Nanoscale Sensing Technologies
The Center is engaged in the development of high resolution sensing technologies for the operation of its nanoscale manufacturing processes as well as the development of sensing technologies that can be produced from the nanoscale dots, lines, patterns and structures created by the Center developed nanomanufacturing processes.
The need for nanoscale toolbit positioning as well as nanoscale monitoring and process control of fluids in the toolbit is essential to several of the Center's processes. Sensing technologies based on electronic and photonic sensing elements are being developed and incorporated into the basic manufacturing platform and toolbit control.
There are three general areas of research directed toward fluidic-based nanomanufacturing:
- Very Large Scale Integrated (VLSI) microfluidic networks for micro/nano fluidic components
- Nanoscale sensing of composition and position
- Nanoscale positioning and process control
VLSI microfluidic networks with embedded control elements are being developed and fabricated by the Kenis group. Nanoscale chemical composition and position sensing elements based on electronic and photonic sensing are being developed and fabricated by Choquette, Cunningham and Fang and integrated into the Nano-CEMMS manufacturing platform by Ferreira, Cunningham, and Kenis. Nanoscale positioning and process control developments are a cooperative effort with the Fang, Choquette, Ferreira and Alleyne groups.
Among the developments in microfluidic network sensing is the collaborative effort between Kenis and Choquette who have fabricated a hybrid integration of vertical-cavity surface-emitting lasers (VCSELs) with a network of microfluidic channels for in-situ chemical sensing. These systems based on optics and fluidics provide new opportunities for miniature biomedical diagnostic devices. Integration of VCSELs with microfluidics can be used for absorption and fluorescence based sensing of concentration and composition.
Optical image of three sensing configurations of a VCSEL surrounded by a PIN detector.
Choquette has also developed optical position sensing element based on a nano-aperture Vertical Cavity Surface-Emitting Laser (VCSEL) that employs surface plasmons generated by metal nano-structures on the top facet of the laser. Sub wavelength metal apertures on VCSELs can create small, high-intensity near-field spots. Choquette has developed a method to reduce the large angular divergence for sub-wavelength apertures while increasing the intensity by 2.25 by patterning periodic concentric corrugations in the metal surrounding the opening.
Lu, Rogers, Fang and Ferreira have collaborated to produce high resolution e-jet printed high-density DNA arrays and S4 silver patterned arrays for colorimetric detection of specific molecules in analytes.
Our nanomanufacturing processes can create some of these sensing elements as well as other nanoscale chem/bio, thermal and metrology sensing elements including:
- Photonic crystal sensing structures in microfluidic networks for chem/bio sensing
- Metallic patterns for Surface-Emitting Raman Spectroscopy (SERS) and fluorescence spectroscopy sensing structures
- Nanowire sensors
- Micro-cantilever structures for sensing thermal-mechanical properties and characterization of nanoscale domains
- E-jet "printed" high density DNA dot arrays for colorimetric sensing of specific molecules
The Center is developing new technologies to manufacture nanoscale dots, lines, patterns and structures and simultaneously sensing applications that utilize these patterns and structures on a massively parallel scale for combinatorial chemistry, bioassays and diagnostic devices