 pages)

Online Publication Date: 5 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The exact relationship between voltage and frequency when negative capacitance (NC) appears in light-emitting diodes containing InGaN was determined both experimentally and by solving the physical equations for the complete equivalent circuit of a symmetrical p-n junction combined with its boundary condition. Results from the calculation revealed that NC depends on the recombination lifetime of carriers; therefore, we can accurately determine recombination lifetime from the appearance of NC.
Show PACS
85.60.Jb Light-emitting devices

Current conduction and stability of CeO2/La2O3 stacked gate dielectric

Hei Wong, B. L. Yang, Shurong Dong, H. Iwai, K. Kakushima, and P. Ahmet

Appl. Phys. Lett. 101, 233507 (2012); http://dx.doi.org/10.1063/1.4768943 (3 pages) | Cited 1 time

Online Publication Date: 6 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The current conduction behaviors in CeO2/La2O3 stack are studied. We found that large amount of hole injection under large negative gate bias can give rise to the accumulation of neutral interstitial oxygen (OI) species which serve as acceptors and promotes the hole conduction in the La2O3 film. Whereas if the amount of hole injection is lower than that of the oxygen anions injected from the capping CeO2 layer under a sufficient large negative gate bias, the amount of OI reduces and a negative charge built-up results which further reduces the leakage current and threshold voltage of p-channel metal-oxide-semiconductor transistors.
Show PACS
85.75.Hh Spin polarized field effect transistors
82.45.Un Dielectric materials in electrochemistry
85.30.Tv Field effect devices

Acoustic focusing by coiling up space

Yong Li, Bin Liang, Xu Tao, Xue-feng Zhu, Xin-ye Zou, and Jian-chun Cheng

Appl. Phys. Lett. 101, 233508 (2012); http://dx.doi.org/10.1063/1.4769984 (5 pages)

Online Publication Date: 6 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the design of a gradient index acoustic lens by coiling up space, an entirely different, yet more direct approach compared with previous designs. The proposed model comprises a series of acoustic metamaterial units with curled channels. Acoustic waves propagate freely within the channels but their propagating phases can be delayed at will by adjusting the size of the units. The numerical results show that the designed acoustic metamaterial can mimic an acoustic gradient index lens with arbitrarily large refractive index and considerably high transmission efficiency. This may provide possibilities for the design and application of acoustic lenses.
Show PACS
43.20.El Reflection, refraction, diffraction of acoustic waves

Analysis of anomalous traps measured by charge pumping technique in HfO2/metal gate n-channel metal-oxide-semiconductor field-effect transistors

Szu-Han Ho, Ting-Chang Chang, Ying-shin Lu, Wen-Hung Lo, Ching-En Chen, Jyun-Yu Tsai, Hua-Mao Chen, Chi-Wei Wu, Hung-Ping Luo, Guan-Ru Liu, Tseung-Yuen Tseng, Osbert Cheng, Cheng-Tung Huang, and Simon M. Sze

Appl. Phys. Lett. 101, 233509 (2012); http://dx.doi.org/10.1063/1.4769444 (4 pages)

Online Publication Date: 7 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This letter investigates anomalous traps measured by charge pumping technique in high voltage in HfO2/metal gate n-channel metal-oxide-semiconductor field-effect transistors. N-Vhigh level characteristic curves with different duty ratios indicate that the electron discharge time dominates the value of N for extra traps. By fitting ln (N (tbase level = 2.5μs)-N (tbase level))-Δtbase level at different temperatures and computing the equation t = τ0 exp (αe,SiO2d SiO2 + αe,HfO2d HfO2,trap), results show that these extra traps measured by the charge pumping technique at high voltage can be attributed to high-k bulk shallow traps.
Show PACS
85.30.Tv Field effect devices

Charge loss mechanism of non-volatile V3Si nano-particles memory device

Dongwook Kim, Dong Uk Lee, Eun Kyu Kim, and Won-Ju Cho

Appl. Phys. Lett. 101, 233510 (2012); http://dx.doi.org/10.1063/1.4770060 (4 pages)

Online Publication Date: 7 December 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We studied the charge loss mechanism of a non-volatile memory device with vanadium silicide (V3Si) nano-particles (NPs) embedded in a silicon dioxide dielectric layer. To fabricate the memory device, V3Si NPs with an average size of 4–6 nm were formed between the tunnel and control oxide layers by a thin film deposition and a post-annealing process at 800  °C for 5 s. Using the gate structure containing the V3Si NPs, a flash memory structure was fabricated with a channel length and width of 5 μm. This device maintained the memory window at about 1 V after 104 s when program/erase voltages of ±9 V were applied for 1 s. The activation energies of the V3Si NP memory devices with charge loss rates of 10%, 15%, 20%, and 25% were approximately 0.16, 0.24, 0.35, and 0.50 eV, respectively. The charge loss mechanism can be attributed to direct tunneling as a result of the NPs associating with the interface trap in the tunneling oxide, the Pool-Frenkel current, and the oxide defect.
Show PACS
84.30.Sk Pulse and digital circuits
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close