Scientists from the University of California (Santa Barbara) have discovered a quantum mechanism that explains how a single electron can cause damage inside silicon chips, which over time leads to a decline in device performance.
Modern electronic devices, from smartphones to laptop computers and medical systems, rely on the stability of semiconductors over long periods of time. However, even the most advanced chips degrade over time, and one of the main causes of that process is the phenomenon known as “hot-carrier” degradation.
Quantum mechanics reveals how a single electron damages a chip
Until now, it was thought that damage occurs as a consequence of the cumulative action of a large number of electrons. However, new research shows that only one high-energy electron is enough to start the process of breaking the chemical bonds inside the transistor.
The key focus of the research was on the bond between silicon and hydrogen, which is located at the silicon-oxide interface. During manufacturing, hydrogen is used to prevent defects and their impact on chip operation. However, under the influence of electrons, hydrogen can dissociate, reactivating defects and starting to degrade performance.
A new quantum model shows that a single electron, when it occupies a specific energy state, can weaken this bond and trigger the separation of the hydrogen atom. Additionally, it was found that hydrogen does not behave like a classical particle, but like a wave, which means that the process cannot be described by simple physical parameters, but by the probability of a quantum state.
This discovery explains the previously unclear results of the experiments, including the fact that the damage is most pronounced at certain electron energy levels, as well as why replacing hydrogen with the heavier isotope deuterium significantly slows the degradation.
The importance of this research goes beyond classic silicon chips, because similar processes occur in other semiconductor materials, including those used in LED technology and energy systems.
The discovery opens up the possibility of developing new materials more resistant to degradation, which in the future could extend the working life of electronic devices and improve their reliability, writes Phys.Org.