Single layer graphene has attracted intense research interest since its discovery in 2003. However, difficulties in producing single layer specimens have encouraged the development of chemical routes. One such method is the oxidation, exfoliation, and subsequent reduction of graphite oxide through solution processing. Although graphite oxide produced specimens have been used to fabricate electrical devices, wafer scale processing has not yet been achieved due to the inability of registration in well-defined locations. Here we report a transfer printing process that allows for precise patterning of chemically derived graphene. Utilizing a polydimethylsiloxane (PDMS) stamp and the manipulation of surface energies, we successfully transfer spin-coated materials from one substrate to another. The method is capable of transferring sharp features to precise locations as confirmed by Raman mapping. This represents the first large scale, high throughput transfer printing of graphene and paves the way for future complementary circuit design.

Organic materials are becoming of great appeal also in the field of e-textiles, as they show an interesting combination of electronic and mechanical properties that can be favourably exploited in smart textiles.We present an example of organic field effect transistor (OFET) characterized by textile process fully compatible size and geometry. The devices have been obtained starting from a cylindrical metal fibre with typical diameters ranging around 45-60 µm, acting as the gate electrode, covered by a uniform insulating layers (polymide, and polypyrrole in the undoped state), which acts as the gate dielectric for the final device. As a result, this yarn is very flexible and can be employed, alone or twisted to another fibre, in textile processes.Different organic semiconductors were tested as the active layer forming the channel of the final device, and were deposited directly on the bare insulating yarn surface, while source and drain electrodes were realized afterwards in order to obtain a top contact configuration. AFM and SEM measurements demonstrated that both the dielectric and the organic semiconductor layers were uniformly deposited on the structure allowing to obtain well performing devices.When pentacene was used as organic semiconductor we obtained high performances unipolar p-type OFETs with an average hole mobility very close to 0.1 cm^2/Vs, and Ion/Ioff up to 10^4. In this paper we will show also how, thanks to the flexibility of the final structure, these devices can be employed as deformation sensors, as the output current varies reproducibly by applying a mechanical stimulus to the whole structure.Moreover, we will show how, using a double layer structure as active layer, employing pentacene/C60 heterojunction, it was possible to obtain ambipolar OFETs devices with very good mobility, up to 3x10^-2cm^2/Vs and 1.5x10^-2cm^2/Vs for the p- and n-type regime respectively. This was possible thanks to the improvements of the C60 layer structural and morphological characteristics, as supported by AFM and XRD characterization, which allowed, even by using high work function metals (Cu, Au and PEDOT:PSS) for the realization of the source and drain electrodes, to obtain a very efficient electron injection into the channel. These findings are very important because demonstrate the possibility of realizing organic complementary circuits by using very thin yarns suitable to be employed into a textile process. We will show our first preliminary attempts on the realization of complementary inverters by using the reported technology, which paves the way for the easy realization of smart wearable electronics.