[en] The Fast Ignition Realization EXperiment (FIREX) project was launched at the Institute of Laser Engineering (ILE), Osaka University. Key technologies are developments of high-energy lasers and solid fuel targets, also called a cryogenic target. ILE and the National Institute for Fusion Science (NIFS) started a cooperative study on the target in 2003. It has a unique appearance designed for the project. To realize its specifications, a foam shell method is applied as a fuel layering technique. Subjects of the target development are fabrication of a foam shell, assembling the foam shell and other parts to form the target, and fuel layering. In this paper, accomplishments and some remaining issues of the target development are described. (author)