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

9 Apr 2001

Volume 78, Issue 15, pp. 2095-2255

Return to All Sections
back to top
RSS Feeds

Si single-electron transistors with in-plane point-contact metal gates

T. H. Wang, H. W. Li, and J. M. Zhou

Appl. Phys. Lett. 78, 2160 (2001); http://dx.doi.org/10.1063/1.1359777 (3 pages) | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the operation of Si single-electron transistors with in-plane point-contact metal gates. These in-plane gates are fabricated by a self-aligned process, which are used to squeeze the channel and to form a single dot at the constriction of the channel. The characteristics of such single-electron transistors strongly depend on the channel width and the voltage of the in-plane gates. A few dips are observed at the less positive gate voltages for a device with a 70 nm wide channel. Applying negative voltages to the in-plane gates leads to the formation of a single dot in the conducting channel. These in-plane gates facilitate fabricating Si single-electron transistors with single dot structures. © 2001 American Institute of Physics.
Show PACS
85.35.Gv Single electron devices
85.35.Be Quantum well devices (quantum dots, quantum wires, etc.)

Radiative recombination from InP quantum dots on (100) GaP

F. Hatami, W. T. Masselink, and L. Schrottke

Appl. Phys. Lett. 78, 2163 (2001); http://dx.doi.org/10.1063/1.1361277 (3 pages) | Cited 16 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We describe the growth and optical emission from strained InP quantum dots grown on GaP using gas-source molecular beam epitaxy. Self-organized island formation takes place for InP coverage greater than 1.8 monolayers on the (100) GaP surface. Intense photoluminescence from the dots is peaked at about 2.0 eV, blueshifted by 0.6 eV from the band gap of bulk InP due to strain, quantum size effects, and possibly Ga interdiffusion. © 2001 American Institute of Physics.
Show PACS
78.55.Cr III-V semiconductors
78.67.Hc Quantum dots
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
81.05.Ea III-V semiconductors
68.65.Hb Quantum dots (patterned in quantum wells)
81.07.Ta Quantum dots

Effects of Mg doping on photoelectrical properties of hydrogenated GaN films grown at 380 °C

Shigeru Yagi and Seiji Suzuki

Appl. Phys. Lett. 78, 2166 (2001); http://dx.doi.org/10.1063/1.1350900 (3 pages) | Cited 7 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effects of Mg doping on hydrogenated GaN films grown at 380 °C are investigated in terms of the photoelectrical properties of simple sandwich-type cells. The photocurrent increases with Mg until it reaches maximum and the dark current decreases monotonically with Mg doping. The photovoltaic current of the cells using transparent conductive glass substrates exhibits excellent linearity with an optical power. The peak responsivity at a 0 V bias is 0.02 A/W at 340 nm, which corresponds to an internal quantum efficiency of approximately 0.3. This simple cell functions as a visible-blind ultraviolet detector and also a transparent solar cell. © 2001 American Institute of Physics.
Show PACS
73.61.Ey III-V semiconductors
73.50.Pz Photoconduction and photovoltaic effects
84.60.Jt Photoelectric conversion
85.60.Gz Photodetectors (including infrared and CCD detectors)
61.72.uj III-V and II-VI semiconductors
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Mechanism of radio-frequency current collapse in GaN–AlGaN field-effect transistors

A. Tarakji, G. Simin, N. Ilinskaya, X. Hu, A. Kumar, A. Koudymov, J. Yang, M. Asif Khan, M. S. Shur, and R. Gaska

Appl. Phys. Lett. 78, 2169 (2001); http://dx.doi.org/10.1063/1.1363694 (3 pages) | Cited 57 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The mechanism of radio-frequency current collapse in GaN–AlGaN heterojunction field-effect transistors (HFETs) was investigated using a comparative study of HFET and metal–oxide–semiconductor HFET current–voltage (I–V) and transfer characteristics under dc and short-pulsed voltage biasing. Significant current collapse occurs when the gate voltage is pulsed, whereas under drain pulsing the I–V curves are close to those in steady-state conditions. Contrary to previous reports, we conclude that the transverse electric field across the wide-band-gap barrier layer separating the gate and the channel rather than the gate or surface leakage currents or high-field effects in the gate–drain spacing is responsible for the current collapse. We find that the microwave power degradation in GaN–AlGaN HFETs can be explained by the difference between dc and pulsed I–V characteristics. © 2001 American Institute of Physics.
Show PACS
85.30.Tv Field effect devices
84.40.-x Radiowave and microwave (including millimeter wave) technology
84.30.Jc Power electronics; power supply circuits

Low-noise GaN Schottky diodes on Si(111) by molecular beam epitaxy

Peter W. Deelman, Robert N. Bicknell-Tassius, Sergey Nikishin, Vladimir Kuryatkov, and Henryk Temkin

Appl. Phys. Lett. 78, 2172 (2001); http://dx.doi.org/10.1063/1.1357448 (3 pages) | Cited 12 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the achievement of mesa-isolated Schottky diodes fabricated from n-GaN epilayers grown by gas-source molecular beam epitaxy on Si(111) that exhibit extremely low noise and dark current. Silicon dioxide grown by plasma-enhanced chemical vapor deposition provided both surface passivation and electrical isolation, and the Schottky contact was a 10 nm Pd thin film. The dark current of an 86×86 μm2 diode was 2.10×10−8 A/cm2 at −2 V bias, and the zero-bias noise power density at 1 Hz is as low a 9×10−29 A2/Hz. © 2001 American Institute of Physics.
Show PACS
85.30.Kk Junction diodes
81.65.Rv Passivation
85.60.Gz Photodetectors (including infrared and CCD detectors)
85.60.Dw Photodiodes; phototransistors; photoresistors

Commensurability effects in lateral surface-doped superlattices

R. A. Deutschmann, C. Stocken, W. Wegscheider, M. Bichler, and G. Abstreiter

Appl. Phys. Lett. 78, 2175 (2001); http://dx.doi.org/10.1063/1.1362283 (3 pages) | Cited 1 time

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We fabricate density-modulated two-dimensional electron systems by shallow compensation doping the donor layer of a modulation-doped heterostructure. Zinc acceptor atoms are diffused from the sample surface which is heated by a focused laser beam. Low-temperature magnetotransport experiments provide evidence that high-quality lateral surface superlattices can be fabricated. In weak periodic one-dimensional potentials, commensurability oscillations are recovered, whereas in strong periodic two-dimensional potentials the semiclassically expected antidot resistance resonances are found to dominate the low-field transport. Additionally, the homogeneity of the laser-induced doping is confirmed by magnetic focusing experiments. © 2001 American Institute of Physics.
Show PACS
73.61.Ey III-V semiconductors
73.21.Cd Superlattices
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
61.72.uj III-V and II-VI semiconductors
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.20.Hb Impurity and defect levels; energy states of adsorbed species

Deep centers in a free-standing GaN layer

Z.-Q. Fang, D. C. Look, P. Visconti, D.-F. Wang, C.-Z. Lu, F. Yun, H. Morkoç, S. S. Park, and K. Y. Lee

Appl. Phys. Lett. 78, 2178 (2001); http://dx.doi.org/10.1063/1.1361273 (3 pages) | Cited 41 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Schottky barrier diodes, on both Ga and N faces of a ∼300-μm-thick free-standing GaN layer, grown by hydride vapor phase epitaxy (HVPE) on Al2O3 followed by laser separation, were studied by capacitance–voltage and deep level transient spectroscopy (DLTS) measurements. From a 1/C2 vs V analysis, the barrier heights of Ni/Au Schottky contacts were determined to be different for the two polar faces: 1.27 eV for the Ga face, and 0.75 eV for the N face. In addition to the four common DLTS traps observed previously in other epitaxial GaN including HVPE-grown GaN a new trap B′ with activation energy ET = 0.53 eV was found in the Ga-face sample. Also, trap E1 (ET = 0.18 eV), believed to be related to the N vacancy, was found in the N-face sample, and trap C (ET = 0.35 eV) was in the Ga-face sample. Trap C may have arisen from reactive-ion-etching damage. © 2001 American Institute of Physics.
Show PACS
73.20.Hb Impurity and defect levels; energy states of adsorbed species
71.55.Eq III-V semiconductors
85.30.Hi Surface barrier, boundary, and point contact devices
73.40.Ns Metal-nonmetal contacts
85.30.Kk Junction diodes
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close