Moore’s law
Moore’s law states that every two years, our computer chips double their amount of transistors.. To keep up with this law, scientists and engineers face increasingly more challenges as sizes get ever smaller. Currently they are confronted with the task to produce chips with transistors smaller than 13 nanometer. For this, they will need to re-invent their technology. On a two-day conference in Amsterdam, organized by scientists from ARCNL and Leiden University, physicists and chemists from around the world got together to discuss their progress.

Imprint
Chips are produced in a similar way to how photographs used to be made. A mask ensures that light illuminates certain areas of a photosensitive material, causing local chemical changes there. This way, the mask imprints a desired structure onto the material. The smaller the light’s wavelength, the more accurate this imprint will be, eventually allowing for smaller transistors.

Extreme ultraviolet
For the next generation transistors, industry needs to find ways to actually use smaller wavelengths. Billions of euros are currently invested in a technique with 13-nanometer light (92 eV), called extreme ultraviolet (EUV). This huge sum is needed because EUV requires new technology on many different levels. We know little about how the photosensitive material responds to EUV light. For example, the light will generate an electron cloud inside the material that may blur the detailed imprint.

Electron cloud
Leiden physicist Sense Jan van der Molen gave an invited talk at the LEELIS conference on his research on electron clouds. Together with Aniket Thete (ARCNL/Uni Leiden) and Ruud Tromp (IBM/Uni Leiden), he studies electrons of varying energy and looks at the impact they have on photosensitive material. Thus they can pinpoint exactly for which electron energy the imprint gets blurred. Such data are crucial for the progress of EUV-lithography as the chip-defining technique of the future.

The conference on Low-energy electrons: Lithography, Imaging and Soft Matter (LEELIS) is organized by the Advanced Research Center for Nanolithography, an institute founded by ASML and FOM.