MgB2 thin films and Josephson devices

Since the recent discovery of superconductivity in MgB₂, various groups worldwide have been actively studying the growth of thin films based on this material. Impressive progress has been made, but various materials science challenges are still left to be solved. Guided by our own activities in this field, and reports presented in the literature, we reflect here on those challenges and possible ways for further improvement. Being important ingredients for many electronic applications, fabrication of Josephson devices and nano-structures in MgB₂ thin films will furthermore be described.