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Defects in Semiconductors 


Important Results:

  1. Bond Center Hydrogen
  2. H/D Isotope Effect
  3. Structure Dependent Lifetimes
  4. Hydrogen Bending Modes
  5. Interstitial Oxygen in Si and Ge

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>> Hydrogen Bending Modes

Vibrational lifetimes of hydrogen and deuterium related bending modes in semiconductors are measured by transient bleaching spectroscopy and high-resolution infrared absorption spectroscopy. The vibrational lifetime T1 = 12.2  ± 0.8 ps for the bending mode of H2* in Si.

We find that the vibrational lifetimes follow a universal  frequency-gap law, i.e., the decay time increases exponentially with increasing decay order, with values ranging from 1 ps for a one-phonon process to 265 ps for a four-phonon process. The temperature dependence of the lifetime shows that the bending mode decays by lowest-order multi-phonon process. Our results provide new insights into vibrational decay and the giant isotope effect of hydrogen in semiconductor systems.

 

Reference:

  1. B. Sun, G. A. Shi, S. V. S. Nageswara Rao, M. Stavola, N. H. Tolk, S. K. Dixit, L. C. Feldman, G. Lüpke, Vibrational Lifetimes and Frequency-Gap Law of Hydrogen Bending Modes in Semiconductors, Phys. Rev. Lett. 96, 2006, pp. 035501-4.

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>> Next :: Interstitial Oxygen in Si and Ge ::

Funding: NSF, DoE, Jeffress Foundation


 


 


 

 
 
         
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