Researcher Francesc Pérez Murano joins the Reial Acadèmia de Ciències i Arts de Barcelona

Francesc Pérez Murano, researcher at the Institute of Microelectronics of Barcelona in the NEMS and Nanofabrication Group (NANONEMS), enters today as a full member of the Reial Acadèmia de Ciències i Arts de Barcelona. Pérez Murano will have his reception session at 6 p.m. at the Academy's headquarters (Rambla 118, Barcelona) and will be answered by the numerary academician H.E. Mr. Xavier Obradors i Berenguer (ICMAB-CSIC).

La Nanoelectrònica: la filla més quàntica de l’Electrònica

Nanoelectronics is a branch of electronics -and, therefore, of physics- and, as such, its object of study is the transport of electrons. The functional elements of electronics are the devices, by means of which we control the transport of electrons. Devices are responsible for incorporating the basic functions of processing, storing and transmitting electrical signals, i.e. the practical application of electronics. Nanoelectronics focuses on electronic devices, the dimension of which is in the nanometer range, typically, for dimensions below 100 nanometers.

Nanoelectronics originated as a need to find solutions to the limitations that microelectronics was expected to have in its evolution towards smaller and smaller dimensions. Even so, nanometric measurement devices are also the object of study in microelectronics. However, nanoelectronics focuses on those aspects that make nanometric measurement give rise to a particular and differentiated phenomenology. The physics of very small objects is dominated by quantum physics. In nanoelectronics, quantum effects manifest themselves in an exceptional way.

The miniaturization of electronic devices and, in particular, solid-state devices, has led in a natural way to nanoelectronics. In fact, the understanding of the phenomenology of electron transport in a solid did not come about until the quantum mechanical formulism was applied in the late 1920s. Therefore, implicitly, at that time one could already speak of nanoelectronics. However, the term nanoelectronics was not explicitly used until 1987, in a research program at Texas Instruments. The aim of the program was to develop a new technology that would allow the reduction of device dimensions in integrated circuits beyond the limits of conventional technology that were already foreseen at that time. Research focused on the theoretical and experimental investigation of resonant tunnel diodes and, in particular, on how the reduction of the lateral dimensions of the devices makes it possible to achieve quantum confinement of electrons in three dimensions.

Thus, in the 1980s, the two aspects that characterize nanoelectronics were already present: the continuous reduction of the dimensions of integrated circuits (and, in particular, of field-effect transistors as the key device that makes this reduction possible) and the search for alternative devices that, based on quantum phenomena, would allow a continuous increase in the performance of electronic systems.

In the first area, based on silicon and integrated circuits, nanoelectronics goes hand in hand with microelectronics. The extraordinary evolution of integrated circuit manufacturing technology since the invention of the transistor in 1947 has made it possible to industrially manufacture chips with transistors whose dimensions are close to 10 nanometers. The new types of field-effect transistors being developed in this century, starting with FINFET transistors, make it possible to fit more and more transistors into integrated circuits, making Moore's law still valid. This report reviews how these transistors are now used both for logic applications (microprocessors) and for memories. In this field, nanoelectronics has, therefore, a huge impact on society, since it enables all the applications we know based on digital information processing.

In the second aspect, nanoelectronics proposes new devices that allow a different control of electron transport from the classical one. In the case of collective electron transport control, we find approaches such as spintronics, which, instead of manipulating electric charge, focuses on electron spin, and memoresistances, devices that can give rise to neuromorphic computing, of great interest, for example, for artificial intelligence.

Nanoelectronics shows its full potential in the ability to control the transport of a single electron. In addition to the possibility of achieving circuits that consume very little energy, the control and manipulation of a single electron, and the spin of this electron, opens the door for semiconductors towards quantum technologies. In recent years, qubits based on semiconductor quantum dots have experienced a very important advance, and are presented as the most promising technology, due to their scalability, and to be able to have, in the future, quantum computers that, by means of a fairly large number of qubits, can solve practical problems that are unmanageable for traditional computers.

Undoubtedly, electronics - and therefore nanoelectronics - will continue to be present in our lives, at least as long as mankind is capable of producing the energy needed to manage the transport of electrons. Its current impact on society can only increase, bearing in mind that the continuous evolution of electronic devices and circuits will make it possible to increase their performance as technology improves and new concepts are introduced. The areas expected to have the greatest impact will be information processing, storage and transmission, quantum technologies, sensor technology and biomedicine, and in each case energy management will improve. Even so, their evolution will not be exempt from the challenges that humanity has to face, including lack of resources and sustainability, training and education, democratization, security and responsibility.

The exhibition La revolució silenciosa, which traces the history of the transistor up to the present day, can be visited at RACAB these days.