Detection and Localization of Defects in Monocrystalline Silicon Solar Cell

Abstract

Near-surface defects in solar cell wafer have undesirable influence upon device properties, as its efficiency and lifetime. When reverse-bias voltage is applied to the wafer, a magnitude of electric signals from defects can be measured electronically, but the localization of defects is difficult using classical optical far-field methods. Therefore, the paper introduces a novel combination of electric and optical methods showing promise of being useful in detection and localization of defects with resolution of 250 nm using near-field nondestructive characterization techniques. The results of mapped topography, local surface reflection, and local light to electric energy conversion measurement in areas with small defects strongly support the development and further evaluation of the technique.

Local characterization of light trapping effects of metallic and dielectric nanoparticles in ultra-thin Cu(In,Ga)Se2 solar cells via scanning near-field optical microscopy

“…A spectrometer or charge-coupled device (CCD) camera can be used to obtain the near-field optical signal as reflection or transmission or photoenergy spectrum [12]. By combining the SNOM with a photocurrent detector, one can analyze the generation of charge carriers due to the localized light illumination [14].…”

“…The interaction between nanoparticles and light can be investigated within sub-wavelength resolution by local illumination. The flexibility of the SNOM system guarantees the combination with various techniques and its application in different characterization such as biological [13], opto-electrics [14] and opto-magnetics [15] research. In this paper, we used SNOM not only for optics study but also for photocurrent measurement.…”

Microscopic optoelectronic defectoscopy of solar cells

“…Monocrystalline silicon, due to its structure, is very interesting material for local investigation and comparison of used methods as SEM visualization of defects, electric noise measurement and local topography and near-field optical beam induced current measurements [7][8][9][10].…”

DPiT: Detecting Defects of Photovoltaic Solar Cells With Image Transformers

“…Previous works mainly tend to detect defects of solar cells by physical methods. The work [1] introduces current-voltage (IV) characteristics for silicon cell characterization. Besides, thermography which is only implemented on infrared ray images is adopted for defects detection [2]- [4].…”