Micrometer- and Nanometer-Sized Organic Single Crystalline Transistors

Single crystal devices of organic semiconductors have attracted worldwide attention due to (i) the high performance of organic single crystalline devices and (ii) the possibility of single crystals to reveal the intrinsic chargetransport properties of organic semiconductors. Normally, organic crystals exist as nanometeror micrometer-sized ‘‘small’’ crystals because of the weak interaction between the molecules of organic semiconductors, and it is challenging to grow large size organic single crystals for devices, even the crystals at millimeter size. Hence, if devices could be fabricated by using the ‘‘small’’ organic crystals directly, it will be beneficial to not only keep all the advantages of organic single crystals and avoid the challenge for the growth of large-sized crystals, but also provide a way to characterize organic semiconductors more efficiently. Furthermore, the effective using of the ‘‘small’’ crystals will be meaningful for the integration of organic single crystals to microand nanoelectronic devices. Unfortunately, traditional inorganic microfabrication techniques such as electro-beam/focused ion beam depositions will damage or pollute organic crystals, which limit the application of the inorganic microfabrication techniques for organic single crystalline devices. So, new technologies to fabricate devices with ‘‘small’’ organic crystals must be developed. Recently, the researchers in Institute of Chemistry, Chinese Academy of Science, explored several