Epitaxial growth of delafossite CuFeO _2 thin films by pulse laser deposition

摘要

CuFeO _2 (CFO) is a delafossite-type compound and is a well known p-type semiconductor. Epitaxial CuFeO _2 thin films were prepared on Al _2O _3 (0 0 0 1) substrates by pulsed laser deposition. The deposition, performed at 500 °C and 10 Pa leads to epitaxial phase with extremely low roughness and high density. The oxygen pressure modulates the band energy properties of Cu 2p, Fe 3p and O1s. The results show that the low deposition oxygen pressure contributes to the chemistry ingredient and magnetization properties. Furthermore, spin-glass behavior is identified and weak-ferromagnetization property is found at a low temperature about ～5 K.