Testbeds and applications provide a focus and incentive for strong integrative efforts within the Center. They also provide a mechanism for identifying research gaps and getting feedback on the relative sensitivity of applications to performance of the basic capabilities integrated within the Nano-CEMMS platform. To this end, the Center has chosen two application testbeds, (1) Heterogeneous Optoelectronic Device Manufacturing and (2) Combinatorial Chemistry Testbed.

A heterogeneous optoelectronic system is an attractive application for this purpose because:

• Its requirements match the target capabilities of the tool
• It is scalable, i.e., important devices can be made with micron scale features, and systems with high scientific and technical significance emerge as dimensions shrink to the nanometer regime
• Useful circuits components can be constructed with materials that are dissolved or suspended in aqueous and/or organic solvents
• High performance devices must be fabricated using additive schemes such as those embodied by the Nano-CEMMS tool, since heterogeneous integrated devices require assembly techniques that are compatible with diverse and dissimilar materials classes

In order to realize this application, the Nano-CEMMS tool must be able to:

• Print with nanometer resolution
• Pattern rapidly over large areas with massively parallel arrays of nozzles
• Exploit dry transfer printing methods for integration
• Perform multilevel registration with better than 100 nm overlay errors
• Pattern structures on flexible plastic substrates

Combinatorial chemistry, in very large arrays of nanometer-sized wells, eliminates a fundamental research challenge. Current combinatorial chemistry experiments are typically performed in microliter-sized well plates or in arrays of microliter-sized drops sitting on a surface. Two characteristics prevent this methodology from being scaled down much further:  (1) both the well plates and arrays of drops are exposed, allowing for undesired solvent evaporation (this effect becomes worse upon further downscaling due to the larger surface to volume ratio of smaller drops), and (2) the read-out systems to detect whether a combination is a positive result are all bulky and external. 

Arrays of wells in closed VLSI-mFNs eliminate the solvent evaporation problem. In the later years, we will also integrate detection elements that are capable of read-out on nanometer-sized compartments embedded in the VLSI-mFNs.