Electronics Weekly
Sara Pellegrini is based in Edinburgh, her home since she arrived at Heriot-Watt University as part of a PhD project in SPAD (single photon avalanche diodes). She is responsible for the full technology development of SPAD pixels from initial concept to full industrialisation and for research collaboration in the UK.
Having gained a degree in electronics engineering at Politecnico di Milano, she took the opportunity to go abroad and did a final year project at the university through an Erasmus collaboration. “Afterward, I was asked to stay at Heriot-Watt for a PhD continuing to collaborate with Politecnico di Milano and I accepted. It was one of the best experiences in my life, as moving to a different country opens the mind,” she recalls.
She believes students need to seize all opportunities while they are studying, and says these years are a time of true freedom. “During this period, it is vital that they create the network that will be part of their assets as their career progresses,” she says.
Continued learning
The choice of degree subject came about because she was fascinated with uncovering the secrets of electronics. “I was mesmerised by seeing all of the elements mounted on the PCB inside an amplifier. Today this path is blocked by all electronics being hidden away behind shiny screens or black cases, so it is important that we try and break the box to show young people what’s inside,” she explains.
During her PhD she worked on the design and characterisation of SPADs, with a salary through EQUIS, the European Commission’s research programme to develop technologies for photon-based quantum processing and communication systems. Both elements are still integral parts of her current role at ST. “I use the knowledge developed during my PhD to ensure we adopt all the relevant design, process, and characterisation steps to achieve successful devices,” she adds.
Pellegrini is still interested in education and manages relationships with local universities. ST funds PhD students in several Scottish universities, she says, and hosts internships for undergraduate students from all over the UK. In 2022 there were 16 students in an office of 130 employees. “As part of our collaboration with universities, we give regular talks to engage with students and make them appreciate what career opportunities are there. We also take part in the Industrial Advisory boards for all university courses we work with to ensure that the curriculum remains relevant to our needs.”
Schools and STEM
She is also keen to encourage students of all ages to engage in STEM subjects. The company takes part in local outreach activities in Edinburgh’s primary and high schools. One programme of note is the Silver Industrial Cadets scheme, says Pellegrini, in which ST’s STEM volunteers helped five students design and assemble an LED electronics circuit, program it and characterise its properties.
The company also regularly engages with the local STEM hub, taking part in local STEM activities including speed networking for career talks. Together with some colleagues, Pellegrini designed a 50-minute workshop for primary schools. The children build an electric circuit using snap electronics and then play with some of ST’s time-of-flight sensors. “Letting 10-year-olds play with electronics is the best way to start breaking down the barriers that prevent children from considering a STEM career. Reinforcing this by having activities in high schools is key to encouraging potential new electronics engineers,” she says.
“Unfortunately, because computer science is a very easy and affordable path to take (as they need only a tablet and some programming skills to create a new app) many talented students take this path. It is much more challenging to enable photonics labs in schools, as they require more funding and dedicated knowledge.
“At ST, we strive to deploy a wider use and understanding of time-of-flight sensors by engaging with a local body, UKESF [UK Electronic Skills Foundation], to develop an affordable measuring system for schools.”
Given the chance, she would invite a diverse group of engineers and other professionals to go to primary schools and show the students what it is like to play with electronics inside the products they are already using “and show them all the cool things you can do with it”.
Pellegrini believes sensors will continue to play an important role in the next generation of consumer devices, the IoT and security. She believes this will drive the development of more efficient devices, both in terms of power consumption and usability. “In parallel, we are developing better devices such as SPADs, photodiodes or transistors that can operate with higher efficiency at lower voltages, and we’re working on more efficient signal processing using neural networks and machine learning.”
