Yang Hoichang, Shin Tae Joo, Ling Mang-Mang, Cho Kilwon, Ryu Chang Y, Bao Zhenan
Rensselaer Nanotechnology Center, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
J Am Chem Soc. 2005 Aug 24;127(33):11542-3. doi: 10.1021/ja052478e.
Among all organic semiconductors, pentacene has been shown to have the highest thin film mobility reported to date. The crystalline structure of the first few pentacene layers deposited on a dielectric substrate is strongly dependent on the dielectric surface properties, directly affecting the charge mobility of pentacene thin film OTFTs. Herein, we report that there is a direct correlation between the crystalline structure of the initial submonolayer of a pentacene film and the mobility of the corresponding 60-nm-thick films showing terrace-like structure, as confirmed by 2D grazing-incidence X-ray diffraction and atomic force microscopy. Specifically, multilayered pentacene films, grown from single crystal-like faceted islands on HMDS-treated surface, have shown much higher charge mobility (mu = 3.4 +/- 0.5 cm2/Vs) than those with polycrystalline dendritic islands (mu = 0.5 +/- 0.15 cm2/Vs) on OTS-treated ones.
在所有有机半导体中，苝已被证明具有迄今为止报道的最高薄膜迁移率。沉积在介电基板上的最初几层苝的晶体结构强烈依赖于介电表面性质，直接影响苝薄膜有机晶体管的电荷迁移率。在此，我们报告，通过二维掠入射X射线衍射和原子力显微镜证实，苝薄膜初始亚单层的晶体结构与相应的60纳米厚的呈梯田状结构的薄膜的迁移率之间存在直接关联。具体而言，在经六甲基二硅氮烷处理的表面上由单晶状刻面岛生长而成的多层苝薄膜，其电荷迁移率（μ = 3.4 ± 0.5 cm²/Vs）比在经十八烷基三氯硅烷处理的表面上具有多晶树枝状岛的薄膜（μ = 0.5 ± 0.15 cm²/Vs）高得多。
