Magnetron sputtering generally increases the temperature of the substrate placed to face the sputtering target above 40 °C because the plasmas are transported through unbalanced magnetic field lines from the sputtering target to the substrate surface. However, by using a magnetic mirror-type magnetron cathode, we were able to suppress the temperature of the substrate temperature to the environmental temperature of less than 40 °C at a target–substrate distance of ≥50 mm with a DC input power of ≤30 W and an Ar gas pressure of ≤0.15 Pa. This was possible because the balanced magnetic field lines confined the plasmas near the sputtering target. By enabling film deposition on low heat-resistant substrates, this deposition technique for suppressing the substrate temperature may have uses in various application fields.
