SBIR Phase I: Nanometer scale Raman force microscopy for topographic, strain, and chemical analysis

This Small Innovation Research Phase I project aims to demonstrate the feasibility of the Raman Force Microscope (RFM) to provide a new metrology tool for in situ topographic, strain, and chemical analysis with nanometer spatial resolution. Feature size reduction in the semiconductor industry requires that metrology methods must routinely measure properties down to the atomic scale. Novel materials and geometries add to the complexity of measurements. RFM technology is a combination of Raman microscopy and atomic force microscopy (AFM), where an AFM tip provides a nanometer scale light source to generate stimulated Raman scattering, and at the same time measures the force gradient arising from the Raman scattering. The use of the AFM tip as the Raman scattering detector significantly simplifies Raman signal acquisition and system configuration. By combining a high-speed AFM scheme, this technology allows for in-line characterization of physical and chemical properties of nanoscale materials and structures in the manufacturing environment, i.e. stress in the channel layer and chemical characterization defects. The objectives of the proposed Phase I study are (1) to demonstrate reflection mode RFM for Raman signal measurement of Si wafers and (2) to demonstrate measurement of stress-induced Raman shifts in nanometer-sized features. The broader impact/commercial potential of this project will be felt not only in the semiconductor industry but across many disciplines and industries, both in academia and industry. RFM can be used to measure and characterize a wide variety of nanoscale materials and structures, e.g. high- and low-k dielectric films and other emerging materials (such as graphene) used in advanced semiconductor processes. It can be also widely used across disciplines, e.g. for the measurement of nanoparticle homogeneity or optimization of self-assembled monolayers in surface chemistry. The RFM technique also has the capability to image individual biomolecules in situ, such as for the real-time monitoring of membrane protein dynamics on cells, which will provide unprecedented utility in biomedical and clinical research. A reliable label-free imaging tool with the capability to identify chemical bond information at the molecular level will potentially bring about revolutionary advances in many fields of basic and applied biological science, including drug discovery, proteomics, structural biology, and personalized medicine. The RFM technique will be simpler to implement as compared to other hybrid instruments involving high resolution microscopy, resulting in an affordable instrument for academic and research institutions.