Micrometer to 15 nm Printing of Metallic Inks with Fountain Pen Nanolithography

Abstract

The field of printed electronics is continually trying to reduce the dimensions of the electrical components. Here, a method of printing metallic lines with widths as small as 15 nm and up to a few micrometers using fountain pen nanolithography (FPN) is shown. The FPN technique is based on a bent nanopipette with atomic force feedback that acts similar to a nanopen. The geometry of the nanopen allows for rapid placement accuracy of the printing tip, on any desired location, with the highest of optical sub‐micrometer resolution. Using this nanopen, investigations of various inks are undertaken together with instrumental and script‐tool development that allows accurate printing of multiple layers. This has led to the printing of conductive lines using inks composed of silver nanoparticles and salt solutions of silver and copper. In addition, it is shown that the method can be applied to substrates of various materials with minimal effect on the dimension of the line. The line widths are varied by using nanopens with different orifices or by tailoring the wetting properties of the ink on the substrate. Metallic interconnections of conducting lines are reported.

Gravure Printing of Water-based Silver Nanowire ink on Plastic Substrate for Flexible Electronics

“…Printed electronics has drawn tremendous interest in the past few decades 1 – 6 , as it offers an attractive alternative to conventional silicon-based fabrication technologies by enabling low-cost, large-area, flexible devices for many applications such as energy storage 7 , thin film transistor 8 , light-emitting diodes 9 and wearable sensors for health monitoring 10 . Central to this technology are high-performance functional inks and high-throughput printing methods, such as screen 11 – 15 , inkjet 16 – 18 , gravure 19 , 20 and flexographic printing 21 .…”

Controllable Melting and Flow of Ag in Self-Formed Amorphous Carbonaceous Shell for Nanointerconnection

“…The versatility of this proposed metal filling method is comparable to the developed welding method at macroscale, allowing the selection of interconnection materials based on the welding requirements. It is foreseeable that this metal-filled a-C shell can also be used in various promising applications such as nanoprinting [21], nanoscale circuit direct writing [32], and field effect transistor (FET) fabrication [33]. We believe that the proposed metal filling method, and its controllable melting and flow, open new possibilities for nanoscale interconnection.…”

Emerging Scanning Probe–Based Setups for Advanced Nanoelectronic Research

“…SEM images of b) the structure of probe, c) the nanopen aperture, d) printed 12 interconnections over a gap of 850 nm, and e) copper connection between Au line and big pad. Reproduced with permission . Copyright 2017, Wiley‐VCH.…”

“…In ref. , the authors printed 12 conductive interconnections on a pre‐patterned chip through nanopens (1 µm orifice), which was filled with 40 nm silver particles (dispersed in a glycol‐based dispersion, 55 wt%). It is noted that the chip has 15 separate gold electrodes, which are with the size of 80 nm in height, 3 µm in width and gap separations of 350 and 850 nm.…”

“…The metallic ions in the salt solution will be reduced to metal upon heating, and this should form a metallic line. It has been reported that a copper formate (one kind of salt) was utilized to pattern a 15 nm wide conductive connection between a gold line and a big pad, here they used a orifice with the diameter of 200 nm . As shown in Figure e, a long and continuous narrow copper connection has been successfully fabricated and it has a width of 15 nm and a height of 20 nm.…”