Nanolithography in a nutshell
An introduction to the technology that drives ARCNL research
Lithography is the process of printing a pattern onto a material using light. Nanolithography is the same, but for patterns with features on the scale of nanometers (one millionth of a millimeter). (Nano)lithography processes are used in printing computer chips, which are ubiquitous in every area of daily life – from your smartphone and laptop to medical equipment and navigation systems.
Inside the nanolithography machine
The most advanced nanolithography machines use extreme ultraviolet (EUV) light, which has a wavelength of 13.5 nanometers.
While EUV light occurs naturally in space, to make it on Earth, we use high-powered lasers to turn liquid tin droplets into a hot, dense plasma. This plasma is a source of EUV light.
The Source Department at ARCNL studies all aspects of this process, including plasma and fluid dynamics, drive laser physics, ion interactions, and the atomic origins of the EUV light.
The EUV light leaves the source chamber and enters a system of specially designed mirrors. These mirrors direct the light onto the reticle, which is a stencil of the pattern to be printed onto the chip, and then onto the silicon wafer.
Because many chips are printed on a single wafer, this process is repeated many times as the wafer moves horizontally at high accelerations.
The mirrors and other internal parts of the machine have to withstand extreme physical conditions, making robust materials, protective coatings, and nanoscale friction and wear important areas of research. These are topics that ARCNL’s Materials Department focuses on.
At the same time, it’s very important that the layers of a computer chip are aligned with each other – otherwise the circuits are not connected properly.
In order to measure this alignment during the nanolithography process, measurement techniques need to be extremely precise and non-invasive, all while balancing energy efficiency and cost-effectiveness.
The Metrology Department at ARCNL investigates diverse approaches to nanoscale measurement techniques. This involves lensless and computational imaging, coherent light sources that range from infrared to soft x-rays, and advanced optical detection schemes.
Academia-industry collaboration
While ARCNL is a fundamental research institute, our research programs are inspired by the challenges presented by developments in nanolithography technology and the broader semiconductor manufacturing industry. To this end, we work closely with our industry partner, semiconductor equipment manufacturer ASML.
