Micro-spacing In-air Sublimation Growth of Organic Crystals

Xin Ye, Yang Liu*, Quanxiang Han, Chao Ge, Shuangyue Cui, Leilei Zhang, Xiaoxin Zheng, Guangfeng Liu, Jie Liu, Duo Liu and Xutang Tao*

Chem. Mater. 2018, 30, 2, 412-420

Abstract

Organic single crystals manifest the intrinsic physical properties of materials. However, traditional growth of organic single crystals is limited by low solubility from solutions, or complexity from physical vapor deposition. Here we report a new method to grow organic single crystals by micro-spacing in-air sublimation, which avoids costly vacuum system and time consuming procedures, and is practicable for a wide range of organic crystals. In situ crystal growth observation revealed an unprecedented vapor-to-melt-to-crystal mechanism, being resulted from the micron scale spacing distance between the source and growth position. FET devices based on the rubrene crystals directly grown on Si/SiO₂ substrate exhibited higher mobility than the best record using SiO₂ as the gate dielectric. This effective organic crystal growth technique can be affordable and handled for almost every lab, which may be beneficial for future research and application of organic crystals.