[17p-B2-1~9] 15.7 Crystal characterization, impurities and crystal defects

3:00 PM - 3:15 PM JST(6:00 AM - 6:15 AM UTC)

[17p-B2-8] High sensitivity infrared absorption spectroscopy and infrared defect dynamics of silicon crystal/
2-nd generation (25) Single interstitial nitrogen, Ni

〇Naohisa Inoue¹, Shuichi Kawamata¹, Shuichi Okuda¹ (1.Osaka Metropolitan Univ. Radiation Research center)

Keywords:

silicon crystal,nitrogen,infrared absorption

Nitrogen in Si has been thought to mainly form NiNi pair (Si-N-Si-N rectangle), and N concentration was measured by its infrared absorption. We found high amount of Ni both in CZ and FZ as-grown Si By annealing, it forms NiOi chain in CZ Si whereas it forms VNs in FZ Si. This suggests the V-rich character of the samples. Recently, it has been reported that the deep level in annealed NFZ Si degrade the lifetime of power device. We attributed it, to VNs from Ni. Therefore, we examined Ni in old CZ crystals around 2000. Ni absorption bands are also observed. O2i 1062 cm-1 absorption is strong in the old crystals, suggesting their I-rich character. In summary, it is important to measure Ni concentration in as-grown Si, and V/I-rich character by O2i absorption.