Evidence for negatively charged vacancy defects in 6H-SiC after low-energy proton implantation

Britton, D. T.; Barthe, M.-F.; Corbel, C.; Hempel, A.; Henry, L.; Desgardin, P.; Bauer-Kugelmann, W.; Ko¨gel, G.; Sperr, P.; Triftsha¨user, W.
February 2001
Applied Physics Letters;2/26/2001, Vol. 78 Issue 9, p1234
Academic Journal
We have used pulsed-slow-positron-beam-based positron lifetime spectroscopy to investigate the nature of acceptors and charge states of vacancy-type defects in low-energy proton-implanted 6H-SiC(H). We can infer from the temperature dependence of the lifetime spectra that neutral and negatively charged vacancy clusters exist in the track region. Depending on annealing, they give rise to positron lifetimes of 257±2, 281±4, and 345±2 ps, respectively. The 281 ps cluster likely has an ionization level near the middle of the band gap. By comparison with theory, the 257 and 280 ps are identified as (V[sub C]-V[sub Si])[sub 2] and (V[sub C]-V[sub Si])[sub 3] clusters, respectively. In addition, other acceptors of ionic type act as strong trapping centers at low temperature (T<150 K). Neutral monovacancy-like complexes are also detected with a lifetime of 160±2 after 900 °C annealing. © 2001 American Institute of Physics.


Related Articles

  • TGRS measurements of the positron annihilation spectrum from the galactic center. Harris, M. J.; Teegarden, B. J.; Cline, T. L.; Gehrels, N.; Palmer, D. M.; Ramaty, R.; Seifert, H. // AIP Conference Proceedings;2000, Vol. 510 Issue 1, p31 

    The TGRS experiment on board the Wind spacecraft includes a Ge detector with very high resolution (3–4 keV FWHM) at energies around 511 keV. To take advantage of WIND’s fixed pointing at the south ecliptic pole and its 3 s rotation, TGRS also includes a Pb occulter fixed on the...

  • Investigations of positron annihilation radiation. Milne, P. A.; Kurfess, J. D.; Kinzer, R. L.; Leising, M. D.; Dixon, D. D. // AIP Conference Proceedings;2000, Vol. 510 Issue 1, p21 

    By combining OSSE, SMM and TGRS observations of the galactic center region, Purcell et al. (1997) and Cheng et al. (1997) produced the first maps of galactic positron annihilation. That data-set has been augmented with additional data, both recent and archival, and re-analyzed to improve the...

  • Positronium formation in SiO2 films grown on Si substrates studied by monoenergetic positron beams. Uedono, A.; Wei, L.; Tanigawa, S.; Suzuki, R.; Ohgaki, H.; Mikado, T.; Kawano, T.; Ohji, Y. // Journal of Applied Physics;4/15/1994, Vol. 75 Issue 8, p3822 

    Focuses on a study which investigated the annihilation characteristics of positrons in silicate films grown in silicon substrates using monoenergetic positron beams. Measurement of Doppler broadening profiles of the annihilation radiation and lifetime spectra of positrons; Discussion on...

  • Study of DX center in Cd0.8Zn0.2Te:Cl by positron annihilation. Fung, S.; Shan, Y.Y.; Deng, A.H.; Ling, C.C.; Beling, C.D.; Lynn, K.G. // Journal of Applied Physics;8/15/1998, Vol. 84 Issue 4, p1889 

    Presents information pertaining to the study of the DX center in cadmium (Cd)0.8 zinc (Zn)0.2 tellurium (Te):chlorine (Cl) at 50 K, using positron beam and positron annihilation experiments. Details on how the Cd0.8Zn0.2Te crystal was grown; Method used to conduct positron diffusion and trapping...

  • Probing capped and uncapped mesoporous low-dielectric constant films using positron annihilation lifetime spectroscopy. Petkov, Mihail P.; Weber, Marc H.; Lynn, Kelvin G.; Rodbell, Kenneth P. // Applied Physics Letters;10/16/2000, Vol. 77 Issue 16 

    We have measured uncapped mesoporous low-dielectric-constant films using positron annihilation lifetime spectroscopy (PALS), a nondestructive technique, which yields both pore-size distributions and the threshold for pore interconnectivity. Pairs of fully cured capped and uncapped identical...

  • Positron annihilation in solid, liquid and undercooled melts of Co[sub 80] Pd[sub 20]. B�hrer, C.; Holzwarth, U.; Maier, K.; Platzek, D.; Reske, J. // Applied Physics A: Materials Science & Processing;1996, Vol. 63 Issue 2, p191 

    Positron annihilation measurements have been performed in solid, liquid and undercooled Co[sub 800oPd[sub 20] alloy using electromagnetic levitation as containerless processing method. The formation enthalpy for a single vacancy is H[sub 1v] = (1.7 � 0.1) eV. In the melt, the thermal...

  • Effect of iodine sorption on the free volume of polycarbonate. Ramani, R.; Raganathaiah, C. // Applied Physics A: Materials Science & Processing;1997, Vol. 64 Issue 2, p161 

    The effect of iodine sorption on the free volume of polycarbonate is investigated by Positron Annihilation Lifetime method. The observed results are interpreted in terms of the Charge Transfer Complex formation and precipitation of iodine at the initial and final stages of sorption,...

  • A simple positron lifetime spectrometer for a magnetically guided low-energy beam. Szpala, Stanislaw; Petkov, Mihail P.; Lynn, Kelvin G. // Review of Scientific Instruments;Jan2002, Vol. 73 Issue 1, p147 

    We present a new, simple, and inexpensive positron lifetime spectrometer intended for the depth-resolved characterization of thin films and buried interfaces. The spectrometer operates on a conventional magnetically guided positron beam with energies ranging from 1 to ∼50 keV. Given is a...

  • Detection of hydrogen-plasma-induced defects in Si by positron annihilation. Asoka-Kumar, P.; Stein, H.J. // Applied Physics Letters;3/28/1994, Vol. 64 Issue 13, p1684 

    Evaluates hydrogen-plasma-induced defects in silicon semiconductors by positron annihilation. Presence of voidlike structures in a defective layer; Correlation between the Doppler broadening parameter for the gamma rays and hydrogen coverage of the void surfaces; Release of hydrogen from the voids.


Read the Article


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

Try another library?
Sign out of this library

Other Topics