Highly Anisotropic and Corrosionless PtMn Etching using Pulse-Time-Modulated Chlorine Plasma

Seiji Samukawa, Shinya Kumagai, Toshiaki Shiraiwa

Research output: Contribution to journalArticlepeer-review

9 Citations (Scopus)


Thin PtMn films have recently been used in magnetic devices such as magnetoresistive random access memories (MRAMs). A general problem with this material is that it is relatively inert during conventional plasma processes, and thus alternative methods such as ion milling, lift-off and electroplating have been employed for pattern transfer. As the density of magnetic memories increases toward the Gbit range, the film must be patterned at sub-micron widths. To achieve this requirement, we propose pulse-time-modulated plasma etching. We found that highly anisotropic PtMn etching could be achieved with smooth and corrosionless sidewalls using pulse-time-modulated (TM) chlorine plasma at a pulse time of 10 to 100μs. We concluded that the incident Cl - could enhance the chemical reaction on the PtMn surface.

Original languageEnglish
Pages (from-to)L1272-L1274
JournalJapanese Journal of Applied Physics, Part 2: Letters
Issue number10 B
Publication statusPublished - 2003 Oct 15


  • Magnetoresistive random access memories (MRAMs)
  • Negative ions
  • PtMn
  • Pulse-time-modulated plasma
  • Reactive ion etching (RIE)
  • Spin valve materials

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)


Dive into the research topics of 'Highly Anisotropic and Corrosionless PtMn Etching using Pulse-Time-Modulated Chlorine Plasma'. Together they form a unique fingerprint.

Cite this