有机半导体材料蒽薄膜的生长

Thin Film Growth of Organic Semiconductor Anthracen

利用常规的真空蒸发技术,在热氧化硅片的衬底上沉积了蒽薄膜。用扫描电子显微镜(SEM)和原子力显微镜(AFM)对不同沉积时间的蒽薄膜形貌进行了观察,研究了蒸发沉积蒽膜时膜在二氧化硅衬底上的成核和生长模式,并借助X射线衍射仪(XRD)分析了薄膜的结晶状态。结果显示:蒽膜生长时,蒽的临界核以Volmer-Weber模式生长,即蒽首先形成许多三维岛状的晶核,核长大增高为岛,然后在蒽离域大π键的作用下,相邻的两层蒽分子存在一定程度的交叠,岛与岛相互连接构成岛的通道,最后形成均匀致密、具有良好晶体特性的多晶薄膜。

The thin films of organic semiconductor anthracen were fabricated on SiO2 substrate by traditionary vacuum sublimation. The surface morphology, nucleation and growth of anthracen thin film were studied by observing a series of samples grown under different depositing times with SEM and AFM. It indicates that the growth mode of anthracen deposited onto SiO2substrates follows the Volmer-Weber mode, namely, firstly, anthracen molecules form lots of three-dimensional island-like anthracen crystal nuclei, and nuclei grew into islands; then by the action of delocalized big 7v bond, two adjacent layers of anthracen molecules overlap to some extent, and the islands connected to form channels and finally, symmetric and compact films were produced with excellent crystal properties.