Atomic Layer Deposition and Properties of Lanthanum Oxide and Lanthanum‐Aluminum Oxide Films

Abstract

Abstract Atomic layer deposition (ALD) of lanthanum oxide on glass and silicon substrates was examined using lanthanum silylamide, La[N(SiMe 3 ) 2 ] 3 , and water as precursors in the substrate temperature range of 150–250 °C. The effect of pulse times and precursor evaporation temperature on the growth rate and refractive index was investigated. The films remained amorphous regardless of the deposition conditions. The resulting La 2 O 3 films contained noticeable amounts of hydrogen and silicon and were chemically unstable while stored in ambient air. Lanthanum aluminum oxide films were achieved with stoichiometry close to that of LaAlO 3 at 225 °C from La[N(SiMe 3 ) 2 ] 3 , Al(CH 3 ) 3 , and H 2 O. The lanthanum β‐diketonate precursor, La(thd) 3 , was used as the reference precursor.