Ultrathin silica film derived with ultraviolet irradiation of perhydropolysilazane for high performance and low voltage organic transistor and inverter

In recent years, organic electronic devices have become more and more popular, such as organic solar cell （OSC） [1-4], organic light emitting diode （OLED） [5-7] and organic thin film transistor （OTFT） [8-11] by virtue of their light weight, easy-processing and flexibility.

Fabrication of flexible thin organic transistors by trace water assisted transfer method

The development of fabrication method for flexible thin organic electronic device is highly important for the flexible and wearable products. Herein, we develop a facile peel-off method to transfer organic thin film to various substrates. In this strategy, polyacrylonitrile （PAN） film can be easily peeled offwith trace water and further transferred to various substrates. Using PAN as supporting and dielectric layers, high performance flexible organic transistors are fabricated. Remarkably, the method uses only micro volume water as an assist to peel off PAN film, which reduces the risk of contamination by solvent and greatly contributes to the performance maintenance.

Eggshell-inspired membrane—shell strategy for simultaneously improving the sensitivity and detection range of strain sensors

The tradeoff between sensitivity and detection range(maximum and minimum stretchability)is a key limitation in strain sensors;to resolve this,we develop an efficient and novel strategy herein to fabricate a highly sensitive and stretchable strain sensor inspired by the membrane-shell structure of poultry eggs.The developed sensor comprises a soft and stretchable surface-grafting polypyrrole(s-PPy)film(acting as the membrane)and a brittle Au film(acting as the shell),wherein both films complement each other at the electrical and mechanical levels.Au forms cracks under strain contributing to its high sensitivity and low detection limit,and s-PPy can bridge Au cracks and increase stretchability which has not been used in strain sensors before.The surface-grafting strategy not only enhances interface adhesion but also tunes the brittle property of native PPy to render it stretchable.Utilizing the synergetic effect of the membrane-shell complementary structure,the strain sensors achieve ultrahigh sensitivity(>10^(7)),large stretchability(100%),and an ultralow detection limit(0.1%),demonstrating significant progress in the field of strain sensors.The membrane-shell(Au/s-PPy)-structured strain sensor can successfully detect finger motion,wrist rotation,airflow fluctuation,and voice vibration;these movements produce strain in the range of subtle to marked deformations.Results evidence the ultrahigh performance and bright application prospects of the developed strain sensors.

Solution-processable precursor route for fabricating ultrathin silica film for high performance and low voltage organic transistors

Silica is one of the most commonly used materials for dielectric layer in organic thin-film transistors due to its excellent stability, excellent electrical properties, mature preparation process, and good compatibility with organic semiconductors. However, most of conventional preparation methods for silica film are generally performed at high temperature and/or high vacuum. In this paper, we introduce a simple solution spin-coating method to fabricate silica thin film from precursor route, which possesses a low leakage current, high capacitance, and low surface roughness. The silica thin film can be produced in the condition of low temperature and atmospheric environment. To meet various demands, the thickness of film can be adjusted by means of preparation conditions such as the speed of spin-coating and the concentration of solution. The p-type and n-type organic field effect transistors fabricated by using this film as gate electrodes exhibit excellent electrical performance including low voltage and high performance. This method shows great potential for industrialization owing to its characteristic of low consumption and energy saving, time-saving and easy to operate.

Tuning the aggregation structure and electrical property of 2.6-diphenyl-anthracene by the density of octadecyltrichlorosilane

The physical and chemical properties of organic semiconductors are closely related to their aggregation structure. Tuning of aggregation structure and electrical property is important for the application in organic electronics. In this study, a facile way to tune the aggregation structure and electrical property of 2.6-diphenyl-anthracene(DPA) is realized by using the octadecyltrichlorosilane(OTS) modification layer with different density which is fabricated by controlling reaction temperature and time.Compared with low density OTS, DPA forms larger grain size, less grain boundaries, and better molecular ordering on high density OTS surface. As a result, the charge transporting mobility of DPA film on high density OTS surface is about two orders of magnitude higher than that on low density OTS surface. The tunable aggregation structure and electrical property of DPA demonstrated here would be meaningful for the application of DPA in organic electronics.