Trace metal analysis on hafnium silicate deposited Si wafer by Total Reflection X-ray Fluorescence

Hafnium silicate is a so-called high-k material, which is a new key material in the semiconductor field. This material is difficult to analyze by a conventional W-Lβ1TXRF source due to the high background originating from Hf-Lα lines. In this paper, the capability of Ir source TXRF analysis on hafnium silicate films is investigated with intentional contamination of Ti, Cr, Fe, Ni and Cu elements. The spectral fitting is discussed where X-ray resonant Raman scattering and escape peak of Ir-Lα overlap with Ni-Kα peak. The detection limits are estimated to 0.9 × 10¹⁰ to 2 × 10¹⁰ atoms/cm² for the transition metals.