Quantitative analysis of Cu(In,Ga)Se₂thin films by secondary ion mass spectrometry using a total number counting method

Abstract

The relative atomic fraction of Cu(In,Ga)Se2 (CIGS) films is one of the most important measurements for the fabrication of CIGS thin film solar cells. However, the quantitative analysis of multi-element alloy films is difficult by surface analysis methods due to the severe matrix effect. In this study, the quantitative analysis of CIGS films was investigated by secondary ion mass spectrometry (SIMS). The atomic fractions of Cu, In, Ga and Se in the CIGS films were measured by alloy reference relative sensitivity factors derived from the certified atomic fractions of a reference CIGS film. The total ion intensities of the constituent elements were obtained by a total number counting method. The atomic fractions measured by SIMS were linearly proportional to those certified by inductively coupled plasma mass spectrometry using an isotope dilution method. The uncertainties were determined from the standard uncertainties in the measurements and those of a CIGS thin film certified reference material.

Morphological–Electrical Property Relation in Cu(In,Ga)(S,Se)2 Solar Cells: Significance of Crystal Grain Growth and Band Grading by Potassium Treatment

“…RSF is calculated by integrating the total ion intensity from the D‐SIMS profile and dividing this value by the atomic concentration, which in turn was derived from the measurements of the atomic absorption spectroscopy (AAS) and inductively coupled plasma‐optical emission spectroscopy (ICP‐OES) (Table S1, Supporting Information). [ 38 ] We found that S, Se, and K compositions are distinctly varied in AAS/ICP‐OES results. As shown in Figure S4 in the Supporting Information, the top layer of the unmodified film is enriched with Se, which shows a similar trend with the In composition distribution.…”

Toward Understanding Chalcopyrite Solar Cells via Advanced Characterization Techniques

“…As shown in Figure 4b,c, [ 33 ] atomic composition profiles are produced by dividing the D‐SIMS or AES profiles by the relative sensitivity factor (RSF). [ 66 ] The RSF is determined by integrating the total ion intensity of the profile and dividing this by the atomic concentration obtained using atomic absorption spectroscopy (AAS) and inductively coupled plasma‐optical emission spectroscopy (ICP‐OES). Ga/(Ga + In) and S/(S + Se) depth profiles are produced from the atomic concentrations and bandgap ( E g ) depth profiles are calculated from the atomic ratio using Equation () (Figure 4d) [ 62 ] where X = Ga/(Ga + In), Y = S/(S + Se), and b is the optical bowing constant for the corrections.…”

Traceable quantitative analysis of Ag x Cu1−x alloy films by ID ICP-MS, RBS and MEIS

“…Although the depth distributions of the two elements are not uniform, the relative mole fractions of Ag and Cu can be determined by comparison of total quantity (atoms cm −2 ) of each element determined by ion scattering simulations of the integrated peak intensities of Ag and Cu [23,24]. This method to determine the average mole fractions is the same methodology as the ID ICP-MS where the average mole fractions are obtained from the relative amounts of Ag and Cu dissolved in the solution.…”