An Investigation of Quanfifative Energy-Dispersive x-ray Analysis of Thin Foils

The accuracy of quantitative analysis of thin foils in The energy dispersive x-ray spectrometer, EDAX9100, has been measured with samples of known composition.The results indicate that at 100KV, a relative error of 5-10% Can be achived using The EDAX9100 program when K-K or L-L x-ray Lines of elements with close atomic number are being analyzed. The relative error becomes progressively worse,up to abont 20% to 50% if The difference in atomic number between The two analyzed elements increaces, and the different x-ray lines are analgzed.
The absorption of thin film specimens has been studied The results indicate that x-ray absorption within the sample must be Considered when there is a significant difference in The energy of The Characteristic x-raysAt lower voltages a correction must be applied to the K factor in the EDAX9100 program. The EDAX9100 program must be Corrected for using iines from different x-rag shells.Reasonable equations for calculating the lonization cross section and fluorescence yields have been Chosen, and the ratio of coefficients of K, L and M shell lines have been calculated to be q_K:b_L:b_M=0.35:0.35:0.24.
The relative error after correcting the program for absorption,voltage,and different x-ray shells, is less than 10% for all x-ray lines analyged.