One important technical hurdle that has to be overcome for using organic transistors in radio-frequency identification tags is for these devices to operate at rf frequencies (typically 13.56MHz) in the front end. It was long thought that organic transistors are too slow for this. In this letter we show that organic transistor based full-wave rectifier circuits utilizing pentacene, a p-channel organic semiconductor, can operate at this frequency with a useful efficiency. In order to achieve such high-frequency operation, we make use of the nonquasistatic state of the transistors.

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Printed electronic circuits have been explored for low-cost, large-area applications, such as displays and radio frequency identification tags, where the promise of inexpensive solutionbased fabrication techniques is more crucial than the fast circuit speeds associated with conventional inorganic semiconductors. [1][2][3][4][5][6][7][8] In order for such low-cost, portable devices to become a reality, high-mobility, air-stable, n-channel organic field-effect transistors (OFETs) are required to enable the fabrication of organic complementary metal oxide semiconductor (CMOS) circuits that would operate at sufficient speeds and with low power dissipation. Additionally, the semiconductors must be solution processable to be compatible with the inexpensive fabrication techniques envisioned for printed electronics. Whereas most examples of printed organic semiconductors are conjugated p-type polymers, solution-processed OFETs with small molecules are far less common. [9,10] Previously, the small molecule semiconductor N,N′-bis(n-octyl)-(1,7&1,6)-dicyanoperylene-3,4:9,10-bis(dicar-boximide) (PDI-8CN 2 ) was used to fabricate promising vapordeposited n-channel OFETs with excellent electrical performance and remarkable environmental stability. [11,12] Because PDI-8CN 2 is soluble in common solvents such as chloroform, toluene, and dichlorobenzene, an intriguing question of whether it could be used for fabricating complex complementary organic circuits using solution-based processing techniques is raised. We report here the first fabrication of highperformance n-channel organic transistors and their complementary circuits from a PDI-8CN 2 solution with a micro-injector patterning technique. This work advances the pioneering results of Katz et al., [13] who fabricated a simple organic complementary inverter with a shadow-masked top-contact geometry. Unfortunately, such simple fabrication methods are not scalable for shrinking channel lengths to technologically useful sizes or for increasing the circuit complexity beyond inverter structures. These last two points represent the crossing of major technical hurdles in the development of organic complementary circuit technology. For the present OFET device fabrication, the organic semiconductor solutions were patterned in a nitrogen atmosphere using an Intracel Picospritzer, a pneumatically actuated micro-injector where droplet size is controlled by gas pressure and jetting time. The OFET gate dielectric and gold source/ drain electrode surfaces were treated with self-assembled monolayers (SAMs) to improve the surface energy match with the organic semiconductors and to produce approximately hemispherical solution droplets. Solvent selection proved crucial to the formation of uniform semiconductor films-for example, low-boiling solvents, such as chloroform, leave residue on the micropipette tip, adversely affecting the deposition process and the resultant film morphology. However, high-boiling solvents, such as 1,2-dichlorobenzene (bp 174°C) do not adversely affect the solution de...

The time dependence of the current transient i(t) produced by the reversal of domains in ferroelectric potassium nitrate thin-film memories of 75–300 nm is analyzed as a function of temperature and of thickness using the Avrami theory. For all the films the kinetics confirm the low-dimensional nature of the system

The development of organic complementary circuits has been largely limited by the development of suitable organic n-channel transistors. However, recent advances have led to materials such as the high-mobility air-stable n-channel organic semiconductor, N, N -bis(n-octyl)-dicyanoperylene-3, 4 : 9, 10-bis (dicarboximide), PDI-8CN 2 . Here, the fabrication of an organic complementary D flip-flop using PDI-8CN 2 n-channel transistors and pentacene p-channel transistors is described. The measured clock-to-output delay is 25 µs for 1 kHz, and 14 µs at the clock frequency of 5 kHz. This is the fastest clock speed for an organic complementary circuit yet achieved.