Nanograting layers of Si

Abstract

The paper presents research regarding the complex behavior of materials based on Si and SiO2, geometrically processed at nano-scale. The geometry, which induces the doping effect (G-doping), occurred when it was possible to fabricate nanograting structures. Studies on the influence of nanograting structures on the properties of materials have shown that this process may lead to effects similar to those created by doping with donors. The resistivity values measured in Si-based nanograting layers, for example, were approximately 10−2 Ω cm, similar to those of Si semiconductors doped with phosphorus ‘impurities’ having a volume concentration of 1018 cm−3. This increase in electronic properties, as a result of the nanograting structure, seems to appear due to the fact that the electrons rejected in the process are placed in the structure vacancies. It has been experimentally proven that, in the case of semiconductors, the nanograting structuring makes the rejected electrons from the valence band to be placed in the conduction band. In the paper, after samples fabrication with nanograting structures on Si films placed on SiO2 support, the I–V curves of the obtained layers were drawn, both by measuring in four points and also in two points. The resistivity measurements were made in two directions: along and perpendicular to the strips of the structure and showed the existence of an anisotropy.

Wettability and Surface Roughness Analysis of Laser Surface Texturing of AISI 430 Stainless Steel

“…Enhancing fundamental characters, such as sustainability, tribological and biocompatibility, LST offers precise control regarding the main parameters of the characterization of microstructures (shape, roughness, width, depth, size, recast material, etc.). For modifying the surface of materials to obtain microstructures, in previous literature different approaches such as plasma treatment [1], electrochemical procedures [2], and micro-processes such as grinding [3,4], cutting [5], machining by ultrasonic or laser [6][7][8][9][10][11][12][13] and laser chemical processing (combination of chemical cleaning and laser interference lithography) [14] were used. For this research, the LST is preferred since offers a high-quality precision, a way to be automatized, and because nearly any type of material can be used, and with a low cost.…”

Morphological Analysis of Laser Surface Texturing Effect on AISI 430 Stainless Steel

“…Laser surface texturing (LST) is a widely used method worldwide for surface functionalization [1][2][3][4], being used in various fields: medical implants [5][6][7][8][9][10][11], wettability tuning [12], optical properties [13,14], hybrid joining [15][16][17], increasing adhesion [18], or cutting tools [19][20][21][22]. The materials that are the object of microtexturing are varied, from dentin and enamel materials, to polymers, ceramics, ferrous and non-ferrous metallic materials, and finally composite materials, in various domains such as engineering, medicine, bioengineering, etc.…”

G-Doping-Based Metal-Semiconductor Junction

“…Current developments in nanotechnology have enabled patterning the surface of semiconductor layers by nanoscale gratings with periodical arrays of width smaller than 1 µm [1][2][3][4]. Nanograting (NG) patterns have been shown to dramatically change the electronic [5][6][7], magnetic [8,9], optical [10][11][12][13][14], and electron emission [15,16] properties of the semiconductor substrate when the grating depth becomes comparable with de Broglie wavelength of electrons. This can be attributed to the special boundary conditions enforced by the NG on the wave function.…”