In keeping with changing times, the increasing demands for devices miniaturization and technological advances have been made in every field which has generated a vast interest among researchers. Until recently, the miniaturization technology has improved by leaps and bounds. In search of ways to overcome the obstacles of miniaturization, a method has emerged that allows the creation of circuits by pressing the imprinting of a nanometer-scale mask onto the substrate in a process called “nanoimprinting”.
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Nanoimprint technology has become an alternative to conventional lithographic technology and manufactures nanostructures for various applications in many areas of nanoscale device manufacturing, from more standard semiconductor devices.
Nanoimprint lithography provides high precision, cost-effective technique, high through-put and single exposure method to replicate nanoscale features below 10 nm, and a promising solution to the practical limits of photolithography, the current advance technology in semiconductor lithography. Nanoimprinting has overcome tremendous difficulties over the past 20 years to become a realistic method for commercial semiconductor production.
Canon inaugurates in a new era of miniaturization by developing the most advanced unique and powerful equipment in the world, based on totally innovative technology. Last year, Toshiba installed the latest nanoimprint lithography system of canon in Japan named “FPA-1200NZ2C”.
Working Principle of Nanoimprinting
The principle of Nanoimprint lithography is straightforward. Nanostructured silicon or polymer hybrid mold is pressed with controlled pressure and temperature on a substrate coated with a defined layer of polymeric material. After the removal of the mold, an inverse reproduction of the characteristic will then be directly imprinted on the substrate.
Recently new polymer resist has appeared on the market and has been used for nanoimprinting technology. This UV based nanoimprinting process makes it even simpler and faster than the traditional hot embossing technique because it can be done at room temperature.
The only requirement is then to have a transparent mold which allows the UV light to pass through for the curing of the resist. The most common process is first to create a transparent stamp of the original template and then use this stamp for the replication process of the resist dispersed onto the substrate.
The PDMS Poly (dimethylsiloxane) is commonly used for the fabrication of the transparent stamp. This material offers a very high-resolution patterning and is also easy to separate from the mold due to its low surface energy.
Nanoimprint technology, however, doesn’t require expensive optics, multiple patterning, and shorter-wavelength light-sources. Instead, it uses the simple approach of physically applying a mask into which the circuit patterns have been cut. This approach not only has the potential to reduce costs significantly, but it also produces extremely clear circuit diagrams and should help minimize chip failure rates.
Applications of Nanoimprinting
Nanoimprinting provides a cost-effective pathway for much more precise control of surface optical properties and has been exploited for numerous applications such as fabrication of active photovoltaic layer in solar cells, control of polarization, color, media for hard-disk drives. As well as being used in biological applications include sensing, nanofluidic devices for DNA stretching, tissue engineering.
Nanoimprinting is capable of replicating features below 10 nm over large area substrates, is a leading candidate to allow nanostructures manufacturing for advancing ICs. Smart devices are displacing personal computers and current household devices. The semiconductor industry has shifted design goals to include minimizing of power consumption. The market for mobile dynamic RAM continues to grow owing to smartphone demand for upgrading memory efficiency and performance; the industry will continue to struggle for process improvements beyond the 14 nm to reduce feature size.
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