PTCDI-C8 due to its relatively high photosensitivity and high electron mobility has attracted much attention in organic semiconductor devices. In this work, thin films of PTCDI-C8 with different thicknesses were deposited on silicon substrates with native silicon dioxide using a vacuum thermal evaporator. Several material characterization techniques have been utilized to evaluate the structure, morphology, and optical properties of these films. Their optical constants (refractive index and extinction coefficient) have been extracted from the spectroscopic ellipsometry (SE). X-ray reflectivity (XRR) and atomic force microscopy (AFM) were employed to determine the morphology and structure as well as the thickness and roughness of the PTCDI-C8 thin films. These films revealed a high degree of structural ordering within the layers. All the experimental measurements were performed under ambient conditions. PTCDI-C8 films have shown to endure ambient condition which allows pots-deposition characterization.

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The effects of strain on the conduction mechanism in heterostructures consisting of strained nano-thin 3C–SiC films on Si are reported. These films exhibit significantly different electrical behaviours than the bulk material. Strained nano-thin 3C–SiC films were grown on n-type Si substrates by gas source molecular beam epitaxy. Reflection high-energy electron diffraction patterns show that these films are about 3% strained relative to the SiC lattice constant. In order to investigate the electrical properties of thin film structures, Al, Cr and Pt contacts to a nano-thin film 3C–SiC were deposited and characterized. The I–V measurements of the strained nano-thin films demonstrate back-to-back Schottky diode characteristics and the band offsets due to the biaxial tensile strain introduced within the 3C–SiC films were calculated and simulated. Based on the experimental and simulation results, an empirical model for the current transport in the heterostructures based on strained nano-thin films has been proposed. It was found that due to the band alignment of this structure, current is constrained at the surface which allows use of nano-thin films as surface sensors.

Several CuPc/PTCDI-C8 films with different structures (co-deposited, layered, and bilayer) were prepared and their structural properties were studied using X-ray diffraction. In order to study the effects of the active layers' structures on the performance of the device, organic solar cells based on these films were fabricated and their electrical characteristics have been explored. Absorbed prominent diffraction peaks for CuPc/PTCDI-C8 bilayer films indicate the formation of higher degree of crystallinity for this structure compared to the films with layered or co-deposited structures. This crystallinity results in higher device performance due to reduced recombination losses and microscopic shorts within the devices.

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