Laser‐induced breakdown spectroscopy for photovoltaic silicon wafer analysis

Abstract

The principal subject matter of this work is the application of laser‐induced breakdown spectroscopy for the multi‐elemental analytical characterization of different qualities of solid silicon. The physical process upon which the technique is based is the temporally resolved observation of emission spectra emitted by a micro‐plasma generated by a laser focused on the surface of a given sample. The optimal environmental parameters such as the composition of the buffering gas for the identification and measurement of several metallic, non‐metallic, and dopant impurities were determined. Particular attention was given to boron. A detection limit of 2.10−4 mg/g of boron was found using a calibration curve, which was made in the range of 1 to 100 ppmw. Silicon samples from different production techniques (4C and directional solidification), which permit the segregation of different impurities along the length of the silicon ingot were analyzed using laser‐induced breakdown spectroscopy. Copyright © 2011 John Wiley & Sons, Ltd.

Manufacturing metrology for c-Si photovoltaic module reliability and durability, Part I: Feedstock, crystallization and wafering

“…Using photoluminescence is certainly attractive [158]. An alternative would be laser-induced breakdown spectroscopy for the multi-elemental analytical characterization of silicon samples; it is non-destructive, fast, highly sensitive to multiple elements, and does not require any sample preparation [48].…”

“…As a result, not every chunk, granule, or fines can be tested. A fast and accurate method, such as laserinduced breakdown spectroscopy (LIBS) could be useful [48].…”

“…Table 9 summarizes useful wafer manufacturing metrology techniques for increased module reliability. Metal Impurities X-ray fluorescence spectroscopy (XRF) Energy Dispersive X-Ray Spectroscopy (EDX) [113] Cathodoluminescence (CL) Laser-induced breakdown spectroscopy (LIBS) [48] Photoluminescence (PL) [158,159] Vapor phase decomposition droplet collection (VPD-DC) [181] Total reflection X-ray fluorescence spectroscopy (TXRF) [181] Modified inductively coupled plasma mass spectrometry (ICP-MS) [181] Liquid surface etching (LSE) followed by TXRF […”

Laser-Induced Breakdown Spectroscopy Imaging for Material and Biomedical Applications: Recent Advances and Future Perspectives

“…The most common calibration method uses reference materials with known concentrations and compositions similar to those of the sample of interest to be analyzed under similar conditions to build calibration models. For example, the quantitative imaging of steel, boron-doped crystalline silicon, glass, , and biological and other materials − has already been reported. When reference materials are unavailable, one possibility is to regard the imaging data set as representative of the entire sample volume.…”

Improving Spatial Resolution by Reinterpreting Dosage for Laser-Induced Breakdown Spectroscopy Imaging: Conceptualization and Limitations

“…7 Furthermore, LIBS was employed in the semiconductor industry to assess different metallic and nonmetallic impurities as well as dopants. 8 In material science, LIBS can also be utilized to examine elemental distributions; especially for catalytic particles this can provide valuable insights into the catalytic activity, which was demonstrated by Trichard et al 9 Signal generation in LIBS relies on the formation of a plasma on the sample by irradiation with a laser. A highly energetic laser pulse causes excitation of the sample and creates a highly ionized plasma consisting of cations and electrons, which emits discrete spectral lines as well as bands and continuum as a result of recombination and deexcitation processes.…”