Epitaxial Growth of CaMnO 3– y Films on LaAlO 3 ( 11 2 ¯ 0 ) by Pulsed Direct Current Reactive Magnetron Sputtering

CaMnO 3 is a perovskite with attractive magnetic and thermoelectric properties. CaMnO 3 films are usually grown by pulsed laser deposition or radio frequency magnetron sputtering from ceramic targets. Herein, epitaxial growth of CaMnO 3– y (002) films on a ( 11 2 ¯ 0 ) ‐oriented LaAlO 3 substrate using pulsed direct current reactive magnetron sputtering is demonstrated, which is more suitable for industrial scale depositions. The CaMnO 3– y shows growth with a small in‐plane tilt of <≈0.2° toward the (200) plane of CaMnO 3– y and the ( 1 ¯ 104 ) with respect to the LaAlO 3( 11 2 ¯ 0 ) substrate. X‐ray photoelectron spectroscopy of the electronic core levels shows an oxygen deficiency described by CaMnO 2.58 that yields a lower Seebeck coefficient and a higher electrical resistivity when compared to stoichiometric CaMnO 3 . The LaAlO 3( 11 2 ¯ 0 ) substrate promotes tensile‐strained growth of single crystals. Scanning transmission electron microscopy and electron energy loss spectroscopy reveal antiphase boundaries composed of Ca on Mn sites along <101> and <002>, forming stacking faults.