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

29 Aug 2011

Volume 99, Issue 9, Articles (09xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 99, 094101 (2011); http://dx.doi.org/10.1063/1.3629783 (3 pages)

Tomasz Szymborski, Piotr M. Korczyk, Robert Hołyst, and Piotr Garstecki
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Kilohertz magnetic field focusing in a pair of metallic periodic-ladder structures

Debasish Banerjee, Jaewook Lee, Ercan M. Dede, and Hideo Iizuka

Appl. Phys. Lett. 99, 093501 (2011); http://dx.doi.org/10.1063/1.3629992 (3 pages) | Cited 2 times

Online Publication Date: 29 August 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Here, we show, analytically and numerically, that in a pair of metallic periodic-ladder structures placed with a central gap, the normally incident magnetic field is focused on a spot of 3 mm (0.6 × 10−5 free space wavelength) full width at half maximum at a 1 mm distance away at 600 kHz. The ladder structures are designed by exploiting the curl of the induced current at each unit cell in the periodic structure. This investigation paves the way for kilohertz magnetic field manipulations.
Show PACS
41.20.Gz Magnetostatics; magnetic shielding, magnetic induction, boundary-value problems

Uncorrelated multiple conductive filament nucleation and rupture in ultra-thin high-κ dielectric based resistive random access memory

Xing Wu, Kun Li, Nagarajan Raghavan, Michel Bosman, Qing-Xiao Wang, Dongkyu Cha, Xi-Xiang Zhang, and Kin-Leong Pey

Appl. Phys. Lett. 99, 093502 (2011); http://dx.doi.org/10.1063/1.3624597 (3 pages) | Cited 4 times

Online Publication Date: 29 August 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Resistive switching in transition metal oxides could form the basis for next-generation non-volatile memory (NVM). It has been reported that the current in the high-conductivity state of several technologically relevant oxide materials flows through localized filaments, but these filaments have been characterized only individually, limiting our understanding of the possibility of multiple conductive filaments nucleation and rupture and the correlation kinetics of their evolution. In this study, direct visualization of uncorrelated multiple conductive filaments in ultra-thin HfO2-based high-κ dielectric resistive random access memory (RRAM) device has been achieved by high-resolution transmission electron microscopy (HRTEM), along with electron energy loss spectroscopy (EELS), for nanoscale chemical analysis. The locations of these multiple filaments are found to be spatially uncorrelated. The evolution of these microstructural changes and chemical properties of these filaments will provide a fundamental understanding of the switching mechanism for RRAM in thin oxide films and pave way for the investigation into improving the stability and scalability of switching memory devices.
Show PACS
84.30.Sk Pulse and digital circuits

Induced static magnetic field by a cellular phone

M. Einat and A. Yahalom

Appl. Phys. Lett. 99, 093503 (2011); http://dx.doi.org/10.1063/1.3632081 (3 pages) | Cited 1 time

Online Publication Date: 31 August 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Recent claims regarding the safety of cellular phones suggest that weak static magnetic fields are induced around the phone, and this field and its gradients may pose a health risk to the user. An experiment was conducted to measure the induced static magnetic field around a cellular phone. 65 μT variations and 18 μT/cm gradients were measured in the magnetic field at 6 cm from the phone. An analytical model is derived to explain the results. The influence that the measured magnetic fields may have on the user is beyond the scope of this research.
Show PACS
87.50.cf Biophysical mechanisms of interaction

Impact of In situ vacuum anneal and SiH4 treatment on electrical characteristics of AlGaN/GaN metal-oxide-semiconductor high-electron mobility transistors

Xinke Liu, Edwin Kim Fong Low, Jisheng Pan, Wei Liu, Kie Leong Teo, Leng-Seow Tan, and Yee-Chia Yeo

Appl. Phys. Lett. 99, 093504 (2011); http://dx.doi.org/10.1063/1.3633104 (3 pages) | Cited 1 time

Online Publication Date: 1 September 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effect of in situ vacuum anneal (VA) and silane (SiH4) treatment on the electrical characteristics of AlGaN/GaN metal-oxide-semiconductor high-electron mobility transistors was investigated. Native Ga-O bonds on the AlGaN surface can be completely removed by this in situ passivation technique, which was confirmed by x-ray photoelectron spectroscopy. In situ VA and SiH4 passivation also reduced the device gate leakage current. This is attributed to the suppression of trap-assisted tunneling current through the HfAlO gate dielectric. Saturation drain current for devices with in situ VA and SiH4 passivation was also improved, which is due to increased two-dimensional electron gas density. In addition, devices with in situ VA and SiH4 passivation achieved an Ion/Ioff ratio of around 106 and a subthreshold swing of less than 100 mV/decade.
Show PACS
85.30.Tv Field effect devices
85.30.De Semiconductor-device characterization, design, and modeling

Extraction of voltage-dependent series resistance from I-V characteristics of Schottky diodes

Haziret Durmuş and Ülfet Atav

Appl. Phys. Lett. 99, 093505 (2011); http://dx.doi.org/10.1063/1.3633116 (3 pages)

Online Publication Date: 1 September 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A method for extracting the bias dependent behaviour of the series resistance of a Schottky barrier diode from experimental I-V data is presented. It was assumed that the behaviour of the Schottky barrier is well defined by thermionic emission theory. Relative merit of the method was determined by applying the method on some artificial sets of I-V data corresponding to known values of series resistances and comparing the results with existing methods.
Show PACS
85.30.Kk Junction diodes
85.30.Hi Surface barrier, boundary, and point contact devices
73.30.+y Surface double layers, Schottky barriers, and work functions
79.40.+z Thermionic emission

Investigation of the deep level involved in InGaN laser degradation by deep level transient spectroscopy

M. Meneghini, C. de Santi, N. Trivellin, K. Orita, S. Takigawa, T. Tanaka, D. Ueda, G. Meneghesso, and E. Zanoni

Appl. Phys. Lett. 99, 093506 (2011); http://dx.doi.org/10.1063/1.3626280 (3 pages)

Online Publication Date: 2 September 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This paper reports an extensive analysis of the properties of the deep level responsible for the degradation of InGaN-based laser diodes. The analysis is based on combined optical measurements and Deep-Level Transient Spectroscopy (DLTS) investigation. Results indicate that stress induces a significant increase in threshold current of the devices, which is strongly correlated to the increase in the concentration of a deep level (DL) detected by DLTS. The DL involved in the degradation process is located 0.35–0.45 eV below the conduction band. 2D simulation indicates that degradation occurs within the quantum-well region.
Show PACS
71.55.Eq III-V semiconductors
42.55.Px Semiconductor lasers; laser diodes

Effects of excess oxygen on operation characteristics of amorphous In-Ga-Zn-O thin-film transistors

Keisuke Ide, Yutomo Kikuchi, Kenji Nomura, Mutsumi Kimura, Toshio Kamiya, and Hideo Hosono

Appl. Phys. Lett. 99, 093507 (2011); http://dx.doi.org/10.1063/1.3633100 (3 pages) | Cited 6 times

Online Publication Date: 2 September 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Operation characteristics of amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) were improved to a subthreshold voltage swing (S) of 217 mV (decade)−1, a mobility of ∼11.4 cm2 (Vs)−1, and a threshold voltage (Vth) of 0.1 V by O3 annealing at a temperature as low as 150 °C. However, the O3 annealing at 300 °C caused serious deterioration and exhibited a bistable transition between a large S state and a large Vth state. This transition is attributed to incorporation of excess oxygen and associated subgap defects with a negative-U characteristic. It also explains why a-IGZO channels deposited at high oxygen pressures do not produce operating TFTs.
Show PACS
85.30.Tv Field effect devices
61.72.Cc Kinetics of defect formation and annealing

Role of surface orientation on atomic layer deposited Al2O3/GaAs interface structure and Fermi level pinning: A density functional theory study

Ganesh Hegde, Gerhard Klimeck, and Alejandro Strachan

Appl. Phys. Lett. 99, 093508 (2011); http://dx.doi.org/10.1063/1.3624897 (3 pages) | Cited 2 times

Online Publication Date: 2 September 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We investigate the initial surface reaction pathways in the atomic layer deposition (ALD) of Al2O3 on GaAs (111)A and (111)B substrates using precursors trimethylaluminum (TMA) and water to ascertain the effect of surface orientation on device performance. We find that the condition of the respective substrates prior to deposition of TMA and water has a major impact on the surface reactions that follow and on the resulting interface structure. The simulations explain the atomistic mechanism of the interfacial self-cleaning effect in ALD that preferentially removes As oxides. The electronic structure of the resulting atomic configurations indicates states throughout the bandgap for the (111)B structure. By contrast, the (111)A structure has no states in the mid-gap region, thus explaining the significant experimental difference in Fermi Level Pinning behavior for corresponding devices.
Show PACS
71.20.Ps Other inorganic compounds
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.35.Ct Interface structure and roughness
71.15.Mb Density functional theory, local density approximation, gradient and other corrections
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close