High-aspect-ratio germanium zone plates fabricated by ractive ion etching in chlorine
2009 (English)In: Journal of Vacuum Science & Technology B, ISSN 1071-1023, E-ISSN 1520-8567, Vol. 27, no 2, L1-L3 p.Article in journal (Refereed) Published
This article describes the fabrication of soft x-ray germanium zone plates with a process based on reactive ion etching (RIE) in Cl-2. A high degree of anisotropy is achieved by sidewall passivation through cyclic exposure to air. This enables structuring of higher aspect ratios than with earlier reported fabrication processes for germanium zone plates. The results include a zone plate with a 30 nm outermost zone width and a germanium thickness of 310 tun having a first-order diffraction efficiency of 70% of the theoretical value. 25 nm half-pitch gratings were also etched into 310 nut of germanium. Compared to the electroplating process for the commonly used nickel zone plates, the RIE process with Cl-2, for germanium is a major improvement in terms of process reproducibility.
Place, publisher, year, edition, pages
2009. Vol. 27, no 2, L1-L3 p.
x-ray optics; nickel; ti
IdentifiersURN: urn:nbn:se:kth:diva-9806DOI: 10.1116/1.3089371ISI: 000265839400001ScopusID: 2-s2.0-64549134292OAI: oai:DiVA.org:kth-9806DiVA: diva2:133127
QC 201007282009-01-072009-01-072011-11-14Bibliographically approved