Platinum and palladium oxalates: positive-tone extreme ultraviolet resists

Miriam Sortland; Jodi Hotalen; Ryan Del Re; James Passarelli; Michael Murphy; Tero S. Kulmala; Yasin Ekinci; Mark Neisser; Daniel A. Freedman; Robert L. Brainard

doi:10.1117/1.JMM.14.4.043511

Translator Disclaimer

24 December 2015 Platinum and palladium oxalates: positive-tone extreme ultraviolet resists

Miriam Sortland, Jodi Hotalen, Ryan Del Re, James Passarelli, Michael Murphy, Tero S. Kulmala, Yasin Ekinci, Mark Neisser, Daniel A. Freedman, Robert L. Brainard

Author Affiliations +

J. of Micro/Nanolithography, MEMS, and MOEMS, 14(4), 043511 (2015). https://doi.org/10.1117/1.JMM.14.4.043511

Abstract

Here, we present platinum and palladium mononuclear complexes with EUV photosensitivity and lithographic performance. Many platinum and palladium complexes show little or no EUV sensitivity; however, we have found that metal carbonates and metal oxalates (L₂M(CO₃) and L₂M(C₂O₄); M=Pt or Pd) are sensitive to EUV. The metal carbonates give negative-tone behavior. The most interesting result is that the metal oxalates give the first positive-tone EUV resists based on mononuclear organometallic compounds. In particular, (dppm)Pd(C₂O₄) (dppm=1,1-bis(diphenylphosphino)methane) (23) prints 30-nm dense lines with E_size of 50 mJ/cm². Derivatives of (23) were synthesized to explore the relationship between the core metal and the resist sensitivity. The study showed that palladium-based resists are more sensitive than platinum-based resists. The photoreaction has been investigated for two of our most promising resists, (dppm)Pd(C₂O₄) (23) and (Ph₂EtP)₂PdC₂O₄ (27). Our experiments suggest the loss of CO₂ and the formation of a zerovalent L₄Pd complex upon exposure to light. We have identified dppm₂Pd(δ(P)23.6) as the main photoproduct for (23) and (Ph₂EtP)₄Pd (δ(P)32.7) as the main photoproduct for (27).

Citation Download Citation

Miriam Sortland, Jodi Hotalen, Ryan Del Re, James Passarelli, Michael Murphy, Tero S. Kulmala, Yasin Ekinci, Mark Neisser, Daniel A. Freedman, and Robert L. Brainard "Platinum and palladium oxalates: positive-tone extreme ultraviolet resists," Journal of Micro/Nanolithography, MEMS, and MOEMS 14(4), 043511 (24 December 2015). https://doi.org/10.1117/1.JMM.14.4.043511

Published: 24 December 2015

ACCESS THE FULL ARTICLE