CN214612163U

CN214612163U - Novel high-thermal-conductivity composite crucible for polycrystalline silicon ingot casting

Info

Publication number: CN214612163U
Application number: CN202120811971.XU
Authority: CN
Inventors: 李健; 谢炎; 高源�
Original assignee: Yantai Hejing Ceramic New Materials Co ltd
Current assignee: Yantai Hejing Ceramic New Materials Co ltd
Priority date: 2021-04-20
Filing date: 2021-04-20
Publication date: 2021-11-05
Anticipated expiration: 2031-04-20

Abstract

The utility model relates to a novel compound crucible of high heat conduction for polycrystalline silicon ingot casting belongs to crucible technical field for the polycrystalline silicon ingot casting, including the crucible body, the crucible body is upper end open-ended cavate structure, graphite alkene-silica composite layer has been laid to the inner chamber bottom of the crucible body, the quartz ceramic structural layer has been laid to graphite alkene-silica composite layer's top. The utility model discloses a novel polycrystalline silicon ingot casting is with high heat conduction composite crucible through add graphite alkene-silicon dioxide combined material layer in the crucible, can strengthen the mechanical properties and the calorifics performance of material effectively, still has fine toughness when making novel composite crucible have higher strength, can reduce the overflow rate of crucible effectively, uses this composite crucible simultaneously can reduce the energy consumption of ingot casting process, improves the quality of polycrystalline silicon crystal, satisfies the market demand.

Description

Novel high-thermal-conductivity composite crucible for polycrystalline silicon ingot casting

Technical Field

The utility model relates to a novel compound crucible of polycrystalline silicon ingot casting especially relates to a novel compound crucible of high heat conduction for polycrystalline silicon ingot casting, and it belongs to crucible technical field for the polycrystalline silicon ingot casting.

Background

In the preparation process of the polycrystalline silicon ingot, a quartz ceramic crucible is an important article which must be adopted in the polycrystalline silicon ingot casting stage, silicon materials are melted in the crucible, crystal grows, annealing and cooling are carried out, the polycrystalline silicon ingot is cast, and the silicon ingot is cut into silicon wafers according to the technical requirements, so that the substrate material for producing and manufacturing the solar cell is obtained.

At present, a quartz ceramic crucible is mainly prepared into a blank body by adopting a slip casting forming mode, and then the blank body is sintered at about 1200 ℃ to obtain the quartz ceramic crucible with the density of about 1.92g/cm³The ceramic crucible of (1). The thermal conductivity of such ceramic crucibles is relatively low, typically only 0.86-0.88W/mK. In the directional solidification stage of the ingot, the heat conductivity is low, the heat dissipation is slow, the difference between the heat dissipation of the side wall and the heat dissipation of the bottom is large, a smooth crystal growth interface is needed for obtaining high-quality ingot polycrystal, and the heat dissipation from the side surface can cause a concave crystal growth interface to seriously affect the quality of the crystal. The material matrix of the ceramic crucible is ceramic, the crystalline phase of the ceramic crucible is crystal and glass body, when the cast polycrystalline silicon is prepared, raw materials are melted, and in the process of crystal growth, the silicon melt is contacted with the crucible for a long time, so that a viscous effect can be generated. Due to the difference in the coefficients of thermal expansion of the two materials, if the silicon material is tightly bonded to the crucible walls, it is likely that crystalline silicon or crucible cracking will cause flooding as the crystal cools.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is: overcomes the defects in the prior art and provides a novel high-heat-conductivity composite crucible for polycrystalline silicon ingot casting.

The utility model provides an above-mentioned technical problem's technical scheme as follows:

the utility model provides a novel compound crucible of high heat conduction for polycrystalline silicon ingot casting, includes the crucible body, the crucible body is upper end open-ended cavate structure, graphite alkene-silica composite layer has been laid to the inner chamber bottom of the crucible body, quartz ceramic structure layer has been laid to graphite alkene-silica composite layer's top.

Furthermore, the thickness of the graphene-silicon dioxide composite material layer is 8-10mm, the thickness of the quartz ceramic structure layer is 5-8mm, and the total thickness of the bottom of the crucible body, the graphene-silicon dioxide composite material layer and the quartz ceramic structure layer is 22-25 mm.

Further, the crucible body is of a quartz ceramic structure.

Furthermore, the crucible body is manufactured by adopting a gel casting forming mode.

Compared with the prior art, the beneficial effects of the utility model are that: by adding the graphene-silicon dioxide composite material layer in the crucible, the composite material has the characteristics of light weight, high strength, good heat conductivity and high temperature resistance, combines the respective advantages of the graphene material and the silicon dioxide, can effectively enhance the mechanical property and the thermal property of the material, enables the novel composite crucible to have high strength and good toughness, and can effectively reduce the overflow rate of the crucible; graphene has very good heat conduction performance, the heat conductivity coefficient of pure defect-free single-layer graphene is as high as 5300W/mK, the carbon material with the highest heat conductivity coefficient is the carbon material at present, when the graphene is used as a carrier, the heat conductivity coefficient can also reach 600W/mK, but the graphene is generally degraded when the graphene is exposed to a high-temperature environment, but a ceramic material has the characteristics of high temperature resistance and fire resistance, the characteristics are very helpful for the high temperature resistance of the graphene, the energy consumption in the ingot casting process can be reduced by using a crucible formed by combining the graphene and the graphene to carry out polycrystalline silicon ingot casting, the quality of polycrystalline silicon crystals in the ingot casting process is improved, and the crucible is suitable for large-scale industrial production.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

In the figure, 1, a crucible body; 2. a quartz ceramic structure layer; 3. a graphene-silica composite layer.

Detailed Description

The principles and features of the present invention will be described with reference to the accompanying fig. 1, wherein the examples are provided only for explaining the present invention and are not intended to limit the scope of the present invention.

A novel high-thermal-conductivity composite crucible for polycrystalline silicon ingot casting comprises a crucible body 1, wherein the crucible body 1 is of a cavity type structure with an opening at the upper end, a graphene-silicon dioxide composite material layer 3 is paved at the bottom of an inner cavity of the crucible body 1, and a quartz ceramic structure layer 2 is paved above the graphene-silicon dioxide composite material layer 3; the crucible base layer 1 is of a quartz ceramic structure.

The thickness of the graphene-silicon dioxide composite material layer 3 is 8-10mm, the thickness of the quartz ceramic structure layer 2 is 5-8mm, and the total thickness of the bottom of the crucible body 1, the graphene-silicon dioxide composite material layer 3 and the quartz ceramic structure layer 2 is 22-25 mm.

Examples

A preparation method of a novel high-thermal-conductivity composite crucible for polycrystalline silicon ingot casting comprises the following steps:

(1) preparing a graphene-silicon dioxide composite material: dissolving graphene oxide in water, performing ultrasonic dispersion to obtain a graphene oxide aqueous solution, wherein the concentration of the graphene oxide aqueous solution is 1mg/ml, and then mixing the graphene oxide aqueous solution with toluene according to a mass ratio of 1: 2, adding toluene in proportion to emulsify to obtain a graphene oxide emulsion; adding the monomer siloxane into the graphene oxide emulsion according to the dosage ratio of 50:1 of the monomer siloxane to the graphene oxide, adjusting the pH value to 9 with ammonia water, stirring, carrying out emulsion polymerization for 6 hours, washing and filtering after the reaction is finished to obtain the graphene-silicon dioxide composite material;

(2) preparing a quartz ceramic crucible: preparing a crucible body 1 through a novel gel-casting forming technology, brushing a layer of graphene-silicon dioxide composite material solution at the bottom of the crucible body 1 after the crucible body 1 is dried, then covering a special cover for compaction to form a graphene-silicon dioxide composite material layer 3, pouring a layer of silicon dioxide slurry above the graphene-silicon dioxide composite material layer, covering the cover for compaction to form a quartz ceramic structure layer 2, demoulding after drying, maintaining and sintering at high temperature.

Analysis of Experimental data

The novel high-thermal-conductivity composite crucible for polycrystalline silicon ingot casting produced in the embodiment is subjected to flexural strength, elastic modulus, thermal conductivity, density and apparent porosity detection, and compared with a common crucible, the comparison result is as follows:

TABLE 1

	Ordinary crucible	High heat conduction composite crucible
			Flexural strength MPa	23	25
Elastic modulus GPa	20	30
			Thermal conductivity W/mK	1.0	1.2
Density g/cm³	1.92	1.90
			Apparent porosity%	12	11

As can be seen from the attached Table 1, the comparative analysis of the high thermal conductivity composite crucible and the common crucible leads to the conclusion that: the high-thermal-conductivity composite crucible produced by the method has stronger flexural strength, larger elastic modulus and thermal conductivity coefficient, lower apparent porosity and density and longer service life.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. The utility model provides a novel compound crucible of high heat conduction for polycrystalline silicon ingot casting, includes the crucible body (1), the crucible body (1) is upper end open-ended cavate structure, its characterized in that: the crucible is characterized in that a graphene-silicon dioxide composite material layer (3) is paved at the bottom of an inner cavity of the crucible body (1), and a quartz ceramic structure layer (2) is paved above the graphene-silicon dioxide composite material layer (3).

2. The novel high-thermal-conductivity composite crucible for the polycrystalline silicon ingot casting according to claim 1, is characterized in that: the thickness of the graphene-silicon dioxide composite material layer (3) is 8-10mm, the thickness of the quartz ceramic structure layer (2) is 5-8mm, and the total thickness of the bottom of the crucible body (1), the graphene-silicon dioxide composite material layer (3) and the quartz ceramic structure layer (2) is 22-25 mm.

3. The novel high-thermal-conductivity composite crucible for the polycrystalline silicon ingot casting according to claim 1, is characterized in that: the crucible body (1) is of a quartz ceramic structure.

4. The novel high-thermal-conductivity composite crucible for the polycrystalline silicon ingot casting according to claim 1, is characterized in that: the crucible body (1) is made by adopting a gel-casting molding mode.