CA1240569A - Process for the germanium-doping of optical waveguide base material based on vitreous silica - Google Patents
Process for the germanium-doping of optical waveguide base material based on vitreous silicaInfo
- Publication number
- CA1240569A CA1240569A CA000470555A CA470555A CA1240569A CA 1240569 A CA1240569 A CA 1240569A CA 000470555 A CA000470555 A CA 000470555A CA 470555 A CA470555 A CA 470555A CA 1240569 A CA1240569 A CA 1240569A
- Authority
- CA
- Canada
- Prior art keywords
- germanium
- doping
- vitreous silica
- optical waveguide
- base material
- 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.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C13/00—Fibre or filament compositions
- C03C13/04—Fibre optics, e.g. core and clad fibre compositions
- C03C13/045—Silica-containing oxide glass compositions
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/012—Manufacture of preforms for drawing fibres or filaments
- C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
- C03B37/01413—Reactant delivery systems
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/30—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi
- C03B2201/31—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi doped with germanium
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
- Glass Compositions (AREA)
- Silicon Compounds (AREA)
- Chemical Vapour Deposition (AREA)
Abstract
PROCESS FOR THE GERMANIUM-DOPING OF OPTICAL WAVEGUIDE BASE MATERIAL BASED ON VITREOUS SILICA ABSTRACT OF THE DISCLOSURE A process is provided which permits the effective manufacture of optical waveguide base material that has been doped with germanium and is based on vitreous silica. According to the invention, silicon chlorides of the formula SinCl2n+2, in which "n" is an integer from 2 to 6 especially hexachlorodi-silane, are used as glass-formers in the presence of oxygen and germanium tetrachloride at temperatures of from 1100 - 1600°C.
Description
6~
The invention relates to a process for the germanium-doping of optical waveguide base material based on vitreoussilica. More particularly, it relates to such a process wherein a gas that can be oxidized to form silica is reacted with oxygen, or with gases that release oxygen under the reaction conditions, in the presence of germanium tetrachloride.
It is known, in optical waveguide technology, how to increase the refractive index of vitreous silica by doping with germanium. For this purpose, in the customary processes, a specific amount of germanium tetrachloride is reacted, simultaneously with the reaction of the vitreous-silica-former silicon tetrachloride, with oxygen, by which means a vitreous silica doped with germanium is finally produced.
During the manufacture of optical waveguide base material, e.g., according to the so-called MCVD (modified chemical vapor deposition~ process at a reaction temperature of greater than 1430C, however, only approximately 20% of the germanium tetrachloride used, in fact, reacts to form GeO2, while approximately 80% remains unreacted.
As i~ explained in a publication of M.P. Bohrer, J.A.
Amelse, P.L. ~arasimham, B.K. Tariyal, J.M. Turnipseed and R.F.
Gill (9th European Conference on Optical Communication, H. Melchior and A. Solberger (editors), Elsevier Science Publishers B.V. (North-Holland), 1983, pages 365-368) and in works cited therein, the cause lies in the unfavorable balance of the equilibrium GeC14 + 2 ' GeO2 + 2C12 s~
which is displaced toward the left in the direction of the volatile GeC14 as a result of high chlorine concentrations, from the reaction of the silicon tetrachloride. Furthermore, only 30 - 40% of the GeC14 which has reacted to form GeO2 is, in fact, deposited as so-called "soot" and can therefore act as dopant. Losses of such magnitude are economically unacceptable in view of the high cost of GeC14.
The above-mentioned publication does indeed describe a process according to which the major part of the unused germanium is recovered from the exhaust flow and, after reprocessing, is reused. This does not alter the fact that the actual reaction of GeC14 to form GeO2 occurs with unsatisfactory yields so that it is still necessary to supply large amounts of expensive GeC14 in order to obtain a relatively small amount of dopant.
This object of the present invention is therefore to provide a process which permits effective germanium-doping of vitreous silica.
The object is accomplished by a process in which silicon chlorides of the formula SinC12n~2, in which 'n' is an integer from 2 to 6 are used as gases to be oxidized to form silica.
Russian application 88 74 63, laid open on December 7, 1981, authors W.F. Kotschubej et al., which relates to the manu-facture of highly dispersed silica of high purity by reacting Si2C16 with oxygen discloses the possibility of using the resulting SiO2 for the manufacture of optical fiber. In that 5~
process, however, the SiO2 occurs in undoped form and, under the conditions mentioned, cannot be effectively doped, and thus cannot be considered for the manufacture of doped vitreous silica.
The doplng process according to the invention can, in principle, be used for all methods which are known to the person skilled in the art and are customarily used for the manufacture of germanium-doped optical waveguide base material based on vitreous silica and in which the doping is effected by the gaseous phase reaction of germanium tetrachloride. Such processes are, e.g., the so-called MCVD (modified chemical vapor deposition~ process, the IVPO (inside vapor phase oxidation) process, the OVPO (outside vapor phase oxidation) process or the VAD (vapor axial deposition) process.
It is also possible to manufacture optical waveguide base material doped with different dopants by carrying out only the germanium-doping according to the process of the invention and using conventional processes, e.g., the reaction of silicon tetrachloride with oxygen in the presence of the particular doping compound selected, for the doping with other dopants, e.g., boron or phosphorus.
When selecting suitable silicon chlorides, two factors, especially, are to be considered. On the one hand, the lower the amount of chlorine released during the formation of quartz from the silicon chlorides, the lower the germanium loss to be expected. Accordingly, it would be desirable to use chlorosilanes that are as rich in silicon as possible, such as g ' 4 110' si5cll2 or Si6C114. On the other hand, it is relatively difficult to convert these halides into a gaseous phase, and therefore their use requires extra experimental equipment, e.g., the use of a vacuum. Such processes are described, e.g., in DE-PS 24 44 100 for SiC14/oxygen at 1-10 Torr and can be appropriately applied also to ch]orosilanes that are richer in silicon.
In the process according to the invention, however, it is preferable to use octachlorotrisilane or, especially, hexachlorodisilane, both of which can be easily converted into the gaseous p~ase owing to their advantageous boiling points and therefore allow a less expensive operating procedure, even though both form a relatively large amount of chloride when reacted.
Silicon chlorides, SinC12n+2, in which "n" is an integer from 2 to 6 especially hexachlorodisilane, occur as by-products in exhaust gases, e.g., during the manufacture of high purity silicon by the decomposition of trichlorosilane on heated substrates or during the conversion of silicon tetrachloride to form trichlorosilane, and they can be separated out from the exhaust gases, e.g., by condensing out, and subsequently be worked up and isolated by distillation. The advantage of this process is that, in addition to using waste products that could not be used hitherto, silicon chlorides having a high purity are obta~ned. For this reason, it is generally preferable to use silicon chlorides that occur in the manufacture of high-purity silicon, rather than silicon chlorides that can be obtained in another manner, e.g., from silicides.
O~i9 Advantageously, the particular silicon chlorides selected are used in the purest form possible, that is to say, if possibLe without the addition of other silicon chlorides, in order to make it possible to achieve an exact adjustment of the silicon amount, i.e., silicon : germanium ratio. Special attention should also be paid to the removal of any fractions containing hydrogen.
During the glass-formation reaction, in which vitreous silica having the desired doping is formed by reactinq silicon chloride, germanium chloride and oxygen, temperatures within the range of 1100 - 1600C are advantageously maintained. They can be adjusted, according to the manufacturing process selected, e.g., by using burners, plasma heating or resistance heating.
The oxygen required for the reaction can be conveyed to the reaction zone in the form of one or more oxygen gas fLows which, at the user's option, may already be charged with the reactants. It is also possible to consider replacing the oxygen, either partially or completely, by other gases that release oxygen under the reaction conditions, e.g., nitrous oxide, nitric monoxide or carbon dioxide. It is also possible to add inert gases, such as nitrogen or argon, e.g., to influence the flow and concentration ratios.
In this connection, it has proven useful to pretreat "auxiliary gases", e.g., helium, neon, argon, nitrogen, oxygen, nitrous oxide, nitric oxide, carbon dioxide, Freons, and halo-gens, used primarily as carrier gases or oxidizing agents in the manufacture of qlass fibers, that are used with D2O according to Canadian Application No. 465,992, filed October 9, 1984, since 5~
in this manner vitreous silica having an especially low OH-content is ohtained.
When manufacturing doped vitreous silica according to the process of the invention it is possible, in principle, to use the procedures which are known for the conventional methods based on silicon tetrachloride. In general, it is sufficient to feed in the selected silicon chloride, preferably hexachlorodi-silane, in place of the SiC14. This can be carried out in a simple manner, e.g., by loading an evaporator provided for char~ing the auxiliary gas, e.g., oxygen, with silicon chloriae preferably Si2C16 or Si3C18 in place of SiC14, and thermostatically heating it to the temperature corresponding to the desired vapor pressure of the silicon chloride selected.
Obv;ously, the proportion of germanium tetrachloride, which is generally conveyed to the reaction zone via a separate, second, gas flow, has to be adapted to the germanium concentration desired in the vitreous silica.
The use according to the invention of silicon chlorides, SinC12n+2, in which "n" is an integer from 2 to 6, especially hexachlorodisilane (n=2), in the manufacture of germanium-doped vitreous silica makes it possible to considerably increase the utilization of the expensive germanium tetrachloride used as a dopant, vis-a-vis the use of silicon tetrachloride, without great additional expenditure on apparatus.
In the following, the invention will be more fully described in an example, but it should be understood that it is given by way of illustration only, and not of limitation.
Example ~ exachlorodisilane, which has been separated, by conaensation and subsequent distillation, from the exhaust gas mixture resulting during the manufacture of high purity elemental silicon by decomposition of trichlorosilane on heated substrates, was placed in an evaporator. An oxygen flow, preheated to 80C, was bubbled through the fluid, maintained at 130C. Into the resulting oxygen flow, saturated with Si2C16, was fed an oxygen flow that had been saturated in an analogous manner with germanium tetrachloride. To prevent condensation of the components, the combined gas flows were conveyed via thermostatically heated lines to the reaction zones, where they were blown through a nozzle into a vitreous silica tube heated to 1500C by means of a tubular furnace. The reaction produced a vitreous silica soot doped with germanium, which was collected in a collecting vessel.
During the course of the reaction, a total of 150 ml of Si2C16 and 80 ml of GeC14, corresponding to a molar ratio of 1 : 0.77, was reacted with an approximately two-fold excess of oxygen. 126 g of a pulverulent substance, which could be sintered to form a glass article and which contained 9.9 mole-% of GeO2 (corresponding to a mixture of 22 g of GeO2 and 104 g of SiO2), were isolated. The resulting yield of SiO2 was 98.2%, based on the Si2C16 used, and the yield of GeO2 was 27.9%, based on the GeC14 used.
In a comparison test, a mixture of silicon tetrachloride and germanium tetrachloride having the same Si/Ge ratio (molar ratio 2 : 0.77) was reacted with an approximately two-fold excess of oxygen, under conditions which were otherwise 5~9 identical. The resulting product had a content oE 7.2 mole-% of GeO2. The yie].d of SiO2 was 96.0%, based on the SiC14 used, while the yield of GeO2, based on the GeC14 used, was only 19.5%.
Thus, while only several embodiments and an example of the present invention have been described, it will be obvious that many changes and modifications may be made thereto, without departing from the spirit and scope of the invention.
The invention relates to a process for the germanium-doping of optical waveguide base material based on vitreoussilica. More particularly, it relates to such a process wherein a gas that can be oxidized to form silica is reacted with oxygen, or with gases that release oxygen under the reaction conditions, in the presence of germanium tetrachloride.
It is known, in optical waveguide technology, how to increase the refractive index of vitreous silica by doping with germanium. For this purpose, in the customary processes, a specific amount of germanium tetrachloride is reacted, simultaneously with the reaction of the vitreous-silica-former silicon tetrachloride, with oxygen, by which means a vitreous silica doped with germanium is finally produced.
During the manufacture of optical waveguide base material, e.g., according to the so-called MCVD (modified chemical vapor deposition~ process at a reaction temperature of greater than 1430C, however, only approximately 20% of the germanium tetrachloride used, in fact, reacts to form GeO2, while approximately 80% remains unreacted.
As i~ explained in a publication of M.P. Bohrer, J.A.
Amelse, P.L. ~arasimham, B.K. Tariyal, J.M. Turnipseed and R.F.
Gill (9th European Conference on Optical Communication, H. Melchior and A. Solberger (editors), Elsevier Science Publishers B.V. (North-Holland), 1983, pages 365-368) and in works cited therein, the cause lies in the unfavorable balance of the equilibrium GeC14 + 2 ' GeO2 + 2C12 s~
which is displaced toward the left in the direction of the volatile GeC14 as a result of high chlorine concentrations, from the reaction of the silicon tetrachloride. Furthermore, only 30 - 40% of the GeC14 which has reacted to form GeO2 is, in fact, deposited as so-called "soot" and can therefore act as dopant. Losses of such magnitude are economically unacceptable in view of the high cost of GeC14.
The above-mentioned publication does indeed describe a process according to which the major part of the unused germanium is recovered from the exhaust flow and, after reprocessing, is reused. This does not alter the fact that the actual reaction of GeC14 to form GeO2 occurs with unsatisfactory yields so that it is still necessary to supply large amounts of expensive GeC14 in order to obtain a relatively small amount of dopant.
This object of the present invention is therefore to provide a process which permits effective germanium-doping of vitreous silica.
The object is accomplished by a process in which silicon chlorides of the formula SinC12n~2, in which 'n' is an integer from 2 to 6 are used as gases to be oxidized to form silica.
Russian application 88 74 63, laid open on December 7, 1981, authors W.F. Kotschubej et al., which relates to the manu-facture of highly dispersed silica of high purity by reacting Si2C16 with oxygen discloses the possibility of using the resulting SiO2 for the manufacture of optical fiber. In that 5~
process, however, the SiO2 occurs in undoped form and, under the conditions mentioned, cannot be effectively doped, and thus cannot be considered for the manufacture of doped vitreous silica.
The doplng process according to the invention can, in principle, be used for all methods which are known to the person skilled in the art and are customarily used for the manufacture of germanium-doped optical waveguide base material based on vitreous silica and in which the doping is effected by the gaseous phase reaction of germanium tetrachloride. Such processes are, e.g., the so-called MCVD (modified chemical vapor deposition~ process, the IVPO (inside vapor phase oxidation) process, the OVPO (outside vapor phase oxidation) process or the VAD (vapor axial deposition) process.
It is also possible to manufacture optical waveguide base material doped with different dopants by carrying out only the germanium-doping according to the process of the invention and using conventional processes, e.g., the reaction of silicon tetrachloride with oxygen in the presence of the particular doping compound selected, for the doping with other dopants, e.g., boron or phosphorus.
When selecting suitable silicon chlorides, two factors, especially, are to be considered. On the one hand, the lower the amount of chlorine released during the formation of quartz from the silicon chlorides, the lower the germanium loss to be expected. Accordingly, it would be desirable to use chlorosilanes that are as rich in silicon as possible, such as g ' 4 110' si5cll2 or Si6C114. On the other hand, it is relatively difficult to convert these halides into a gaseous phase, and therefore their use requires extra experimental equipment, e.g., the use of a vacuum. Such processes are described, e.g., in DE-PS 24 44 100 for SiC14/oxygen at 1-10 Torr and can be appropriately applied also to ch]orosilanes that are richer in silicon.
In the process according to the invention, however, it is preferable to use octachlorotrisilane or, especially, hexachlorodisilane, both of which can be easily converted into the gaseous p~ase owing to their advantageous boiling points and therefore allow a less expensive operating procedure, even though both form a relatively large amount of chloride when reacted.
Silicon chlorides, SinC12n+2, in which "n" is an integer from 2 to 6 especially hexachlorodisilane, occur as by-products in exhaust gases, e.g., during the manufacture of high purity silicon by the decomposition of trichlorosilane on heated substrates or during the conversion of silicon tetrachloride to form trichlorosilane, and they can be separated out from the exhaust gases, e.g., by condensing out, and subsequently be worked up and isolated by distillation. The advantage of this process is that, in addition to using waste products that could not be used hitherto, silicon chlorides having a high purity are obta~ned. For this reason, it is generally preferable to use silicon chlorides that occur in the manufacture of high-purity silicon, rather than silicon chlorides that can be obtained in another manner, e.g., from silicides.
O~i9 Advantageously, the particular silicon chlorides selected are used in the purest form possible, that is to say, if possibLe without the addition of other silicon chlorides, in order to make it possible to achieve an exact adjustment of the silicon amount, i.e., silicon : germanium ratio. Special attention should also be paid to the removal of any fractions containing hydrogen.
During the glass-formation reaction, in which vitreous silica having the desired doping is formed by reactinq silicon chloride, germanium chloride and oxygen, temperatures within the range of 1100 - 1600C are advantageously maintained. They can be adjusted, according to the manufacturing process selected, e.g., by using burners, plasma heating or resistance heating.
The oxygen required for the reaction can be conveyed to the reaction zone in the form of one or more oxygen gas fLows which, at the user's option, may already be charged with the reactants. It is also possible to consider replacing the oxygen, either partially or completely, by other gases that release oxygen under the reaction conditions, e.g., nitrous oxide, nitric monoxide or carbon dioxide. It is also possible to add inert gases, such as nitrogen or argon, e.g., to influence the flow and concentration ratios.
In this connection, it has proven useful to pretreat "auxiliary gases", e.g., helium, neon, argon, nitrogen, oxygen, nitrous oxide, nitric oxide, carbon dioxide, Freons, and halo-gens, used primarily as carrier gases or oxidizing agents in the manufacture of qlass fibers, that are used with D2O according to Canadian Application No. 465,992, filed October 9, 1984, since 5~
in this manner vitreous silica having an especially low OH-content is ohtained.
When manufacturing doped vitreous silica according to the process of the invention it is possible, in principle, to use the procedures which are known for the conventional methods based on silicon tetrachloride. In general, it is sufficient to feed in the selected silicon chloride, preferably hexachlorodi-silane, in place of the SiC14. This can be carried out in a simple manner, e.g., by loading an evaporator provided for char~ing the auxiliary gas, e.g., oxygen, with silicon chloriae preferably Si2C16 or Si3C18 in place of SiC14, and thermostatically heating it to the temperature corresponding to the desired vapor pressure of the silicon chloride selected.
Obv;ously, the proportion of germanium tetrachloride, which is generally conveyed to the reaction zone via a separate, second, gas flow, has to be adapted to the germanium concentration desired in the vitreous silica.
The use according to the invention of silicon chlorides, SinC12n+2, in which "n" is an integer from 2 to 6, especially hexachlorodisilane (n=2), in the manufacture of germanium-doped vitreous silica makes it possible to considerably increase the utilization of the expensive germanium tetrachloride used as a dopant, vis-a-vis the use of silicon tetrachloride, without great additional expenditure on apparatus.
In the following, the invention will be more fully described in an example, but it should be understood that it is given by way of illustration only, and not of limitation.
Example ~ exachlorodisilane, which has been separated, by conaensation and subsequent distillation, from the exhaust gas mixture resulting during the manufacture of high purity elemental silicon by decomposition of trichlorosilane on heated substrates, was placed in an evaporator. An oxygen flow, preheated to 80C, was bubbled through the fluid, maintained at 130C. Into the resulting oxygen flow, saturated with Si2C16, was fed an oxygen flow that had been saturated in an analogous manner with germanium tetrachloride. To prevent condensation of the components, the combined gas flows were conveyed via thermostatically heated lines to the reaction zones, where they were blown through a nozzle into a vitreous silica tube heated to 1500C by means of a tubular furnace. The reaction produced a vitreous silica soot doped with germanium, which was collected in a collecting vessel.
During the course of the reaction, a total of 150 ml of Si2C16 and 80 ml of GeC14, corresponding to a molar ratio of 1 : 0.77, was reacted with an approximately two-fold excess of oxygen. 126 g of a pulverulent substance, which could be sintered to form a glass article and which contained 9.9 mole-% of GeO2 (corresponding to a mixture of 22 g of GeO2 and 104 g of SiO2), were isolated. The resulting yield of SiO2 was 98.2%, based on the Si2C16 used, and the yield of GeO2 was 27.9%, based on the GeC14 used.
In a comparison test, a mixture of silicon tetrachloride and germanium tetrachloride having the same Si/Ge ratio (molar ratio 2 : 0.77) was reacted with an approximately two-fold excess of oxygen, under conditions which were otherwise 5~9 identical. The resulting product had a content oE 7.2 mole-% of GeO2. The yie].d of SiO2 was 96.0%, based on the SiC14 used, while the yield of GeO2, based on the GeC14 used, was only 19.5%.
Thus, while only several embodiments and an example of the present invention have been described, it will be obvious that many changes and modifications may be made thereto, without departing from the spirit and scope of the invention.
Claims (3)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In a process for the germanium-doping of optical waveguide base material based on vitreous silica, of the type including the step of reacting with oxygen a gas selected from the group consisting of a gas that can be oxidized to form silica, a gas that releases oxygen under reaction conditions and a combination thereof, in the presence of germanium tetrachloride, the improvement comprising the steps of:
using silicon chlorides of the generalized formula SinCl2n+2, wherein "n" is an integer from 2 to 6 as the gas to be oxidized to form silica.
using silicon chlorides of the generalized formula SinCl2n+2, wherein "n" is an integer from 2 to 6 as the gas to be oxidized to form silica.
2. The process as defined in Claim 1, wherein hexachlorodisilane is used as the gas to be oxidized to form silica.
3. The process as defined in claim 1, wherein a reaction temperature of from 1100 - 1600°C is maintained.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3402318.6 | 1984-01-24 | ||
| DE19843402318 DE3402318A1 (en) | 1984-01-24 | 1984-01-24 | METHOD FOR DOPING LIGHT WAVE BASE MATERIAL ON QUARTZ GLASS BASE WITH GERMANIUM |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1240569A true CA1240569A (en) | 1988-08-16 |
Family
ID=6225750
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000470555A Expired CA1240569A (en) | 1984-01-24 | 1984-12-19 | Process for the germanium-doping of optical waveguide base material based on vitreous silica |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0150069B1 (en) |
| JP (1) | JPS60210542A (en) |
| AT (1) | ATE38508T1 (en) |
| AU (1) | AU3802385A (en) |
| CA (1) | CA1240569A (en) |
| DE (2) | DE3402318A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3518620A1 (en) * | 1985-05-23 | 1986-11-27 | Wacker-Chemitronic Gesellschaft für Elektronik-Grundstoffe mbH, 8263 Burghausen | Process for the preparation of an optical waveguide base material based on quartz glass |
| DE102006034061A1 (en) * | 2006-07-20 | 2008-01-24 | REV Renewable Energy Ventures, Inc., Aloha | Polysilane processing and use |
| DE102006043929B4 (en) | 2006-09-14 | 2016-10-06 | Spawnt Private S.À.R.L. | Process for the preparation of solid polysilane mixtures |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5521059A (en) * | 1978-07-31 | 1980-02-14 | Nippon Telegr & Teleph Corp <Ntt> | Optical fiber |
-
1984
- 1984-01-24 DE DE19843402318 patent/DE3402318A1/en not_active Withdrawn
- 1984-10-16 JP JP59215292A patent/JPS60210542A/en active Granted
- 1984-12-19 CA CA000470555A patent/CA1240569A/en not_active Expired
-
1985
- 1985-01-22 AT AT85100576T patent/ATE38508T1/en not_active IP Right Cessation
- 1985-01-22 DE DE8585100576T patent/DE3566109D1/en not_active Expired
- 1985-01-22 EP EP85100576A patent/EP0150069B1/en not_active Expired
- 1985-01-23 AU AU38023/85A patent/AU3802385A/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| EP0150069B1 (en) | 1988-11-09 |
| AU3802385A (en) | 1985-08-01 |
| JPH0218295B2 (en) | 1990-04-25 |
| EP0150069A3 (en) | 1986-05-21 |
| JPS60210542A (en) | 1985-10-23 |
| ATE38508T1 (en) | 1988-11-15 |
| EP0150069A2 (en) | 1985-07-31 |
| DE3402318A1 (en) | 1985-07-25 |
| DE3566109D1 (en) | 1988-12-15 |
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