Highly precise multi-cathode pulsed-DC sputtering employing digital processing–application to layer–by–layer synthesis of cubic (Er0.1Y0.9)2Zr2O7 thin film

Abstract A digitally processed DC reactive sputtering (DPDRS) system employing field-programmable gate-array has been developed. In this report, atomically precise pulsed-DC sputtering of a metal oxide compound, cubic (Er 0.1 Y 0.9 ) 2 Zr 2 O 7 (c-EYZO), is demonstrated by using DPDRS. An alternating process of pulsed metal sputtering and reactive gas pulsing was applied in order to realize layer-by-layer reactive sputtering. The pulsed metal sputtering separated from the oxidation process results in a stable and high deposition rate of c-EYZO at 1.9 μ m h −1 , which corresponds to 1.56 nm/cycle. By adjusting the deposition rate to the d-spacing of 0.26 nm corresponding to the (200) diffraction, layer-by-layer synthesis of a highly oriented c-EYZO thin film showing the d-spacing was achieved. X-ray diffraction and photoluminescence measurements indicate drastic improvement of the crystalline properties and the emission properties due to the layer-by-layer synthesis. It is expected that DPDRS enables arbitrarily designed atomically precise deposition of the metal oxide compound synthesis.