Nitrogen evolution from copper nitride films by MeV ion impact

Abstract

Copper nitride thin films deposited by the rf reactive sputtering technique at three different substrate temperatures are irradiated by 200 MeV Au¹⁵⁺ ions. The on-line fluence dependent elastic recoil detection analysis (ERDA) study shows loss (>400 atoms/ion) of nitrogen from the films. The depletion rate of N is quite high as compared to sputtering rate normally observed in the regime of elastic collisions. This is attributed to the electronically mediated energy loss (S_e) which in this case is dominant as compared to the energy loss due to nuclear collisions (S_n). The aspects based on the physical properties of the films (surface morphology and crystallinity) that play an important role in enhancing the coupling of the energy of incident ions to the lattice atoms, causing atomic ejection are discussed. Crystallinity and surface morphology of the films are studied by the grazing angle X-ray diffraction (GAXRD) and the atomic force microscopy (AFM) techniques.

Key Words:

• Copper nitride
• Reactive sputtering
• Grazing angle X-ray diffraction
• Grain size
• Elastic recoil detection analysis

PACS Codes:

• 81.15.cd
• 68.55.Jk
• 68.55.nq