BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Vrije Universiteit Amsterdam//NONSGML v1.0//EN NAME:PhD defence M. Illienko METHOD:PUBLISH BEGIN:VEVENT DTSTART:20260608T114500 DTEND:20260608T131500 DTSTAMP:20260608T114500 UID:phd-defence-m-illienko@8F96275E-9F55-4B3F-A143-836282E12573 CREATED:20260924T233651 LOCATION: SUMMARY:PhD defence M. Illienko X-ALT-DESC;FMTTYPE=text/html:

Picosecond Ultrasoni cs for Nanoscale Subsurface Structural Characterization

S eeing through metal with sound: new laser technique reveals hidden na nostructures

The research focuses on so-called picos econd ultrasound, a form of hypersound in which extremely high-freque ncy sound waves are generated by ultrafast lasers. Whereas light is o ften blocked by materials such as metal, sound waves can travel throu gh them. That principle forms the basis of the new imaging technique.

Illienko succeeded in detecting and characterizing nanostructu res under layers of metal. These structures are smaller than a hundre dth of the thickness of a human hair and so small that conventional l ight cannot distinguish them. According to him, this opens up new pos sibilities for investigating objects that until now have remained hid den from existing measurement methods.

In addition to the pract ical demonstration, Illienko also investigated exactly how hypersound is generated and measured with ultrafast lasers. That process proved complex, but a better understanding of it could lead to faster and m ore accurate measurements at the nanoscale.

The results are of interest to the semiconductor industry. Manufacturers of chips for sm artphones, computers and other electronic devices must constantly ver ify that the internal structures of chips are built correctly during the manufacturing process. As chips become smaller and more complex, so does the need for techniques that can look below the surface witho ut damaging the material.

Traditional optical inspection method s run into limits in this regard because light has difficulty penetra ting opaque materials. Instead, the new method uses sound waves, whic h can penetrate deeper. As a result, the technology could help inspec t the next generation of semiconductors and electronic components in the future.

According to Illienko, the technology ultimately of fers the prospect of more efficient quality control, more reliable ch ips and further miniaturization of electronics.

Learn more abou t the thesis

DESCRIPTION: Picosecond Ultrasonics for Nanoscale Subsurface Structura l Characterization

Seeing through metal with sound: new laser tec hnique reveals hidden nanostructures

Physicist Maksym Illienko de veloped a new technique that can reveal hidden nanostructures using s ound waves and ultrafast lasers. The method makes it possible to dete ct extremely small structures under opaque materials - even when they remain invisible with ordinary microscopes.The research focuses on s o-called picosecond ultrasound, a form of hypersound in which extreme ly high-frequency sound waves are generated by ultrafast lasers. Wher eas light is often blocked by materials such as metal, sound waves ca n travel through them. That principle forms the basis of the new imag ing technique.Illienko succeeded in detecting and characterizing nano structures under layers of metal. These structures are smaller than a hundredth of the thickness of a human hair and so small that convent ional light cannot distinguish them. According to him, this opens up new possibilities for investigating objects that until now have remai ned hidden from existing measurement methods.In addition to the pract ical demonstration, Illienko also investigated exactly how hypersound is generated and measured with ultrafast lasers. That process proved complex, but a better understanding of it could lead to faster and m ore accurate measurements at the nanoscale.The results are of interes t to the semiconductor industry. Manufacturers of chips for smartphon es, computers and other electronic devices must constantly verify tha t the internal structures of chips are built correctly during the man ufacturing process. As chips become smaller and more complex, so does the need for techniques that can look below the surface without dama ging the material.Traditional optical inspection methods run into lim its in this regard because light has difficulty penetrating opaque ma terials. Instead, the new method uses sound waves, which can penetrat e deeper. As a result, the technology could help inspect the next gen eration of semiconductors and electronic components in the future.Acc ording to Illienko, the technology ultimately offers the prospect of more efficient quality control, more reliable chips and further minia turization of electronics.Learn more about the thesis END:VEVENT END:VCALENDAR