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 capacitance-voltage (C-V) measurement. Large hysteresis of C-V 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.