Rapid Prototyping for R&D

New substrates, resists, materials and complex geometries with small feature sizes are essential for cutting-edge discoveries in nanotechnology with applications ranging from quantum physics, data communication and computing devices, novel optical components to biological sensors, stem cell research and DNA sequencing. Advanced and novel nanodevices for all these applications demand precise control of size, shape, and position of the involved nanostructures. Maskless lithography technologies are therefore crucial for any R&D activity as several iterations are usually required for the development of such new nanodevices.

The NanoFrazor’s maskless nanofabrication technique is particularly suited for prototyping in R&D because of its general applicability to various materials and surfaces. The unique technology features take this a few steps further and facilitate the fabrication of novel nanodevices and nanopatterns not possible with any other existing nanofabrication methods.

The unmatched resolution for 3D structures of the NanoFrazor is particularly interesting for optical components where some promising new materials are known to be damaged or destroyed using conventional nanolithography methods. The NanoFrazor can fabricate such nanodevices using 2D materials, topological isolators or nanowires without damaging them.

Moreover, time can be saved and complexity can be reduced as no resist development or optical proximity corrections are required by the NanoFrazor. The in-situ metrology capabilities allow for an instantaneous feedback and real-time adjustments to the written nanostructures for a greatly reduced turnaround time, as compared to e-beam lithography. Furthermore, markerless overlay using underlying features saves time for creating the markers and allows for a high alignment accuracy.

NanoImprint Lithography Stamps

Nanoimprint lithography (NIL) is an emerging high-throughput nanolithography technique. It requires stamps whose patterns are almost identically replicated in a resist by either thermal imprinting (T-NIL) or UV curing (UV-NIL). Even complex high-resolution 3D-structures can be mass-manufactured from 3D stamps with high fidelity and throughput.

The NanoFrazor allows the fabrication of such precise stamps for NIL. A very simple approach has been demonstrated in collaboration with EV Group using their SmartNILTM process, whereby the SmartNIL stamp was cast directly from a PPA film patterned by the NanoFrazor Explore. Besides that, stamps can also be made by transferring the PPA pattern into various hard materials like silicon, nickel and quartz by reactive ion etching or electroplating.

Molds

Injection Molding is the most common technique for mass manufacturing plastic parts of any kind. It is less known for nanotechnology, even though it is also capable of replicating 3D nanostructures like nanoimprint lithography.

The NanoFrazor Explore offers unique capabilities for this mass manufacturing process, e.g. to incorporate 3D nanostructures into plastic parts. This process has been demonstrated and published in collaboration with the company applied microSWISS and the Fachhochschule Nordwestschweiz (FHNW). A 3D nickel shim was made directly from 3D PPA patterns through electroplating. The shim was then used in a next step to replicate these 3D nanostructures into PMMA using vario-thermal injection compression molding.

Photolithography Masks

Low-resolution photolithography masks are usually fabricated by laser writers which achieve high throughput at a reasonable cost. For high-resolution masks fabricated by e-beam lithography, challenges like throughput, placement accuracy and critical dimension increase dramatically for the next generation computer chips especially due to complex optical proximity correction (OPC) requirements.

OPC structures can potentially be improved by introducing 3D features to the mask, making it a suitable target market for the NanoFrazor Industrial. A further advantage of the NanoFrazor technology is its in-situ inspection capability, which can potentially save some of the expensive metrology steps during the mask-making process.

Small Series & Customized Products

Throughput of high-resolution maskless nanolithography techniques are orders of magnitudes lower than that of optical lithography and other replication technologies. However, not all high-resolution nanolithography devices require densely packed structures throughout the wafer like memory and logic devices with billions of transistors per unit.

Highly-specialized products that require complex, high-resolution features or other special functionalities often do so only in certain areas. These can be small 3D optical components, high resolution vertical electrical contacts or tiny surface functionalizations for biosensors, for eaxample. The NanoFrazor Industrial can be a cost-effective enabler or an alternative for manufacturing such products.

Using its in-situ metrology capabilities, the high-resolution parts can be written next to the low-resolution areas by Mix-and-Match. This can be done with a minimal overlay error with respect to the underlying structures, even without the use of any alignment markers. This alignment method also does not suffer from dose redistribution due to backscattering, unlike electron or focused ion-beam lithography, and substrate damage is avoided through the absence of charged particles.

NanoFrazor image of a high resolution 8-level hologram written in PPA and etched 700nm deep into Si (SEM image inset)
Mix & Match fabrication of Single Electron Transistors in Si using a combination of photolithography, DLS laser sublimation and NanoFrazor Lithography
Sine wave and rectangular box etched 300 nm deep into Si and then replicated with OrmoStamp and imprinted into OrmoClear. Roughness is 3.3 nm (1sigma)
Nickel shim of the 3D map of Switzerland electroplated from PPA and used for injection molding
Simple and accurate overlay of electrodes on a randomly assembled nanowire without damage from a charged particle beam
Topography image of single layer MoS2 flake buried under resist with overlay pattern in PPA with the NanoFrazor
Blazed Grating designed as more efficient optical fiber coupler
High resolution gold trimer as plasmonic resonator
Multilevel hologram as master for NIL
3D Phase Plate for transmission electron optics etched in SiO2 (Credit: Simon Hettler, KIT)
Gold grating with 18 nm half-pitch