https://doi.org/10.1051/epjap:2004104
Photoluminescence and X-ray topography measurements on oxidation-induced stacking faults in silicon wafers
1
Department of Electronics and Information Science, Kyoto Institute of
Technology, Matsugasaki, Sakyo-ku Kyoto 606-8585, Japan
2
Crystal Technology Dept., Komatsu Electronic Metals Co., Ltd,
1324-2, Masuragahara, Omura, Nagasaki 856-8555, Japan
Corresponding author: yamada@dj.kit.ac.jp
Received:
30
July
2003
Accepted:
13
February
2004
Published online: 15 July 2004
In order to investigate oxidation-induced stacking faults (OSF), Cu-decorated Si wafers have been examined by dark-field optical microscope (OM), transmission X-ray topography (XRT), and scanning photoluminescence (sPL). It is found from OM observation that there are bright pits with several 10 µm sizes, forming a single ring, although there are many fine pits. On the other hand, a few subsidiary rings, in addition to the main OM ring, are observed by XRT and sPL measurements, although they do not directly correlate each other. It is found from microscopic PL measurement that there are dark spots, corresponding to the bright OM pits in the main OSF ring. By comparing the OM and sPL results, it is clearly found that the dark PL spots are corresponding not to fine OM pits but large OM pits with several 10 µm sizes, which seem to be due to copper oxides or precipitates on the surface. It may be emphasized that the sPL technique presented here may be used instead of OM to observe the OSF ring in Cu-decorated Si wafers, and also instead of XRT to observe the OSF ring in standard Si wafers annealed without copper decoration, because PL is more sensitive than OM observation and its intensity is related to the lifetime and concentration of carriers.
PACS: 61.72.Ff – Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.) / 61.72.Nn – Stacking faults and other planar or extended defects / 78.55.Ap – Elemental semiconductors
© EDP Sciences, 2004
