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An imperfections or defects may appear in fabricated monocrystalline solar cells. These microstructural imperfections
could have impact on the parameters of whole solar cell. The research is divided into two parts, firstly, the detection and
localization defects by using several techniques including current-voltage measurement, scanning probe microscopy
(SPM), scanning electron microscope (SEM) and electroluminescence. Secondly, the defects isolation by a focused ion
beam (FIB) milling and impact of a milling process on solar cells. The defect detection is realized by I-V measurement
under reverse biased sample. For purpose of localization, advantage of the fact that defects or imperfections in silicon solar
cells emit the visible and near infrared electroluminescence under reverse biased voltage is taken, and CCD camera measurement
for macroscopic localization of these spots is applied. After rough macroscopic localization, microscopic localization
by scanning probe microscopy combined with a photomultiplier (shadow mapping) is performed. Defect isolation
is performed by a SEM equipped with the FIB instrument. FIB uses a beam of gallium ions which modifies crystal structure
of a material and may affect parameters of solar cell. As a result, it is interesting that current in reverse biased sample with
isolated defect is smaller approximately by 2 orders than current before isolation process.
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