Various Detrapping Processes in Anthraquinone-Doped Anthracene Crystal
The photo-carrier generation process by optical detrapping effects has been observed in anthracene crystals provided with hole and electron injecting contacts. It has been reported that there were the direct release of trapped carriers from traps about 1 eV to conduction state and the indirect release due to the interaction of the trapped carriers and two types of excitons, that is, triplet and singlet excitons. On the other hand, it is expected that there are deeper traps than 1 eV in impurity-doped anthracene crystals. In fact, it was found that free carriers in electrical conduction were generated thermally from such deep traps in doped anthracene crystals. In this note, various detrapping processes which include the direct release from the deeper traps than 1 eV are investigated in anthraquinone-doped anthracene crystal. Further, it is reported that the enhancement of the photocurrent by the optical detrapping effects is observed in the crystal provided with non-injecting contacts, when the traps have been charged with carriers before measurements.[4, 5]
KeywordsTrap Electron Deep Trap Trap Hole Photo Current Dark Conduction
Unable to display preview. Download preview PDF.
- U. Itoh and H. Anzai; submitted to J.Phys.Soc.Japan.Google Scholar