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

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.

Atomic spectrometry update: review of advances in the analysis of metals, chemicals and materials

“…No signicant difference was found in the pre-and postdischarge Pb ratios meaning that any differences in Pb ratios was due to the ammunition rather than the heat and pressure of the discharge. The 206 Pb/ 204 Pb ranged from 17.36 to 20.31, 207 Pb/ 204 Pb ranged from 15.53 to 15.78 and 208 Pb/ 204 Pb ratios ranged from 37.24 to 39.19. Multivariate likelihood ratios were then calculated and led to a low rate of misleading evidence (<0.53%).…”

“…A calibration-free LIBS application for the quantification of each element in an aluminium gallium arsenide wafer was reported by Alrebdi et al 207 A Nd:YAG laser operating at either 532 nm (at 200 mJ) or 1064 nm (at 400 mJ) was used for the task. The LIBS spectra were recorded between 200 and 720 nm using a commercial instrument and the spectral lines of Al, As and Ga were used to calculate the electron number density (Stark broadened line method giving 6.5 × 10 17 cm −3 ) and the temperature (Boltzmann plot method giving 5744 ± 500 K).…”

“…304 This is because the abundance of Pb isotopes in primer components of lead styphnate varies signicantly. Forty-four samples were characterised from their isotope ratios of 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, and 208 Pb/ 204 Pb using LA-multicollector-ICP-MS.…”

LIBS assisted PCA analysis of multiple rare-earth elements (La, Ce, Nd, Sm, and Yb) in phosphorite deposits

“…2 . A detail about the experimental system is explained in our previously reported articles [ 41 , 42 ]. A Q-switched Nd: YAG, 2nd harmonic (2ω) high-power Laser (Brilliant-B Quantel, France) having 400 mJ energy at 532 nm, comprising 5 ns pulse-width, and 10 Hz frequency was employed to generate a micro-plasma on the target surface.…”

Laser Spectroscopic Characterization for the Rapid Detection of Nutrients along with CN Molecular Emission Band in Plant-Biochar

“…The calibration-free LIBS (CF-LIBS) technique has already been extensively utilized for the compositional studies of solids, liquids, and gaseous samples without using calibration standards and avoiding matrix effects, as described by Ciucci et al [ 17 ]. The standard-less CF-LIBS procedure has lots of potential uses compared to the calibration curve LIBS (CC-LIBS) for quantitative study in scientific research and industry, and for the analysis of plant biochar, coal, soil, cement, alloys, geological and biological samples [ 17 , 18 , 19 ]. For the use of the CF-LIBS technique, a few assumptions must be assured, such as stoichiometric laser-ablation, plasma should be homogeneous (spatial and temporal), optically thin, and follow the local thermodynamical equilibrium (LTE) state [ 17 ].…”