CN102677168A - Thermal-field-adjustable furnace for growing crystals through kyropoulos method - Google Patents
Thermal-field-adjustable furnace for growing crystals through kyropoulos method Download PDFInfo
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- CN102677168A CN102677168A CN2011100610615A CN201110061061A CN102677168A CN 102677168 A CN102677168 A CN 102677168A CN 2011100610615 A CN2011100610615 A CN 2011100610615A CN 201110061061 A CN201110061061 A CN 201110061061A CN 102677168 A CN102677168 A CN 102677168A
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Abstract
The invention provides a thermal-field-adjustable furnace for growing crystals through a kyropoulos method and belongs to the technical field of crystal growing devices. Due to the fact that an upper thermal insulation layer is connected to an upper thermal insulation layer lifting device, the position of the upper thermal insulation layer can be adjusted by means of the lifting device, then radiation boundary conditions of a crucible and materials can be adjusted, and accordingly a thermal field can be adjusted timely and efficiently. Additionally, combined with means of cooling water volume adjustment, lifting and rotation of seed rods, temperature reduction and the like, the capacity for adjusting and controlling the thermal field of the system can be greatly improved, flexible and effective adjustment can be performed according to different needs for the thermal field of crystal growth in different stages, difference between different devices or between different furnace times of a device or between different technical processes of a furnace and other changed conditions such as feeding volume and environment conditions, and quality and yield of the crystals can be greatly improved. Besides, the thermal-field-adjustable furnace effectively improves stability and repeatability of the process and is particularly suitable for industrialized production of large sapphire crystals.
Description
Technical field
The present invention relates to LED substrate level sapphire crystal growth stove manufacturing technology field, particularly a kind of with the adjustable kyropoulos crystal growth furnace structure of thermal field.
Background technology
Photodiode (Light Emitting Diode; LED) have long, power consumption of life-span less, advantage that volume is little, response is fast, the anti-low temperature of antidetonation, pollution are little etc. gives prominence to; Its Application Areas is very wide, and market potential is huge, is called as " revolution again on the human illumination history ".The LED substrate material has important relationship to its performance and cost; The mechanical property, thermal property, optical property, mechanical property and the chemicalstability that have unique crystalline network, excellence because of sapphire crystal; Become the ideal substrate materials such as GaN semiconductor light-emitting-diode of practical application, account for substrate market more than 90%.In addition, sapphire crystal is widely used in many fields of science and technology, national defence and civilian industry because of its excellent comprehensive performances.
At present, the growth method of sapphire crystal mainly contains crystal pulling method, the guided mode method; The terraced method of temperature, heat-exchanging method and kyropoulos etc., wherein kyropoulos is big with its size; Quality is high, and perfection of crystal is good, and cost is low; But numerous advantages such as in-situ annealing become the main flow growth method of substrate level sapphire crystal, account for more than 70%.Processes such as kyropoulos growing crystal step mainly comprises melt, stabilizes, sows, shouldering, isodiametric growth, ending, annealing cooling; Wherein sow with the shouldering stage be most important and critical step, will directly determine crystal mass, integrity and yield rate, but the distinctive little thermograde of kyropoulos cause this two step very the difficulty; In addition; Disadvantages such as this method growth cycle is long, and diameter is restive, and only the long brilliant process of early growth period is visual; Thereby, kyropoulos stabilization of equipment performance and repeatability are had relatively high expectations.
Conventional kyropoulos crystal growing furnace mostly adopts Russia, Ukraine's technology, and thermal field is made up of squirrel-cage heating element of tungsten and tungsten heat shielding.These characteristics have the furnace inner environment cleaning, are difficult for polluting crystal, are prone to reach very high advantages such as vacuum, and the tungsten heat shielding relies on thermal radiation to reach heat insulation effect, and thermal inertia is poor; And tungsten and molybdenum material shape and surface appearance directly influence heat insulation effect, and tungsten and molybdenum material high temperature is yielding, and volatile matter directly influences heat insulation effect attached to the tungsten surface in the stove, cause thermal field repeatability less stable.Between the different kyropoulos crystal growing furnaces; Thermal field all changes between the different heats of same exactly kyropoulos crystal growing furnace; Technology is especially sowed and the shouldering stage becomes very complicated, process consistency is poor, and is very big to people's dependency; Occur variety of issue easily, directly influence yield rate.
In the kyropoulos crystal growing process, along with crystalline constantly carries out, crystal weight increases; Melt weight reduces, and the final condition of its thermal field constantly changes, and different steps is different to the requirement of thermal field; The general bulb crystal growing furnace of thinking of a way can't in time satisfy the requirement of the crystallization thermal field of different steps; Influence crystallization condition, therefore, crystal mass, size and yield rate all are greatly affected.
In addition; Different raw materials density is different; The not equal factor of, charging method different like the broken grain mixed ratio often causes the charge of the different heats of same crucible to change; Thereby liquid level position changes after the fusing, and the required thermal field environment of crystal structure changes thereupon, and arts demands such as corresponding inoculation, shouldering are made corresponding adjustment.
The means of present kyropoulos crystal growing furnace thermal field regulation and control mainly contain that cooling water inflow is regulated, seed crystal lifts with rotate, means such as cooling; It is very narrow that these means are regulated variable ranges, can only the passive adaptation thermal field, and can't initiatively adjust thermal field in time; Adjustment relatively lags behind; Can not in time tackle for above-mentioned environmental change complicated and changeable, yield rate is lower, is difficult to adapt to industrialized requirement.
Summary of the invention
The objective of the invention is provides a kind of kyropoulos crystal growing furnace that can adjust thermal field flexibly to the existing limited weak point of kyropoulos crystal growing furnace control measures.
The kyropoulos crystal growing furnace that a kind of thermal field of the present invention is adjustable mainly comprises thermal insulation layer lifting device (1), body of heater (2), water cooled electrode (3), vacuum pipe (4), heating element (5), crucible (6), crucible support system (9), following thermal insulation layer (10), side thermal insulation layer (11), goes up thermal insulation layer (13) vision slit (15) etc.Last thermal insulation layer lifting device (1) links to each other with last thermal insulation layer (13); The inside of heating element (5) thermal insulation layer (10), side thermal insulation layer (11), last thermal insulation layer (13) in crucible (6) outside and under being positioned at; Crucible (6) is positioned on the crucible support system (9); Body of heater (2) is provided with vision slit (15) and is convenient to observe crystal (7), melt (8), seed crystal (12), seed rod (14), seed rod (14) through the rotation and pulling apparatus (16) but oscilaltion and rotation.Last thermal insulation layer (13) connects through the last thermal insulation layer lifting device (1) that is fixed on the body of heater; Its position all can be adjustable continuously in position and speed in the 0-100mm altitude range of crucible upper limb position; Make the residing diffusing final condition of crucible and material change, thereby realize that thermal field is adjustable.Last thermal insulation layer (13) top layer is to be processed by the thick refractory metal plate of one deck 1-5mm; It is connected with the tungsten thermal insulation layer that 5-20 layer thickness 0.3-2.0mm does not wait down; Bottom is molybdenum sheet or the tungsten sheet of a thickness at 2-20mm, and each layer refractory metal or tungsten sheet all have the finedraw that staggers each other to reduce high temperature deformation.Through adjusting the different of thermal insulation layer (13) position height and rising or falling speed, thereby make crucible and the residing heat radiation final condition of material change, thereby can effectively adjust thermal field.
Through moving of last thermal insulation layer, regulate the lifting and rotate of seed rod in conjunction with original cooling water inflow; Means such as cooling, the ability of system regulation thermal field is strengthened greatly, and the difference that can be directed against between distinct device, the different heats of same equipment and the same heat different process process is made flexibly rapidly and effectively adjustment; Improve yield rate greatly; The stability of technology and repeated helps large size, particularly the industrialization production of large size sapphire crystal.
Description of drawings
Fig. 1 is the structural representation when thermal insulation layer is in extreme lower position in the present invention;
Fig. 2 be in the present invention thermal insulation layer apart from the crucible upper edge structural representation during certain altitude.
Wherein:
1. go up thermal insulation layer 14. seed rods 15. vision slits 16. rotation and pulling apparatus on 10. times thermal insulation layers of thermal insulation layer lifting device 2. bodies of heater, 3. water cooled electrode 4. vacuum pipes, 5. heating element 6. crucibles, 7. crystal 8. melts, 9. crucible support systems, 11. side thermal insulation layers, 12. seed crystals 13.
Embodiment
Detailed process below in conjunction with sapphire crystal growth is explained as follows:
The high purity aluminium oxide raw material that weighs up weight is packed in the crucible (6); After seed crystal (12) is installed is finished, build thermal insulation layer (13), through rotation and pulling apparatus (16) seed crystal (12) drop to go up in the middle part of the thermal insulation layer about after; Body of heater (2) is vacuumized, reach predetermined vacuum level 6 * 10
-3Begin to warm to 2100 ℃ behind the Pa, treat raw material fusing fully after, slowly lower temperature near the aluminum oxide fusing point; Get into the liquation range of stability, observe the stove internal state, when treating that surperficial flow presents the spoke-like to center flow through vision slit (15); The seed crystal (12) that can repeatedly slowly descend in case seed crystal (12) receives too big thermal shocking, carries out seeding according to common process afterwards; Shouldering, isometrical and cooling annealing operation.
Through adjusting thermal insulation layer height and rising or falling speed thereof, can lift means such as rotation, cooling through adjusting water coolant, seed rod and chuck in addition and carry out the thermal field adjusting, the thermal field adjustability is better, and regulation range is bigger, responds more timely.
In the different steps of crystal growth, to the thermal field demand of its different steps, a kind of embodiment can but be not limited to be: melt on the stage thermal insulation layer position minimum so that reduce energy consumption; The difficulty of critical process so that improve thermograde, is reduced in thermal insulation layer position on can improving slightly in inoculation, shouldering stage, helps improving yield rate and quality; Thermal insulation layer invariant position in the isometrical maintenance of Cheng Qian semiosis excessively can guarantee crystal mass; Reduce at isometrical process second half section crystallization power; Increasing motivating force by cooling merely can cause crystalline growth velocity not controlled too soon; Go up thermal insulation layer to certain altitude through promoting with certain speed this moment, can overcome this shortcoming, improves the afterbody crystal mass greatly; Simultaneously since motivating force increase, can the growing large-size crystal; In annealing stage and cooling early stage, last thermal insulation layer is placed on extreme lower position can strengthen the effect of annealing, and cuts down the consumption of energy; Thermal insulation layer is placed on the extreme higher position to accelerate cooling on the cooling later stage, shortens growth cycle.In sum; In a complete crystal growing process,, can satisfy the required different thermal fields of the different growth phases of crystal effectively through different positions and the rising or falling speed of adjusting thermal insulation layer; Can improve crystal mass and yield rate greatly; Simultaneously, effectively improve the stable and repeated of technology, be particularly suitable for the industrialization production of large size sapphire crystal.
To distinct device, with between the different heats of equipment and the thermal field difference that causes of feeding quantity difference; In conjunction with to growth parameter(s), summaries of experience such as phenomenon and the crystal mass situation of coming out of the stove are analyzed in the different steps stove, can confirm to go up the different heights position and the height control mode of thermal insulation layer according to the difference of thermal field difference; Can reduce the thermal field intensity of variation between the individuality; Simplify process program, help safeguarding and the stability that improves thermal field and repeated, be particularly suitable for the large size sapphire crystal industrialization and produce.
Claims (4)
1. kyropoulos crystal growing furnace that thermal field is adjustable; Mainly comprise heat protection screen lifting device (1), body of heater (2), water cooled electrode (3), vacuum pipe (4), heating element (5), crucible (6), crucible support system (9), following thermal insulation layer (10), side thermal insulation layer (11), go up thermal insulation layer (13) and rotation and pulling apparatus (16) etc.; It is characterized in that heat protection screen lifting device (1) links to each other with last thermal insulation layer (13); The inside of heating element (5) thermal insulation layer (10), side thermal insulation layer (11), last thermal insulation layer (13) in crucible (6) outside and under being positioned at; Crucible (6) is positioned on the crucible support system (9); Body of heater (2) is provided with vision slit (15) and is convenient to observe crystal (7), melt (8), seed crystal (12), seed rod (14), seed rod (14) through the rotation and pulling apparatus (16) but oscilaltion and rotation.
2. the kyropoulos crystal growing furnace that a kind of thermal field according to claim 1 is adjustable; It is characterized in that; Last thermal insulation layer (13) connects through the top cover lifting device (1) that is fixed on the body of heater; Its position all can be adjustable continuously in position and speed in the 0-100mm altitude range of crucible upper limb position, makes the residing heat radiation final condition of crucible and material change, thereby realize that thermal field is adjustable.
3. the kyropoulos crystal growing furnace that a kind of thermal field according to claim 1 is adjustable; It is characterized in that; Last thermal insulation layer (13) top layer is to be processed by the thick refractory metal plate of one deck 1-5mm; It down is connected with the tungsten thermal insulation layer that 5-20 layer thickness 0.3-2.0mm does not wait, and bottom is molybdenum sheet or the tungsten sheet of a thickness at 2-20mm, and each layer refractory metal or tungsten sheet all have the finedraw that staggers each other with the minimizing high temperature deformation.
4. the kyropoulos crystal growing furnace that a kind of thermal field according to claim 1 is adjustable; It is characterized in that described going up on the thermal insulation layer (13) has through hole, can observe the situation of crystal (7), melt (8), seed crystal (12), seed rod (14) in the stove through viewing window (15).
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Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102864497A (en) * | 2012-09-26 | 2013-01-09 | 南京晶升能源设备有限公司 | Heat insulating system of sapphire single crystal furnace |
| CN102965726A (en) * | 2012-12-19 | 2013-03-13 | 苏州巍迩光电科技有限公司 | Insulation structure applied to sapphire single crystal growth by adopting kyropoulos method |
| CN103147121A (en) * | 2013-04-03 | 2013-06-12 | 中国科学院上海硅酸盐研究所 | Device for growing crystals by using lifting and Kyropoulos method |
| CN103397383A (en) * | 2013-08-14 | 2013-11-20 | 上海森松压力容器有限公司 | Energy-saving sapphire crystal furnace and usage thereof |
| CN103409794A (en) * | 2013-08-16 | 2013-11-27 | 哈尔滨工业大学 | Sapphire single-crystal resistor growth furnace |
| CN103451724A (en) * | 2013-08-28 | 2013-12-18 | 苏州巍迩光电科技有限公司 | Thermal insulation structure with adjustable cold core for growth of sapphire single crystals by virtue of kyropoulos method |
| CN103806101A (en) * | 2012-11-15 | 2014-05-21 | 上海中电振华晶体技术有限公司 | Growth method and equipment of square sapphire crystal |
| CN104451862A (en) * | 2015-01-16 | 2015-03-25 | 苏州恒嘉晶体材料有限公司 | Sapphire single crystal furnace and sapphire seeding method |
| CN104630499A (en) * | 2015-02-28 | 2015-05-20 | 石家庄爱迪尔电气有限公司 | Electromagnetic cyclone ultrapure-aluminum purifying plant |
| CN104651934A (en) * | 2014-10-17 | 2015-05-27 | 洛阳市西格马炉业有限公司 | Energy-saving sapphire crystal growth furnace |
| CN105019024A (en) * | 2015-07-09 | 2015-11-04 | 山东大学 | Method for growing near-stoichiometric lithium niobate crystals by utilizing temperature gradient adjustable temperature field device |
| CN105177711A (en) * | 2015-10-16 | 2015-12-23 | 吉爱华 | Sapphire crystal growing furnace heat field, crystal growing furnace with heat field and crystal growing process of crystal growing furnace |
| JP2016538226A (en) * | 2013-12-03 | 2016-12-08 | エルジー・シルトロン・インコーポレーテッド | Single crystal growth equipment |
| CN106854773A (en) * | 2016-12-29 | 2017-06-16 | 伯恩露笑蓝宝石有限公司 | A kind of crystal growing crucible, device and its growing method |
| CN111906917A (en) * | 2020-07-08 | 2020-11-10 | 大同新成新材料股份有限公司 | Blank processing equipment for graphite thermal field and processing method thereof |
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| CN117305987A (en) * | 2023-11-29 | 2023-12-29 | 北京青禾晶元半导体科技有限责任公司 | Method for eliminating bubble wrapping in liquid phase method silicon carbide crystal growth process |
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2011
- 2011-03-15 CN CN2011100610615A patent/CN102677168A/en active Pending
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| CN102864497A (en) * | 2012-09-26 | 2013-01-09 | 南京晶升能源设备有限公司 | Heat insulating system of sapphire single crystal furnace |
| CN103806101A (en) * | 2012-11-15 | 2014-05-21 | 上海中电振华晶体技术有限公司 | Growth method and equipment of square sapphire crystal |
| CN102965726A (en) * | 2012-12-19 | 2013-03-13 | 苏州巍迩光电科技有限公司 | Insulation structure applied to sapphire single crystal growth by adopting kyropoulos method |
| CN103147121A (en) * | 2013-04-03 | 2013-06-12 | 中国科学院上海硅酸盐研究所 | Device for growing crystals by using lifting and Kyropoulos method |
| CN103147121B (en) * | 2013-04-03 | 2015-10-21 | 中国科学院上海硅酸盐研究所 | The device of lift kyropoulos growing crystal |
| CN103397383B (en) * | 2013-08-14 | 2016-03-09 | 上海森松压力容器有限公司 | A kind of energy-conservation sapphire crystal furnace and using method thereof |
| CN103397383A (en) * | 2013-08-14 | 2013-11-20 | 上海森松压力容器有限公司 | Energy-saving sapphire crystal furnace and usage thereof |
| CN103409794A (en) * | 2013-08-16 | 2013-11-27 | 哈尔滨工业大学 | Sapphire single-crystal resistor growth furnace |
| CN103451724A (en) * | 2013-08-28 | 2013-12-18 | 苏州巍迩光电科技有限公司 | Thermal insulation structure with adjustable cold core for growth of sapphire single crystals by virtue of kyropoulos method |
| US10066315B2 (en) | 2013-12-03 | 2018-09-04 | Sk Siltron Co., Ltd. | Single crystal growing apparatus |
| EP3078768A4 (en) * | 2013-12-03 | 2017-07-12 | LG Siltron Incorporated | Single crystal growing apparatus |
| JP2016538226A (en) * | 2013-12-03 | 2016-12-08 | エルジー・シルトロン・インコーポレーテッド | Single crystal growth equipment |
| CN104651934B (en) * | 2014-10-17 | 2017-12-01 | 洛阳西格马炉业股份有限公司 | A kind of energy-saving sapphire crystal growing furnace |
| CN104651934A (en) * | 2014-10-17 | 2015-05-27 | 洛阳市西格马炉业有限公司 | Energy-saving sapphire crystal growth furnace |
| CN104451862B (en) * | 2015-01-16 | 2017-09-01 | 苏州恒嘉晶体材料有限公司 | A kind of sapphire single-crystal furnace and sapphire seeding methods |
| CN104451862A (en) * | 2015-01-16 | 2015-03-25 | 苏州恒嘉晶体材料有限公司 | Sapphire single crystal furnace and sapphire seeding method |
| CN104630499A (en) * | 2015-02-28 | 2015-05-20 | 石家庄爱迪尔电气有限公司 | Electromagnetic cyclone ultrapure-aluminum purifying plant |
| CN105019024B (en) * | 2015-07-09 | 2018-02-06 | 山东大学 | A kind of method that lithium niobate crysal near stoichiometric ratio is grown using the adjustable thermal field device of thermograde |
| CN105019024A (en) * | 2015-07-09 | 2015-11-04 | 山东大学 | Method for growing near-stoichiometric lithium niobate crystals by utilizing temperature gradient adjustable temperature field device |
| CN105177711A (en) * | 2015-10-16 | 2015-12-23 | 吉爱华 | Sapphire crystal growing furnace heat field, crystal growing furnace with heat field and crystal growing process of crystal growing furnace |
| CN106854773A (en) * | 2016-12-29 | 2017-06-16 | 伯恩露笑蓝宝石有限公司 | A kind of crystal growing crucible, device and its growing method |
| CN106854773B (en) * | 2016-12-29 | 2019-05-03 | 伯恩露笑蓝宝石有限公司 | A kind of crystal growing crucible, device and its growing method |
| CN111906917A (en) * | 2020-07-08 | 2020-11-10 | 大同新成新材料股份有限公司 | Blank processing equipment for graphite thermal field and processing method thereof |
| CN112795980A (en) * | 2020-12-21 | 2021-05-14 | 中山大学 | Temperature field regulation and control device for artificial crystal growth and temperature field dynamic regulation and control method |
| CN117305987A (en) * | 2023-11-29 | 2023-12-29 | 北京青禾晶元半导体科技有限责任公司 | Method for eliminating bubble wrapping in liquid phase method silicon carbide crystal growth process |
| CN117305987B (en) * | 2023-11-29 | 2024-03-12 | 北京青禾晶元半导体科技有限责任公司 | Method for eliminating bubble wrapping in liquid phase method silicon carbide crystal growth process |
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Application publication date: 20120919 |