105 results about "Yttrium(III) oxide" patented technology

The application discloses a lithium-free high-heat-resistant ceramic mud and a preparation method thereof, and relates to the technical field of ceramic materials. In the preparation of the lithium-free high-heat-resistant ceramic mud, alumina is reacted with 3-(2,3-epoxypropoxy) propyl trimethoxysilane to obtain pre-modified alumina; the pre-modified alumina is reacted with starch to obtain modified alumina; ethyl acetoacetate, isopropyl alcohol, zirconium oxychloride, aluminum sec-butoxide, polyvinylpyrrolidone and N-N dimethylformamide are mixed to form a spinning solution, the spinning solution is electrospun, and then immersed in yttrium oxide sol to obtain alumina-zirconia-yttria composite fibers; the modified alumina, talc, alumina-zirconia-yttria fibers, hydroxypropyl methyl cellulose, glycerol, oleic acid, polyethylene glycol and water are stirred and mixed, and vacuum pugging is carried out to obtain the lithium-free high-heat-resistant ceramic mud. The lithium-free high-heat-resistant ceramic mud prepared by the application has good thermal shock resistance and bending strength after sintering.

The application relates to the technical field of functional ceramics, and mainly relates to a ceramic material for a ceramic heater and a preparation method thereof. The ceramic material for the ceramic heater comprises the following raw materials: 90-100 parts by weight of alumina; 5-10 parts by weight of modified calcium silicate glass powder; 0.1-1 part by weight of yttrium oxide; 5-15 parts by weight of modified zirconium oxide; 0.1-1 part by weight of silicon dioxide; 0.1-1 part by weight of magnesium oxide; 1-5 parts by weight of a binder; and the preparation raw materials of the modified calcium silicate glass powder comprise quartz sand, limestone and alumina. The ceramic material for the ceramic heater provided by the application is excellent in thermal shock resistance, thermal conductivity, mechanical properties and the like, and can well adapt to the application scene of the ceramic heater.

This invention relates to the field of special ceramics preparation technology, and discloses a process for preparing high thermal conductivity ceramic materials for high-nickel ternary cathode sintering, including: preparing magnesium aluminum spinel green blanks containing magnesium oxide, yttrium oxide and titanium oxide composite additives; performing cyclic variable oxygen pressure sintering at 1420℃ to 1480℃, controlling the furnace atmosphere to periodically switch between the first and second oxygen partial pressure states. This invention utilizes the oxygen potential difference to drive the grain boundary liquid phase to alternate between low viscosity wetting and high viscosity pinning characteristics, eliminating the rheological quiescent zone at the end of sintering, effectively suppressing abnormal grain growth while ensuring high material density, and improving the thermal conductivity and lithium erosion resistance of the ceramic sagger.

The application provides a magnesium-based thermoelectric material and a preparation method and device thereof. The preparation method comprises the following steps: placing reaction raw materials of the magnesium-based thermoelectric material into a yttria-doped zirconia crucible; sealing the yttria-doped zirconia crucible containing the reaction raw materials into a tantalum crucible; sealing the tantalum crucible obtained in the step (2) into a quartz tube; and placing the sealed quartz tube into a rocking growth furnace to perform grain growth and solidification of the magnesium-based thermoelectric material. The preparation method provided by the application can prepare a magnesium-based thermoelectric material with higher performance and large grain size through a high-temperature melting method.

The application discloses an anti-thermal shock alumina fiber reinforced phosphate high-temperature-resistant composite material and a preparation method thereof, and belongs to the technical field of ceramic matrix composites. The material is composed of gradient modified alumina fiber reinforcement, composite phosphate matrix and multi-scale composite filler. The fiber surface is provided with a nano yttrium oxide-yttrium phosphate gradient interface layer, and the matrix is an aluminum phosphate-zirconium phosphate-yttrium oxide composite system. The preparation method comprises fiber degumming, gradient interface modification, slurry preparation, impregnation and curing and microwave sintering. Through gradient interface regulation and composite matrix design, the application solves the problems of poor thermal shock resistance and insufficient high-temperature stability of the existing materials. Tests show that the material has no macroscopic cracking after 10 times of water cooling at 1300 DEG C, the strength retention rate is greater than or equal to 88%, the room temperature bending strength is greater than or equal to 280 MPa, and the material has excellent high-temperature mechanical properties and thermal shock stability, and is suitable for aerospace thermal protection and high-temperature structural parts.

This invention discloses a method for preparing a composite-layer reinforced long-life zirconia sizing nozzle. The method involves uniformly mixing yttrium-stabilized zirconia fine powder, high-purity calcium hexaaluminate fine powder, activated alumina fine powder, and calcium aluminate cement, adding deionized water and stirring until homogeneous, casting into a mold, demolding, and drying to obtain a composite layer preform. The composite layer preform is then isostatically pressed, sintered, cooled, crushed, ball-milled, and sieved to obtain composite layer powder. Activated alumina fine powder, yttrium oxide fine powder, calcium aluminate cement, and the composite layer powder are then uniformly mixed, water is added, and the mixture is rolled to obtain a mud. This mud is then bonded to the inner wall of the nozzle body's inner bore, dried, isostatically pressed, and sintered to obtain the finished product. The composite layer in this invention has the characteristics of being non-wetting and non-reactive with molten steel. The prepared nozzle exhibits excellent thermal shock resistance, erosion resistance, scour resistance, and high strength, improving the cleanliness of molten steel during continuous casting and contributing to the improvement of billet quality.

The application discloses a chromium-doped yttrium oxide crystal material and a structural design method thereof, and belongs to the technical field of inorganic photoelectric functional crystal materials. + The crystal is of R3 trigonal crystal system minimum energy structure, Cr 9‑ The molar doping percentage is 3.125%, occupies a 1b Wyckoff site in a crystal lattice gap, forms [CrO6] 9‑ Regular octahedral coordination, Cr-O bond length is 2.073 angstrom; lattice constants a=b=10.4957 angstrom, c=18.1750 angstrom, a Γ point direct band gap is 3.23 eV, there is no virtual frequency in a phonon spectrum, dynamics is stable, simulated XRD is matched with an experimental spectrum, and Cr-O and Y-O bonds are all ionic bonds. The application realizes accurate determination of a ground state structure, stability verification and electronic property analysis by adopting CALYPSO structure prediction combined with first principle calculation, provides a standardized theoretical design process, and can be used for efficient development of photoelectric functional materials such as solid-state lasers, white light LEDs, solar cells and the like.

Provided is an yttrium oxide film having Vickers hardness of 900 HV or more, in which the half width determined by X-ray diffractometry of the (222) plane of an yttrium oxide crystal is 0.7° or more, the (222) plane is preferentially oriented in a crystal structure of yttrium oxide, and the diffraction intensity of the (222) plane in X-ray diffractometry is twice or more those of other crystal planes. The yttrium oxide film can be formed on the surface of a component for which corrosion resistance, wear resistance, dust generation resistance, etc. are required, and is formed by any one of a PVD method, a CVD method, or an ALD method, particularly by an ion beam assisted vapor deposition method.

The application belongs to the technical field of surface modification, and relates to a preparation method of a flame-retardant ceramic coating based on yttrium oxide concentration regulation, comprising the following steps: dissolving sodium hydroxide and sodium fluoride with a specific mass ratio into a sodium silicate salt electrolyte, and adding a Y2O3 solution with a specific concentration into the electrolyte to obtain a first mixed solution; then placing a magnesium alloy substrate in the first mixed solution, and performing micro-arc oxidation treatment to obtain a magnesium alloy-flame-retardant ceramic composite, and finally obtaining a flame-retardant ceramic coating on the surface of the magnesium alloy substrate through post-processing. The mass ratio of sodium hydroxide and sodium fluoride, the concentration of the sodium silicate salt electrolyte, and the Y2O3 solution with an appropriate concentration are cooperatively regulated to realize accurate regulation of the performance of the flame-retardant coating on the surface of the magnesium alloy, so as to meet the actual application requirements of the flame-retardant performance of the magnesium alloy material for high-temperature key components, and promote the wide application of the magnesium alloy under high-temperature and flammable working conditions.

This application discloses a method for preparing high-strength and high-toughness ZTA ceramics from multi-graded powder, relating to the field of structural ceramic preparation technology. The method includes: preparing raw materials by mixing four-particle-graded ZTA-based powder, yttrium oxide-cerium dioxide composite sintering aid, DMAA gel system, dispersant, initiator, and deionized water in parts by mass; followed by powder pretreatment, gel slurry preparation, casting and curing, degreasing treatment, and three-stage pressureless sintering to obtain the finished ZTA ceramic product. This application achieves close particle packing through a four-particle-graded structure based on the Dingle model, achieves uniform molding using a low-toxicity DMAA gel system, and controls grain growth through a three-stage sintering process, ultimately obtaining high-strength and high-toughness ZTA ceramics suitable for waste incineration power generation, biomedicine, semiconductor packaging, and other fields.

To provide a structural component with a highly durable protective film against plasma. [Solution] The structural member 10 comprises a base material 100 and a protective film 200 covering the surface 110 of the base material 100. The protective film 200 mainly contains yttria, and in the Raman spectrum of the protective film 200 obtained by Raman spectroscopy, 370 cm⁻¹ -1 The half-width of the peak at nearby wavenumbers is 23 cm. -1 That's all.

The application belongs to the technical field of metal surface modification coating, and particularly relates to a metal high-performance coating and a preparation process thereof, wherein the coating comprises, from the surface of a metal substrate outward, a biocompatible bonding layer, a composition and structure gradient transition layer, a main functional heat insulation and anti-adhesion layer, and a surface super-hydrophobic anti-adhesion layer; the biocompatible bonding layer is composed of pure titanium or titanium alloy; the composition of the composition and structure gradient transition layer continuously and gradually changes from (Ti, Al)N or (Ti, Zr)N rich in metal to stoichiometric TiN or (Ti, Al)N along the thickness direction; the main functional heat insulation and anti-adhesion layer is an aluminum oxide (Al2O3) or yttrium oxide stabilized zirconium oxide (YSZ) layer, and the surface of the layer has a micro-nano composite rough structure; the surface super-hydrophobic anti-adhesion layer is a fluorine-containing silane coupling agent layer or a plasma polymerized perfluorocarbon layer, and the surface static water contact angle of the layer is greater than 120°.

The application relates to the technical field of industrial robots, and particularly discloses an industrial robot joint metal protective cover with a high-temperature-resistant coating and a preparation method thereof. The protective cover comprises a metal base body and a high-temperature-resistant coating system formed on the surface of the metal base body. The coating system comprises a bonding layer and a ceramic surface layer from inside to outside. The bonding layer comprises a NiCoCrAlY alloy and yttrium oxide. The ceramic surface layer comprises yttrium-stabilized zirconium, aluminum oxide and cerium dioxide. By optimizing the thickness ratio and material composition of the bonding layer and the ceramic surface layer, and by cooperating with surface pretreatment, flame spraying, laser texturing and plasma spraying and other processes, the problem of insufficient bonding force caused by the difference in the thermal expansion coefficient between the coating and the base body is solved, and the bonding strength of the protective cover in a high-temperature environment is improved.

This invention relates to a method for preparing yttrium oxide with a large specific surface area. The method includes the following steps: S1, dissolving yttrium salt and adding tetramethylammonium hydroxide to precipitate; S2, washing with distilled water and centrifuging to dehydrate; S3, washing with ethanol and dehydrating; S4, adding diethylene glycol monobutyl ether and mixing evenly to form a paste; S5, calcining the paste formed in step S4 at a low temperature to form a powder; S6, adding anhydrous ethanol to the powder obtained in step S5 and ball milling; S7, drying. This invention uses tetramethylammonium hydroxide for precipitation, whose spatial structure reduces agglomeration. After washing, multiple washes with ethanol remove moisture, and then diethylene glycol monobutyl ether solution is added to form a paste, further reducing agglomeration during calcination. The calcination temperature is only 600-750℃, which is energy-saving and environmentally friendly. During ball milling, anhydrous ethanol is added, eliminating moisture during the process and reducing agglomeration. The yttrium oxide prepared by this method has a specific surface area of ​​100-200 m² / g. 2 / g.

This invention relates to an electrostatic chuck and its preparation method, specifically to the semiconductor field. The electrostatic chuck comprises: a first ceramic layer, an electrode layer, and a second ceramic layer sequentially disposed on the working surface of a substrate. The electrode layer comprises, by mass percentage: 80-90% tungsten, with the balance being molybdenum. The second ceramic layer comprises, by mass percentage: 70-80% alumina, 10-15% aluminum nitride, with the balance being yttrium oxide. The electrostatic chuck provided by this invention, by optimizing the composition of the surface layer and electrode layer, can significantly improve the adsorption force of the electrostatic chuck, thereby ensuring the firm adsorption of large-size wafers and ensuring efficient processing.

The present invention provides a nickel-based alloy powder composed of 0.2 to 5% Y2O3 oxide, the remainder of the powder having the following composition: 0.050 to 0.090% C; 14.25 to 15.75% Co; 14.00 to 15.25% Cr; 4.00 to 4.60% Al; 3.90 to 4.50% Mo; 3.00 to 3.70% Ti; 0.012 to 0.020% B; 0 to 0.50% Fe; 0 to 0.060% Zr; 0 to 0.150% Mn; 0 to 0.20% Si; 0 to 0.10% Cu; 0 to 25 ppm S; 0 to 0.5 ppm Bi; 0 to 5 ppm of Ag; 0 to 5 ppm of Pb; 0 to 60 ppm of N2; and 0 to 200 ppm of O; Ni making up the balance of the composition; given that the percentages and ppm mentioned above are relative to the total of the remaining powder. An alloy that can be produced from this powder and a process for producing this alloy from this powder are also proposed. Abstract figure: Figure 2

The application discloses a yttria-corundum-mullite composite material, which comprises the following chemical components in percentage by mass: mullite 34.3%-34.475%, corundum 63.7%-64.025% and yttria 1.5%-2%; the apparent porosity of the composite material is 17.13%-18.03%; the composite material comprises corundum phase, mullite phase and yttrium aluminum garnet phase, and the yttrium aluminum garnet phase is generated by solid phase reaction of yttria and corundum in a high-temperature sintering process; by adding 1.5%-2wt% yttria as a modifier, the bending strength of the composite material is up to 58.53MPa, and the strength is improved by 131.50% compared with that of the corundum-mullite material without adding yttria; the apparent porosity is reduced to 17.13%-18.03%, the bulk density is optimized to 2.4333g / cm3, and the densification degree is greatly improved.

This application relates to a spraying process for a highly corrosion- and wear-resistant yttrium oxide composite coating, aiming to solve the problems of high porosity, poor high-temperature stability, and insufficient wear resistance of existing yttrium oxide coatings. The process includes degreasing and cleaning, pure water immersion, sandblasting roughening, steam and water rinsing, ultrasonic cleaning, pre-drying, plasma spraying, orthogonal experimental parameter optimization, deep ultrasonic cleaning, and final drying and curing. A yttrium oxide and zirconium oxide composite powder is used to form a dense coating under optimized plasma spraying parameters, and high cleanliness is ensured through multi-stage cleaning and clean environment control. Through the above technical solution, this application significantly improves the coating's density, chemical stability, wear resistance, and thermal shock resistance, effectively blocks the penetration of corrosive media, reduces particulate contamination, and meets the stringent requirements of semiconductor etching equipment for long-lasting protective coatings.

The application belongs to the technical field of welding materials, and specifically provides a welding rod for damping alloy, which comprises a welding core and a coating, and the coating comprises the following components in percentage of the total mass of the coating: 8-10% of strontium carbonate, 10-18% of fluorite, 5-6% of sodium fluoride, 5-7% of silicon powder, 12-18% of rutile, 2-3% of atomized ferrosilicon, 5-7% of aluminum oxide, 20-21% of electrolytic manganese, 1-2% of yttrium oxide, and the balance is iron powder. The welding rod for damping alloy has good all-position welding process performance and excellent mechanical properties, the average value of deposited metal-20 DEG C KV2 is greater than 80 J, the weld is beautiful, and the chemical composition, mechanical properties and damping performance of the deposited metal can meet the welding requirements of damping steel.

This application discloses a phosphorus pig iron stabilizer for aluminum electrolysis. The stabilizer has a core-shell structure, comprising an improver as the core, a desulfurizing agent as the first outer shell coated on the improver, and a carbonizing agent as the second outer shell coated on the first outer shell. The improver includes one or more of ferrosilicon, calcium silicon, lanthanum oxide, cerium oxide, yttrium oxide, praseodymium oxide, and neodymium oxide. The phosphorus pig iron stabilizer disclosed in this application can effectively solve the elemental imbalance problem during the reuse of phosphorus pig iron and improve various problems caused by elemental imbalance.

This invention discloses a method for preparing high-density, low-defect yttrium oxide ceramic materials and their applications, comprising the following steps: (1) preparing ceramic blanks by using high-purity yttrium oxide precursor powder through a molding process; (2) heating the ceramic blanks obtained in step (1) to 800-900 ℃ at 1-5 ℃ / min in an oxidizing atmosphere and holding them for 15-30 h; (3) continuing to heat the material obtained in step (2) to 1080-1150 ℃ at 1-5 ℃ / min in an oxidizing atmosphere and holding them for a shorter holding time than in step (2); (4) cooling the material obtained in step (3) with the furnace to avoid thermal stress-induced cracks, thereby obtaining the high-density, low-defect yttrium oxide ceramic material. This invention improves the density and microstructure uniformity of the material, enhances surface chemical stability and defect repair, strengthens bulk crystallinity and thermal shock resistance, reduces the risk of particulate contamination and extends component life, and the process is energy-saving, environmentally friendly and highly operable.

The application belongs to the technical field of ceramics and relates to a low-temperature aging-resistant zirconia ceramic as well as a preparation method and application thereof. Before sintering treatment of a zirconia ceramic body, a vacuum evaporation plating technology is used to form an evaporation layer on the surface of the zirconia ceramic body, and then sintering treatment is performed, so that a zirconia ceramic with a yttrium oxide protective layer is finally obtained; the evaporation layer is a metal yttrium layer or a yttrium oxide layer, and the thickness of the evaporation layer is greater than or equal to 1 nm. Through the evaporation plating technology, a nanoscale yttrium oxide shell layer with a controllable thickness and a dense structure is formed on the outer layer of the zirconia ceramic, and in a hydrothermal aging environment, the dense shell layer can effectively block the erosion of water on yttrium elements in the zirconia matrix, thereby significantly inhibiting the occurrence of low-temperature aging phase change and greatly improving the long-term stability and service life of the zirconia ceramic material.

This invention discloses a rare earth-containing aluminum alloy refining agent and its application method. The aluminum alloy refining agent is composed of aluminum powder, titanium powder, carbon powder, copper oxide powder and yttrium oxide powder, and the molar ratio of aluminum, titanium, carbon, copper oxide and yttrium oxide is (2.0~6.0):(0.5~1.5):(0.5~1.5):(0.2~1.5):(0.01~0.2). The application method includes: step (1) ball milling and mixing aluminum powder, titanium powder, carbon powder, copper oxide powder and yttrium oxide powder to obtain mixed raw material powder; step (2) pressing the mixed raw material powder into shape and drying to obtain aluminum alloy refining agent block; step (3) pressing the dried aluminum alloy refining agent block into aluminum alloy melt for high-temperature self-propagating reaction; step (4) casting using near liquidus temperature casting method to obtain aluminum alloy ingot with significantly refined grain structure. This invention can achieve a fine and uniform equiaxed crystal structure comparable to that of rapid solidification under conventional casting conditions. In-situ particles can also serve as reinforcing phases, playing a role in dispersion strengthening.

The use of selective deposition of silicon nitride can eliminate conventional patterning steps by allowing silicon nitride to be deposited only in selected and desired areas. Using a silicon iodide precursor alternately with a thermal nitrogen source in an ALD or pulsed CVD mode, silicon nitride can be deposited preferentially on a surface such as silicon nitride, silicon dioxide, germanium oxide, SiCO, SiOF, silicon carbide, silicon oxynitride, and low k substrates, while exhibiting very little deposition on exposed surfaces such as titanium nitride, tantalum nitride, aluminum nitride, hafnium oxide, zirconium oxide, aluminum oxide, titanium oxide, tantalum oxide, niobium oxide, lanthanum oxide, yttrium oxide, magnesium oxide, calcium oxide, and strontium oxide.

The application discloses a kind of high sphericity yttrium oxide granulation powder and preparation method, the preparation method includes the following steps: S1, dispersing agent is mixed with deionized water, yttrium oxide powder is added to prepare the slurry with solid content of 30%-45%, slurry is ball milled;S2, the slurry obtained is first spray granulation, and spherical yttrium oxide granulation powder is prepared;S3, spherical yttrium oxide granulation powder is degreased, and intermediate powder without additive is prepared;S4, dispersing agent is mixed with deionized water, and the intermediate powder obtained in S3 is added to prepare the slurry with solid content of 40%-50%, slurry is ball milled;S5, binder and defoaming agent are added in the slurry obtained in S4, and stirring;S6, the slurry prepared in S5 is second spray granulation, and high sphericity yttrium oxide granulation powder is prepared;The application can solve the problem that the sphericity of the yttrium oxide granulation powder prepared by the existing spray granulation is poor, which easily leads to the cracking of green body during forming.

The application provides a composite ceramic core for titanium alloy casting and a preparation method and a removal method thereof. The composite ceramic core comprises a ceramic core base and a coating attached to the surface of the base. Raw materials of the ceramic core base comprise solid powder and a binder. The solid powder comprises, in terms of mass percentage, calcium hydroxide 30-55%, magnesium oxide 29-47.5%, metal aluminum powder 10-15% and zirconium oxide 5-15%. The mass ratio of the solid powder to the binder is 1:0.01-0.05. The coating is a yttrium oxide coating. The composite ceramic core has high bending strength and open porosity, and effectively reduces the hydration reaction occurring in the process of shell dewaxing, thereby preventing the collapse of the core and realizing rapid chemical corrosion core removal.

The application belongs to the technical field of conductive ceramic materials, and particularly relates to a conductive ceramic material and a preparation method and application thereof. According to mass parts, the conductive ceramic material comprises the following components: 79-97 parts of beta-aluminum oxide, 0.5-2 parts of yttrium oxide, 0.7-3 parts of thorium oxide, 1-8 parts of zirconium oxide, 0.5-2 parts of molybdenum dioxide, 0.2-3 parts of copper oxide and 0.1-3 parts of zinc oxide. Due to the introduction of high-activity aluminum oxide nano powder and yttrium oxide, the sintering temperature can be greatly reduced, the energy consumption is reduced, the preparation cost is reduced, the competitiveness is improved, and the application is conducive to popularization.

The application discloses a thermal expansion gradient type composite ceramic body and a preparation method of the composite ceramic body, relates to the technical field of ceramic materials, and realizes the protection of a yttrium-magnesium composite ceramic window base material by preparing yttrium-magnesium composite ceramics with different components and by the different thermal expansion coefficients caused by the different components, so that the purpose of preventing thermal shock cracking is achieved. The thermal expansion gradient type composite ceramic body takes yttria-magnesium oxide with a volume ratio of 1:1 as the base of an infrared window, a yttria-magnesium oxide composite surface layer with a thickness of 0.5-1.0 mm and a lower thermal expansion coefficient is arranged on the surface of the base, the surface layer exerts a compressive stress on the base in the heating process by using the thermal expansion difference, the generation and expansion of surface cracks are inhibited, and the stability and service life of the ceramic structure are improved.

Method for producing a resistive particle sensor (1) for detecting particles in a gas stream, wherein the particle sensor (1) comprises an electrode system (2) of at least two electrodes (3, 4) and at least one semiconducting material (5), wherein the semiconducting material (5) contacts the electrodes (3, 4), wherein the semiconducting material (5) is at least one oxide selected from the group consisting of rare-earth-rare-earth mixed oxides, rare-earth-zirconium mixed oxides, alkaline-earth-zirconium mixed oxides, transition-metal-zirconium mixed oxides, rare-earth-aluminum mixed oxides, alkaline-earth-aluminum mixed oxides, transition-metal-aluminum mixed oxides, rare-earth-titanium mixed oxides, barium-titanium mixed oxides, transition-metal-titanium mixed oxides, rare-earth-indium mixed oxides, Alkaline earth indium mixed oxides, transition metal indium mixed oxides, rare earth zinc mixed oxides, alkaline earth zinc mixed oxides, transition metal zinc oxide mixed oxides, samarium oxide, yttrium oxideTerbium oxide and / or mixtures thereof, comprising, wherein a voltage is applied to the electrodes (3, 4) and the semiconducting material (5) under an atmosphere free of oxidizing and / or reducing agents, the voltage being selected such that at least one metal of the semiconducting material (5) is at least partially reduced or oxidized in the regions of the semiconducting material (5) which contact the electrodes (3, 4), characterized in that both electrodes (3, 4) are connected simultaneously at the same potential relative to the semiconducting material (5).