TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Disclosed): An amino group-containing compound of formula (1c) and halogen compound of formula: R1-X are reacted in the presence of a base e.g. sodium hydride and n-butyllithium, and a solvent e.g. N,N-dimethylformamide, and an aliphatic hydrocarbon group is introduced into nitrogen atom of compound (1c) to obtain dibenzo phenoxazine compound (I).X=chloro or bromo.Preferred Layer: The organic-semiconductor layer is provided on a hydrophilic film. The field effect transistor further has a gate electrode (12), a gate insulating film, a source electrode (14), and a drain electrode (15). The organic-semiconductor layer is provided such that it opposes with the gate electrode through the gate insulating film, and the source electrode and a drain electrode are contacted on the organic-semiconductor layer. The compound (I) is coated and the organic-semiconductor layer is formed. The compound (I) is vapor-deposited and organic-semiconductor layer is formed. The solar cell has organic-semiconductor layer containing p-type-semiconductor material and n-type-semiconductor material, in which at least one contains the compound (I). The organic light emitting element is provided with a carrier transport layer containing the compound (I). SPECIFIC COMPOUNDS - 50 Dibenzo phenoxazine compounds e.g. 13-hexyl-13H-6-oxa-13-azapentacene of formula (Ia), 13-octyl-13H-6-oxa-13-azapentacene, 13-dodecyl-13H-6-oxa-13-azapentacene, 13-octadecyl-13H-6-oxa-13-azapentacene, and 13-hexyl-2,10-diphenyl-13H-6-oxa-13-azapentacene are specifically disclosed.    EXAMPLE - After adding sodium hydride (60 mg) to anhydrous-dimethyl formamide solution (10 mL) of 13H-6-oxa-13-azapentacene (257 mg) and setting at room temperature for 2 hours, 1-bromo-hexane (0.25 g) was added and stirred for 2 hours. The solvent was distilled off under reduced pressure, extracted with methylene chloride, and 13-hexyl-13H-6-oxa-13-azapentacene (0.28 g) was obtained at yield of 45% from the residue after solvent distillation with silica gel column chromatography.