SBIR Phase I: Atomic Force Microscope Active Optical Probe for Single Molecular Imaging and Optical Spectroscopy

This Small Business Innovation Research Phase I project is focused on proving the feasibility of atomic force microscopy (AFM) probes that enable nanoscale optical spectroscopy simultaneously with AFM imaging. The resulting product - an AFM Active Optical Probe (AAOP) - represents a cost-effective blend of two technologies: AFM probes and diode lasers. Current near-field scanning optical microscopes (NSOMs) and hybrid AFMs with specialized far-field optical microscopes have limited usefulness because of high cost and difficulty of use. Though AFM for surface characterization is highly developed, optical imaging at the nanoscale lags far behind. The envisioned AAOPs will be manufacturable at sale and will facilitate a cost reduction of 10 to 100 times as compared with competing instruments, while outperforming them in image quality and ease of use. The initial market focus of this effort will be on the AFM market (currently $110 million), with a later expansion into the combined spectroscopy and nanotools market of $9.7 billion. As one example of the expected impact of this product, the AAOP technology will be used by researchers and industrial scientists for single molecule studies, biomedical sample analysis, and for microlenses and nanophotonic devices?all at a substantially lower cost than competing technologies. The AAOP product will combine a micrometer-sized diode laser, an optical photo detector, and an AFM probe on a single semiconductor chip. These unique optical probes will perform the functions of conventional AFM probes and will simultaneously provide specimen information about optical properties at the nanoscale. This represents a cost-effective alternative to expensive NSOM tools, and to hybrids of AFMs with specialized far-field optical methods such as confocal, Raman, fluorescence, and Fourier transform infrared spectroscopy. The AAOP will address the technical challenges of current NSOMs; namely, background noise and low sensitivity. This effort will demonstrate the technical and economic feasibility of the AAOP, fitting it onto a conventional AFM, an instrument that is widely used in both academia and industry. The anticipated technical results will provide AFM users the ability to carry out nanoscale optical studies and characterization with better resolution and higher sensitivity, at much lower cost, and more quickly than is possible with conventional NSOM and Raman AFMs.