US2197497A - Selenium rectifier and method of producing same - Google Patents
Selenium rectifier and method of producing same Download PDFInfo
- Publication number
- US2197497A US2197497A US277792A US27779239A US2197497A US 2197497 A US2197497 A US 2197497A US 277792 A US277792 A US 277792A US 27779239 A US27779239 A US 27779239A US 2197497 A US2197497 A US 2197497A
- Authority
- US
- United States
- Prior art keywords
- selenium
- layer
- dioxide
- rectifier
- vapour
- 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 - Lifetime
Links
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 title description 59
- 229910052711 selenium Inorganic materials 0.000 title description 59
- 239000011669 selenium Substances 0.000 title description 59
- 238000000034 method Methods 0.000 title description 20
- JPJALAQPGMAKDF-UHFFFAOYSA-N selenium dioxide Chemical compound O=[Se]=O JPJALAQPGMAKDF-UHFFFAOYSA-N 0.000 description 64
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 14
- 230000015572 biosynthetic process Effects 0.000 description 10
- 230000000903 blocking effect Effects 0.000 description 10
- 239000010408 film Substances 0.000 description 10
- 239000010409 thin film Substances 0.000 description 10
- 238000000151 deposition Methods 0.000 description 8
- 239000002184 metal Substances 0.000 description 8
- 229910052751 metal Inorganic materials 0.000 description 8
- 229910052742 iron Inorganic materials 0.000 description 7
- 238000005507 spraying Methods 0.000 description 7
- 238000010438 heat treatment Methods 0.000 description 6
- 230000008020 evaporation Effects 0.000 description 5
- 238000001704 evaporation Methods 0.000 description 5
- 239000000470 constituent Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000002485 combustion reaction Methods 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000002068 genetic effect Effects 0.000 description 1
- 239000004922 lacquer Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- QYHFIVBSNOWOCQ-UHFFFAOYSA-N selenic acid Chemical compound O[Se](O)(=O)=O QYHFIVBSNOWOCQ-UHFFFAOYSA-N 0.000 description 1
- 229940065287 selenium compound Drugs 0.000 description 1
- 150000003343 selenium compounds Chemical class 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/06—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials
- H01L21/10—Preliminary treatment of the selenium or tellurium, its application to the foundation plate, or the subsequent treatment of the combination
- H01L21/108—Provision of discrete insulating layers, i.e. non-genetic barrier layers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S205/00—Electrolysis: processes, compositions used therein, and methods of preparing the compositions
- Y10S205/917—Treatment of workpiece between coating steps
Definitions
- the present invention briefly relates to rectified devices, and more particularly to selenium rectifiers and methods of producing same.
- the object of our invention is to produce a selenium rectifier'in which the blocking layer formed on the selenium layer of such device involvessuperior properties over the blocking layers heretofore known in the art. This is achieved in accordance with the method proposed by this invention by depositing on the layer of selenium forming part of a selenium rectifier a thin film of selenium dioxide by evaporation before the electrode overlying the selenium layer is applied in a spraying operation.
- a still superior improvement upon the blocking layer will be obtained according to a further feature of this invention when in addition to the deposition of the selenium dioxide also aqueous vapour is applied to the superficies of the selenium.
- a layer of selenium intimately united with a nickel-plated base member of iron in any manner well known in the art and subsequently converted into its grey crystalline state in a heat treatment is held, either manually or by the agency of a supporting device, at a given space from a source of selenium dioxide vapour.
- the selenium dioxide is then deposited in the form of a thin film on the free surface of the selenium; whereupon this film is coated by spraying thereon a metal forming the counter electrode of the 5 rectifier device.
- the so prepared rectifier cell or valve is thereafter treated inan electric formation during the course of which the formation voltage applied across-the cell or valve is gradually increased to approximately 20 volts proportional to the decreasing back current in response to the progressive improvement of the blocking layer during the formation.
- a rectified blocking layer may be still more im- 20 proved when aqueous vapour is applied to the selenium layer simultaneously with the deposition of the selenium dioxide on the free surface thereof.
- the aqueous vapour may be added to the surface of the selenium layer in a variety of different manners.
- the simplest method which has 30 been found satisfactory in many cases comprises heating an amount of seleniumdioxide in a flame whose products of combustion include a large quantity of. aqueous vapour, and so exposing the selenium layer to the resultant gases that the 85 aqueous vapour and the vapour of selenium dioxide are simultaneously deposited on the superfices of the selenium layer. It is on the other hand likewise possible to place selenium dioxide in one receptacle and to provide a second re- 40 ceptacle containing water, either about or in the central portion of the first mentioned receptacle and to concurrently cause the contents thereof to evaporate.
- Still a further alternative process of imparting the necessary amount of aqueous vapour to a selenium dioxide film applied to a selenium layer overlying the base plate electrode is to store the prepared unit in a room which is maintained at a desired degree of moisture.
- the selenium dioxide on account of its hygroscopic nature will then absorb the required quantity of aqueous vapour proportional to the time of such storage.
- the percentage of the constituents selenium dioxide and aqueous vapour to which a selenium layer is to be exposed is determined by the time during which the evaporation is eifective, by the space between the selenium layer and the receptacles containing the elements subject to evaporation and likewise by the intensity thereof. Even if the quantitative amount of evaporation might be raised in response to a temperature augment of the ambient medium, the proper relation of aqueous vapour to the selenium dioxide vapour will be maintained in each and every instant since the former is subjected to a corresponding increase.
- the proper amount of vapour absorption is given by the time during which the prepared rectifier unit is stored in a room of a predetermined degree of humidity.
- the period of time required for depositing the selenium dioxide with or without adding aqueous vapo'ur is equal to few seconds.
- the metallic counter electrode which is preferably sprayed onto the preparatorily finished rectifier is suitably applied immediately after the selenium dioxide and the additional aqueous vapour have been deposited on the superficies of the selenium layer in order to sustain the lenium dioxide during the process as described in the foregoing.
- the method of producing selenium rectifiers which comprises the steps of forming a layer of selenium on one major surface of a nickel-plated iron member, converting the selenium into its grey crystalline state in a heat treatment, depositing a thin film of selenium dioxide on the superficies of the layer of selenium. spraying a layer of metal onto the film of selenium dioxide overlying the selenium, and subjecting the resultant unit to an electric formation process.
- the method of producing selenium rectifiers which comprises the steps of: forming a layer of selenium on one major surface of a nickel-plated iron member, converting the selenium into its grey crystalline state in a heat treatment, depositing a thin film of selenium dioxide on the superficies of the layer of selenium while simultaneously adding aqueous vapour to the selenium dioxide, immediately spraying a layer of metal onto the film of selenium dioxide of given humidity overlying the selenium, and subjecting the resultant unit to an electric formation process.
- the method of producing selenium rectifiers which comprises the steps of: forming a layer of selenium on one major surface of a nickelplated iron member, converting the selenium into its grey crystalline state in a heat treatment, evaporizing a quantity of selenium dioxide in a flame the combustion products of which contain a substantial percentage of aqueous vapour, exposing the grey crystalline selenium layer to the composite mixture of resulting selenium dioxide vapour and aqueous vapour for concurrently depositing the constituents of the mixture on the selenium layer in the shape of a thin film, immediately spraying a layer of metal ontothe film of selenium dioxide of given humidity overlying the selenium, and subjecting the resultant unit to an electric formation process.
- the method of producing selenium rectlflers which comprises the steps of: forming a layer of selenium on one major surface of a nickelplated iron member, converting the selenium into its grey crystalline state in a heat treatment, depositing a thin film of selenium dioxide on the grey crystalline surface of the selenium, imparting the proper percentage of humidity to the selenium dioxide by storing during a predetermined period of time the selenium dioxide film overlying the selenium layer formed on the base member in a room maintained at a given degree of moisture, removing the unit from the storage room, immediately spraying a layer of metal onto the film of selenium dioxide of given humidity, and subjecting the resultant unit to an electric formation process.
- a selenium rectifier comprising a nickel-plated base member of iron acting as an electrode, a grey crystalline layer of selenium formed on the said base member, a thin film of selenium dioxide overlying said layer of selenium, and a layer of metal applied on the said film of selenium dioxide as the counter electrode of said product.
- a selenium rectifier comprising a nickel-plated base member of iron acting as an electrode, a grey crystalline layer of selenium formed on the said base member, a thin film of selenium dioxide of a predetermined percentage of moisture overlying said layer of selenium, and a layer of metal applied on the said film of selenium dioxide as the counter electrode of said product.
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Biotechnology (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Spark Plugs (AREA)
Description
April 16, 1940. o. GEISLER ET AL 2,197,497
1 ayer' of se/eru'u m dioxide sprayed caunf'er e/ecfrode Patented Apr. 16, 194M PATENT orrlca SELENIUM RECTIFIER AND METHOD OF PRODUCING SAME Otmar Geisler and Erich Kipphan, Nuremberg,
Germany, assignors to Siiddeutsche Apparate Fabrik G. 111. b. H., Nuremberg, Germany, a
company Application 1...... 7, 1939, Serial No. 277,792
In Germany June 7, 1938 '6 Claims.
The present invention briefly relates to rectified devices, and more particularly to selenium rectifiers and methods of producing same.
It is a known fact to those skilled in the art that not only the blocking resistance but also the disruptive strength of a blocking layer formed on the upper surface of a selenium layer forming part of a selenium rectifier may be considerably improved in an electric formation process. Although the nature of this blocking layer has not yet been fully investigated, it is believed to be either an extremely thin film of a compound of the selenium with the metal applied thereon as a counter electrode by spraying, or even a thin layer of amorphous selenium.
It belongs to common technical knowledge to apply an artificial blocking layer of a material which stands in no genetic relation to the adjacent electrodes, e. g., a thin coating of lacquer, on the selenium layer of a selenium rectifier. It is also a known expedient to apply by evaporation a second very thin film of selenium on the first selenium layer of a rectifier valve.
The object of our invention is to produce a selenium rectifier'in which the blocking layer formed on the selenium layer of such device involvessuperior properties over the blocking layers heretofore known in the art. This is achieved in accordance with the method proposed by this invention by depositing on the layer of selenium forming part of a selenium rectifier a thin film of selenium dioxide by evaporation before the electrode overlying the selenium layer is applied in a spraying operation.
A still superior improvement upon the blocking layer will be obtained according to a further feature of this invention when in addition to the deposition of the selenium dioxide also aqueous vapour is applied to the superficies of the selenium.
As one specific embodiment of our process of manufacturing selenium rectifiers, we will hereinafter describe the procedure employed in applying a selenium dioxide film overlying the selenium layer of a selenium rectifier.
The accompanying drawing shows in an exaggerated scale a side elevation of a selenium rectifier produced in accordance with the rules disclosed in this invention.
A layer of selenium intimately united with a nickel-plated base member of iron in any manner well known in the art and subsequently converted into its grey crystalline state in a heat treatment is held, either manually or by the agency of a supporting device, at a given space from a source of selenium dioxide vapour. The selenium dioxide is then deposited in the form of a thin film on the free surface of the selenium; whereupon this film is coated by spraying thereon a metal forming the counter electrode of the 5 rectifier device. The so prepared rectifier cell or valve is thereafter treated inan electric formation during the course of which the formation voltage applied across-the cell or valve is gradually increased to approximately 20 volts proportional to the decreasing back current in response to the progressive improvement of the blocking layer during the formation.
This electric formation process is assumed to be the equivalency. of an electrolysis which con- 15 stitutes a selenium compound or even a layer of amorphous selenium involving the same properties as a blocking layer. I
We have discovered that the properties of, a rectified blocking layer may be still more im- 20 proved when aqueous vapour is applied to the selenium layer simultaneously with the deposition of the selenium dioxide on the free surface thereof. These two elements or constituents form a selenic acid which is easily split under the in- 2b fiuence of the electric current active during the formation process. I
The aqueous vapour may be added to the surface of the selenium layer in a variety of different manners. The simplest method which has 30 been found satisfactory in many cases comprises heating an amount of seleniumdioxide in a flame whose products of combustion include a large quantity of. aqueous vapour, and so exposing the selenium layer to the resultant gases that the 85 aqueous vapour and the vapour of selenium dioxide are simultaneously deposited on the superfices of the selenium layer. It is on the other hand likewise possible to place selenium dioxide in one receptacle and to provide a second re- 40 ceptacle containing water, either about or in the central portion of the first mentioned receptacle and to concurrently cause the contents thereof to evaporate. Still a further alternative process of imparting the necessary amount of aqueous vapour to a selenium dioxide film applied to a selenium layer overlying the base plate electrode is to store the prepared unit in a room which is maintained at a desired degree of moisture. The selenium dioxide on account of its hygroscopic nature will then absorb the required quantity of aqueous vapour proportional to the time of such storage.
The percentage of the constituents selenium dioxide and aqueous vapour to which a selenium layer is to be exposed is determined by the time during which the evaporation is eifective, by the space between the selenium layer and the receptacles containing the elements subject to evaporation and likewise by the intensity thereof. Even if the quantitative amount of evaporation might be raised in response to a temperature augment of the ambient medium, the proper relation of aqueous vapour to the selenium dioxide vapour will be maintained in each and every instant since the former is subjected to a corresponding increase.
In cases that the aqueous vapour is absorbed by the hygroscopic selenium dioxide from the moisty atmosphere in a room being maintained at a desired degree of wetness, the proper amount of vapour absorption is given by the time during which the prepared rectifier unit is stored in a room of a predetermined degree of humidity.
The period of time required for depositing the selenium dioxide with or without adding aqueous vapo'ur is equal to few seconds.
The metallic counter electrode which is preferably sprayed onto the preparatorily finished rectifier is suitably applied immediately after the selenium dioxide and the additional aqueous vapour have been deposited on the superficies of the selenium layer in order to sustain the lenium dioxide during the process as described in the foregoing.
What is claimed is:
1. The method of producing selenium rectifiers which comprises the steps of forming a layer of selenium on one major surface of a nickel-plated iron member, converting the selenium into its grey crystalline state in a heat treatment, depositing a thin film of selenium dioxide on the superficies of the layer of selenium. spraying a layer of metal onto the film of selenium dioxide overlying the selenium, and subjecting the resultant unit to an electric formation process.
2. The method of producing selenium rectifiers which comprises the steps of: forming a layer of selenium on one major surface of a nickel-plated iron member, converting the selenium into its grey crystalline state in a heat treatment, depositing a thin film of selenium dioxide on the superficies of the layer of selenium while simultaneously adding aqueous vapour to the selenium dioxide, immediately spraying a layer of metal onto the film of selenium dioxide of given humidity overlying the selenium, and subjecting the resultant unit to an electric formation process.
8. The method of producing selenium rectifiers which comprises the steps of: forming a layer of selenium on one major surface of a nickelplated iron member, converting the selenium into its grey crystalline state in a heat treatment, evaporizing a quantity of selenium dioxide in a flame the combustion products of which contain a substantial percentage of aqueous vapour, exposing the grey crystalline selenium layer to the composite mixture of resulting selenium dioxide vapour and aqueous vapour for concurrently depositing the constituents of the mixture on the selenium layer in the shape of a thin film, immediately spraying a layer of metal ontothe film of selenium dioxide of given humidity overlying the selenium, and subjecting the resultant unit to an electric formation process.
4. The method of producing selenium rectlflers which comprises the steps of: forming a layer of selenium on one major surface of a nickelplated iron member, converting the selenium into its grey crystalline state in a heat treatment, depositing a thin film of selenium dioxide on the grey crystalline surface of the selenium, imparting the proper percentage of humidity to the selenium dioxide by storing during a predetermined period of time the selenium dioxide film overlying the selenium layer formed on the base member in a room maintained at a given degree of moisture, removing the unit from the storage room, immediately spraying a layer of metal onto the film of selenium dioxide of given humidity, and subjecting the resultant unit to an electric formation process.
5. As a product of manufacture, a selenium rectifier comprising a nickel-plated base member of iron acting as an electrode, a grey crystalline layer of selenium formed on the said base member, a thin film of selenium dioxide overlying said layer of selenium, and a layer of metal applied on the said film of selenium dioxide as the counter electrode of said product.
6. As a product of manufacture, a selenium rectifier comprising a nickel-plated base member of iron acting as an electrode, a grey crystalline layer of selenium formed on the said base member, a thin film of selenium dioxide of a predetermined percentage of moisture overlying said layer of selenium, and a layer of metal applied on the said film of selenium dioxide as the counter electrode of said product.
O'I'MAR GEISLER. ERICK KIPPHAN.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DES0019624 | 1938-06-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2197497A true US2197497A (en) | 1940-04-16 |
Family
ID=7475894
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US277792A Expired - Lifetime US2197497A (en) | 1938-06-07 | 1939-06-07 | Selenium rectifier and method of producing same |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US2197497A (en) |
| BE (1) | BE434337A (en) |
| CH (1) | CH214020A (en) |
| FR (1) | FR854689A (en) |
| NL (2) | NL93270C (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2433402A (en) * | 1942-07-02 | 1947-12-30 | Standard Telephones Cables Ltd | Selenium cell and lacquer therefor |
| US2452603A (en) * | 1944-04-08 | 1948-11-02 | Standard Telephones Cables Ltd | Metal contact rectifier |
| US2501798A (en) * | 1944-09-02 | 1950-03-28 | Hartford Nat Bank & Trust Co | Blocking-layer cell |
| US2507782A (en) * | 1946-02-23 | 1950-05-16 | Radio Receptor Company Inc | Rectifiers |
| US2510322A (en) * | 1945-09-22 | 1950-06-06 | Union Switch & Signal Co | Selenium rectifier |
| US2622116A (en) * | 1950-05-13 | 1952-12-16 | Edward B Gregg | Thermoelectric device |
| US2649409A (en) * | 1943-07-30 | 1953-08-18 | Standard Telephones Cables Ltd | Electrodeposition of selenium |
| US2760126A (en) * | 1953-01-30 | 1956-08-21 | Sylvania Electric Prod | Tungsten bronze rectifiers |
| DE967323C (en) * | 1943-08-06 | 1957-11-07 | Siemens Ag | Process for the production of selenium rectifiers, the top electrode of which is thallium added in small quantities |
| US2877284A (en) * | 1950-05-23 | 1959-03-10 | Rca Corp | Photovoltaic apparatus |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL66146C (en) * | 1944-08-08 | 1900-01-01 |
-
0
- BE BE434337D patent/BE434337A/xx unknown
- NL NL51047D patent/NL51047C/xx active
- NL NL93270D patent/NL93270C/xx active
-
1939
- 1939-05-01 CH CH214020D patent/CH214020A/en unknown
- 1939-05-12 FR FR854689D patent/FR854689A/en not_active Expired
- 1939-06-07 US US277792A patent/US2197497A/en not_active Expired - Lifetime
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2433402A (en) * | 1942-07-02 | 1947-12-30 | Standard Telephones Cables Ltd | Selenium cell and lacquer therefor |
| US2649409A (en) * | 1943-07-30 | 1953-08-18 | Standard Telephones Cables Ltd | Electrodeposition of selenium |
| DE967323C (en) * | 1943-08-06 | 1957-11-07 | Siemens Ag | Process for the production of selenium rectifiers, the top electrode of which is thallium added in small quantities |
| US2452603A (en) * | 1944-04-08 | 1948-11-02 | Standard Telephones Cables Ltd | Metal contact rectifier |
| US2501798A (en) * | 1944-09-02 | 1950-03-28 | Hartford Nat Bank & Trust Co | Blocking-layer cell |
| US2510322A (en) * | 1945-09-22 | 1950-06-06 | Union Switch & Signal Co | Selenium rectifier |
| US2507782A (en) * | 1946-02-23 | 1950-05-16 | Radio Receptor Company Inc | Rectifiers |
| US2622116A (en) * | 1950-05-13 | 1952-12-16 | Edward B Gregg | Thermoelectric device |
| US2877284A (en) * | 1950-05-23 | 1959-03-10 | Rca Corp | Photovoltaic apparatus |
| US2760126A (en) * | 1953-01-30 | 1956-08-21 | Sylvania Electric Prod | Tungsten bronze rectifiers |
Also Published As
| Publication number | Publication date |
|---|---|
| CH214020A (en) | 1941-03-31 |
| NL51047C (en) | |
| FR854689A (en) | 1940-04-22 |
| BE434337A (en) | |
| NL93270C (en) |
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