Quantitative Analysis of Trace Metallic Contamination on III-V Compound Semiconductor Surfaces

Abstract

We studied the detection by TXRF of several transition metals on the surface of III-V materials for high mobility channel. It has been found that the lower limits of detection of some transition metals on the surface of III-V materials become higher than that on the Si surface because the sum peaks or Raman scattering peaks as well as the fluorescent X-ray main signals from the materials themselves partially cover those from the transition metals

(Invited) Metallic Contamination Issues in Advanced Semiconductor Processing

“…Drops consisting of HF and HCl also restrain Si from supplying electrons to Cu ions in the liquid drops and thus reducing Cu on the Si surface. When III-V compound semiconductor materials are introduced for high mobility channels, the detection sensitivity on the III-V semiconductor surface by TXRF [10] and the metal collection efficiency [11] becomes critical issues. Figure 3 shows TXRF spectrum of the InGaAs surface contaminated with metals whose concentration is equivalent to 1 × 10 11 atoms/cm 2 .…”

“…Figure 4: TXRF spectra of (a) Si surface and (b) InGaAs surface contaminated with the metals, whose concentration is equivalent to 1 × 10 11 atoms/cm 2 (magnified at 6.2 keV ~7.2 keV).The lower limits of detection of the Cr, Mn, Fe, Ni, Cu, Zn, W, and Mo on the InP, InAs, InGaAs, GaAs, and GaSb surfaces have been determined by considering the interfering peaks such as sum peaks and resonant Raman scattering peaks[10]. The lower limit of detection has been defined.…”