GB/T 40110-2021 in English

Principle of the method

Total reflection X-ray fluorescence spectrometry (TXRF) excites characteristic X-rays of elements on the sample surface at an extremely low grazing angle (0.5°-8.7mrad), and uses the total reflection effect to control the detection depth within 5nm, significantly improving the surface sensitivity. The standard covers the element range of S(16)-U(92) with a detection limit of 1×1010atoms/cm2.

Special requirements for VPD-TXRF method

Vapor phase decomposition collection should be carried out in an ISO4 clean environment, using ultrapure HF reagent. The diameter of the residue should be controlled within 350μm, and the deposition of environmental pollutants should be avoided during the drying process. This method can reduce the detection limit to 5×10⁸atoms/cm².

Reference material selection

Ni/Fe reference materials prepared by SC1 impregnation method are preferred, with a surface density of 10¹²-10¹³atoms/cm². The angle scanning curve morphology needs to be verified regularly, and the storage validity period shall not exceed 6 months.

Relative sensitivity factor calculation model

The formula used is: S_R = (γ_A-1/γ_A)·(ω_Ag_LA_r,AE_A)/(μ/ρ)_A,λp, and the S_R of Ni during W-Lα excitation is set to 1.000.