Low temperature chemical vapor deposition of ZrO2 on Si(100) using anhydrous zirconium(IV) nitrate

Anhydrous zirconium(IV) nitrate was used as a volatile, carbon-free precurs or for the low pressure chemical vapor deposition of thin ZrO2 films on sil icon (100) substrates. Depositions were performed at substrate temperatures between 300 and 500 degrees C at total reactor pressures between 0.25 and 1.1 Torr. During deposition the N-2 carrier gas (flow rates = 20 or 100 see m) was diverted through the precursor vessel which was maintained between 8 0 and 95 degrees C. Under these conditions typical growth rates reached 10. 0 nm/min. The polycrystalline films were predominantly monoclinic ZrO2 with compositions very near the ideal value. Cross-sectional transmission elect ron microscopy and medium energy ion scattering established that an interfa cial layer of SiO2 separates the silicon substrate from the ZrO2. Electrica l measurements made on capacitors constructed of 58 nm thick films of ZrO2 with a platinum top electrode suggest that charge trapping occurs in the Si /ZrO2 interfacial region. (C) 2000 The Electrochemical Society. S0013-4651( 00)01-089-2. All rights reserved.