CN101333114A - Method for making high-thermal-conductivity aluminium nitride ceramics substrate - Google Patents
Method for making high-thermal-conductivity aluminium nitride ceramics substrate Download PDFInfo
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- CN101333114A CN101333114A CNA2008101426970A CN200810142697A CN101333114A CN 101333114 A CN101333114 A CN 101333114A CN A2008101426970 A CNA2008101426970 A CN A2008101426970A CN 200810142697 A CN200810142697 A CN 200810142697A CN 101333114 A CN101333114 A CN 101333114A
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Abstract
The invention relates to the microelectronic packaging material field, in particular to a manufacturing method for a high-thermal-conductive aluminum nitride ceramic substrate. The method selects high-purity aluminum nitride powder as raw material; the average particle size of the high-purity aluminum nitride powder is 1-1.5 micron; 2-4.4 wt% of yttria is added to serve as sintering additive; then adhesive, plasticizer and organic flux are added to form slurry after ball-mill dispersion, followed by tape casting and press forming; the blank pieces are coated with aluminum nitride powders, with every 10-15 blank pieces being piled up as one layer; the laminated aluminum nitride blank pieces are put into a nitride boron crucible, and then mixed powders of aluminum nitride and boron nitride are dispersed into the crucible to cast gel below 500 DEG C; the gel is heated to 1850 DEG C and sintered, and then cooled with the furnace so as to get the aluminum nitride ceramic substrate after final powder polishing. The manufacturing method has the advantages of greatly enhancing the production efficiency, improving product quality; improving the aluminum nitride ceramic substrate sintering atmosphere to obtain sintering products with good consistency and increase production yield, as well as reducing the boron nitride crucible usage to increase the loaded burning amount and save energy costs.
Description
Technical field
The technology of the present invention relates to the microelectronic packaging material field, relates in particular to a kind of making method of high-thermal-conductivity aluminium nitride ceramics substrate, and it is mainly used in ceramic packing.
Background technology
Aluminium nitride ceramics has good heat conductivility, and nontoxic, insulation, and becomes the ideal electronic package material, and application prospect is very wide.At present, a lot of producers and research unit are arranged all at the aluminium nitride ceramic substrate of developing or developed high thermal conductivity both at home and abroad, companies such as the Tokuyama that wherein recognizes, NTK, TOSHIBA develop＞the 180w/m.k aluminium nitride ceramic substrate, and put on market; Domesticly also have many incorporated businesses to claim to make＞aluminium nitride ceramic substrate of 200w/m.k, but mostly rest on laboratory stage, its product mostly＜170w/m.k, be difficult to the aluminium nitride chip that stably provides high-quality.
The making method of present a kind of high-thermal-conductivity aluminium nitride ceramics substrate is as follows: selecting median size earlier for use is high-purity aluminum nitride powder about 1 μ m, adopt the dry pressuring forming process moulding, at 500 ℃ of binder removals of air, put into boron nitride crucible then and feed nitrogen, 1800 ℃ are incubated 1-3 hour, furnace cooling, prepared alumimium nitride ceramic sheet thermal conductivity can reach about 160w/m.k.
Above-mentioned aluminium nitride ceramics manufacturing process is owing to adopt dry pressuring forming process, so can produce the substrate of thickness＞1mm, but its production efficiency is lower, in addition owing to adopt the boron nitride crucible dress to burn, therefore the sintering that helps aluminium nitride chip, but its dress burning amount is relatively low, and boron nitride crucible easy consumption at high temperature, increased production cost, and the aluminium nitride ceramic substrate thermal conductivity of making is also lower.
Also have a kind of making method of high-thermal-conductivity aluminium nitride ceramics substrate as follows: as China Patent No. is 98125129.3, it is described that name is called ' a kind of method of making high thermal conductivity integrated circuit aluminum nitride ceramic substrate with casting method ': 1) at first in aluminum nitride powder in proportion as go into sintering aid, stir; 2) in powder, add softening agent, suspension agent, binding agent and solvent after, through vibration, make slurry; 3) above-mentioned slurry is made ceramic base band by the curtain coating forming mill, the oven dry back becomes solid base band then, and the base band is tailored into the base sheet; 4) sintering; 5) promptly make aluminium nitride ceramic substrate after the cooling.
The aluminium nitride ceramic substrate thermal conductivity is low, except relevant with the quality of aluminium nitride powder, the selection of sintering agent etc., with sintering technology much relations is arranged also.The main performance index thermal conductivity of aluminium nitride ceramic substrate is big with every stove fluctuation, and the substrate planeness is wayward.In addition, aluminium nitride ceramic substrate dress burning amount is low, and output is lower, expends the cost height.
Based on the weak point of above-mentioned existing aluminium nitride ceramics manufacturing process, the inventor has designed the present invention's " a kind of making method of high-thermal-conductivity aluminium nitride ceramics substrate ".
Summary of the invention
The present invention is directed to above-mentioned the deficiencies in the prior art technical problem to be solved is: a kind of production efficiency height is provided, expends the high manufacturing process of aluminium nitride ceramic substrate thermal conductivity that cost is low and produce.
The technical solution adopted for the present invention to solve the technical problems is:
A kind of making method of high-thermal-conductivity aluminium nitride ceramics substrate, it selects high-purity aluminum nitride powder for use is raw material, add sintering aid at aluminum nitride powder, add caking agent again, softening agent and organic solvent, after Ball milling, form uniform and stable slurry, carrying out flow casting molding again is thin slice, thin slice with flow casting molding strikes out the base sheet earlier, to apply aluminum nitride powder on the onesize base sheet again, 10-15 sheet lamination, the aluminium nitride base sheet of lamination is put into boron nitride crucible, spill aluminium nitride and boron nitride powder mix covering mixing on every side at aluminium nitride base sheet then and bury burning, carry out binder removal earlier, heat up then and carry out sintering circuit, furnace cooling carries out cooled alumimium nitride ceramic sheet the gumming polishing at last afterwards, obtains the high-heat conductivity aluminium nitride ceramics substrate.
Described high purity nitrogenize aluminium powder median size is 1～1.5 μ m, sintering aid is the yttrium oxide of 2～4.4wt%, organic solvent is a toluene, Virahol or alcohol, after Ball milling, form uniform and stable slurry, carrying out flow casting molding again is the thick thin slice of thickness 0.6-1mm, thin slice with flow casting molding strikes out the base sheet earlier, to apply aluminum nitride powder on the onesize base sheet again, 10-15 sheet lamination, the aluminium nitride base sheet of lamination is put into boron nitride crucible, spill the covering of aluminium nitride and boron nitride powder mix on every side at aluminium nitride base sheet then and bury burning, earlier under 500 ℃, carry out binder removal, be warming up to 1850 ℃ then and carry out sintering circuit, furnace cooling afterwards, at last cooled alumimium nitride ceramic sheet is carried out the gumming polishing, promptly obtain the aluminium nitride ceramic substrate of high heat conductance.
Described caking agent is a polyvinyl butyral acetal, and softening agent is a dibutyl phthalate.
Described lamination aluminium nitride base sheet is put into crucible, and with the powder mix covering of aluminum nitride powder and each 50wt% of boron nitride, 500 ℃ of binder removals in the binder removal stove are put into Vacuum graphite oven then earlier, with 100 ℃ of/hour intensifications, feed N when reaching 800 ℃
2, be warming up to 1850 ℃ after, be incubated 1 hour, then furnace cooling.It is the high purity nitrogenize aluminium powder of 1～1.5 μ m that the present invention selects median size for use, the yttrium oxide that adds 2～4.4wt% is as sintering aid, add an amount of caking agent polyvinyl butyral acetal, plasticizer phthalic acid dibutylester etc. and organic solvent toluene, Virahol, alcohol etc. again, form uniform and stable slurry after Ball milling, carrying out flow casting molding again is the thick thin slice of thickness 0.6-1mm.Impact briquetting, to apply aluminum nitride powder on the onesize base sheet, 10-15 sheet lamination, the aluminium nitride base sheet of lamination is put into boron nitride crucible, spill aluminium nitride and boron nitride powder mix around the base sheet and cover, in 500 ℃ of following binder removals, be warming up to 1850 ℃ of sintering then, furnace cooling with cooled alumimium nitride ceramic sheet gumming polishing, promptly obtains the aluminium nitride ceramic substrate of high heat conductance.
Adopt the casting molding processes moulding, can enhance productivity greatly, select highly purified aluminium nitride powder for use, ratio, the kind of controlling its granularity and sintering agent improve product quality.The present invention adopts the mode of 10～15 laminations, mixes the method for burying burning with aluminum nitride powder and boron nitride powder, can reduce the consumption of boron nitride crucible, increases the dress burning amount of aluminium nitride base sheet in every stove, has saved energy cost.The burning method is buried in employing, makes the sintering atmosphere uniformity of base sheet, can obtain the sinter of high conformity.
The making method beneficial effect of a kind of high-thermal-conductivity aluminium nitride ceramics substrate of the present invention is:
1), owing to adopt the casting molding processes moulding, therefore can enhance productivity greatly, select highly purified aluminium nitride powder in addition for use, ratio, the kind of controlling its granularity and sintering agent improve product quality;
2), the present invention adopts the mode of 10～15 laminations, mix the method for burying burning with aluminum nitride powder and boron nitride powder, improve aluminium nitride ceramic substrate agglomerating atmosphere, make the sintering atmosphere uniformity of base sheet, improve sintering technology, can obtain the sinter of high conformity, and increase the output of ceramic substrate;
3), the present invention adopts aluminium nitride and boron nitride powder to bury burning, can reduce the consumption of boron nitride crucible, increases the dress burning amount of aluminium nitride base sheet in every stove, saved energy cost.
Embodiment
The present invention implements like this:
At first selecting particle diameter for use is the high purity nitrogenize aluminium powder of 1.2 μ m, and oxygen level is 1.2%, makes 1 kilogram aluminium nitride ceramic substrate, and each becomes component to be:
Aluminium nitride 0.958kg
Yttrium nitride 0.042kg
Polyvinyl butyral (PVB) 0.22kg
DBP 0.03kg
Toluene 0.4kg
Virahol 0.02.kg
Manufacture craft is as follows: at first 0.958 kilogram aluminum nitride powder and 0.042 kilogram yttrium oxide powder are put into ball grinder, add 0.4 kilogram of toluene again, 0.02 kilogram Virahol, 0.02 kilogram polyvinyl butyral (PVB), ball milling 10 hours is made uniform slurry, and then adds 0.03 kilogram of DBP, 0.2 kilogram polyvinyl butyral (PVB), ball milling 10 hours.
The slurry that makes is taken out, deaeration, old, viscosity 6000～8000CPS makes the thick film band of 1mm by casting machine, after section, impact briquetting, applies aluminum nitride powder, 15 one laminations.
The aluminium nitride base sheet of lamination is put into crucible, and with the powder mix covering of aluminum nitride powder and each 50wt% of boron nitride, 500 ℃ of binder removals in the binder removal stove are put into Vacuum graphite oven then earlier, and 100 ℃ of/hour intensifications feed N when reaching 800 ℃
2, be warming up to 1850 ℃ after, be incubated 1 hour, then furnace cooling.
Cooled alumimium nitride ceramic sheet is removed every sticking powder, polished, promptly obtain the aluminium nitride ceramic substrate of high heat conductance.
The above, it only is the making method preferred embodiment of a kind of high-thermal-conductivity aluminium nitride ceramics substrate of the present invention, be not that technical scope of the present invention is imposed any restrictions, every foundation technical spirit of the present invention all still belongs in the scope of the technology of the present invention content any trickle modification, equivalent variations and modification that top embodiment did.
Claims (5)
1, a kind of making method of high-thermal-conductivity aluminium nitride ceramics substrate, it selects high-purity aluminum nitride powder for use is raw material, adds sintering aid in aluminum nitride powder, adds caking agent, softening agent and organic solvent again, form uniform and stable slurry after Ball milling, carrying out flow casting molding again is thin slice; The invention is characterized in: the thin slice with flow casting molding strikes out the base sheet earlier, to apply aluminum nitride powder on the onesize base sheet again, 10-15 sheet lamination is put into boron nitride crucible with the aluminium nitride base sheet of lamination, spills aluminium nitride and boron nitride powder mix covering sintering then around aluminium nitride base sheet; Carry out binder removal earlier, heat up then and carry out sintering circuit, furnace cooling carries out cooled alumimium nitride ceramic sheet the gumming polishing at last afterwards, obtains the high-heat conductivity aluminium nitride ceramics substrate.
2, the making method of a kind of high-thermal-conductivity aluminium nitride ceramics substrate according to claim 1, it is characterized in that described high purity nitrogenize aluminium powder median size is 1～1.5 μ m, sintering aid is the yttrium oxide of 2～4.4wt%, organic flux is a toluene, Virahol or alcohol, after Ball milling, form uniform and stable slurry, carrying out flow casting molding again is the thick thin slice of thickness 0.6-1mm, thin slice with flow casting molding strikes out the base sheet earlier, to apply aluminum nitride powder on the onesize base sheet again, 10-15 sheet lamination, the aluminium nitride base sheet of lamination is put into boron nitride crucible, spill the covering of aluminium nitride and boron nitride powder mix on every side at aluminium nitride base sheet then and bury burning, under 500 ℃, carry out earlier binder removal, be warming up to 1850 ℃ then and carry out sintering circuit, furnace cooling carries out the gumming glossing with cooled alumimium nitride ceramic sheet at last afterwards, promptly obtains the aluminium nitride ceramic substrate of high heat conductance.
3, the making method of a kind of high-thermal-conductivity aluminium nitride ceramics substrate according to claim 1 is characterized in that described caking agent is a polyvinyl butyral acetal.
4, the making method of a kind of high-thermal-conductivity aluminium nitride ceramics substrate according to claim 1 is characterized in that described softening agent is a dibutyl phthalate.
The making method of 5 a kind of high-thermal-conductivity aluminium nitride ceramics substrates according to claim 1 and 2, it is characterized in that described lamination aluminium nitride base sheet puts into crucible, powder mix with aluminum nitride powder and each 50wt% of boron nitride covers, elder generation's 500 ℃ of binder removals in the binder removal stove, put into Vacuum graphite oven then, with 100 ℃ of/hour intensifications, when reaching 800 ℃, feed N
2, be warming up to 1850 ℃ of sintering, be incubated 1 hour, then furnace cooling.
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| CN102433088A (en) * | 2011-08-17 | 2012-05-02 | 广东风华高新科技股份有限公司 | Adhesive for chip multilayer ceramic capacitor and preparation method of adhesive |
| CN101565302B (en) * | 2009-04-09 | 2012-12-26 | 潮州三环（集团）股份有限公司 | Ceramic packaging material for LED and production method thereof |
| CN103121238A (en) * | 2013-02-25 | 2013-05-29 | 潮州三环（集团）股份有限公司 | Tape casting aluminum nitride green body manufacturing method |
| CN103121848A (en) * | 2013-02-25 | 2013-05-29 | 潮州三环（集团）股份有限公司 | Aluminum nitride ceramic substrate sintering technology |
| CN103295914A (en) * | 2012-02-29 | 2013-09-11 | 深圳光启创新技术有限公司 | Metamaterial based on ceramic substrates and preparation method thereof |
| CN103360070A (en) * | 2012-03-31 | 2013-10-23 | 深圳光启创新技术有限公司 | Ceramic substrate based metamaterial and preparation method |
| CN104649677A (en) * | 2013-11-18 | 2015-05-27 | 北京大学 | A method of preparing an aluminium nitride ceramic substrate by gel casting |
| CN106431419A (en) * | 2016-09-22 | 2017-02-22 | 合肥圣达电子科技实业有限公司 | Preparation method of aluminum nitride ceramic substrate with high thermal conductivity for high power microelectronic devices |
| CN108439993A (en) * | 2018-05-31 | 2018-08-24 | 华南理工大学 | It is a kind of with AlN/C be bury burn powder high heat conductance AlN ceramic and preparation method thereof |
| CN108640689A (en) * | 2018-05-22 | 2018-10-12 | 南京萨特科技发展有限公司 | A kind of ceramic tube preparation method of high breaking fuse |
| CN110770193A (en) * | 2017-06-30 | 2020-02-07 | 株式会社美科 | Aluminum nitride sintered body and member for semiconductor manufacturing apparatus including the same |
| CN111702670A (en) * | 2020-06-30 | 2020-09-25 | 郑州高新磨料磨具有限公司 | Ultrathin ceramic diamond grinding wheel and preparation method thereof |
| CN113213944A (en) * | 2021-05-24 | 2021-08-06 | 南京工程学院 | BN nanosheet toughened high-thermal-conductivity AlN ceramic substrate and preparation method thereof |
| CN114105651A (en) * | 2021-08-31 | 2022-03-01 | 森霸传感科技股份有限公司 | Manufacturing method of pyroelectric ultrathin ceramic chip and application of pyroelectric ultrathin ceramic chip to sensor |
| CN115536399A (en) * | 2022-11-02 | 2022-12-30 | 无锡海古德新技术有限公司 | Full aluminum nitride ceramic heating structure device and preparation method thereof |
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- 2008-07-31 CN CNA2008101426970A patent/CN101333114A/en active Pending
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| CN101565302B (en) * | 2009-04-09 | 2012-12-26 | 潮州三环（集团）股份有限公司 | Ceramic packaging material for LED and production method thereof |
| CN102433088A (en) * | 2011-08-17 | 2012-05-02 | 广东风华高新科技股份有限公司 | Adhesive for chip multilayer ceramic capacitor and preparation method of adhesive |
| CN103295914B (en) * | 2012-02-29 | 2018-01-16 | 深圳光启高等理工研究院 | A kind of Meta Materials based on ceramic substrate and preparation method thereof |
| CN103295914A (en) * | 2012-02-29 | 2013-09-11 | 深圳光启创新技术有限公司 | Metamaterial based on ceramic substrates and preparation method thereof |
| CN103360070A (en) * | 2012-03-31 | 2013-10-23 | 深圳光启创新技术有限公司 | Ceramic substrate based metamaterial and preparation method |
| CN103360070B (en) * | 2012-03-31 | 2015-11-18 | 深圳光启创新技术有限公司 | A kind of based on ceramic substrate metamaterial and preparation method |
| CN103121238A (en) * | 2013-02-25 | 2013-05-29 | 潮州三环（集团）股份有限公司 | Tape casting aluminum nitride green body manufacturing method |
| CN103121848A (en) * | 2013-02-25 | 2013-05-29 | 潮州三环（集团）股份有限公司 | Aluminum nitride ceramic substrate sintering technology |
| CN103121238B (en) * | 2013-02-25 | 2015-04-29 | 潮州三环（集团）股份有限公司 | Tape casting aluminum nitride green body manufacturing method |
| CN103121848B (en) * | 2013-02-25 | 2015-08-19 | 潮州三环（集团）股份有限公司 | A kind of aluminum nitride ceramic substrate sintering process |
| CN104649677A (en) * | 2013-11-18 | 2015-05-27 | 北京大学 | A method of preparing an aluminium nitride ceramic substrate by gel casting |
| CN106431419A (en) * | 2016-09-22 | 2017-02-22 | 合肥圣达电子科技实业有限公司 | Preparation method of aluminum nitride ceramic substrate with high thermal conductivity for high power microelectronic devices |
| CN110770193A (en) * | 2017-06-30 | 2020-02-07 | 株式会社美科 | Aluminum nitride sintered body and member for semiconductor manufacturing apparatus including the same |
| US11508586B2 (en) | 2017-06-30 | 2022-11-22 | Mico Ceramics Ltd. | Aluminum nitride sintered body and member for semiconductor manufacuting apparatus comprising same |
| CN108640689A (en) * | 2018-05-22 | 2018-10-12 | 南京萨特科技发展有限公司 | A kind of ceramic tube preparation method of high breaking fuse |
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