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Title: Impact of nitridation on open volumes in HfSiO{sub x} studied using monoenergetic positron beams

Abstract

The effects of nitridation on open volumes in thin HfSiO{sub x} films fabricated by metal-organic chemical vapor deposition were studied using monoenergetic positron beams. It was found that positrons were annihilated from the trapped state by open volumes that exist intrinsically in amorphous HfSiO{sub x} structures. In an as-deposited film, the positrons were annihilated from two different types of open volume. After plasma nitridation, the probability of positrons trapped by larger open volumes decreased, which is attributed to nitride trapped by such regions. The mean size of the open volumes increased after annealing, suggesting expansion of the open volumes due to the incorporation of nitride into the HfSiO{sub x} matrix.

Authors:
; ; ; ; ; ; ; ; ; ;  [1];  [2];  [2];  [2]
  1. Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
20779176
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 88; Journal Issue: 17; Other Information: DOI: 10.1063/1.2200399; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; ANNIHILATION; CHEMICAL VAPOR DEPOSITION; DIELECTRIC MATERIALS; EXPANSION; HAFNIUM SILICATES; NITRIDATION; NITRIDES; ORGANOMETALLIC COMPOUNDS; PHYSICAL RADIATION EFFECTS; PLASMA; POSITRON BEAMS; PROBABILITY; THIN FILMS; TRAPPING

Citation Formats

Uedono, A., Ikeuchi, K., Otsuka, T., Yamabe, K., Eguchi, K., Takayanagi, M., Ohdaira, T., Muramatsu, M., Suzuki, R., Hamid, A.S., Chikyow, T., Semiconductor Technology Academic Research Center, 17-2, Shin Yokohama 3-chome, Kohoku, Yokohama 222-0033, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, and Nanomaterials Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003. Impact of nitridation on open volumes in HfSiO{sub x} studied using monoenergetic positron beams. United States: N. p., 2006. Web. doi:10.1063/1.2200399.
Uedono, A., Ikeuchi, K., Otsuka, T., Yamabe, K., Eguchi, K., Takayanagi, M., Ohdaira, T., Muramatsu, M., Suzuki, R., Hamid, A.S., Chikyow, T., Semiconductor Technology Academic Research Center, 17-2, Shin Yokohama 3-chome, Kohoku, Yokohama 222-0033, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, & Nanomaterials Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003. Impact of nitridation on open volumes in HfSiO{sub x} studied using monoenergetic positron beams. United States. doi:10.1063/1.2200399.
Uedono, A., Ikeuchi, K., Otsuka, T., Yamabe, K., Eguchi, K., Takayanagi, M., Ohdaira, T., Muramatsu, M., Suzuki, R., Hamid, A.S., Chikyow, T., Semiconductor Technology Academic Research Center, 17-2, Shin Yokohama 3-chome, Kohoku, Yokohama 222-0033, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, and Nanomaterials Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003. Mon . "Impact of nitridation on open volumes in HfSiO{sub x} studied using monoenergetic positron beams". United States. doi:10.1063/1.2200399.
@article{osti_20779176,
title = {Impact of nitridation on open volumes in HfSiO{sub x} studied using monoenergetic positron beams},
author = {Uedono, A. and Ikeuchi, K. and Otsuka, T. and Yamabe, K. and Eguchi, K. and Takayanagi, M. and Ohdaira, T. and Muramatsu, M. and Suzuki, R. and Hamid, A.S. and Chikyow, T. and Semiconductor Technology Academic Research Center, 17-2, Shin Yokohama 3-chome, Kohoku, Yokohama 222-0033 and National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 and Nanomaterials Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003},
abstractNote = {The effects of nitridation on open volumes in thin HfSiO{sub x} films fabricated by metal-organic chemical vapor deposition were studied using monoenergetic positron beams. It was found that positrons were annihilated from the trapped state by open volumes that exist intrinsically in amorphous HfSiO{sub x} structures. In an as-deposited film, the positrons were annihilated from two different types of open volume. After plasma nitridation, the probability of positrons trapped by larger open volumes decreased, which is attributed to nitride trapped by such regions. The mean size of the open volumes increased after annealing, suggesting expansion of the open volumes due to the incorporation of nitride into the HfSiO{sub x} matrix.},
doi = {10.1063/1.2200399},
journal = {Applied Physics Letters},
number = 17,
volume = 88,
place = {United States},
year = {Mon Apr 24 00:00:00 EDT 2006},
month = {Mon Apr 24 00:00:00 EDT 2006}
}
  • Thin Hf{sub 0.6}Si{sub 0.4}O{sub x} and Hf{sub 0.3}Al{sub 0.7}O{sub x} films fabricated by metal-organic chemical-vapor deposition and atomic-layer-deposition techniques were characterized using monoenergetic positron beams. Measurements of the Doppler broadening spectra of annihilation radiation and the lifetime spectra of positions indicated that positrons annihilated from the trapped state by open volumes that exist intrinsically in amorphous structures of the films. For HfSiO{sub x}, the mean size of the open volumes and their size distribution decreased with increasing postdeposition annealing (PDA) temperature. For HfAlO{sub x}, although the overall behavior of the open volumes in response to annealing was similar to thatmore » for HfSiO{sub x}, PDA caused a separation of the mean size of the open volumes. When this separation occurred, the value of the line-shape parameter S increased, suggesting an oxygen deficiency in the amorphous matrix. This fragmentation of the amorphous matrix can be suppressed by decreasing the annealing time.« less
  • The effect of annealing on open volumes in strained SiN films deposited on Si by plasma enhanced chemical vapor deposition was studied using monoenergetic positron beams. For compressive SiN, the stress was reduced by postdeposition annealing; this effect was attributed to the relaxation of matrix structures accompanied by an expansion of small open spaces intrinsically existing in the matrix and the introduction of large open volumes. For tensile SiN, although annealing tends to decrease the concentration of large open volumes, the size of the small open spaces and the film stress were almost constant up to 1000 deg. C annealing.more » This was attributed to the network structure related to the open spaces remaining stable even at 1000 deg. C annealing, and this mainly determines the stress in the tensile film.« less
  • Native defects in In{sub x}Ga{sub 1−x}N layers grown by metalorganic chemical vapor deposition were studied using monoenergetic positron beams. Measurements of Doppler broadening spectra of the annihilation radiation and lifetime spectra of positrons for a 200-nm-thick In{sub 0.13}Ga{sub 0.87}N layer showed that vacancy-type defects were introduced by InN alloying, and the major species of such defects was identified as complexes between a cation vacancy and nitrogen vacancies. The presence of the defects correlated with lattice relaxation of the In{sub 0.13}Ga{sub 0.87}N layer and the increase in photon emissions from donor-acceptor-pair recombination. The species of native defects in In{sub 0.06}Ga{sub 0.94}Nmore » layers was the same but its concentration was decreased by decreasing the InN composition. With the layer thickness increased from 120 nm to 360 nm, a defect-rich region was introduced in the subsurface region (<160 nm), which can be associated with layer growth with the relaxation of compressive stress.« less
  • The annealing behaviors of oxygen vacancies introduced by the epitaxial growth of thin SrTiO{sub 3} and Al{sub 2}O{sub 3} films on SrTiO{sub 3} substrates were studied by using a monoenergetic positron beam. The films were grown by molecular-beam epitaxy without using an oxidant. The Doppler broadening spectra of the annihilation radiation were measured as a function of the incident positron energy for samples fabricated under various growth conditions. The line-shape parameter S, corresponding to the annihilation of positrons in the substrate, was increased by the film growth, suggesting diffusion of oxygen from the substrate into the film and a resultantmore » introduction of vacancies (mainly oxygen vacancies). A clear correlation between the value of S and the substrate conductivity was obtained. From isochronal annealing experiments, the Al{sub 2}O{sub 3} thin film was found to suppress the penetration of oxygen from the atmosphere for annealing temperatures below 600 deg. C. Degradation of the film's oxygen blocking property occurred due to the annealing at 700 deg. C, and this was attributed to the oxidation of the Al{sub 2}O{sub 3} by the atmosphere and the resultant introduction of vacancy-type defects.« less
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