title: A high-vacuum deposition system for in situ and real-time electrical characterization of organic thin-film transistors.
abstract: We present a home-built high-vacuum system for performing organic semiconductor thin-film growth and its electrical characterization during deposition (real-time) or after deposition (in situ). Since the environment conditions remain unchanged during the deposition and electrical characterization process, a direct correlation between growth mode and electrical properties of thin film can be obtained. Deposition rate and substrate temperature can be systematically set in the range 0.1-10 ML∕min and RT-150 °C, respectively. The sample-holder configuration allows the simultaneous electrical monitoring of up to five organic thin-film transistors (OTFTs). The OTFTs parameters such as charge carrier mobility μ, threshold voltage V(TH), and the on-off ratio I(on)∕I(off) are studied as a function of the semiconductor thickness, with a submonolayer accuracy. Design, operation, and performance of the setup are detailed. As an example, the in situ and real-time electrical characterization of pentacene TFTs is reported.
authors.affiliation: Consiglio Nazionale delle Ricerche, Istituto per lo Studio dei Materiali Nanostrutturati, Bologna, Italy.
authors.forename: Santiago David
authors.initials: SD
authors.lastname: Quiroga
authors.forename: Arian
authors.initials: A
authors.lastname: Shehu
authors.forename: Cristiano
authors.initials: C
authors.lastname: Albonetti
authors.forename: Mauro
authors.initials: M
authors.lastname: Murgia
authors.forename: Pablo
authors.initials: P
authors.lastname: Stoliar
authors.forename: Francesco
authors.initials: F
authors.lastname: Borgatti
authors.forename: Fabio
authors.initials: F
authors.lastname: Biscarini