Dpn

DPN (Dip Pen Nanolithography)




Dip Pen Nanolithography The DPN process was first developed by Professor Chad Mirkin at the Northwestern University Nanotechnology Institute for depositing thin organic films in patterns with feature sizes of around 10 nm (about 20 times better than the best optical lithography). Coating an Atomic Force Microscope (AFM) tip with an ink, the scientists are able to deposit well defined lines of the ink in a manner similar to a traditional ink pen. NanoInk has created a dedicated DPNWriter system, NSCRIPTOR™, as a fully-integrated hardware and software system that is optimized for the DPN process.

http://www.nanoink.net

Schematic of the DPN process.

http://www.nanoink.net

DPN ink- substrate

NSCRIPTOR™ NSCRIPTOR™ allows the user to perform the following basic DPN tasks: 1. Design DPN patterns 2. Prepare the working environment 3. Write the DPN patterns 4. Inspect the DPN patterns

http://www.nanoink.net

NSCRIPTOR™

NSCRIPTOR™ combines hardware and software

http://www.nanoink.net

DPN Hardware The hardware system for NSCRIPTOR™ provides optimal performance, both in writing and image acquisition

http://www.nanoink.net

DPN Hardware DPN Stage size: 16” x 16” x 14” Color CCD video camera with motorized zoom (4X) and focus capability 3 independently adjustable Z motors serve to level the plane of the scanner assembly DPN Scanner: 90 micron scan X-Y range with placement precision better than 10 nm Maximum sample size: 2” across, < 1.5” thick

http://www.nanoink.net

Environmental Chamber The Environmental Chamber is an integral part of the NSCRIPTOR™ system, as it controls the process environment for DPN experimentation. The chamber houses the entire DPN stage. Temperature and humidity sensors monitor the enclosed environment in real time, and both parameters are controlled by PID feedback loops

Humidity Range: Set Point Stability: Temperature Range: Set Point Stability:

http://www.nanoink.net

5 – 75% Rh
0.5 % Rh - 2C above room Temp to + 10C above
0.2 C

DPN Software -- InkCAD™

features are organized following the theme of layering for ink design

http://www.nanoink.net

InkFinder™ InkFinder allows for micro-scale alignment of the sample relative to the tip, whether or not the sample or tip position has changed during the time between writing several layers.

InkAlign™ InkAlign™ is used to provide the nano-scale alignment between different ink pattern layers, which is critical for multi-ink, multi-pen integration.

InkCal™ InkCal™ allows InkCAD to account for an ink’s molecular diffusion properties, providing empirical experimental control over resulting nanolithography object sizes. InkCal writes and measures dot diameters and line widths, written at various speeds, and then uses empirical measurements of the drawn dots or lines to calculate a diffusion coefficient.

InkCal™ • for precision and accuracy of feature size

http://www.nanoink.net

Type A single DPN probes

http://www.nanoink.net

Type B single DPN probes

http://www.nanoink.net

Type C multi-probes

http://www.nanoink.net

Type D multi-probes

http://www.nanoink.net

http://www.nanoink.net

Active™ Pen Arrays

• 8 pen array • 6 writing pens • 2 reader probes

Heating element Heat spreader

Inkwell http://www.nanoink.net

Thermally Actuated Probe Arrays for Dip Pen Nanolithography

The TA-DPN probe operational concept. Unactuated probes are cold and sit on the surface where they deposit ODT at room temperature. Actuated probes lift away from the surface and do not deposit ink.

JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, VOL. 13, NO. 4, P 594, 2004

Thermally Actuated Probe Arrays for Dip Pen Nanolithography

Ten different DPN patterns written simultaneously by the ten probes of a TA-DPN array. Deposited ODT shows up dark in these 8 um x8 um LFM scans.

JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, VOL. 13, NO. 4, P 594, 2004

More Speed: “Pen” Arrays

http://www.nanoink.net

More Speed: “Inking” Systems

Microfluid system delivers chemicals to inking apertures

Ink wells are in registry with a tip array.

http://www.nanoink.net

NANO FOUNTAIN PROBE FOR SUB-100 NM FOUNTAIN-PEN WRITING

(a) Schematic of the device. With an ink solution placed on the reservoir, the solution fills the channel by capillary action to reach the end of the dispensing tip. Molecules are transferred by diffusion from the liquid interface to a substrate through diffusion process and water meniscus. (b) five nano fountain probes on the chip (c) the reservoir side of the chip. (d) cross-section of a cantilever showing embedded microchannels (e) (e) a volcano tip at the end of the cantilever. Keun-Ho Kim, Nicolaie Moldovan and Horacio D. Espinosa Department of Mechanical Engineering, Northwestern University,

Thermal dip pen nanolithography

At low temperatures, the ink is frozen on the cantilever preventing transfer

At high temperatures, the ink melts and transfers from the tip to the substrate

P. E. Sheehana) and L. J. Whitman, APPLIED PHYSICS LETTERS : VOLUME 85, NUMBER 9, P1589, 2004

Thermal dip pen nanolithography

Cantilevers were coated with Octadecylphosphonic acid (OPA) Substrate: Mica

P. E. Sheehana) and L. J. Whitman, APPLIED PHYSICS LETTERS : VOLUME 85, NUMBER 9, P1589, 2004

Thermal dip pen nanolithography

P. E. Sheehana) and L. J. Whitman, APPLIED PHYSICS LETTERS : VOLUME 85, NUMBER 9, P1589, 2004