Titan themis 200

Surface topography of printed films was measured via ac-mode atomic force microscopy (AFM, Cipher ES, Oxford Instruments) and surface profilometer (P-7, KLA-Tencor). AFM samples for height profile were prepared by photolithography and wet etching with diluted hydrochloric acid (1:10 in water, v:v). The chemical structure of the ITO was examined by X-ray photoelectron spectroscopy (XPS, ESCALAB XI⁺, Thermo Fisher Scientific) using a monochromatic Al K_α X-ray source. XPS peaks were calibrated by taking C 1s reference at 284.6 eV. XPS depth profile analysis was performed by mild, destructive in-situ sputter etching using a 2000 eV defocused Ar⁺ beam, and monatomic mode to achieve the required depth resolution. Transmission electron microscopy (TEM, Titan Themis 200, FEI) equipped with an energy dispersive X-ray spectrometer (EDS, super-X, Bruker,) was used to obtain the structure and chemical information on the printed oxide TFT. The crystallization and structural information of the films were obtained using X-ray diffraction (XRD, D8 Advance, Bruker) with Cu K_α radiation. The optical transmittance of the printed TFTs were determined with a UV–Vis spectrophotometer (UV-3600Plus, Shimadzu) with spectrum ranging from 300 to 1200 nm.

The microstructure of the wafers was studied with the help of a Titan Themis 200 image corrected transmission electron microscope (FEI, Hillsboro, OR, USA), equipped with a high-brightness field emission gun (X-FEG) electron source and a Super-X detector for energy dispersive spectroscopy (EDS). The heterostructures were investigated at 200 kV by HR-TEM, coupled with selected area electron diffraction (SAED) and scanning transmission electron microscopy (STEM) for elemental line profiling. Prior to analysis, the wafers were mechanically polished and then ion beam milled at a voltage of 3 kV and current of 5 mA until perforation. Ion-beam milling was continued with decrements of voltage and current, in order to remove debris produced by the high voltage ion beam thinning.
For processing the elemental line profiles from EDS data, ImageJ software was used [17 (link)]. The visualization and analysis of crystal structures were made with SingleCrystal^® (Oxford, England), and images of simulated crystals were generated using CrystalMaker^®, a software by CrystalMaker Software Ltd., Oxford, England [18 ].