Engineering the Future: Patrícia Sousa on the Challenges and Innovations in Micro and Nanotechnologies

Introducing Patrícia Sousa, a pioneering Research Engineer in Integrated Micro and Nanotechnologies at INL. With a strong foundation in Chemical Engineering and a Ph.D. in Chemical and Biological Engineering from the University of Porto, Patrícia has specialized in microfluidics and advanced fabrication techniques that address critical challenges in micro and nanotechnologies.

Patrícia’s dedication extends beyond the lab, as she actively participates in public outreach initiatives, including the European Researcher’s Night and educational programs in local schools. There, she shares her expertise in accessible and inspiring ways, illustrating how nanotechnology can transform fields such as medicine, electronics, and sustainability. In this interview, Patrícia offers insight into her career journey, the challenges and triumphs in her work, and her passion for making science accessible and impactful for all.

Could you briefly describe your academic and professional background in micro and nanotechnologies?

My academic background includes a first degree in Chemical Engineering, from the Faculty of Engineering, University of Porto followed by a PhD in Chemical and Biological Engineering, also from the Faculty of Engineering, University of Porto. Since my PhD studies focused on microfluidics, at that time I started deepening my knowledge in the field of micro and nanotechnology and in particular, micro and nanofabrication processes which were relevant for the fabrication of the devices required for my investigations.

Since I am working here at INL, I have been working in surface nano-structuring and micro- and nano-fabrication for different applications such as micro optical devices, micro-electromechanical systems (MEMS) and microfluidics. In addition, I also lectured on microfluidics and micro and nanofabrication techniques to engineering students

What are the main challenges in integrating micro and nanotechnologies, and how do you address them in your research?

Integration refers to the combination, whether electrical or/and mechanical, of different devices and structures to achieve a compact system with a useful function. The aim is to preserve the unique properties of micro and nanoscale structures as they are incorporated into larger final objects. In this topic there are a broad range of challenges.

In the investigations that I have been working on, a challenge in integrating micro and nanotechnologies lies on the wafer level manufacturing, in combining different and compatible fabrication processes. For instance, in some fabrication processes, it is often necessary to pattern structures having different sizes in various fabrication steps and consequently, this implies writing a pattern on top of another that is already fabricated, which increases the price and time of the process. One approach that I have been researching rely on developing nanoimprint lithography processes for the creation of these patterns in a single and fast fabrication step, which results in lowering the cost and increasing the throughput of the wafer manufacturing. In addition, for producing devices in which optical assess is a requirement, such as those for applications as photonics or microfluidics, it is necessary to use transparent materials like glass or transparent polymers and the patterning of these materials can be a challenge. A way to address this relies on developing replication techniques from silicon to polymers using also nanoimprint lithography for the patterning.

Integrating micro and nanotechnologies also involves interfacing with the human body. This can include applications as wearable devices, with micro and nanoscale sensors for wearable health monitoring that track vital signs and other health metrics continuously. Regarding this field, I have been working on the integration of printed temperature sensors on textiles for health monitoring. In this case, the main challenges are printing in a rough surface, and having a flexible sensor which is not affected by mechanical deformation. To overcome these problems, we also integrate polymer layers on the surface of the textile.  Coating the textile helps to reduce surface roughness. Producing the sensor in a polymer, which is flexible and not stretchable, and which can be bonded to the textile, provides stability and reduces mechanical deformation issues. This topic also involves challenges such as ensuring durability, washability, and comfort, as well as integrating power sources and data transmission capabilities, which we are still working on.

Can you share an example of how your work has been or could be applied to solve real-world problems?

One example relies on the development of surface nano-structures, which can be used for multiple purposes: i) they can be used in reducing the reflection and improving the transmission of light in a surface, at wide angles of incidence and broad wavelength range, which are key parameters in the performance of optical devices, such as lenses and displays. These nano-structures can also be used in photovoltaics to increase absorption for improving solar cells’ performance and therefore achieving more efficiency in the transformation of solar energy into electricity. 

ii) the presence of microstructures and nanostructures in the surface of materials, alone or combined as hierarchal structures,  can also be used for controlling surface wettability, with wettability being the ability of liquids to keep in contact with solid surfaces. In this context, the structures can be used for creating self-cleaning or superhydrophobic surfaces, in which the surface is able to clean itself when water is present. This is particularly relevant for objects in which a surface is exposed to any dirt or bacteria.

How do you communicate the complexities of your work to non-experts or the general public? Are you involved in any educational initiatives to promote micro and nanotechnology?

I participated in the European researcher’s night and have been participating every year in an initiative at my son’s school about the parents’ job by explaining to children in primary school what is nanotechnology and how nanotechnology can be used in order to help society by providing examples of applications. It is interesting to let them know that nanotechnology is an exciting and fast-moving area in science with a myriad of applications such as medicine, electronics, energy, food safety and environment, among many others. It is very fascinating to explain kids that nanotechnology is beyond what is visible by comparing a nanometer with the size of daily objects, as a soccer ball, a hair or the human blood cells.

Patrícia’s insights remind us that the future of technology relies not only on groundbreaking research but also on engaging the next generation and fostering a broader understanding of science’s role in shaping a sustainable, high-tech world.

Text and Photography by Gina Palha, Communication, Conferences & Marketing Officer