{"id":766,"date":"2026-06-21T04:25:49","date_gmt":"2026-06-21T04:25:49","guid":{"rendered":"https:\/\/saiht.de\/blog\/?p=766"},"modified":"2026-06-27T06:46:47","modified_gmt":"2026-06-27T06:46:47","slug":"duv-vuv-euv","status":"publish","type":"post","link":"https:\/\/saiht.de\/blog\/2026\/06\/21\/duv-vuv-euv\/","title":{"rendered":"DUV – VUV – EUV"},"content":{"rendered":"\n

In recent years the industry related to computers and the internet has become a larger part of the economy and everyday life of humans. The computational<\/strong> parts are found in smartphones, cars, bank terminals, TVs, coffee machines and toasters. The smaller the structure, the more energy efficient it can be, the faster it can compute, the more integrated it can get.<\/p>\n\n\n\n

Light sources<\/p>\n\n\n\n

The smallest feature size is related to the light source used. One can get beyond the Rayleigh limit<\/a> with multi-pattern, phase corrected images etc. But eventually one needs a shorter wavelength. The limit of DUV<\/strong> (deep ultra violet 193nm) was long known. Since the 1990s serious investigations have been made to go beyond. Eventually EUV<\/strong> (extreme ultra violet 13.5nm) emerged as the solution, and in 2026 the company ASML<\/strong> is the sole provider of light sources with this wavelength for large scale lithography to produce semiconductors. A “simple machine” costs easily 180,000,000 USD like the TWINSCAN NXE:3300B that first shipped 2013.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

And the high-NA rather approach 400 million USD. My AR65 machine 6 years earlier at the Humboldt university in Berlin was not that expensive. Here at BESSY:<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

But I wondered what wavelength I was using to investigate my CdHgTe crystals. In the early 2000s we labeled our light as VUV<\/strong> (vacuum ultra violet) because for the energy used there is no window material available (6.2 to 124 eV, see my diploma thesis<\/a> from 2008, page 19). We measured the energy in eV because the energy itself was more important. The conversion is easy:<\/p>\n\n\n\n

E<\/mi>=<\/mo>h<\/mi>v<\/mi><\/mrow>\u03bb<\/mi><\/mfrac><\/mrow>E = \\frac{hv}{\\lambda}<\/annotation><\/semantics><\/math><\/p>\n\n\n\n

where:<\/p>\n\n\n\n

    \n
  • c<\/mi>=<\/mo>2.99792458<\/mn>\u00d7<\/mo>10<\/mn>8<\/mn><\/msup>\u2009<\/mtext>m\/s<\/mtext><\/mrow>c = 2.99792458 \\times 10^8\\,\\text{m\/s}<\/annotation><\/semantics><\/math> (speed of light).<\/li>\n\n\n\n
  • h<\/mi>=<\/mo>6.62607015<\/mn>\u00d7<\/mo>10<\/mn>\u2212<\/mo>34<\/mn><\/mrow><\/msup>\u2009<\/mtext>J\u00b7s<\/mtext><\/mrow><\/mrow><\/semantics><\/math> (Planck’s constant),<\/li>\n<\/ul>\n\n\n\n

    With the Bessy Syncrotron I used the beam energy up to 125 eV, the respective wavelength is \u03bb<\/mi>\u2248<\/mo>9.92<\/mn>n<\/mi>m<\/mi><\/mrow>\\lambda \\approx 9.92 nm<\/annotation><\/semantics><\/math> is actually shorter<\/strong> than the 13.5 nm (92 eV) used by ASML<\/p>\n\n\n\n
    \"\"<\/figure>\n\n\n\n

    But for most cases I needed less energy, the lower energy bands were more important for the optical and electronical properties of my narrow-gap semiconductor. Most measurements were actually done with the He I \u03b1<\/strong> line at 21.218 eV or 58.43 nm<\/strong>. That is significanly shorter than DUV, the shortest wavelength currently used for lithography in China with the Argon fluoride excimer laser ArF and 193 nm (6.42 eV). With immersion scanners (ArFi) one can achieve a high numerical aperture up to 1.35 and produce chips at nominal 7 nm. A great example of engineering achievements. <\/p>\n\n\n\n

    Name<\/th>Source<\/th>Wavelength<\/th>Photon energy<\/th><\/tr><\/thead>
    VUV<\/td>Syncrotron<\/td>9.9 nm<\/td>125 eV<\/td><\/tr>
    EUV<\/td>Sn<\/td>13.5 nm<\/td>91.8 eV<\/td><\/tr>
    VUV<\/td>He I \u03b1<\/td>58.4 nm<\/td>21.22 eV<\/td><\/tr>
    DUV<\/td>ArF<\/td>193 nm<\/td>6.42 eV<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

    <\/p>\n","protected":false},"excerpt":{"rendered":"

    In recent years the industry related to computers and the internet has become a larger part of the economy and everyday life of humans. The computational parts are found in smartphones, cars, bank terminals, TVs, coffee machines and toasters. The smaller the structure, the more energy efficient it can be, the faster it can compute, […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[9,42],"tags":[],"class_list":["post-766","post","type-post","status-publish","format-standard","hentry","category-projects","category-study"],"acf":[],"_links":{"self":[{"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/posts\/766","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/comments?post=766"}],"version-history":[{"count":9,"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/posts\/766\/revisions"}],"predecessor-version":[{"id":788,"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/posts\/766\/revisions\/788"}],"wp:attachment":[{"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/media?parent=766"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/categories?post=766"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/saiht.de\/blog\/wp-json\/wp\/v2\/tags?post=766"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}