TY - JOUR
T1 - Vacancies in CZ silicon crystals observed by low-temperature ultrasonic measurements
AU - Yamada-Kaneta, Hiroshi
AU - Goto, Terutaka
AU - Nemoto, Yuichi
AU - Sato, Koji
AU - Hikin, Masatoshi
AU - Saito, Yasuhiro
AU - Nakamura, Shintaro
N1 - Funding Information:
This work was supported by Grand-in-Aid for Specially Promoted Research “Strongly correlated quantum phase associated with charge fluctuation” (No. 18002008) of the Ministry of Education, Culture, Sports, Science and Technology in Japan.
PY - 2007/12/15
Y1 - 2007/12/15
N2 - By means of the low-temperature ultrasonic measurements, we try to observe the single vacancies in the as-grown Czochralski (CZ) silicon crystal of high resistivity and commercial-base quality. The crystal ingot we adopt here is grown with the pulling rate gradually lowered to produce various regions of different point-defect states. The elastic constants CT2g(T) and CEg(T) measured for the samples taken from the Pv-region exhibit the softening of the type CΓ(T)=CΓ(0) [1-ΔJT/(T-Θ)] which was found in our previous study for the non-doped FZ silicon and attributed to the neutral vacancy. The response of the softening to the applied magnetic field is found to be the same as in the case of the non-doped FZ silicon. The samples in the Pi-region exhibit no such softening, confirming that the origin of the softening is due to the vacancies. A qualitative explanation is given to the measured distribution of the vacancy concentration. For the CZ silicon crystals, the vacancies can be well observed for the Pv-region only.
AB - By means of the low-temperature ultrasonic measurements, we try to observe the single vacancies in the as-grown Czochralski (CZ) silicon crystal of high resistivity and commercial-base quality. The crystal ingot we adopt here is grown with the pulling rate gradually lowered to produce various regions of different point-defect states. The elastic constants CT2g(T) and CEg(T) measured for the samples taken from the Pv-region exhibit the softening of the type CΓ(T)=CΓ(0) [1-ΔJT/(T-Θ)] which was found in our previous study for the non-doped FZ silicon and attributed to the neutral vacancy. The response of the softening to the applied magnetic field is found to be the same as in the case of the non-doped FZ silicon. The samples in the Pi-region exhibit no such softening, confirming that the origin of the softening is due to the vacancies. A qualitative explanation is given to the measured distribution of the vacancy concentration. For the CZ silicon crystals, the vacancies can be well observed for the Pv-region only.
KW - Silicon
KW - Softening
KW - Vacancy
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U2 - 10.1016/j.physb.2007.08.131
DO - 10.1016/j.physb.2007.08.131
M3 - Article
AN - SCOPUS:36049040324
SN - 0921-4526
VL - 401-402
SP - 138
EP - 143
JO - Physica B: Condensed Matter
JF - Physica B: Condensed Matter
ER -