Suppression of interdiffusion in InGaAs/GaAs quantum dots using dielectric layer of titanium dioxide

Fu, L.; Lever, P.; Tan, H. H.; Jagadish, C.; Reece, P.; Gal, M.
April 2003
Applied Physics Letters;4/21/2003, Vol. 82 Issue 16, p2613
Academic Journal
In this work, titanium dioxide (TiO[SUB2]) film was deposited onto the In[SUB0.5]Ga[SUB0.5]As/GaAs quantum-dot structure by electron-beam evaporation to investigate its effect on interdiffusion. A large redshifted and broadened spectrum from the dot emission was observed compared with that from the uncapped (but annealed) reference sample, indicating the suppression of thermal interdiffusion due to TiO[SUB2] deposition. The structure was also capped with a silicon dioxide SiO[SUB2] single layer or SiO[SUB2]/TiO[SUB2] bilayer with the thickness of SiO[SUB2] varied from ∼6 to ∼145 nm. In the former case, an increased amount of impurity-free vacancy disordering (IFVD) was introduced with the increase of SiO[SUB2] thickness due to the enhanced Ga outdiffusion into the film. With TiO[SUB2] deposited on top, IFVD and thermal interdiffusion were suppressed to different extents with the variation of SiO[SUB2] thickness. To explain the suppression of interdiffusion, thermal stress introduced by the large thermal expansion coefficient of TiO[SUB2] (when compared with GaAs) as well as the metallurgical reactions between the TiO[SUB2] and GaAs were proposed as possible mechanisms.


Related Articles

  • Preparation and properties of rare earth-doped TiO2 thin films by sol-gel process. Tao Bai; Shigen Zhu // Advanced Materials Research;2014, Issue 1033-1036, p1235 

    Rare earth doped titaniumdioxide (TiO2) thin films (rare earth-doped TiO2) have been successfully prepared on a glass substrate by a sol-gel route. After the rare earth-doped TiO2 thin films were calcined at 773K for 1h, the effect of rare earth-doping on the properties were investigated using...

  • Erratum to "Effect of Au Nanoparticles Doping on The Properties of TiO2 Thin Films". GÜLTEKİN, Aytaç // Materials Science / Medziagotyra;2014, Vol. 20 Issue 3, p371 

    A correction to the article "Effect of Au Nanoparticles Doping on The Properties of TiO2 Thin Films" that was published in a 2014 issue is presented.

  • Substrate bias dependence of Raman spectra for TiN films deposited by filtered cathodic vacuum arc. Cheng, Y. H.; Tay, B. K.; Lau, S. P.; Kupfer, H.; Richter, F. // Journal of Applied Physics;8/15/2002, Vol. 92 Issue 4, p1845 

    Raman spectroscopy was used to characterize TiN films deposited by using an off-plane double bend filtered cathodic vacuum arc technique. The influence of substrate bias on the Raman spectra was systematically studied. Four peaks at 235, 320, 440, and 570 cm[sup -1], related to transverse...

  • Infrared response of vitreous titanium dioxide films with anatase short-range order. Scarel, G.; Hirschmugl, C. J.; Yakovlev, V. V.; Sorbello, R. S.; Aita, C. R.; Tanaka, H.; Hisano, K. // Journal of Applied Physics;2/1/2002, Vol. 91 Issue 3, p1118 

    The polarization-dependent optical response of vitreous titanium dioxide films was determined by infrared reflection–absorption spectroscopy (IRAS). The predominant nearest-neighbor coordination (short-range order) in the films was characteristic of crystalline anatase. A dielectric...

  • Transparent films of titanium dioxide on solids. Yadav, G.D. // Chemical Business;Jul97, Vol. 10 Issue 12, p26 

    Discusses the coating application of titanium dioxide in solids like non-alkali glass, alumina and stainless steel.

  • Riddle of the red shift. Gribbin, John // New Scientist;7/9/94, Vol. 143 Issue 1933, p17 

    Reports on the discovery showing that there is a pattern in the red shifts of nearly a hundred galaxies out to a distance of about 50 megaparsecs from Milky Way galaxy. Description of the red shift; Causes of red shifts; Studies on red shifts as a distance indicator.

  • Redshift records renewed.  // Sky & Telescope;Jan97, Vol. 93 Issue 1, p12 

    Reports on two redshift records furthering progress in the cosmological quest to decipher the universe's history. Enigmatic object studied with a redshift of 4.41; Captured exploding stars in 17 galaxies with the Blanco 4-meter reflector; Possibility for astronomers to gauge the rate at which...

  • A stellar relic from the early Milky Way. Christlieb, N.; Bessell, M. S.; Beers, T. C.; Gustafsson, B.; Korn, A.; Barklem, P. S.; Karlsson, T.; Mizuno–Wiedner, M.; Rossi, S. // Nature;10/31/2002, Vol. 419 Issue 6910, p904 

    The chemical composition of the most metal-deficient stars largely reflects the composition of the gas from which they formed. These old stars provide crucial dues to the star formation history and the synthesis of chemical elements in the early Universe. They are the local relics of epochs...

  • Galaxy redshift record broken anew.  // Sky & Telescope;Jun98, Vol. 95 Issue 6, p16 

    Focuses on the measurement of the farthest astronomical distances of galaxy redshifts by researchers from John Hopkins University and the University of Hawaii. Computation of the distance; Spectrograph observations.


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics