IARPA posts nanofabrication RFI
On August 24, the Intelligence Advanced Research Projects Activity (IARPA) posted a request for information (RFI) for biologically templated nanofabrication. Responses are due by 5:00 p.m. Eastern on September 24.
IARPA is seeking responses to this RFI that suggest integrated approaches to biotemplated nanomanufacturing of functional microelectronic devices that address any of the research opportunities listed above. Responses to this RFI are asked to address the following questions targeting a specific approach or concept, sorted into 3 categories: (a) biomanufacturing processes, (b) registration capabilities, and (c) devices and architectures.
Through registration of materials at the nanoscale (i.e., position and orientation), precision nanofabrication is approaching near atomic control of physical properties and electromagnetism, thus enabling a broad range of technology sectors. The primary beneficiary has been the microelectronics industry where advances have contributed significantly to gains under Moore’s law. More broadly, these techniques enable applications such as photonics, sensors, pharmaceuticals, textiles, and metamaterials.
As these application spaces mature and look forward over the next 30 years, fundamental limitations of existing materials and fabrication techniques are close approaching. Non-traditional materials, such as carbon nanotubes, quantum dots, meta-chalcogenides (e.g., MoS2), and (semi)conductive polymers, have been proposed to enable desired capabilities and novel nanofabrication techniques are required to incorporate these materials into functional devices (e.g., transistors, optical amplifiers, molecular sensors) and larger architectures. Pioneering work has shown that controlled registration of such materials at the nanoscale (< 20 nm) is challenging, and existing methods suffer from limitations that can affect device performance.
Optical lithography-based patterning, coupled with material deposition and etching techniques, have been used since the late 1950’s to fabricate sub-micron and nanoscale devices. Optical lithography trades high-throughput, wide-area patterning for diffraction limited dimensional scaling, with increasing defect rates as features approach resolution limits.
Emerging techniques, such as directed self-assembly, self-limiting reactions, and selective deposition, have shown utility as lithographic resolution enhancing tools to overcome this limitation. Such methods overcome resolution limits through two means: density multiplication, where the pitch of patterned material domains can produce denser features than those of a relatively large guiding pattern; and critical dimension shrinkage, where the critical dimension of the patterning material can be much less than that of the guide pattern. Synthetic polymer-based approaches, such as directed self-assembly, have addressed scalability issues but are limited to continuous 2D patterns over large areas, and lack the ability to arbitrarily register materials within a guide pattern.
Biologically templated nanofabrication techniques employ sequence-controlled biopolymers, such as DNA, RNA, and proteins, as scaffolds to template other functional materials. This is accomplished through two defining attributes: these biopolymers can be designed to take advantage of complementary physical interactions to self-assemble into practically any imaginable shape in two or three dimensions; and individual monomers within each polymer, spaced at sub-nanometer distances, can be chemically conjugated to functional materials permitting registration at near-equivalent length scales.
These attributes have been employed to program the structure and dynamics of nanometer-scale devices and materials. When employed in combination with existing fabrication technologies, new fabrication paradigms emerge.