In this study, we focused our interests on the write-once storage media. We choose two kinds of recording materials. One is phase change material which is Ge-Sb-Te, and the other we adopted CrOx. . For CrOx thin film, according to information we found that the gas could be released from the layer as the heating temperature over 400 ℃. When signal was be written, the phase change material would convert crystal into amorphous. Then , we could use erasing power to clean original signal, and this action can make amorphous return to crystal. This situation would be convert again and again. Therefore, we use the released gas to break the phase change layer. After the signal was be written, the disc cannot return to crystal from amorphous. Finally, we got write-once storage media through a series design optimization of layer structure.