Growth of high-quality large-area MgB2thin films by reactive evaporation

We report a new in situ reactive deposition thin film growth technique for the production of MgB 2 thin films which offers several advantages over all existing methods and is the first deposition method to enable the production of high-quality MgB 2 films for real-world applications. We have used this growth method, which incorporates a rotating pocket heater, to deposit MgB 2 films on a variety of substrates, including single-crystalline, polycrystalline, metallic, and semiconductor materials up to 4 inch in diameter. This technique allows growth of double-sided, large-area films in the intermediate temperature range of 400–600 °C. These films are clean, well-connected, and consistently display T c values of 38–39 K with low resistivity and residual resistivity values. They are also robust and uncommonly stable upon exposure to atmosphere and water.