GB2127709A - Manufacture of aluminium nitride - Google Patents
Manufacture of aluminium nitride Download PDFInfo
- Publication number
- GB2127709A GB2127709A GB08228522A GB8228522A GB2127709A GB 2127709 A GB2127709 A GB 2127709A GB 08228522 A GB08228522 A GB 08228522A GB 8228522 A GB8228522 A GB 8228522A GB 2127709 A GB2127709 A GB 2127709A
- Authority
- GB
- United Kingdom
- Prior art keywords
- aluminium
- reaction
- rod
- levitated
- charge
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 229910017083 AlN Inorganic materials 0.000 title claims abstract description 25
- PIGFYZPCRLYGLF-UHFFFAOYSA-N Aluminum nitride Chemical compound [Al]#N PIGFYZPCRLYGLF-UHFFFAOYSA-N 0.000 title claims abstract description 25
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 239000004411 aluminium Substances 0.000 claims abstract description 43
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 43
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 42
- 238000006243 chemical reaction Methods 0.000 claims abstract description 42
- 238000005339 levitation Methods 0.000 claims abstract description 23
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 16
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims abstract description 11
- 229910001873 dinitrogen Inorganic materials 0.000 claims abstract description 8
- 229910052593 corundum Inorganic materials 0.000 claims abstract description 7
- 230000005674 electromagnetic induction Effects 0.000 claims abstract description 6
- 229910001845 yogo sapphire Inorganic materials 0.000 claims abstract description 6
- BYFGZMCJNACEKR-UHFFFAOYSA-N aluminium(i) oxide Chemical compound [Al]O[Al] BYFGZMCJNACEKR-UHFFFAOYSA-N 0.000 claims abstract 4
- 238000000034 method Methods 0.000 claims description 27
- 229910052751 metal Inorganic materials 0.000 claims description 11
- 239000002184 metal Substances 0.000 claims description 11
- 229910052757 nitrogen Inorganic materials 0.000 claims description 4
- 239000007787 solid Substances 0.000 claims description 4
- 239000011261 inert gas Substances 0.000 claims description 3
- 239000000155 melt Substances 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 2
- -1 1800 to 2300 DEG C Chemical compound 0.000 abstract description 2
- 239000000047 product Substances 0.000 description 7
- 229910001220 stainless steel Inorganic materials 0.000 description 5
- 239000010935 stainless steel Substances 0.000 description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 239000000376 reactant Substances 0.000 description 4
- 239000013078 crystal Substances 0.000 description 3
- 238000007667 floating Methods 0.000 description 3
- 239000010410 layer Substances 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 238000000859 sublimation Methods 0.000 description 2
- 230000008022 sublimation Effects 0.000 description 2
- 238000010897 surface acoustic wave method Methods 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- CYRGZAAAWQRSMF-UHFFFAOYSA-N aluminium selenide Chemical compound [Al+3].[Al+3].[Se-2].[Se-2].[Se-2] CYRGZAAAWQRSMF-UHFFFAOYSA-N 0.000 description 1
- 238000010960 commercial process Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 239000010431 corundum Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000008246 gaseous mixture Substances 0.000 description 1
- 239000010437 gem Substances 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 239000012768 molten material Substances 0.000 description 1
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 description 1
- 150000002899 organoaluminium compounds Chemical class 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 230000003019 stabilising effect Effects 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- JLTRXTDYQLMHGR-UHFFFAOYSA-N trimethylaluminium Chemical compound C[Al](C)C JLTRXTDYQLMHGR-UHFFFAOYSA-N 0.000 description 1
- 238000001429 visible spectrum Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J4/00—Feed or outlet devices; Feed or outlet control devices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J10/00—Chemical processes in general for reacting liquid with gaseous media other than in the presence of solid particles, or apparatus specially adapted therefor
- B01J10/005—Chemical processes in general for reacting liquid with gaseous media other than in the presence of solid particles, or apparatus specially adapted therefor carried out at high temperatures in the presence of a molten material
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
- C01B21/072—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron with aluminium
- C01B21/0722—Preparation by direct nitridation of aluminium
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
High purity aluminium nitride is manufactured by levitating a charge of molten aluminium (112) in a reaction zone (100) by means of electromagnetic induction in a levitation coil (111) in an oxygen-free atmosphere, reacting the levitated molten aluminium with nitrogen gas at a temperature effective to form aluminium nitride, e.g. 1800 to 2300 DEG C, and recovering the resulting aluminium nitride in an oxygen-free atmosphere. The size of the levitated charge can be monitored and the charge replenished under the control of the monitor. The aluminium to be melted can be stripped of its Al2O3 film by heating to cause Al2O3 to react with Al to form Al2O which is volatile and removed by evacuation. <IMAGE>
Description
SPECIFICATION
Manufacture of aluminium nitride
The present invention is concerned primarily with the manufacture of aluminium nitride, although in some of its aspects it has applications extending beyond aluminium nitride manufacture.
Aluminium nitride potentially has particular value in electronic devices depending on the manipulation of surface acoustic waves, because it has a large electro-mechanical coupling and high resistivity as well as a high propagation velocity for surface acoustic waves. It is also valuable as a substitute gem material and is known to have potential as a light-emitting diode material in the near ultra-violet and as a phosphor at the blue end of the visible spectrum. It has exceedingly high thermal conductivity and high strength and would be useful as an industrial refractory in the form of powder or polycrystalline blocks because it is not attacked by molten aluminium. It is a piezoelectric material of high transparency which could be of use in transducers and in the electro-optical field.
It has been proposed to grow aluminium nitride in the form of an epitaxial film on a corundum support by reaction of an aluminium halide with ammonia at about 1 2000C or by reaction of an organo-aluminium compound such as trimethylaluminium with ammonia. However, both processes have disadvantages and the products obtained tend to contain impurities. Neither process has yet been commercialised despite intense interest in the compounds. The production of aluminium nitride by reaction of nitrogen gas with aluminium selenide has also been proposed but requires more detailed study before it can yield a commercially viable process.
It is not possible to grow aluminium nitride crystals from a melt because the compound decomposes at about 25000C before melting, so that crystals can be grown only by direct sublimation, and for this operation it is of crucial importance to use a starting material of high purity.
The present invention seeks, in one of its aspects, to provide a method for the production of aluminium nitride which can form a basis of a commercial process. In particular it seeks to provide a method of producing high-purity aluminium nitride from which crystals can be obtained by direct sublimation.
According to this first aspect of the invention there is provided a process for the manufacture of
high-purity aluminium nitride comprising levitating
a charge of molten aluminium in a reaction zone
by means of electromagnetic induction in a
levitation coil in an oxygen-free atmosphere,
reacting the levitated molten aluminium at a functionaliy effective temperature with nitrogen
gas and recovering the resulting aluminium nitride
in an oxygen-free atmosphere.
The reaction temperature employed must be
sufficiently high that the protective surface layer of
aluminium nitride which is formed initially is disrupted and does not inhibit further reaction.
Generally speaking, temperatures in excess of 1 5000C will therefore be required. On the other hand the temperature should be below the aluminium nitride decomposition temperature, i.e.
generally speaking below about 25000C.
Preferably, temperatures of about 1 800 to 23000 C, e.g. about 20000 C, are used. At temperatures above 20000C the vapour pressure of aluminium nitride is about 0.1 bar and evaporation takes place freely.
The levitation of the molten aluminium is achieved by means of electromagnetic induction in a levitation coil, which is designed to provide a field pattern creating both an upward levitating force and a radially inward, stabilising force.
Various designs of levitation coils have been proposed in the literature, for example in "Levitation Melting - a survey of the State of the
Art" by W. A. Peifer, Journal of Metals, May 1965, pages 487-493, and "Electromagnetic
Levitation and its use in Physico-Chemical Studies at High Temperature" by A. E. Jenkins, B. Harris and L. Baker, Symposium on Metallurgy at High
Pressures and High Temperatures, Met. Soc.
Conf., 22, New York (1964), pages 23-43. These designs may be used for the process of the present invention. The use of electromagnetic levitation prevents contact between the molten aluminium, which is extremely reactive, and metals or refractories which it would otherwise attack at about 20000 C.
In order to provide good control of the rate of reaction between nitrogen gas and the molten aluminium and to control the temperature of the latter it is desirable to employ a mixture of nitrogen gas and an inert gas, preferably helium, and to control the proportion of nitrogen depending on changes in the aluminium temperature and reaction rate.
It is also important, in order to avoid contamination of the product, that collection of the product should be carried out in an oxygenfree atmosphere.
In a second aspect, the present invention seeks to improve the supply of molten material to a levitation coil. Conventional levitation coiis currently in use are limited to a charge of 10 to 20 g, which is insufficient, in the case of molten aluminium, to produce a worthwhile yield of aluminium nitride from a single run without replenishment of the charge. Although it has been proposed to drop pellets onto a levitated charge to replenish the charge, this is not entirely satisfactory.
According to the second aspect of the present invention apparatus for use in carrying out a chemical reaction in which a levitated mass of non-gaseous material is reacted at elevated temperature with a gas to form a gaseous product, comprises a reaction zone having an inlet for the gaseous reactant and an outlet for the gaseous product and is characterised in that means are provided for the constant replenishment of the levitated mass, said replenishment means comprising an automatic sensor for sensing the size of the levitated mass and drive means
controlled by the sensor for protruding an additional quantity of the non-gaseous reactant into the levitation field to maintain a constant size of the levitated mass.
Conveniently the sensor is a television camera or other device producing an image of the levitated mass and controlling the drive means by suitable electronic processing. Especially where the levitated mass of non-gaseous reactant is a molten solid, the drive means may be linked to a solid rod of the non-gaseous reactant so as to cause its tip to protrude into the levitation field, where the tip is heated and melts and thus replenishes the levitated mass, in response to the progess of the reaction.
This apparatus is particularly suited to use in the reaction of molten metals such as aluminium and others. However when a metal rod, particularly an aluminium rod, is used, difficulties may arise owing to the existence of a layer of metal oxide on the surface of the rod, which leads to the introduction of impurities into the levitated mass and hence into the final product.
The third aspect of the invention seeks to provide a method of removing aluminium oxide films from aluminium metal which method can be combined conveniently with the apparatus according to the second aspect of the invention.
According to the third aspect of the invention a method of stripping an aluminium oxide (Al203) film from an aluminium metal rod comprises supporting an aluminium metal rod from both ends in an evacuated reaction zone, providing local heating in one region of the reaction zone to melt the surface portion of the aluminium rod in that region and cause the Awl203 film on that portion of the rod to react with aluminium to form volatile aluminium sub-oxide (A120), which is evacuated, effecting relative movement between the local heating region and the aluminium rod to strip the Awl203 film from the rod along at least part of its length in the reaction zone without destroying the rod, and maintaining the stripped rod under oxygen-free conditions.
This method may be combined with the apparatus according to the second aspect and the method according to the first aspect of the invention by using the same reaction zone in each case and maintaining oxygen-free conditions throughout.
The reaction of the Awl203 film with aluminium metal occurs at temperatures above 1 2000C according to the equation Awl203 + 4AI = 3at20 and the local heating must be sufficient for this purpose without destroying the entire structure of the rod. Conveniently the local heating is provided by electro-magnetic induction.
The invention is further illustrated in the accompanying drawings, in which
Fig. 1 is a diagrammatic sketch of apparatus suitable for performing the invention in its first
aspect,
Fig. 2 is a diagrammatic sketch of apparatus
according to the invention in its second aspect,
and
Fig. 3 is a diagrammatic sketch of apparatus
suitable for performing the invention in its third
aspect.
Referring to Fig. 1 of the drawings, the
apparatus comprises a vertical reaction tube 100
of silica fitted with a cooling jacket 101 for the
circulation of cooling water between an inlet 102
and an outlet 103 and with a water-cooled end
cap 104 of stainless steel. An inlet 105 for a
gaseous mixture of nitrogen and helium is
provided in the base of the tube and a lateral
outlet 106 removes gaseous products and
residual gas to a cyclone separator or other dust
catcher 108 where waste gas is separated and
removed overhead at 109, product falling into an
oxygen-free handling enclosure 110 for recovery
or use. A radio-frequency levitation coil 111 .surrounds the reaction tube 101 just below the
outlet 106 and a charge of molten aluminium 112
is maintained in the levitation field for conversion
into aluminium nitride.This charge may be
supplied or supplemented via retractable
pedestal 113.
Referring to Fig. 2 of the drawings a vertical
reaction tube 201 (which may be identical with
the reaction tube 101 of Fig. 1) is equipped with a
radio-frequency levitation coil 202 (which may be
identical with the coil 112 of Fig. 1) able to
maintain a molten charge 203, for example of
aluminium. A sensor 204 in the form of a
television camera is positioned to take pictures of
the charge 203 and this controls, via integrator
205, control amplifier 206 and power controller
207, an electrically driven mechanical feed 208.
The feed 208 drives a vertical stainless steel
driving rod 209, passing through a sliding seal
(not shown) and a stainless steel end cap 210,
into a stainless steel tube 211 attached below the
reaction tube 201. The driving rod 209 terminates
inside the tube 211 in a silica insulator 212 which
carries a chuck 213 which in turn carries a metal
rod 21 4 to provide replenishment for the charge
203. Movement of the rod 214 into the field
generated by the levitation coil 202 is governed by
the size of the charge 203 observed by the
sensor 204.
Referring now to Fig. 3 of the drawings, a
vertical reaction tube 301 (which may be identical
with the tubes 101 and 201) is evacuated via
outlet 302 and is fitted with an induction heating
coil 303 (which may be identical with the
levitation coil 112 and 202). An aluminium rod
304 passes vertically through the reaction tube
301 and its end caps 305 and 306, the upper of
which is provided with a gate valve 307, and into
stainless steel tubes 308 and 309 above and
below the reaction tube 301. At each end it is
mounted in an insulated chuck 310,311 and the
upper chuck supports a refractory dump tube 31 2 running externally of the rod 304 down to the
lower chuck.Support rods 31 3 and 314 extend beyond the chucks 310,311 and are driven by means (not shown) enabling the rod 304 to move vertically relative to the coil 303.
To use the apparatus the rod 304 is moved to its uppermost position with the bottom of the rod (adjacent to the chuck 311) in the heating field provided by the coil 303 and the system is evacuated. The coil is then switched on and the surface of the rod 304 in the region of the coil is rendered molten to provide a "floating" molten zone 31 5 and strip off the Awl203 layer as volatile A120 which is removed via the outlet 302. The system of rods 313,304 and 314 is then moved downwards until the top end of the rod 304 is in the region of the coil 303, the "floating" molten zone 31 5 rising up the rod to strip off the Al203 layer along its entire length. The lower support rod 314 is then held stationary whilst the upper support rod 313 is moved upwards, thus causing the rod 304 to break in the region of the "floating" molten zone 31 5. The upper chuck 310 and dump tube 312 are lifted into the upper tube 308 and isolated by closing the gate valve 307. Melting in the region of the coil 303 is completed and the rod is ready for use, for example according to the procedure described above in connection with
Figs. 1 and 2.
Claims (14)
1. A process for the manufacture of high-purity aluminium nitride comprising levitating a charge of molten aluminium in a reaction zone by means of electromagnetic induction in a levitation coil in an oxygen-free atmosphere, reacting the levitated molten aluminium at a functionally effective temperature with nitrogen gas and recovering the resulting aluminium nitride in an oxygen-free atmosphere.
2. A process as claimed in claim 1 wherein the reaction is carried out at a temperature of from
1800 to 23000 C.
3. A process as claimed in claim 1 wherein the reaction is carried out at a temperature of about 20000C.
4. A process as claimed in any of claims 1 to 3 wherein the reaction is carried out in the presence of a mixture of nitrogen gas and an inert gas.
5. A process as claimed in claim 4 wherein the
proportion of nitrogen gas and inert gas is varied
in response to changes in the temperature and
rate of reaction in order to maintain substantially
constant temperature and reaction rate.
6. A process as claimed in any of claims 1 to 5
wherein the levitated charge of molten aluminium
is replenished during the reaction by sensing the
size of the remaining charge with a sensor and
protruding an additional quantity of aluminium
into the levitation field under the control of the
sensor in order to maintain a constant size of the
levitated charge.
7. A process as claimed in claim 6 wherein the charge is replenished from a solid aluminium rod one end of which is protruded into the levitation field under the control of the sensor whereupon it melts.
8. A process as claimed in any of claims 1 to 7 wherein the aluminium for the reaction is freed from a surface Al203 film by heating solid aluminium in an evacuated reaction zone to cause the surface of the aluminium to melt and the surface Awl203 film thereon to react with aluminium to form Awl20 which is evacuated, and the thus purified aluminium is maintained under oxygenfree conditions until levitated.
9. A process as claimed in claim 8 wherein the heating of the aluminium is carried out by electromagnetic induction to a temperature above 12000C.
1 0. A process for the manufacture of high purity aluminium nitride carried out substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawings.
11. Apparatus for use in carrying out reaction between a levitated mass of molten aluminium and gaseous nitrogen to produce gaseous aluminium nitride, comprising a reaction zone having an inlet for gaseous nitrogen and an outlet for gaseous aluminium nitride, and a levitation coil arranged to levitate the mass of molten aluminium in the reaction zone.
12. Apparatus as claimed in claim 11 including an automatic sensor for sensing the size of the levitated mass and drive means, controlled by the sensor, for protruding an additional quantity of aluminium into the levitation field generated by the levitation coil to replenish the levitated mass.
13. Apparatus as claimed in claim 11 and substantially as hereinbefore described or illustrated in Figure 1 or Figure 2 of the accompanying drawings.
14. A method of stripping an Awl203 film from an aluminium metal rod to be used in a process as claimed in claim 1, comprising supporting the aluminium metal rod from both ends in an evacuated reaction zone, providing local heating in one region of the reaction zone to melt the surface portion of the rod in that region and cause the
Al203 film on that portion of the rod to react with aluminium to form volatile Al2O, which is evacuated, effecting relative movement between the local heating region and the aluminium rod to strip the Awl203 film from the rod along at least part of its length in the reaction zone without destroying the rod, and maintaining the stripped rod under oxygen-free conditions until it is used in a process as claimed in claim 1.
1 5. A method as claimed in claim 14 carried out in apparatus substantially as hereinbefore described or illustrated in Figure 3 of the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08228522A GB2127709A (en) | 1982-10-06 | 1982-10-06 | Manufacture of aluminium nitride |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08228522A GB2127709A (en) | 1982-10-06 | 1982-10-06 | Manufacture of aluminium nitride |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2127709A true GB2127709A (en) | 1984-04-18 |
Family
ID=10533418
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08228522A Withdrawn GB2127709A (en) | 1982-10-06 | 1982-10-06 | Manufacture of aluminium nitride |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2127709A (en) |
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4713360A (en) * | 1984-03-16 | 1987-12-15 | Lanxide Technology Company, Lp | Novel ceramic materials and methods for making same |
| US4853352A (en) * | 1984-07-20 | 1989-08-01 | Lanxide Technology Company, Lp | Method of making self-supporting ceramic materials and materials made thereby |
| US4859640A (en) * | 1986-08-13 | 1989-08-22 | Lanxide Technology Company, Lp | Method of making ceramic composite articles with shape replicated surfaces |
| GB2215714A (en) * | 1988-03-18 | 1989-09-27 | Vaw Ver Aluminium Werke Ag | Tubular reactor for the high-temperature decomposition of bauxite |
| US4923832A (en) * | 1986-05-08 | 1990-05-08 | Lanxide Technology Company, Lp | Method of making shaped ceramic composites with the use of a barrier |
| US5017526A (en) * | 1986-05-08 | 1991-05-21 | Lanxide Technology Company, Lp | Methods of making shaped ceramic composites |
| US5077245A (en) * | 1987-01-30 | 1991-12-31 | Kyocera Corporation | Aluminum nitride-based sintered body and process for the production thereof |
| US5154863A (en) * | 1985-10-31 | 1992-10-13 | Kyocera Corporation | Aluminum nitride-based sintered body and process for the production thereof |
| US5212124A (en) * | 1986-08-13 | 1993-05-18 | Lanxide Technology Company, Lp | Ceramic composite articles with shape replicated surfaces |
| US5236786A (en) * | 1986-05-08 | 1993-08-17 | Lanxide Technology Company, Lp | Shaped ceramic composites with a barrier |
| WO1993014027A3 (en) * | 1992-01-10 | 1993-10-14 | Dow Chemical Co | Process for preparing ultrafine aluminum nitride powder |
| US5306677A (en) * | 1984-03-16 | 1994-04-26 | Lanxide Technology Company, Lp | Ceramic materials |
| US5306676A (en) * | 1993-03-09 | 1994-04-26 | Lanxide Technology Company, Lp | Silicon carbide bodies and methods of making the same |
| US5314850A (en) * | 1985-10-31 | 1994-05-24 | Kyocera Corporation | Aluminum nitride sintered body and production thereof |
| US5340655A (en) * | 1986-05-08 | 1994-08-23 | Lanxide Technology Company, Lp | Method of making shaped ceramic composites with the use of a barrier and articles produced thereby |
| US5358914A (en) * | 1986-05-08 | 1994-10-25 | Lanxide Technology Company, Lp | Methods of making shaped ceramic composites |
| GB2326160A (en) * | 1997-06-11 | 1998-12-16 | Hitachi Cable | Making group III metal nitride crystals; crystal growth methods |
| RU2312060C2 (en) * | 2005-01-28 | 2007-12-10 | Общество с ограниченной ответственностью "Центр научно-технических разработок" (ООО "Центр научно-технических разработок") | Method for preparing aluminum nitride powder |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB711034A (en) * | 1950-01-04 | 1954-06-23 | Nat Res Dev | Apparatus for the treatment of fluids comprising a bed of particulate material |
| GB1103633A (en) * | 1965-08-13 | 1968-02-21 | Tokyo Shibaura Electric Co | Preparation of molded and sintered aluminium nitride |
| GB2057910A (en) * | 1979-09-07 | 1981-04-08 | Exxon Research Engineering Co | A process for the separation of contaminants from feed streams using magnetic beds |
-
1982
- 1982-10-06 GB GB08228522A patent/GB2127709A/en not_active Withdrawn
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB711034A (en) * | 1950-01-04 | 1954-06-23 | Nat Res Dev | Apparatus for the treatment of fluids comprising a bed of particulate material |
| GB1103633A (en) * | 1965-08-13 | 1968-02-21 | Tokyo Shibaura Electric Co | Preparation of molded and sintered aluminium nitride |
| GB2057910A (en) * | 1979-09-07 | 1981-04-08 | Exxon Research Engineering Co | A process for the separation of contaminants from feed streams using magnetic beds |
Cited By (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4713360A (en) * | 1984-03-16 | 1987-12-15 | Lanxide Technology Company, Lp | Novel ceramic materials and methods for making same |
| US5306677A (en) * | 1984-03-16 | 1994-04-26 | Lanxide Technology Company, Lp | Ceramic materials |
| US4853352A (en) * | 1984-07-20 | 1989-08-01 | Lanxide Technology Company, Lp | Method of making self-supporting ceramic materials and materials made thereby |
| US5154863A (en) * | 1985-10-31 | 1992-10-13 | Kyocera Corporation | Aluminum nitride-based sintered body and process for the production thereof |
| US5314850A (en) * | 1985-10-31 | 1994-05-24 | Kyocera Corporation | Aluminum nitride sintered body and production thereof |
| US5356720A (en) * | 1986-05-08 | 1994-10-18 | Lanxide Technology Company, Lp | Shaped self-supporting ceramic composite bodies comprising silicon nitrides |
| US5358914A (en) * | 1986-05-08 | 1994-10-25 | Lanxide Technology Company, Lp | Methods of making shaped ceramic composites |
| US5017526A (en) * | 1986-05-08 | 1991-05-21 | Lanxide Technology Company, Lp | Methods of making shaped ceramic composites |
| US5236786A (en) * | 1986-05-08 | 1993-08-17 | Lanxide Technology Company, Lp | Shaped ceramic composites with a barrier |
| US4923832A (en) * | 1986-05-08 | 1990-05-08 | Lanxide Technology Company, Lp | Method of making shaped ceramic composites with the use of a barrier |
| US5436209A (en) * | 1986-05-08 | 1995-07-25 | Lanxide Technology Company, Lp | Set up for making shaped ceramic composites with the use of a barrier means and articles produced thereby |
| US5340655A (en) * | 1986-05-08 | 1994-08-23 | Lanxide Technology Company, Lp | Method of making shaped ceramic composites with the use of a barrier and articles produced thereby |
| US5212124A (en) * | 1986-08-13 | 1993-05-18 | Lanxide Technology Company, Lp | Ceramic composite articles with shape replicated surfaces |
| US4859640A (en) * | 1986-08-13 | 1989-08-22 | Lanxide Technology Company, Lp | Method of making ceramic composite articles with shape replicated surfaces |
| US5077245A (en) * | 1987-01-30 | 1991-12-31 | Kyocera Corporation | Aluminum nitride-based sintered body and process for the production thereof |
| GB2215714A (en) * | 1988-03-18 | 1989-09-27 | Vaw Ver Aluminium Werke Ag | Tubular reactor for the high-temperature decomposition of bauxite |
| WO1993014027A3 (en) * | 1992-01-10 | 1993-10-14 | Dow Chemical Co | Process for preparing ultrafine aluminum nitride powder |
| US5306676A (en) * | 1993-03-09 | 1994-04-26 | Lanxide Technology Company, Lp | Silicon carbide bodies and methods of making the same |
| US5436208A (en) * | 1993-03-09 | 1995-07-25 | Lanxide Technology Company, Lp | Silicon carbide bodies and methods of making the same |
| GB2326160A (en) * | 1997-06-11 | 1998-12-16 | Hitachi Cable | Making group III metal nitride crystals; crystal growth methods |
| GB2326160B (en) * | 1997-06-11 | 1999-11-03 | Hitachi Cable | Nitride crystal fabricating method |
| RU2312060C2 (en) * | 2005-01-28 | 2007-12-10 | Общество с ограниченной ответственностью "Центр научно-технических разработок" (ООО "Центр научно-технических разработок") | Method for preparing aluminum nitride powder |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| GB2127709A (en) | Manufacture of aluminium nitride | |
| EP0045599B1 (en) | Process and apparatus for the production of silicon bodies by continuous chemical vapor deposition | |
| CA1102886A (en) | Arc heater method for the production of single crystal silicon | |
| US4200621A (en) | Sequential purification and crystal growth | |
| US3265469A (en) | Crystal growing apparatus | |
| JPS63149337A (en) | Method for induction melting of reactive metal charge | |
| EP1754806A1 (en) | Method for casting polycrystalline silicon | |
| US3012865A (en) | Silicon purification process | |
| NO171778B (en) | PROCEDURE FOR REFINING SILICONE | |
| EP0454151A1 (en) | Manufacturing method of silicon single-crystal | |
| US4676968A (en) | Melt consolidation of silicon powder | |
| US5458669A (en) | Process for purification of gallium material | |
| US3156549A (en) | Method of melting silicon | |
| WO2007119605A1 (en) | Method and apparatus for producing silicon | |
| US3226203A (en) | Apparatus for preparing semiconductor rods | |
| US2985519A (en) | Production of silicon | |
| JPH05262512A (en) | Silicon refining method | |
| US3899304A (en) | Process of growing crystals | |
| US4877596A (en) | Process for the production of low carbon silicon | |
| US2990261A (en) | Processing of boron compact | |
| US3055741A (en) | Method for producing silicon | |
| US2758831A (en) | Lined metal reduction apparatus | |
| US3505025A (en) | Jacketed,cooled crucible for crystallizing material | |
| CA1043534A (en) | Process for the production of iii a - v b compounds | |
| WO1980001489A1 (en) | Cold crucible semiconductor deposition process and apparatus |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |