Total Reflection X-ray Fluorescence (TXRF)

Total Reflection X-rays Fluorescence (TXRF) utilizes total reflection of incident primary X-Rays, to enhance the intensity of Secondary (Fluorescent) X-rays emitted from a thin sample, placed on a polished carrier. This enables trace and ultra-trace elemental surface analysis of thin sample layers.

Total Reflection X-ray Fluorescence (TXRF)

Total Reflection X-rays Fluorescence (TXRF) utilizes total reflection of a known wavelength of primary X-Rays, to reduce background scatter and noise in the secondary emission (Fluorescence) from a targeted sample surface. This technique increases the intensity of the desired spectrum of Secondary X-Rays emitted by analyte atoms on the surface of a thin sample (~ 100 microns). In this technique, a small quantity of the sample is deposited as a thin layer on a polished sample carrier. An incident primary X-Ray beam impinges upon the sample carrier at an angle below the critical angle of Total Reflection for X-rays.

The critical angle depends upon the polished carrier material and the incident X-Ray wavelength. Typical Critical angles range from 0.04⁰ for Plexiglass at 35keV to 0.55⁰ for Gold at 8.4 keV. The atoms in the sample, when excited by impinging primary X-rays, emit secondary X-rays (Fluorescence), which are counted and measured by a solid-state detector. The detector is placed directly above the sample at a distance of about 0.5 mm to 1 mm, to capture maximum Fluorescence radiation from the sample. The measured signal is analyzed by energy intensity, providing an energy dispersive spectrum. While measurements can be done in air, the TXRF can be performed in special chambers under vacuum or in the Helium atmosphere.

Common Uses of Total Reflection X-ray Fluorescence (TXRF)

• Trace and ultra-trace level elemental analysis in various fields such as Semiconductors, Food, chemical, biotechnology and metallurgical industries
• Non-destructive investigation of surface contamination and thin, near-surface layers of semiconductors
• Research in environmental sciences, geology, biology and medicine.
• Forensic analysis and Archaeometry

Advantages of Total Reflection X-ray Fluorescence (TXRF)

• Highly sensitivity even at ultra -trace levels of elemental analysis
• Quantitative and qualitative analysis
• Small sample size
• Non-destructive method
• Simultaneous analysis of multiple elements

Limitations of Total Reflection X-ray Fluorescence (TXRF)

• Polished surface
• Sample preparation is time consuming
• Not all elements are detectable

Industrial Applications of Total Reflection X-ray Fluorescence (TXRF)

• Semiconductors
• Chemical
• Biotechnology
• Metallurgy
• Environmental
• Medicine
• Geology
• Forensics