The advent of microcalorimetry for x-ray detectors holds the promise for high-resolution compositional microanalysis applicable to nanometer-scale devices and structures. To demonstrate this capability, microcalorimeter-based energy dispersive x-ray spectroscopy (EDS) analysis has been used to analyze ultra-thin TaSiN films under development as ion diffusion barriers in sub-0 micro integrated circuit (IC) interconnect devices. We present compositional analyses of TaSiN films carried out using microcalorimetry-based EDS for comparison with similar data acquired using conventional Si(Li) EDS detectors. The elimination of elemental peak overlaps provided by the improved energy resolution of the microcalorimeter x-ray detector is demonstrated for TaSiN EDS spectra from films as thin as 3.5 nm. In addition, by varying the electron probe beam energy, we demonstrate the ability to control the x-ray generation volume within the investigated films. This greatly enhances the suitability of microcalorimetry-based EDS as a characterization/metrology technique for ultra-thin films used for microelectronic by enabling the use of lower electron beam energies leading to smaller x-ray generation volumes.
Proceedings Title: Proc., IEEE 2001 International (Interconnect Tech. Conf.)
Conference Dates: June 3-6, 2001
Conference Location: Burlingame, CA
Pub Type: Conferences
energy-dispersive spectrometry (EDS), film thickness microcalorimeter, TaSiN barrier layer, thin film metrology