Large-size hollow carbon-ceramic composite material and application

Abstract

The present application relates to a kind of large size hollow carbon ceramic composite material and application, belong to photovoltaic and semiconductor device preparation technical field.The present application first adopts outer wall slotting then cooperates purification, densification, siliconization process to prepare high-quality large size hollow carbon ceramic composite material.The carbon ceramic composite material obtained in the present application density is controllable between 1.8~2.6g / cm 3 , all impurities total content is not more than 200PPM, air tightness detection leakage rate is less than 3kPa / min;And on the same product, the fluctuation of the density of each area is less than or equal to 0.1g / cm 3 , and on the slot surface, the fluctuation of the density is less than or equal to 0.05g / cm 3 , even can be less than or equal to 0.03g / cm 3 .The preparation process of the present application is simple and controllable, and the performance of the obtained product is superior, which is convenient for large-scale application.

Description

TECHNICAL FIELD

[0001] The application relates to a large-size hollow carbon-ceramic composite material and application, and belongs to the technical field of photovoltaic and semiconductor device preparation. BACKGROUND

[0002] Graphite or silicon carbide cylindrical or tubular parts are usually used in the production process of photovoltaic and semiconductor devices. In addition to high temperature resistance, these parts also require high purity, high density, and resistance to airflow or powder erosion. With the development of preparation technology in the field of photovoltaic and semiconductor, the size of high-temperature parts is getting larger and larger, and the diameter of some parts exceeds 600 mm. When graphite is used to process large-size cylindrical parts, the material utilization rate is low, and the graphite has poor thermal shock resistance and is prone to thermal cracking failure during use, resulting in high use cost. The preparation cost of large-size silicon carbide cylinders is high, the thermal shock resistance is poor, and the same thermal cracking failure is prone to occur during use, resulting in high application cost. Therefore, it is necessary to design and develop a high-purity, high-density, and high-strength carbon-ceramic composite cylindrical or tubular part to meet the cost reduction and efficiency improvement needs of the photovoltaic and semiconductor industry.

[0003] Currently, there is almost no report on the preparation of high-quality large-size hollow carbon-ceramic composite materials by adopting the process of slotting the outer wall and then cooperating with the purification, densification, and siliconization process. SUMMARY

[0004] The present application overcomes the shortcomings of the prior art and first adopts the process of slotting the outer wall and then cooperating with the purification, densification, and siliconization process to prepare high-quality large-size hollow carbon-ceramic composite materials.

[0005] The preparation methods of carbon-ceramic composite cylindrical or tubular parts mainly include chemical vapor deposition, impregnation pyrolysis, and molten silicon infiltration, etc. Long-term practice has found that the parts prepared by these methods all have the problem of uneven density of carbon matrix and silicon carbide matrix, especially: the larger the diameter, the greater the circumferential density gradient; the longer the tube, the greater the axial density gradient. The main reason is that the uneven distribution of carbon source gas and silicon source liquid in the circumferential and axial directions of the part during high-temperature preparation causes the problem.

[0006] The present application provides a large-size hollow carbon-ceramic composite material, which is prepared by the following steps:

[0007] Step 1

[0008] One layer of carbon fiber cloth and one layer of carbon fiber web are taken as one unit layer, and the carbon fiber cloth and the carbon fiber web are stacked in cycles; then needle punching is adopted to obtain a carbon fiber preform; the carbon fiber preform is cylindrical or tubular; the diameter or equivalent diameter of the carbon fiber preform is greater than 600 mm and the height is greater than 500 mm.

[0009] Step 2

[0010] The obtained carbon fiber preform is subjected to a first purification under a protective atmosphere, the purification temperature is 1800-2600°C, the purification time is equal to or greater than 2h, and the atmosphere is selected from one of a vacuum atmosphere, a freon atmosphere, an H2 atmosphere, and an ammonia atmosphere, preferably a freon atmosphere;

[0011] Step 3

[0012] The carbon fiber preform after the first purification is subjected to a carbon densification treatment to a density of 0.7-1.4 g / cm 3 , preferably 0.9-1.3 g / cm 3 , to obtain a first densified carbon fiber preform;

[0013] Step 4

[0014] The first densified carbon fiber preform is subjected to machining to form grooves on the outer wall of the first densified carbon fiber preform to obtain a grooved carbon fiber preform, the depth of the grooves is not more than 1 / 2 of the wall thickness, preferably 1 / 5-1 / 4 of the wall thickness, the distance between two adjacent grooves is ≥5 mm, preferably 10-200 mm, preferably 50-100 mm, and more preferably 60-80 mm, and the area of the grooves in the projection perpendicular to the outer wall of the carbon fiber preform is 5-25% of the entire projected area, preferably 8-20%.

[0015] Step 5

[0016] The grooved carbon fiber preform is subjected to a purification treatment to obtain a purified grooved carbon fiber preform, the purification temperature is 1800-2600°C, the purification time is equal to or greater than 2h, and the atmosphere is selected from one of a vacuum atmosphere, a freon atmosphere, an H2 atmosphere, and an ammonia atmosphere, preferably a freon atmosphere;

[0017] Step 6

[0018] The purified grooved carbon fiber preform is subjected to carbon densification to 1.2-1.6 g / cm 3 , to obtain a preform to be ceramized;

[0019] Step 7

[0020] The preform to be ceramized is subjected to a ceramization treatment to obtain a product, the ceramization treatment includes at least one of trichloromethylsilane gas chemical vapor deposition, polycarbosilane impregnation pyrolysis, and molten silicon infiltration, and the density of the product is 1.6-2.6 g / cm 3 , preferably 1.9-2.3 g / cm 3 .

[0021] As preferred, in step 1, the carbon fiber cloth is selected from at least one of unidirectional cloth, plain cloth, twill cloth or satin cloth, preferably plain cloth.

[0022] As preferred, in step 1, the carbon fiber preform density is controlled to be 0.3-0.7 g / cm 3 , preferably 0.4-0.6 g / cm 3 . The mass ratio of the carbon cloth and the carbon fiber web is controlled to be (1-10):1, preferably (3.5-4.5):1.

[0023] The carbon fiber preform is tubular; the outer diameter of the tubular carbon fiber preform is greater than 800 mm and the height is greater than 600 mm.

[0024] In step 2, the purification temperature is preferably 2100-2400℃, further optimized to 2400℃, and the time is preferably 3-5 h; the atmosphere can be vacuum, freon, H2 atmosphere, ammonia atmosphere, preferably freon atmosphere.

[0025] In step 3, the carbon densification treatment can adopt carbon-containing organic gas chemical vapor deposition, resin or pitch impregnation carbonization process, preferably natural gas chemical vapor deposition densification, or pitch impregnation carbonization densification, and the density is increased to 0.7-1.4 g / cm 3 , preferably 0.9-1.3 g / cm 3 .

[0026] In step 4, the groove processing adopts turning processing. The depth of the groove is not more than 1 / 2 of the wall thickness, preferably 1 / 5-1 / 4 of the wall thickness. The groove opening can be square, semicircular, waist-shaped, trapezoidal, arc-shaped, etc., preferably semicircular groove.

[0027] In the scheme designed by the present application, the inner wall can also be grooved.

[0028] In the scheme designed by the present application, the inner wall grooving adopts a staggered manner with the outer wall.

[0029] The spiral groove can also be used in the present application.

[0030] The area occupied by the projection groove is 10-12% of the entire projection area.

[0031] The grooved product has a large specific surface area, so that the process gas or liquid can be more fully contacted with the product for reaction. Secondly, the surface groove will block the process gas or liquid flow on the product surface, so that it can fully penetrate into the product for reaction. At the same time, the grooving provides a diffusion channel in thickness for the process gas and liquid, so that it can better penetrate into the product for reaction.

[0032] In step 5, the purification is carried out by high-temperature treatment, the purification temperature is 2100-2400℃, preferably 2400℃, the time is greater than 2h, preferably 3-5h, and the atmosphere is one of vacuum, freon, H2 atmosphere, ammonia atmosphere, preferably freon atmosphere.

[0033] In step 6, the carbonization process can adopt chemical vapor deposition of carbon-containing organic gas, resin or pitch impregnation carbonization process, preferably natural gas chemical vapor deposition densification, or pitch impregnation carbonization densification, and the density is increased to 1.2-1.6g / cm 3 , preferably 1.3-1.5g / cm 3 .

[0034] In step 7, the ceramicization process can adopt trichloromethylsilane gas chemical vapor deposition, polycarbosilane impregnation pyrolysis and molten silicon infiltration process, preferably molten silicon infiltration process, the silicon infiltration temperature is 1450-2100℃, preferably 1600-1900℃, further preferably 1600℃, the molten infiltration time is 1-14h, preferably 2-3h, and the furnace can be under negative pressure or micro-positive pressure, preferably negative pressure. The silicon carbide is densified to 1.8-2.6g / cm 3 , preferably 1.9-2.3g / cm 3 .

[0035] After the ceramicization treatment, the second purification can be carried out; the second purification temperature is 1800-2600℃, preferably 2200-2400℃, further preferably 2400℃, the time is greater than 2h, preferably 3-5h, and the atmosphere is one of vacuum, freon, H2 atmosphere, ammonia atmosphere, preferably freon atmosphere.

[0036] The present application opens a plurality of circumferential grooves at the appropriate position of the outer wall of the cylindrical and tubular part. The surface grooves will be beneficial to improve the process gas and liquid residence time and uniform distribution, improve the product uniformity and density. At the same time, a high-strength silicon carbide ceramic layer can be formed in the groove, which can strengthen the part and improve the rigidity of the part.

[0037] The large-size carbon ceramic composite material prepared by the present application has a density of 1.8-2.6g / cm 3 , and the total content of all impurities is not more than 200PPM, and the air tightness detection leakage rate is less than 3kPa / min. The strength of the carbon ceramic part prepared by the process is more than 2 times that of the same size graphite or silicon carbide part.

[0038] After optimization, the density fluctuation of each region of the product of the present application is less than or equal to 0.1g / cm 3 , and the density fluctuation on the slotted surface is less than or equal to 0.05g / cm 3 , and even less than or equal to 0.03g / cm 3 .

[0039] The present application first discovers that adopting proper slotting on the wall (especially on the outer wall) can not only solve the uniformity problem of large-size carbon-tube composite materials, but also improve the mechanical properties thereof.

[0040] The large-size carbon-tube composite material prepared by the present application is used as a photovoltaic and / or semiconductor device. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 is a schematic view of a large-size carbon-tube composite material prepared by the present application. Figure 1 Figure 2 is a schematic view of a slotted cylinder with semicircular notches.

[0042] Figure 3 is a schematic view of a slotted cylinder with square notches. Figure 2 Figure 4 is a schematic view of a slotted cylinder with waist-shaped notches.

[0043] Figure 3 Figure 5 is a schematic view of a non-solid bottom bucket with semicircular notches.

[0044] Figure 6 is a schematic view of a solid bottom bucket with semicircular notches. Figure 4 Figure 7 is a schematic view of a large-size carbon-tube composite material prepared by the present application.

[0045] Figure 5 Figure 8 is a schematic view of a large-size carbon-tube composite material prepared by the present application. DETAILED DESCRIPTION

[0046] Example 1

[0047] Step 1

[0048] A carbon fiber preform was prepared by stacking one layer of plain weave carbon fiber cloth and one layer of carbon fiber webbing as a unit layer, and then needling the unit layer to obtain the carbon fiber preform. The density of the prepared carbon fiber preform was controlled to be 0.4 g / cm 3 , and the mass ratio of carbon cloth to carbon fiber webbing was controlled to be 3.5:1. The carbon fiber preform was a circular tube with an outer diameter of 1200 mm, an inner diameter of 1150 mm, and a height of 1180 mm.

[0049] Step 2

[0050] The carbon fiber preform obtained in step 1 was purified by high-temperature treatment, the purification temperature was 2100°C, the time length was 3h, and the atmosphere was freon atmosphere.

[0051] Step 3

[0052] The purified carbon fiber preform obtained in step 2 was densified by natural gas chemical vapor deposition, and the density was increased to 0.9 g / cm 3 .

[0053] Step 4

[0054] ​​The grooving is performed by turning on the outer wall of the carbon fiber preform after the first densification (i.e. the product obtained in step 3), to obtain a grooved carbon fiber preform; the depth of the groove is 1 / 5 of the wall thickness, i.e. the radius of the semicircle is 10 mm; the distance between two adjacent grooves is 80 mm; the projection of the groove on the outer wall of the carbon fiber preform is 11% of the entire projected area.

[0055] Step 5

[0056] The grooved carbon fiber preform is subjected to a purification treatment to obtain a purified grooved carbon fiber preform; the purification temperature is 2100℃, the duration is 3h, and the atmosphere is freon atmosphere.

[0057] Step 6

[0058] The purified grooved carbon fiber preform is subjected to a chemical vapor deposition densification with natural gas to 1.3g / cm 3 ; to obtain a preform to be ceramicized;

[0059] Step 7

[0060] The preform to be ceramicized is subjected to a ceramicization treatment to obtain a product; the ceramicization treatment process is a silicon infiltration process.

[0061] During the silicon infiltration, the silicon infiltration temperature is 1600℃, the infiltration time is 2h, and the furnace can be under negative pressure.

[0062] After the silicon infiltration, a re-purification process is adopted, the purification temperature is 2100℃, the duration is 2h, and the atmosphere is freon atmosphere.

[0063] The densities of the top, middle and bottom of the outer wall of the obtained product are 2.11g / cm 3 , 2.09g / cm 3 , and 2.12g / cm 3 , respectively; the densities of the top, middle and bottom of the inner wall are 2.08g / cm 3 , 2.11g / cm 3 , and 2.12g / cm 3

[0064] The total content of all impurities is not more than 200PPM, and the leakage rate of the air tightness test is less than 3kPa / min. The carbon ceramic component prepared by the process has a bending strength of 125MPa, which is more than 2 times that of a graphite or silicon carbide component of the same size.

[0065] Example 2

[0066] The other conditions are the same as in Example 1, except that:

[0067] The grooving is processed by turning, and square grooves are formed on the outer wall of the carbon fiber preform after the first densification (i.e. the product obtained in step 3), to obtain a grooved carbon fiber preform; the depth of the groove is 1 / 3 of the wall thickness (i.e. the side length of the square is 16.7 mm); the distance between two adjacent grooves is 60 mm; and the area occupied by the groove in the projection perpendicular to the outer wall of the carbon fiber preform is 15% of the entire projected area.

[0068] The densities of the top, middle and bottom of the outer wall of the obtained product are 2.21 g / cm 3 , 2.23 g / cm 3 , and 2.25 g / cm 3 , respectively; and the densities of the top, middle and bottom of the inner wall are 2.20 g / cm 3 , 2.19 g / cm 3 , and 2.27 g / cm 3

[0069] The total content of all impurities is not more than 200 PPM, and the leakage rate in the air tightness test is less than 3 kPa / min. The carbon ceramic part prepared by the process has a bending strength of 108 MPa, which is more than 2 times that of a graphite or silicon carbide part of the same size.

[0070] Example 3

[0071] The other conditions are the same as in Example 1, except that:

[0072] The grooving is processed by turning, and trapezoidal grooves are formed on the outer wall of the carbon fiber preform after the first densification (i.e. the product obtained in step 3), to obtain a grooved carbon fiber preform; the depth of the groove is 1 / 5 of the wall thickness (i.e. the height of the trapezoid is 10 mm, the longer base is 10 mm, and the shorter base is 9 mm); the distance between two adjacent grooves is 80 mm; and the area occupied by the groove in the projection perpendicular to the outer wall of the carbon fiber preform is 11% of the entire projected area.

[0073] The densities of the top, middle and bottom of the outer wall of the obtained product are 2.05 g / cm 3 , 2.08 g / cm 3 , and 2.10 g / cm 3 , respectively; and the densities of the top, middle and bottom of the inner wall are 2.03 g / cm 3 , 2.11 g / cm 3 , and 2.09 g / cm 3

[0074] The total content of all impurities is not more than 200 PPM, and the leakage rate in the air tightness test is less than 3 kPa / min. The carbon ceramic part prepared by the process has a bending strength of 110 MPa, which is more than 2 times that of a graphite or silicon carbide part of the same size.

[0075] Example 4

[0076] Other conditions are consistent with Example 1, except that:

[0077] The grooving is performed by turning on the outer wall of the carbon fiber preform after the first densification (i.e. the product obtained in step 3); the depth of the groove is 1 / 10 of the wall thickness (i.e. the radius of the semicircle is 5 mm); the distance between two adjacent grooves is 80 mm; the projection area occupied by the groove on the projection perpendicular to the outer wall of the carbon fiber preform is 5.5% of the entire projection area.

[0078] The densities of the top, middle and bottom of the outer wall of the obtained product are 1.95 g / cm 3 , 2.02 g / cm 3 , 2.02 g / cm 3 , respectively; the densities of the top, middle and bottom of the inner wall are 1.92 g / cm 3 , 2.01 g / cm 3 , 2.07 g / cm 3

[0079] The total content of all impurities is not more than 200 PPM, and the leakage rate of the air tightness test is less than 3 kPa / min. The carbon ceramic part prepared by the process has a bending strength of 98 MPa, which is more than 2 times that of the same size graphite or silicon carbide part.

[0080] Example 5

[0081] Other conditions are consistent with Example 1, except that: the heat treatment temperature in step 5 is 2400°C, the time is 5h, and the flowing fluorine is used.

[0082] The densities of the top, middle and bottom of the outer wall of the obtained product are 2.12 g / cm 3 , 2.15 g / cm 3 , 2.18 g / cm 3 , respectively; the densities of the top, middle and bottom of the inner wall are 2.11 g / cm 3 , 2.09 g / cm 3 , 2.2 g / cm 3

[0083] The total content of all impurities is not more than 150 PPM, and the leakage rate of the air tightness test is less than 3 kPa / min. The carbon ceramic part prepared by the process has a strength of 132 MPa, which is more than 2 times that of the same size graphite or silicon carbide part.

[0084] Comparative Example 1

[0085] Other conditions are consistent with Example 1, except that: step 4 is omitted;

[0086] The densities of the outer wall top, middle and bottom of the product are 1.75 g / cm 3 , 1.98 g / cm 3 , and 2.25 g / cm 3 , respectively; the densities of the inner wall top, middle and bottom are 1.95 g / cm 3 , 1.81 g / cm 3 , and 2.29 g / cm 3

[0087] The total content of all impurities is not more than 200 PPM, and the leakage rate of the air tightness test is 82 kPa / min. The carbon ceramic part prepared by the process has a bending strength of 79 MPa.

[0088] Comparative Example 2

[0089] The other conditions are the same as in Example 1, except that:

[0090] The grooving is performed by turning on the outer wall of the carbon fiber preform after the first densification (i.e., the product obtained in step 3); the depth of the groove is 2 / 3 of the wall thickness; the distance between two adjacent grooves is 3 mm; and the area occupied by the groove on the projection perpendicular to the outer wall of the carbon fiber preform is 1% of the entire projected area.

[0091] The densities of the outer wall top, middle and bottom of the product are 1.85 g / cm 3 , 1.96 g / cm 3 , and 2.12 g / cm 3 , respectively; the densities of the inner wall top, middle and bottom are 1.92 g / cm 3 , 2.12 g / cm 3 , and 2.18 g / cm 3

[0092] The total content of all impurities is not more than 200 PPM, and the leakage rate of the air tightness test is 18 kPa / min. The carbon ceramic part prepared by the process has a bending strength of 87 MPa.

Claims

1. A large-size hollow carbon-ceramic composite material, characterized in that, Prepared by the following steps: Step 1 A carbon fiber preform is obtained by cyclically stacking a layer of carbon fiber cloth and a layer of carbon fiber mesh as a unit layer; then needle punching and weaving are used; the carbon fiber preform is one of the following: a barrel-shaped, tubular or cylindrical container, a support crucible, an inner lining, or a conveying pipe; the diameter or equivalent diameter of the carbon fiber preform is greater than 600 mm and the height is greater than 500 mm. Step 2 The obtained carbon fiber preform was subjected to a first purification under a protective atmosphere at a temperature of 1800℃~2600℃ for at least 2 hours. The atmosphere was selected from one of the following: vacuum, Freon, H2, or ammonia. Step 3 The carbon fiber preform after the first purification was subjected to carbon densification treatment to a density of 0.7~1.4 g / cm³. 3 ; to obtain the carbon fiber preform after the first densification; Step 4 The carbon fiber preform after the first densification is machined by slotting the outer wall of the preform to obtain a slotted carbon fiber preform; the depth of the slot does not exceed 1 / 2 of the wall thickness; the distance between two adjacent slots is ≥5mm; a projection is made perpendicular to the outer wall of the carbon fiber preform, and the area occupied by the slot on the projection is 5-25% of the total projection area; Step 5 The grooved carbon fiber preform was purified to obtain a purified grooved carbon fiber preform; the purification temperature was 1800℃~2600℃; the purification time was greater than or equal to 2 hours; the atmosphere was selected from one of the following: vacuum atmosphere, Freon atmosphere, H2 atmosphere, and ammonia atmosphere. Step 6 The purified slotted carbon fiber preform was carbon densified to 1.2~1.6 g / cm³. 3 ; Obtain the preform to be ceramicized; Step 7 The preform to be ceramicized undergoes a ceramicization treatment to obtain the product; the ceramicization treatment includes at least one of trichloromethylsilane gas chemical vapor deposition, polycarbosilane impregnation pyrolysis, and melt infiltration; the density of the product is 1.6~2.6 g / cm³. 3 .

2. The large-size hollow carbon ceramic composite material according to claim 1, characterized in that: In step 1, the carbon fiber cloth is selected from at least one of unidirectional cloth, plain weave cloth, twill weave cloth or satin weave cloth.

3. The large-size hollow carbon ceramic composite material according to claim 1, characterized in that: In step 1, the density of the carbon fiber preform is controlled at 0.3~0.7 g / cm³. 3 The mass ratio of carbon cloth to carbon fiber mesh is controlled between (1~10):

1.

4. The large-size hollow carbon ceramic composite material according to claim 1, characterized in that: The carbon fiber preform is tubular; the outer diameter of the tubular carbon fiber preform is greater than 800 mm and the height is greater than 600 mm.

5. The large-size hollow carbon ceramic composite material according to claim 1, characterized in that: In step 2, the purification temperature is 2100~2400℃, the time is 3~5h, and the atmosphere is selected from one of vacuum atmosphere, Freon atmosphere, H2 atmosphere, and ammonia atmosphere; In step 3, the carbon densification treatment employs carbon-containing organic gas chemical vapor deposition, resin or asphalt impregnation carbonization processes to increase the density to 0.7~1.4 g / cm³. 3 .

6. The large-size hollow carbon ceramic composite material according to claim 1, characterized in that: In step 4, the groove is machined by turning; the depth of the groove does not exceed 1 / 2 of the wall thickness; the groove opening is one of the following: square, semi-circular, waist-shaped, trapezoidal, or arc-shaped; the area occupied by the groove on the projection is 9-13% of the total projection area.

7. The large-size hollow carbon ceramic composite material according to claim 1, characterized in that: In step 5, the purification process is carried out at high temperature, with a purification temperature of 2100~2400℃ and a duration of more than 2 hours. The atmosphere is one of vacuum atmosphere, Freon atmosphere, H2 atmosphere, or ammonia atmosphere. In step 6, the carbonization process employs either natural gas chemical vapor deposition (CVD) or asphalt impregnation and carbonization to increase the density to 1.2–1.6 g / cm³. 3 ; Step 7 involves a ceramicization process using trichloromethylsilane gas chemical vapor deposition, polycarbosilane impregnation and pyrolysis, and fused silicon infiltration. The fused silicon infiltration process is carried out at a silicon infiltration temperature of 1450℃~2100℃, with a melting time of 1h~14h, and under negative pressure within the furnace. The silicon carbide density is increased to 1.8~2.6 g / cm³. 3 .

8. The large-size hollow carbon ceramic composite material according to claim 7, characterized in that: After ceramicization, the material is purified again. The temperature for the second purification is 1800℃~2600℃, the duration is greater than 2 hours, and the atmosphere is one of vacuum atmosphere, Freon atmosphere, H2 atmosphere, or ammonia atmosphere.

9. A large-size hollow carbon ceramic composite material according to any one of claims 1-7, characterized in that: The resulting carbon-ceramic composite material has a density of 1.8~2.6 g / cm³. 3 The total content of all impurities shall not exceed 200 PPM, and the leakage rate in the airtightness test shall be less than 3 kPa / min; furthermore, the density fluctuation in different areas of the same product shall be less than or equal to 0.1 g / cm³. 3 Furthermore, the density fluctuation on the grooved surface is less than or equal to 0.05 g / cm³. 3 .

10. The application of a large-size hollow carbon-ceramic composite material as described in any one of claims 1-7, characterized in that: The large-size carbon-ceramic composite material is used as a photovoltaic and / or semiconductor device.

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