Non-destructive patterning of 10nm magnetic island array by phase transformation with low-energy proton irradiation


Dutta T., PATHAK S., ASBAHİ M., Celik K., Lee J. M., Yang P., ...Daha Fazla

APPLIED PHYSICS LETTERS, cilt.111, sa.15, 2017 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 111 Sayı: 15
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1063/1.4998670
  • Dergi Adı: APPLIED PHYSICS LETTERS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Nano-patterning on the order of sub-10 nm is integral to achieve high-density nano-scale devices for various data storage and data processing applications. However, the additional requirement of planarization and unwanted side-effects of physical or chemical etching have so far limited the patterning of sub-10nm devices. In this work, we have demonstrated the creation of an array of similar to 10nm ferromagnetic islands through selective phase transformation of paramagnetic multilayers by low-energy proton irradiation. Paramagnetic Co3O4/Pd multilayers masked with patterned PMMA (polymethyl methacrylate) were reduced to ferromagnetic Co/Pd by proton irradiation. A clear contrast of the nano-islands was observed using magnetic force microscopy, establishing the formation of ferromagnetic nano-islands with perpendicular magnetic anisotropy. This process provides a way to circumvent the side-effects associated with both conventional nano-scale pattering and high-energy ion irradiation. Therefore, phase transformation by low energy proton irradiation can be used for patterning sub-10nm nano-islands, not only for magnetic data storage but also for patterning various opto-electronic and spintronic devices. Published by AIP Publishing.