The world's first diamond nanoprobe tips demonstrate success in nanomanufacturing
In their groundbreaking work, researchers at Illinois, the Naval Research Laboratory, the University of Pennsylvania, and Advanced Diamond Technologies (ADT), have demonstrated that nanometer-scale diamond tips exhibit unparalleled stability and anti-fouling capabilities under extremely harsh conditions.
"The UNCD probe tip, integrated onto a silicon heater-thermometer, has extraordinary longevity and demonstrates success under the harsh conditions required for tip-based nanofabrication," said team leader William P. King, a Willett Faculty Scholar and an associate professor in the Department of Mechanical Science and Engineering at Illinois. "There are countless applications where we would like to have a nanoprobe scan over a hard surface at high temperature and high loading force."
According to King, the initial UNCD tip radius can be as small as 15 nm, and retains its shape when scanned for more than a meter at high temperatures and under high loading forces. Silicon tips, frequently used in prototype nanomanufacturing demonstrations, are quickly destroyed under similar conditions. Additionally, silicon tips easily foul, or pick up undesirable material from the scanned surface, while the low stiction properties of diamond avoid fouling.
Tip-based nanofabrication is the ability to use a nanometer-scale tip to imprint or write patterns onto a material; which is comparable to using a pencil to write on paper. In the nanoworld, writing tiny patterns is extremely difficult. Tip-based nanomanufacturing is currently used to fabricate or repair nanoelectronics or lithographic masks; a demanding job requiring the tip to scan long distances over hard substances. These wear resistant diamond nanoprobe tips integrated with silicon heaters are perfectly suited for nanomaterials characterization, nanoscale transport measurements, and applications such as dip-pen nanolithography, probe-based non-volatile memories, and patterning nanowires on surfaces.
Next, the researchers will be building and using arrays of these probe tips.
"The longevity of these probes allow them to be implemented in massively parallel arrays that could scan over long distances and at high speed," said King. "We can now think about using nanoprobe tip arrays to address many square centimeters of surface area. Eventually we'll go to nanoprobe scans on a meter scale."
DARPA's Tip-Based Nanofabrication Program sponsored this work.
Contact: William King, Department of Mechanical Science and Engineering, 217/244-3864.
Writer: Jill Jackson, 312/231-9870.
If you have any questions about the College of Engineering, or other story ideas, contact Rick Kubetz, Engineering Communications Office, 217/244-7716, editor.