IR-LTS a powerful non-invasive tool to observe crystal defects in as-grown silicon, after device processing, and in heteroepitaxial layers

Conference · Sun Dec 01 04:00:00 EST 1996

OSTI ID:405509

Kissinger, G; Richter, H ^[1]; Vanhellemont, J; Claeys, C ^[2]

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1. Institute of Semiconductor Physics, Frankfurt (Germany)
2. IMEC, Leuven (Belgium); and others

One of the main advantages of infrared light scattering tomography (IR-LST) is the wide range of defect densities that can be studied using this technique. As-grown defects of low density and very small size as well as oxygen precipitation related defects that appear in densities up to some 1010 cm{sup -3} can be observed. As-grown wafers with a {open_quotes}stacking fault ring{close_quotes} were investigated in order to correlate the defects observed by IR-LST with the results of Secco etching and alcaline cleaning solution (SC1) treatment revealing flow pattern defects (FPDs) and crystal originated particles (COPs), respectively. These wafers were studied after a wet oxidation at 1100{degrees}C for 100 min. In processed CZ silicon wafers it was possible to identify stacking faults and prismatic punching systems directly from the IR-LST image. Brewster angle illumination is a special mode to reveal defects in epitaxial layers in a non-destructive way. Misfit dislocations in the interface between a Ge{sub 0.92}Si{sub 0.08} layer and a silicon substrate were studied using this mode that allows to observe very low dislocation densities.

• OSTI ID: 405509
• Report Number(s): CONF-951231--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL DEFECTS
DISLOCATIONS
ETCHING
GERMANIUM SILICIDES
LAYERS
LIGHT SCATTERING
SEMICONDUCTOR DEVICES
SILICON
STACKING FAULTS