CN106431419A - Preparation method of aluminum nitride ceramic substrate with high thermal conductivity for high power microelectronic devices - Google Patents
Preparation method of aluminum nitride ceramic substrate with high thermal conductivity for high power microelectronic devices Download PDFInfo
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- CN106431419A CN106431419A CN201610839445.8A CN201610839445A CN106431419A CN 106431419 A CN106431419 A CN 106431419A CN 201610839445 A CN201610839445 A CN 201610839445A CN 106431419 A CN106431419 A CN 106431419A
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
- C04B35/58—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides
- C04B35/581—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on aluminium nitride
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Abstract
The invention provides a preparation method of an aluminum nitride ceramic substrate with high thermal conductivity for high power microelectronic devices. The method comprises the steps of collecting ingredients, preparing green bodies, conducting derosination and conducting sintering. The step of collecting ingredients comprises the steps of weighing high purity aluminum nitride powder, yttrium oxide sintering assistant, organic solvent and additives, and stirring the ingredients uniformly. The step of preparing green body applies the combination of methods of both tape casting and isostatic pressing process. The derosination step is to use the mixed atmosphere of hydrogen and nitrogen and apply the derosination temperature of 400-1000 DEG C. The sintering step applies the temperature of 1750-1950 DEG C and a sintering duration of 3-40 hours. The method uses the single yttrium oxide sintering assistant and scale tape casting. The derosination process uses the hydrogen and nitrogen mixed atmosphere which can effectively control the carbon and oxygen element content in green bodies after the derosination. The sintering is under normal pressure. The acquired aluminum nitride ceramic has a heat conductivity of 180W/m.K-268 W/m.K. The method has the advantages of simple processing, good product performance, low production cost and convenience for industrialization.
Description
Technical field
The present invention relates to High power microelectronic device arts are and in particular to a kind of high heat conduction aluminum nitride ceramic substrate
Preparation method.
Background technology
The technology such as large scale integrated circuit, multi-chip module and MEMS develop rapidly so that various electronic equipment will
Powerful function is integrated in less assembly.Advanced electronic building brick high density and powerful feature will lead to its caloric value
It is increased sharply, power dissipation increases sharply, therefore heat-sinking capability has become the most important factor of impact electronic reliability.
Aluminium nitride is a kind of new non-oxide ceramic material, the thermal conductivity of Yin Qigao（Theoretical value 320W/m.K）, low
Dielectric constant, nontoxic, superior insulating properties, the thermal coefficient of expansion being matched with silicon and other excellent physical and chemical performance are subject to
Arrive the extensive concern of domestic and international academia and manufacturer, be described as the preferable substrate material of High power microelectronic device of new generation
Material.
According to the patent delivered, publication number：CN 104973865 A, using rare earth metal fluoride EuF3, LaF3,
SmF3 or its mixture are sintering aid, repressed shaping or injection moulding, nitrogen degreasing, prepare 200W/m.K～
The ceramic substrate of 230W/m.K；Publication number：CN 104072158 A, using Li2O-B2O3-SiO2 and MnCO3-CuO mixed powder
The pottery that thermal conductivity is 220 W/m.K, as sintering aid, flow casting molding, degreasing in air atmosphere, microwave sintering, is prepared in end
Porcelain substrate；The patent No.：CN 103204682 B, dry-pressing formed blank carries out degreasing by vacuum degreasing stove, by the base of degreasing
Material is fired into just finished product by vibrating hot-pressed sintering furnace, and by first finished product thermal insulation pressurize 0.5～8 h, along with the furnace cooling obtains 200
～260W/m.k ceramic substrate.The shortcoming of above-mentioned preparation method is as follows：Complex process, be not suitable for industrialization, thermal conductivity scope no
Method covers 180～268W/m.k.
Conventional nitridation aluminium Production of Ceramics process, all using degreasing under air or nitrogen atmosphere, degreasing in atmosphere, it will
Introduce excessive oxygen element, be only used yittrium oxide as sintering aid under conditions of, normal pressure-sintered thermal conductivity can only achieve
170W/m.k；Degreasing will not introduce the oxygen element of in the air under a nitrogen, and thermal conductivity will improve；But ball milling mistake
Oxygen element in oxygen element in oxygen element that journey is introduced into, aluminium nitride powder and yittrium oxide, limits the raising further of thermal conductivity,
Therefore effectively removing oxygen element is the key improving thermal conductivity.
Content of the invention
The present invention provides a kind of preparation method of high heat conduction aluminum nitride ceramic substrate, gained heat dispersion substrate of ceramics not only thermal conductivity
Rate is up to 268W/m.K, and can be adjusted by degreasing atmosphere and sintering process and obtain thermal conductivity in 180W/m.K～268W/
The ceramic substrate of change in the range of m.K, adopts single sintering aid, the tape casting, the ceramic substrate scale metaplasia such as normal pressure-sintered simultaneously
Production. art, production efficiency is high, low cost.
For solving above-mentioned technical problem, the present invention adopts the following technical scheme that：
A kind of High power microelectronic device preparation method of high heat conduction aluminum nitride ceramic substrate, comprises the steps：
1）Dispensing：Weigh high-purity aluminium nitride powder, yttrium oxide sintering aid, organic solvent and additive, and mix；
2）Prepared by green compact：Green compact are obtained using the method that flow casting molding is combined with isostatic pressing process；
3）Degreasing：Degreasing, 400～1000 DEG C of skimming temp, degreasing time 15～50h are carried out using hydrogen/nitrogen mixed atmosphere；
4）Sintering：Green compact after degreasing are carried out normal pressure-sintered, 1750～1950 DEG C of sintering temperature, sintering time 3～40h.
The consumption of described yttrium oxide sintering aid is the 2%～6% of aluminum nitride powder body weight.
The detailed process of described green compact preparation is：Slurry is obtained after casting machine thickness between 0.1～0.7mm
Base substrate, then through pressure 10～24MPa on isostatic pressing machine, obtains ceramic green.
Degreasing is carried out using hydrogen/nitrogen mixed atmosphere, hydrogen/nitrogen flow is than for 1/100～1/1.
From above technical scheme, the present invention carries out degreasing using the atmosphere of hydrogen/nitrogen, and carbon, oxygen can be controlled to contain
Amount；The introducing of oxygen element can not only be controlled, enable to trace carbon simultaneously and remain in inside ceramic body, in sintering process
Carbon and oxygen element combine so that oxygen element removes pottery, thus improving thermal conductivity；Adopt simple effective method simultaneously,
Single sintering aid, scale forming method, are 180W/m.K～268W/m.K's through normal pressure-sintered thermal conductivity of can preparing
High heat conduction aluminium nitride substrate.
Specific embodiment
Thermal conductivity is the key index of aluminium nitride ceramics, and thermal conductivity is closely related with the oxygen content in pottery, contains with oxygen
The raising of amount, thermal conductivity is gradually reduced, and the present invention carries out degreasing by the atmosphere of hydrogen/nitrogen, controls carbon, oxygen content, degreasing
Carbon element content is 0.1%～0.3% afterwards, and oxygen element content is 2%～5%, and the thermal conductivity of obtained high heat conduction aluminium nitride substrate exists
Adjustable in the range of 180W/m.K～268W/m.K.
Below in conjunction with specific embodiment, the present invention is described in detail, in the skill describing various embodiments of the present invention in detail
Before art scheme, involved noun and term are explained, in this manual, title is identical or label identical portion
Part represents similar or identical structure, and is only limitted to the purpose illustrated.
Embodiment 1
Step 1, dispensing：Using business aluminium nitride powder 3000g, yittrium oxide sintering aid 120g, acrylic resin as dispersant
30g, PVB are as binding agent 560g, butanone/isopropanol（1:1）As solvent 4380g；PEG and DMP（1:1）As plasticizer
200g, mixing and ball milling 24h obtains casting slurry.
Step 2, green compact preparation：Slurry through flow casting molding, base substrate thickness 0.4mm, then through isostatic pressed, pressure 15MPa, temperature
70 DEG C of degree laminates shaping, obtains green density 2.0g/cm3.
Step 3, degreasing：Using hydrogen/nitrogen mixed atmosphere, hydrogen/nitrogen flow is than for 1/50；Skimming temp 500
DEG C, degreasing time 30h；After degreasing, carbon element content is 0.11%, and oxygen element content is 3.2%.
Step 4, sintering：Green compact after degreasing are put into and carries out normal pressure-sintered in graphite high temp. furnace, nitrogen is as shielding gas
Atmosphere, 1800 DEG C of sintering temperature, sintering time 3h.
It is 188W/m.K by the aluminium nitride ceramics thermal conductivity that this technique is obtained.
Embodiment 2
The method of the present embodiment is essentially identical with embodiment 1, and difference is step 3 and step 4：
Step 3, degreasing：Using hydrogen/nitrogen mixed atmosphere, hydrogen/nitrogen flow is than for 1/20；700 DEG C of skimming temp, degreasing
Time 26h；After degreasing, carbon element content is 0.18%, and oxygen element content is 2.9%.
Step 4, sintering：Green compact after degreasing are put into and carries out normal pressure-sintered in graphite high temp. furnace, nitrogen is as shielding gas
Atmosphere, 1850 DEG C of sintering temperature, sintering time 8h.
It is 224W/m.K by the aluminium nitride ceramics thermal conductivity that this technique is obtained.
Embodiment 3
The method of the present embodiment is essentially identical with embodiment 1, and difference is step 3 and step 4：
Step 3, degreasing：Using hydrogen/nitrogen mixed atmosphere, hydrogen/nitrogen flow is than for 1/5；900 DEG C of skimming temp, degreasing
Time 24h；After degreasing, carbon element content is 0.23%, and oxygen element content is 2.7%.
Step 4, sintering：Green compact after degreasing are put into and carries out normal pressure-sintered in graphite high temp. furnace, nitrogen is as shielding gas
Atmosphere, 1900 DEG C of sintering temperature, sintering time 24h.
It is 268W/m.K by the aluminium nitride ceramics thermal conductivity that this technique is obtained.
The above embodiment is only that the preferred embodiment of the present invention is described, the not model to the present invention
Enclose and be defined, on the premise of without departing from design spirit of the present invention, the technical side to the present invention for the those of ordinary skill in the art
Various modifications and improvement that case is made, all should fall in the protection domain of claims of the present invention determination.
Claims (4)
1. a kind of preparation method of High power microelectronic device high heat conduction aluminum nitride ceramic substrate it is characterised in that include as
Lower step：
1）Dispensing：Weigh high-purity aluminium nitride powder, yttrium oxide sintering aid, organic solvent and additive, and mix；
2）Prepared by green compact：Green compact are obtained using the method that flow casting molding is combined with isostatic pressing process；
3）Degreasing：Degreasing, 400～1000 DEG C of skimming temp, degreasing time 15～50h are carried out using hydrogen/nitrogen mixed atmosphere；
4）Sintering：Green compact after degreasing are carried out normal pressure-sintered, 1750～1950 DEG C of sintering temperature, sintering time 3～40h.
2. preparation method according to claim 1 is it is characterised in that the consumption of described yttrium oxide sintering aid is aluminium nitride
The 2%～6% of powder weight.
3. preparation method according to claim 1 is it is characterised in that the detailed process of described green compact preparation is：By slurry
Obtain base substrate between 0.1～0.7mm for the thickness after casting machine, then through pressure 10～24MPa on isostatic pressing machine, obtain
Obtain ceramic green.
4. preparation method according to claim 1 is it is characterised in that carry out degreasing, hydrogen using hydrogen/nitrogen mixed atmosphere
Gas/nitrogen flow is than for 1/100～1/1.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114014669A (en) * | 2021-12-16 | 2022-02-08 | 河北中瓷电子科技股份有限公司 | Preparation method of stretch-resistant aluminum nitride raw ceramic substrate |
| CN114710847A (en) * | 2022-04-09 | 2022-07-05 | 莱鼎电子材料科技有限公司 | Electronic ceramic heater for semiconductor chip sealing and testing and preparation method thereof |
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| CN102030538A (en) * | 2009-09-30 | 2011-04-27 | 比亚迪股份有限公司 | Production method of aluminum nitride ceramic and aluminum nitride ceramic prepared by same |
| CN104844221A (en) * | 2015-04-20 | 2015-08-19 | 福建华清电子材料科技有限公司 | Making method of heavy gauge aluminum nitride ceramic substrate |
| CN105801127A (en) * | 2016-03-03 | 2016-07-27 | 上海大学 | Method for preparing high-thermal-conductivity aluminum nitride ceramic substrate for integrated circuit package |
-
2016
- 2016-09-22 CN CN201610839445.8A patent/CN106431419A/en active Pending
Patent Citations (5)
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| CN102030538A (en) * | 2009-09-30 | 2011-04-27 | 比亚迪股份有限公司 | Production method of aluminum nitride ceramic and aluminum nitride ceramic prepared by same |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114014669A (en) * | 2021-12-16 | 2022-02-08 | 河北中瓷电子科技股份有限公司 | Preparation method of stretch-resistant aluminum nitride raw ceramic substrate |
| CN114710847A (en) * | 2022-04-09 | 2022-07-05 | 莱鼎电子材料科技有限公司 | Electronic ceramic heater for semiconductor chip sealing and testing and preparation method thereof |
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Application publication date: 20170222 |