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:2026/phd-defence-m-illienko@8F96275E-9F55-4B3F-A143-836282E12573 CREATED:20260525T160126 LOCATION:(1st floor) Auditorium, Main building De Boelelaan 1105 1081 HV Amsterdam SUMMARY:PhD defence M. Illienko X-ALT-DESC;FMTTYPE=text/html:

Picosecond Ultrasonics for Nanoscale Subsurface Structural Characterization

Seeing t hrough metal with sound: new laser technique reveals hidden nanostruc tures

The research focuses on so-called picosecond u ltrasound, a form of hypersound in which extremely high-frequency sou nd waves are generated by ultrafast lasers. Whereas light is often bl ocked by materials such as metal, sound waves can travel through them . That principle forms the basis of the new imaging technique.

Illienko succeeded in detecting and characterizing nanostructures und er layers of metal. These structures are smaller than a hundredth of the thickness of a human hair and so small that conventional light ca nnot distinguish them. According to him, this opens up new possibilit ies for investigating objects that until now have remained hidden fro m existing measurement methods.

In addition to the practical de monstration, Illienko also investigated exactly how hypersound is gen erated and measured with ultrafast lasers. That process proved comple x, but a better understanding of it could lead to faster and more acc urate 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 i nto limits in this regard because light has difficulty penetrating op aque materials. Instead, the new method uses sound waves, which can p enetrate deeper. As a result, the technology could help inspect the n ext generation of semiconductors and electronic components in the fut ure.

According to Illienko, the technology ultimately offers th e prospect of more efficient quality control, more reliable chips and further miniaturization of electronics.

Learn more about the < a href="https://hdl.handle.net/1871.1/aa55bbc1-916a-467d-807f-a44ba7a 50411" data-new-window="true" target="_blank" rel="noopener noreferre r">thesis

DESCRIPTION:

Seeing through metal with sound: new laser technique reveals hidden nanostructures

Physicist Maksym Illienko develope d a new technique that can reveal hidden nanostructures using sound w aves and ultrafast lasers. The method makes it possible to detect ext remely small structures under opaque materials - even when they remai n invisible with ordinary microscopes. The research focuses on so-cal led picosecond ultrasound, a form of hypersound in which extremely hi gh-frequency sound waves are generated by ultrafast lasers. Whereas l ight is often blocked by materials such as metal, sound waves can tra vel through them. That principle forms the basis of the new imaging t echnique. Illienko succeeded in detecting and characterizing nanostru ctures under layers of metal. These structures are smaller than a hun dredth of the thickness of a human hair and so small that conventiona l light cannot distinguish them. According to him, this opens up new possibilities for investigating objects that until now have remained hidden from existing measurement methods. In addition to the practica l demonstration, Illienko also investigated exactly how hypersound is generated and measured with ultrafast lasers. That process proved co mplex, but a better understanding of it could lead to faster and more accurate measurements at the nanoscale. The results are of interest to the semiconductor industry. Manufacturers of chips for smartphones , computers and other electronic devices must constantly verify that the internal structures of chips are built correctly during the manuf acturing process. As chips become smaller and more complex, so does t he need for techniques that can look below the surface without damagi ng the material. Traditional optical inspection methods run into limi ts in this regard because light has difficulty penetrating opaque mat erials. Instead, the new method uses sound waves, which can penetrate deeper. As a result, the technology could help inspect the next gene ration 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 Picose cond Ultrasonics for Nanoscale Subsurface Structural Characterization END:VEVENT END:VCALENDAR