Reducing the Development Time for Chemical Instrumentation
The development of new instruments for chemical analysis by the physical chemistry community has had an enormous societal end economic impact. The CCU has established a set of industrial partnerships designed to expedite the translation of new measurement technology to commercial instruments [Tektronix, Virginia Diodes, Inc. (VDI) and Syracuse Research Corporation (SRC)]. The CCU is using this structure to innovate around a new broadband spectroscopy platform. VDI and SRC have agreed to host CCU students and work with the CCU to support them through the NSF GOALI program.
The technology that we are developing is the chirped-pulse frequency comb (CPFC), currently under a provisional patent protection. This technology is related to frequency combs from ultrafast laser spectroscopy that received the 2005 Nobel Prize (Hall and Hansch). Two areas outside interstellar chemistry that will benefit from this development are real-time gas analysis and biomolecular spectroscopy and dynamics. In the field of biomolecular spectroscopy, the THz region provides direct access to lowest frequency collective vibrational modes that underpin the large scale conformational dynamics important in function. For small crystalline solids, insight in the diverse dynamics displayed within classes of biosystems has come from comparisons of THz data with full quantum chemical modeling results. The recent integration of waveguide techniques has significantly enhanced spectral resolution (>5 fold) and sensitivity (>10 fold). Application of broadband THz methods to measure the backbone torsional modes of jet-cooled biomolecules will serve to validate, improve and uncover mode specific deficiencies in classical molecular dynamics simulations, force field models and quantum chemical theories in much the same way as jet-cooled MW studies have served as “structural standards” free of contamination by environmental contributions. The ~106 effective spectral elements of microwave spectroscopy allows the unique spectral analysis of mixtures of hundreds of components – even more if one uses supersonic cooling to readily achievable rotational temperatures of ~1 K. For components in a library, no ambiguity will exist, and (as discussed earlier) library free detection is highly promising. We foresee microwave spectroscopy ultimately becoming standard instrumentation of any analytical chemistry facility that studies molecules that can be put into the gas phase. Besides defense and homeland security applications that we expect to be some of the early adaptors, applications in medical diagnostics, forensics, industrial process control, and environmental monitoring are anticipated.
EUV Light Degradation of Mirror Surfaces Used in Advanced High Resolution Lithography
The CCU will also pursue innovation opportunities that arise from the novel chemistry that takes place under interstellar conditions. For example, the principles learned about surface photochemistry driven by Lyman-α radiation are directly transferrable to technologies which involve extreme ultraviolet light (EUV). Extreme resolution lithography approaching the sub 20 nm regime using 13 nm EUV light (at 93 eV photon energy) is currently a target in the microelectronics industry for the next generation semiconductor devices in 2013. A major problem with EUV-lithography is the photochemical degradation of hydrocarbon contaminants from the process vacuum at 10-6 to 10-7 Torr onto first surface mirror optics used in processing, causing polymerization-decomposition on the mirrors and optical degradation to the point of uselessness. It is envisioned that photochemically-driven cleanup methods may solve this problem, and John Yates is currently supervising a postdoctoral worker at NIST who is using the NIST synchrotron to investigate EUV- induced carbon deposition and carbon mitigation processes on model optical surfaces. Issues such as: (1) the cross section for molecular decomposition; (2) the role of secondary electrons; and (3) the photo-excitation of chemical reactions on surfaces, cross over between this developing technology and Lyman-α-induced photochemistry on oxide and carbon surfaces being studied for astrochemical purposes by Yates.
Pushing Chirped-Pulse Fourier Transform Spectroscopy to Millimeter-Wave Frequencies [Graduate Student Researchers Brandon Carroll, Justin Neill & Dan Zaleski]