[23a-E206-1~10] 12.4 Organic light-emitting devices and organic transistors

▼ [23a-E206-2] Temperature-dependent FET properties and charge transport capabilities of dibenzo[n]phenacenes (n = 5 -7)

〇(D)Yanting Zhang¹, Shino Hamao¹, Hidenori Goto¹, Kunihisa Sugimoto², Nobuhiro Yasuda⁴, Akihiko Fujiwara³, Yoshihiro Kubozono¹, Hideki Okamoto⁴, Ritsuko Eguchi¹ (1.RIIS, Okayama Univ., 2.JASRI/SPring-8, 3.Kwansei Gakuin Univ., 4.Chem. Okayama Univ.)

Keywords:temperature-dependent FET properties, charge transport capabilities

In this work, the trap states generated at the interface between gate dielectrics and single crystal of DBnPs were quantitatively estimated from the temperature-dependent FET properties based on the multiple trap and release (MTR) model. Figure 1(a) shows the temperature-dependent m values for DBnP single-crystal FETs. The intrinsic mobility m₀ which refers to the m value without any trap states was the highest for DB6P, and the ratio of the number of total trap states, N_t, with respect to that of valence states, N_v, was the smallest for DB6P. These results predict the highest FET performance for DB6P FET. The transfer integrals between adjacent molecules were calculated based on the molecular coordinates obtained by the single crystal X-ray diffraction of DBnPs, indicating that the transfer integrals were the largest for DB6P (Figure 1(b)), which also explains reasonably the excellent FET performance in the DB6P single-crystal FET. Thus, it has been found that the most significant factors dominating the transport characteristics in DBnP single-crystal FETs may be the closed molecular packing (or high transfer integrals) in the crystal lattice, in addition to the small trap density in DB6P.