Due to high hole mobility, pentacene and its derivatives have been the representative organic semiconductor and have been the subject of much research, both basic and applied. In particular, they are expected to be applied to semiconductor devices, such as field-effect transistors. In addition, organic semiconductors have the advantage of being inexpensive to produce through inkjet printing, and they have low environmental impacts because they do not use metals. However, the backbone of organic semiconductors, such as pentacene, easily reacts with oxygen molecules under visible light, resulting in the loss of useful properties.