Quantification of Aluminum Gallium Arsenide (AlGaAs) Wafer Plasma Using Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS)

Tahani A Alrebdi; Amir Fayyaz; Haroon Asghar; Asif Zaman; Mamoon Asghar; Fatemah H Alkallas; Atif Hussain; Javed Iqbal; Wilayat Khan

doi:10.3390/molecules27123754

Quantification of Aluminum Gallium Arsenide (AlGaAs) Wafer Plasma Using Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS)

Molecules. 2022 Jun 10;27(12):3754. doi: 10.3390/molecules27123754.

Authors

Tahani A Alrebdi¹, Amir Fayyaz², Haroon Asghar², Asif Zaman³, Mamoon Asghar⁴, Fatemah H Alkallas¹, Atif Hussain⁵, Javed Iqbal⁶, Wilayat Khan⁷

Affiliations

¹ Department of Physics, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia.
² National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320, Pakistan.
³ Department of Physics, Islamia College, Peshawar 25000, Pakistan.
⁴ Department of Physics, University of Gujrat, Hafiz Hayat Campus, Gujrat 50700, Pakistan.
⁵ Department of Physics, The University of Lahore, Gujrat Campus, Gujrat 50700, Pakistan.
⁶ Department of Physics, Azad Jammu and Kashmir University, Muzaffarabad 13100, Pakistan.
⁷ Department of Physics, Bacha Khan University, Charsadda 24420, Pakistan.

Abstract

In this work, we report the results of the compositional analysis of an aluminum gallium arsenide (AlGaAs) sample using the calibration-free laser-induced breakdown spectroscopy (CF-LIBS) technique. The AlGaAs sample was doped with three various concentrations of gallium (Ga), arsenic (As), and aluminum (Al), as reported by the manufacturer, and the CF-LIBS technique was employed to identify the doping concentration. A pulsed Q-switched Nd: YAG laser capable of delivering 200 and 400 mJ energy at 532 and 1064 nm, respectively, was focused on the target sample for ablation, and the resulting emission spectra were captured using a LIBS 2000+ spectrometer covering the spectral range from 200 to 720 nm. The emission spectra of the AlGaAs sample yielded spectral lines of Ga, As, and Al. These lines were further used to calculate the plasma parameters, including electron temperature and electron number density. The Boltzmann plot method was used to calculate the electron temperature, and the average electron temperature was found to be 5744 ± 500 K. Furthermore, the electron number density was calculated from the Stark-broadened line profile method, and the average number density was calculated to be 6.5 × 10¹⁷ cm^-3. It is further observed that the plasma parameters including electron temperature and electron number density have an increasing trend with laser irradiance and a decreasing trend along the plume length up to 2 mm. Finally, the elemental concentrations in terms of weight percentage using the CF-LIBS method were calculated to be Ga: 94%, Al: 4.77% and As: 1.23% for sample-1; Ga: 95.63%, Al: 1.15% and As: 3.22% for sample-2; and Ga: 97.32%, Al: 0.69% and As: 1.99% for sample-3. The certified concentrations were Ga: 95%, Al: 3% and As: 2% for sample-1; Ga: 96.05%, Al: 1% and As: 2.95% for sample-2; and Ga: 97.32%, Al: 0.69% and As: 1.99% for sample-3. The concentrations measured by CF-LIBS showed good agreement with the certified values reported by the manufacturer. These findings suggest that the CF-LIBS technique opens up an avenue for the industrial application of LIBS, where quantitative/qualitative analysis of the material is highly desirable.

Keywords: AlGaAs; CF-LIBS; compositional analysis; plasma parameters; quantitative analysis.

Grants and funding

Princess Nourah bint Abdulrahman University Researchers Supporting Project number (PNURSP2022R71), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia.