With the development of novel device applications, e.g. in the field of robust and recyclable paper electronics, came an increased demand for the understanding and control of IGZO Schottky contact properties. In this work, a fabrication and characterization of flexible Ru-Si-O/ IGZO Schottky barriers on paper is presented. It is found that an oxygen-rich atomic composition and microstructure of Ru-Si-O containing randomly oriented Ru inclusions with diameter of 3-5 nm embedded in an amorphous SiO 2 matrix are effective in preventing interfacial reactions in the contact region, allowing to avoid pre-treatment of the semiconductor surface and fabricate reliable diodes at room temperature characterized by Schottky barrier height and ideality factor equal 0.79 eV and 2.13, respectively.

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In a recently published paper, suggestions have been contained concerning close relations existing between the position of the inflection point on the capacitance-voltage, C(VG), characteristic of the metal-oxide-semiconductor (MOS) structure and the position of the flat-band voltage of this structure. In this article, a systematic, quantitative analysis of this problem is presented. The analysis of the relations existing between the voltage of the inflection point VINFL on the capacitance-voltage, C(VG), characteristic and the flat-band voltage, VFB, of a MOS structure is conducted for ideal and non-ideal (but with negligible density of interface states, Dit) MOS structures on silicon and silicon carbide substrates. It is found that, in general, there is a significant difference between the VINFL and the VFB values. The VINFL − VFB difference is found to depend primarily on the substrate doping density ND and on the dielectric layer thickness tOX. This difference is calculated for a range of ND and tOX values for structures with negligible Dit values on silicon and silicon carbide substrates. Experiments are described which were conducted to allow comparison of calculated and experimentally obtained VINFL values of different MOS structures on Si and SiC substrates. Results of these experiments support the quantitative results of our analysis for structures with negligible densities of interface states. As expected, for structures with higher Dit values, significant differences are found between calculated and experimentally obtained VINFL values.

MOS capacitors were fabricated on 3C-SiC n-type substrate (001) with a 10-μm N-type epitaxial layer. An SiO2 layer of the thickness tOX ≈55 nm was deposited by PECVD. Circular Al, Ni, and Au gate contacts 0.7 mm in diameter were formed by ion beam sputtering and lift-off. Energy band diagrams of the MOS capacitors were determined using the photoelectric, electric, and optical measurement methods. Optical method (ellipsometry) was used to determine the gate and dielectric layer thicknesses and their optical indices: the refraction n and the extinction k coefficients. Electrical method of C = f(VG) characteristic measurements allowed to determine the doping density ND and the flat band voltage VFB in the semiconductor. Most of the parameters which were necessary for the construction of the band diagrams and for determination of the basic physical properties of the structures (e.g. the effective contact potential difference ϕMS) were measured by several photoelectric methods and calculated using the measurement data. As a result, complete energy band diagrams have been determined for MOS capacitors with three different gate materials and they are demonstrated for two different gate voltages VG: for the flat-band in the semiconductor (VG = VFB) and for the flat-band in the dielectric (VG = VG0).