Self-formation of dielectric layer containing CoSi₂ nanocrystals by plasma-enhanced atomic layer deposition

Dielectric layer containing CoSi₂ nanocrystals was directly fabricated by plasma-enhanced atomic layer deposition using CoCp₂ and NH₃ plasma mixed with SiH₄ without annealing process. Synchrotron radiation X-ray diffraction and X-ray photoelectron spectroscopy results confirmed the formation of CoSi₂ nanocrystal. The gate stack composed of dielectric layer containing CoSi₂ nanocrystals with ALD HfO₂ capping layer together with Ru metal gate was analyzed by capacitancevoltage (CV) measurement. Large hysteresis of CV curves indicated charge trap effects of CoSi₂ nanocrystals. The current process provides simple route for the fabrication of nanocrystal memory compatible with the current Si device unit processes.