Annual Report 2024

The ALCHEMY laboratory seeks to integrate chemistry, materials science, and advanced manufacturing to design functional materials with customized form and function. One of the laboratory’s main missions is to develop advanced materials for everyone; to this end, the laboratory is interested in developing accessible chemistries and processing strategies that enable the manufacture of all classes of materials and devices. ALCHEMY hopes to improve access to advanced materials and give the public and the scientific community as a whole the materials they need to solve their own challenges.

The laboratory’s research mission is to model and develop hardware and software systems
based on quantum devices. Particular emphasis is placed on single-photon avalanche diodes (SPADs), ultra-fast cameras, reconfigurable quantum processing and design automation techniques.

Research activities cover a wide range of fields:
• Cryogenic electronics
• SPADs in the near infrared and short-wavelength infrared
• Light detection and ranging (LiDAR)
• Super-resolution microscopy
• Super-resolution microscopy
• Positron emission tomography (PET)
• Quantum random number generation (QRNG)
• Superconducting devices

The laboratory’s teaching mission is to equip engineers and scientists with multidisciplinary knowledge of cutting-edge hardware and software systems.

The Bio/CMOS Interfaces (BCI) laboratory focuses on advanced design technologies for circuits and systems in biomedical applications. It is one of the world’s leading laboratories in the field of designing and manufacturing biosensors on chips and bio-interfaces, targeting DNA- and protein-based networks.
The laboratory’s research focuses on the development of new Bio/CMOS interfaces by integrating new and innovative nanomaterials and biomaterials into the electrochemical sensing surface.
The innovative approach proposed by this group consists of a joint design of the different layers (bio, nano, and CMOS frontend) to improve the integration of these highly heterogeneous systems and overcome the usual limitations of biosensors in terms of specificity and sensitivity.
The group is dedicated to research in bioelectronics and the biophysics of nanostructured and biostructured thin molecular films integrated on micro- and nano-fabricated silicon chips for applications in human diagnostics, remote monitoring of human metabolism, drug detection, personalized medicine, and precision medicine.

Lasers are revolutionizing our daily lives in many areas, particularly in microtechnology, where they are used in design and manufacturing and as a key component in a variety of miniaturized devices.
The Galatea laboratory focuses on the study of matter interaction and how it can be harnessed not only in microfabrication, but also to give materials new properties. The Galatea laboratory focuses on studying matter interaction and how it can be harnessed not only in the fields of microfabrication, but also to confer new and localized properties on matter. Among the topics of study are: the study of manufacturing processes that enable nanometric precision and the creation of structures smaller than the wavelength of a laser, the design of optical circuits made entirely of glass manufactured by laser and combining both active and passive functions, and finally, the study of phase changes in matter at ultra-short time scales and the associated crystallization phenomena.

The Micromechanical and Horological Design Laboratory (INSTANT-LAB), headed by Prof. Simon
Henein, brings together a dozen researchers: scientific staff, postdoctoral fellows and doctoral students. The laboratory specialises in the creation of centimetre-scale mechanisms incorporating kinematics and new technologies. The scientific approach adopted draws inspiration from numerous
fields of mechanical design, such as ancient and modern watchmaking, robotics and aerospace mechanisms. Current areas of application include mechanical watchmaking, biomedical instrumentation and precision mechanisms for metrology.
These are very similar, both in terms of technology and industrial fabric.
In addition to its fundamental and applied scientific mission, the laboratory is heavily involved in project-based teaching for EPFL students in microtechnology.

The Laboratory for Advanced Fabrication Technologies (LAFT) focuses on several highly interdisciplinary research thrusts. The first being the development and application of advanced additive fabrication techniques for realizing precision microelectronic and electromechanical systems. The second explores manufacturing for space and energy generation applications, combining additive manufacturing and nanoscale technology to produce novel chemical, electrochemical, and photoelectrochemical devices. Lastly, they focus on manufacturing for medical devices and biosystems to generate novel knowledge for non-invasive nanoscale solutions.

Through each of these thrusts, they develop new materials, tools, and processes, with a focus on a deep physical understanding. They then apply these capabilities to realize a range of systems in microelectronics, medical devices, precision electromechanical systems, wearables, and sensing and actuation.

LAI specialises in modelling and optimising the design of rotary and linear electric and piezoelectric motors and actuators, in a power range from μW to several kW. It focuses on modelling and optimising designs using deterministic or stochastic methods: sensorless solutions for BLDC motors exploiting a wide range of electromagnetic phenomena; bearingless solutions; machine learning and neural networks (deep learning, convolutional networks) and microelectromechanical systems (MEMS).
The Centre for Artificial Muscles (CAM), in cooperation with its partners in cardiac surgery (University of Bern) and reconstructive medicine (University of Zurich), is working on the development and clinical transfer of a completely new technological approach for artificial muscles in the human body. This centre is closely linked to the Laboratory for Integrated Actuators (LAI).

Other projects are being added to the heart pump: a urinary sphincter for incontinence problems, and facial reconstruction for people who have lost muscle mobility in part of their face.

Research at the Applied Mechanical Design Laboratory (LAMD) focuses on small-scale turbomachinery for decentralised energy conversion. Typical applications range from small gas turbines and compressors for domestic heat pumps to high-speed expanders for waste heat recovery using organic Rankine cycles.
Scaling laws for turbomachinery impose increasingly smaller tip diameters and higher rotational speeds, while reducing conversion powers. Consequently, the main research activities include an in-depth theoretical and experimental study of high-speed bearing technologies and their effects on rotor dynamic behaviour. Gas-lubricated dynamic bearing technologies are particularly emphasised.
In addition, the laboratory specialises in integrated mechanical design and optimisation methodologies to automate the final stages of the design process for complex systems.

The LMTM’s research activities focus on the control and design of microstructures in metals and alloys, using a combination of thermal and mechanical treatments. Microstructural changes are quantified experimentally and modelled numerically at different scales.
The phenomena studied include recrystallisation, grain growth, twinning, texture evolution, precipitation and phase transformations, and cracking.
Beyond investigating the mechanisms underlying microstructural changes and
modelling them, a systematic link is established with the properties of the material. Applications
include the forming of thin or thick metal products, powder metallurgy and additive manufacturing.

The Soft Transducers Laboratory (LMTS) develops flexible yet powerful actuators and sensors. Researchers at this unit develop artificial muscles on a millimetre scale for small mobile robots and on a metre scale to power exoskeletons and assistive devices. Their research focuses mainly on electrostatic actuation and multifunctional stretchable materials.
The LMTS’s main areas of research are:
1. Flexible robotics for fine manipulation, such as silicone-based grippers using electro-adhesion that can safely grasp delicate objects such as ripe fruit.
2. Autonomous soft machines, swimming or crawling, using miniaturised electrohydraulic actuators to move fins or legs, and equipped with an on-board electronic system for navigation.
3. Assistive exosuits, made possible by high-energy-density fluidic, phase-change and electrostatic actuators integrated into textiles.
4. Portable haptic displays for VR/AR applications and for visually impaired users.
5. Environmentally friendly MEMS processes and applications, using additive manufacturing for electronics and eco-resorbable and bioresorbable sensors.

The laboratory’s main mission is to develop the science and technology of advanced photovoltaic cells and modules. It also addresses aspects of solar integration into new energy systems, in connection with storage and electric mobility.
PV-LAB’s research activities cover a wide range of activities related to the field of photovoltaics, with a focus on advanced thin-film manufacturing processes, diffusion, oxidation, etc. The laboratory has mastered the manufacture of new silicon solar cells using passivating contacts with thin tunnel oxides or heterojunctions. The laboratory has set several records and innovations in the field of new perovskite/silicon cells, with the first certified breakthrough to over 30% in 2022. The manufacture of solar panels for building integration and mobility, performance and reliability testing of cells and
panels, analysis of electricity production from PV and its integration into the electricity grid, in conjunction with the energy system (electric mobility, heat pumps, wind power, etc.) are among the research topics.
The techniques developed for the manufacture of solar cells are also used for the development of detectors for advanced medical or optical applications.

Founded in 2018 with the support of the Werner-Siemens Foundation, the Centre for Artificial Muscles
(CAM) is dedicated to the development of implantable actuators and innovation in key areas of human health such as cardiac assistance, urology and facial paralysis. In collaboration with its partners in cardiac surgery and urology at the University of Bern and in reconstructive medicine at the University of Zurich, the CAM aspires to become a global leader in the development and clinical transfer of a new technological approach to artificial muscles for the human body.

Activities

M2C efforts are focused specifically on the latest advances in additive manufacturing and free-form technologies. They are specialized in the micro-fabrication of smart components and systems and in the processing of high-precision free-form materials, including the creation of nano and microstructures.

Objectives

MC2 fosters collaborative exchanges among academic, institutional and industrial participants by:

– offering multidisciplinary technology platforms and meeting locations to foster interactions,

– identifying and coordinating research in such fields as miniaturization; portability; integrated functionality; low energy consumption; durability; and material optimization,

– forwarding additive/advanced manufacturing technologies in ways that are economically viable and environmentally sustainable compared to traditional methods,

– ensuring that technological gains are efficiently transferred to the manufacturing companies for actual impact in the economy,

– developing training procedures and programs in connection with the doctoral school of advanced manufacturing (EDAM) to further continuing education.

Some research highlights:
1. A hydrogel matrix shaping process that allows 3D-printed hydrogels to be transformed into composites, ceramics, or metals after fabrication.
2. 3D-printable boronate ester-based elastomers with self-healing properties
3. A custom LCD printer that uses a single tank and a single resin to manufacture multiple materials;
4. 3D-printable semi-crystalline polymers that are resistant to acids and bases;
5. Photo-switchable additives

This year, CAM successfully completed its fourth series of pre-clinical tests. The first minimal cardiac assistance system is now evolving into a fully-fledged left ventricular assist device (LVAD), thanks to an innovative pre-stretching system. In the field of facial paralysis, CAM’s research has reached a decisive milestone: for the first time, artificial muscles controlled by a nerve have been implanted on the back of a rat, turning hope into reality. At the same time, advances in urology mark a key milestone: bladder cells have been implanted on a platform capable of reproducing the natural deformations of the bladder, thus integrating biology as a new fundamental axis of the centre’s developments. The CAM also manufactured its very first artificial urinary sphincter based on an ongoing assembly of the dielectric elastomer actuator (DEA) cardiac assist device.

These major advances were recognised by the Werner Siemens Foundation committees, which
honoured the CAM with a visit during this pivotal seventh year. On this occasion, the centre’s scientific staff were able to present their roadmap in detail and reaffirm their commitment to developing concrete solutions to meet patients’ needs.
The centre’s research is now entering a crucial phase: transforming the work into a medical device capable of providing long-term support to the heart. The next key step will be the launch of chronic tests within the next two years. To achieve this, CAM staff will need to optimise the device to make the surgical procedure less invasive, in particular by developing a fully integrated control system, including power supply and sensors, while ensuring reliability and biocompatibility. For patients with facial paralysis, future work will aim to refine movement control to enable true facial expressions, with more pronounced skin movements in animal models.
Biologically, future trials will seek to demonstrate genotypic changes induced by cyclic deformations on the platform. Finally, validation of the artificial sphincter will require precise characterisation of the flow inside the tubular DEA in order to provide rigorous confirmation of the approach used.

Among the highlights in 2024, the team carried out an initial demonstration of the local transformation of Tellurite glass into a semiconductor phase of tellurium. Thus, without adding any material, an insulating glass becomes conductive simply by exposure to ultra-fast laser pulses of around 100 femtoseconds. In particular, we demonstrated the photoconductive properties of these modifications, opening up new prospects in the field of energy generation and transparent “smart” surfaces that react to their environments.
Another notable development is the launch of the spin-off company “Cassio-P”, which will market miniaturised femtosecond laser sources, mainly based on micro-machined glass, the result of research carried out at the laboratory, notably as part of a project funded by the prestigious European Research Council (ERC).

Flexible pivots are widely used in precision mechanisms to eliminate friction, wear and lubrication issues associated with sliding pivots or ball bearings. However, known flexible pivots generally have the disadvantage of introducing unwanted displacement during rotation. Solutions known to date for cancelling out these undesirable parasitic translations generally result in a loss of radial rigidity, a reduction in angular travel and non-linear moment-angle characteristics. In 2024, a new family of flexible pivots called QUADRIVOT was invented and patented by INSTANT-LAB. These pivots are based on a new kinematic system with zero parasitic displacement, while mitigating the disadvantages of certain known pivot structures. Based on this invention, three symmetrical architectures were designed and implemented. The results show that these new pivots are an order of magnitude more rigid radially than known pivots, while having zero parasitic displacement properties and equivalent angular strokes. These advantages are essential for applications such as mechanical time bases for watchmaking, surgical robotics, and optomechanical mechanisms.
Prototypes made of polymer, titanium alloy and silicon for experimental validation.

In his doctoral thesis, Soheyl Massoudi advanced the design of gas-bearing turbochargers using AI and innovative optimisation methods. Taking into account real manufacturing imperfections, he developed a generic design and optimisation framework to identify efficient systems that are robust to manufacturing imperfections. His designs were tested experimentally to validate the concept of design robustness, suggesting increased tolerance ranges, which facilitates industrialisation and reduces costs. He then extended his tool to the automated CAD generation of gas-supported turbochargers to streamline the design process for complex systems. His tools and ideas promise to transform industries that use high-speed machines in heat pumps, fuel cells, and organic Rankine cycles.

The LMTM has developed a new alloy that adds aluminium to a well-known austenitic stainless steel.
When manufactured using 3D printing, this material achieves exceptional hardness values. It is also
suitable for the production of structured microstructures, optimally combining the
properties of hardness and ductility. Article here
The LMTM has developed a new hybrid additive manufacturing process combining powders and
metal sheets. This process reduces residual stresses at the interfaces between different materials, such as aluminium or titanium, and reduces the risk of cracking. Article here

The LMTS has developed a compact and versatile swimming robot capable of manoeuvring in confined spaces and carrying payloads much heavier than itself. Smaller than a credit card and weighing only 6 grams, this agile robot is ideal for environments where space for manoeuvring is limited, such as rice paddies, or for inspecting aquatic machinery.
The research was published in Science Robotics.
Unlike traditional propeller-based systems, the EPFL robot uses silent, undulating fins for propulsion, inspired by the ribbon-shaped bodies of marine flatworms. This design allows the robot to blend into the natural environment and, thanks to its light weight, float on the water’s surface like a leaf.
The robot achieves unprecedented manoeuvrability by using four artificial muscles to activate the
fins. In addition to swimming forward and turning, the robot is capable of swimming backwards and sideways – agility similar to that of a quadcopter drone, but adapted to aquatic environments.

The M2C and the site’s laboratories are continuing their efforts to strengthen equipment sharing across the Campus. With the support of the Centre for MicroNano Technology (CMI), which provides practical assistance with user management and access, several pieces of equipment from the LAFT, LAI and PV-LAB have been made available to the Campus’ scientific staff community. These devices, for which pricing is currently being finalised, are placed under the responsibility of the respective laboratory staff, acting as ‘super-users’ in charge of ensuring proper operation and training users.

Among the notable results of 2024 was a research project conducted in collaboration with the company 3S, which established a method for separating reversible parameters that cause a decline in the performance of a PV system from parameters that are intrinsic to the system and lead to its long-term degradation [1]. Also noteworthy is a predictive model of electric vehicle charging needs in 2025 [2],
the development of tandem bifacial cells (heterojunction/perovskites) deposited by a hybrid method
[3], a reduction in defects in formamidinium-rich perovskite materials and their stability [4], accompanied by several key results on this type of device [5, 6]. Also noteworthy are important articles on coloured solar modules [7], module reliability [8], more resistant tunnel oxide layers [9], and the use of detectors to measure proton beams in medical therapies [10]. More than 30 articles have been published.

1] Quest. et al. Progress in Photovoltaics: 32(11), pp. 774–789 (2024) – [2]. Jeannin et al. International Journal of Sustainable Energy Planning and Management 41, pp. 45–57 (2024) – [3] MR Golobostanfard, Nano Energy, 131, 110269 (2024) – [4] Mostafa Energy and Environmental Science , 17(11), p. 3832–3847 (2024) – [5]Turkay et al. Joule 8(6), pp. 1735–1753 2024 – [6] Kerem et al. Advanced Materials, 36(21), 2311745 (2024) –  [7] A. Borja Block et al Energy and Buildings 314, 114253 (2024), Borja Block, et al Solar Energy, 267, 112227 (2024) – [8] O. Arriga Arutti. Progress in Photovoltaics, 32(5), pp. 304–316 (2024) – [9] Libraro et al. ACS Applied Materials and Interfaces, 16(36), pp. 47931–47943 (2024) – [10] N. Wyrsch, et la, Radiation Measurements 177, 107230 (2024)