High diffraction-efficiency molybdenum gratings for EUV lithography

✍ Scribed by Menouer Saidani; Harun H. Solak

• Book ID: 104052287
• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 425 KB
• Volume: 86
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/j.mee.2009.02.019

✦ Synopsis

Two generations of transmission molybdenum gratings are realized; the first one made with laser interference lithography (LIL) has 300 nm period and the second one made with extreme UV interference lithography (EUV-IL) using the first one has 150 nm period. This technique is a good alternative to e-beam lithography which inevitably introduces field-stitching errors into the gratings. The idea is to produce a first defect-free grating using LIL and to realize higher resolution gratings by multiplying the frequency of this first grating using EUV-IL. Measurements over a wavelength range that includes the industry standard 13.5 nm show the attainment of diffraction efficiency close to the theoretically expected value of 29% for these phase-gratings.