High resolution scanning probe microscopy techniques combined with infrared (IR) light sources offer unique solutions to combined chemical/mechanical/electrical characterization of defects in nanoscale dimensions. Previously, atomic force microscopy combined with infrared (AFM-IR) technology has demonstrated its capability to characterize nano-patterned metal/low-k dielectrics, nanoscale organic contaminants, and directed self-assembly of block co-polymers used for advanced micro/nanofabrications. In this paper, two complementary nanoscale chemical analysis techniques, photothermal AFM-IR and scattering type scanning near-field optical microscopy, are implemented to isolate and characterize microelectronic device cross-sections. It is observed that both techniques are able to detect patterned features with a half-pitch less than 15 nm.

Atomic force microscopy infrared (AFM-IR) technology combines the best of both worlds of AFM and IR spectro-microscopy offering high spatial resolution chemical characterization. Recent developments in the AFM-IR technique, such as tapping AFM-IR pushes the spatial resolution limit below 10 nm, making it ideal for chemically characterizing directed self assembly (DSA) components and defects for failure analysis. This paper demonstrates the chemical characterization of DSA nanopatterns using tapping AFM-IR technology with spatial resolution beyond 10 nm. Tapping AFM-IR experiments is performed on different block copolymers routinely used to fabricate directed self-assemblies on Si wafers. Along with chemical mapping, mechanical properties, such as relative stiffness and damping yielding complete chemical and mechanical property information in nanoscale to achieve material contrast, can be simultaneously probed.

Continuous development in the semiconductor process technology has led to the fabrication of devices with nanometer scale feature resolution. Resonance enhanced atomic force microscopy infrared (AFM-IR) is a novel technique with potential to overcome some limitations of existing tools. This manuscript illustrates chemical characterization of the nanoscale skin and polyester contaminant on silicon wafer using resonance enhanced AFM-IR spectroscopy. Resonance enhanced AFM-IR offers superior sensitivity for nanoscale organic contaminants. To demonstrate this capability, AFM-IR spectra were obtained from contaminants on silicon wafers, and the spectra correlated with a high confidence to a standard transmission FTIR spectral database. In addition, a newly developed high speed spectral acquisition scheme, which augments the reliability of nanoscale defect characterization by reducing the overall data acquisition time and enabling users to perform repeated measurements for statistical analysis, is established.

Spectroscopic characterization of interconnects and circuits in semiconductor devices has become increasingly complicated as dimensions for breakthroughs and failure analysis are continuously shrinking. To achieve high spatial resolution infrared (IR) spectroscopic information, a pulsed infrared laser can be coupled to an atomic force microscope in the atomic force microscopy IR (AFM-IR) technique. The combination of AFM-IR and Lorentz contact resonance AFM (LCR-AFM) has great potential for providing high spatial resolution chemical and mechanical analysis. To demonstrate the feasibility of the AFM-based techniques, AFM-IR spectrum and images were obtained from the interlayer dielectrics of a test structure at a length scale shorter than the IR wavelength. Using the LCR-AFM technique, the relative mechanical properties of the components could be mapped distinctively by observing the contact resonance of the AFM probe. Finally, preliminary data suggest there may be AFM-IR spectral differences between contamination and the bulk material on a liquid crystal display.