Evaluation of New Aminoalkoxide Precursors for Atomic Layer Deposition. Growth of Zirconium Dioxide Thin Films and Reaction Mechanism Studies

Atomic layer deposition (ALD) was used for growing zirconium dioxide (ZrO 2 ) thin films by alternate surface reactions between new aminoalkoxides and water. The zirconium aminoalkoxide precursors were Zr(dmae) 4, Zr(dmae) 2 (O t Bu) 2, and Zr(dmae) 2 (O i Pr) 2 (dmae is dimethylaminoethoxide, [OCH 2 CH 2 N(CH 3 ) 2 ]). Films were deposited on soda and borosilicate glass at 190−340 °C. The growth rate increased with elongated Zr precursor pulse possibly due to precursor decomposition. The as-deposited films contained substantial amounts of residual hydrogen. Reaction mechanisms were studied with a quadrupole mass spectrometer (QMS) and a quartz crystal microbalance (QCM) connected to the ALD reactor. The QMS results showed that the precursors decompose at higher temperatures, Zr(dmae) 4 making an exception. According to the QCM results, all precursors start to decompose with longer Zr precursor pulses.