The long-term target of producing all-organic devices requires custom-designed dielectric materials able to be applied and patterned with a wide range of new and fast deposition and patterning methods. Inorganic-organic hybrid polymers such as organic modified ceramics (ORMOCERs) have recently gained considerable attention in polymer electronics. Consisting of organically functionalized inorganic-oxidic units, their material properties can be tuned over a wide range and, in addition, their processing is very flexible providing good compatibility to many materials and substrates and allowing for direct patterning. A study on the application of different ORMOCER systems as gate dielectric layers in organic thin-film transistors (OTFTs) with pentacene as the organic semiconductor and directly structured contact holes is presented. Depending on the chemistry of the underlying ORMOCER system, different morphologies of the thermally evaporated pentacene were observed and correlated to the electrical characteristics of the transistor devices. In some cases, OTFTs with excellent electrical performance were achieved, showing intrinsic field-effect mobility values up to 1 cm(2)/V s. Based on the high charge-carrier mobility of the pentacene-ORMOCER interface and the good dielectric, passivating, and patterning properties of the ORMOCER materials, these devices lay the foundation for a new generation of high-quality, fast, processable low-cost organic electronics
This study demonstrates the use of optical coherence tomography (OCT) to simultaneously characterize the roughness of the tablet core and coating of pharmaceutical tablets. OCT is a high resolution non-destructive and contactless imaging methodology to characterize structural properties of solid dosage forms. Besides measuring the coating thickness, it also facilitates the analysis of the tablet core and coating roughness. An automated data evaluation algorithm extracts information about coating thickness, as well as tablet core and coating roughness. Samples removed periodically from a pan coating process were investigated, on the basis of thickness and profile maps of the tablet core and coating computed from about 480,000 depth measurements (i.e., 3D data) per sample. This data enables the calculation of the root mean square deviation, the skewness and the kurtosis of the assessed profiles. Analyzing these roughness parameters revealed that, for the given coating formulation, small valleys in the tablet core are filled with coating, whereas coarse features of the tablet core are still visible on the final film-coated tablet. Moreover, the impact of the tablet core roughness on the coating thickness is analyzed by correlating the tablet core profile and the coating thickness map. The presented measurement method and processing could be in the future transferred to in-line OCT measurements, to investigate core and coating roughness during the production of film-coated tablets.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.