US2349622A - Manufacture of rectifiers of the blocking layer type - Google Patents

Manufacture of rectifiers of the blocking layer type Download PDF

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US2349622A
US2349622A US423562A US42356241A US2349622A US 2349622 A US2349622 A US 2349622A US 423562 A US423562 A US 423562A US 42356241 A US42356241 A US 42356241A US 2349622 A US2349622 A US 2349622A
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Prior art keywords
selenium
blocking layer
rectifiers
manufacture
hydrogen peroxide
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Expired - Lifetime
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US423562A
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Clarence W Hewlett
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General Electric Co
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General Electric Co
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Publication date
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Priority to US423562A priority Critical patent/US2349622A/en
Priority to GB17573/42A priority patent/GB554822A/en
Priority to US516370A priority patent/US2418055A/en
Application granted granted Critical
Publication of US2349622A publication Critical patent/US2349622A/en
Priority to GB81/45A priority patent/GB621731A/en
Priority to FR947507D priority patent/FR947507A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • 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
    • H01L21/105—Treatment of the surface of the selenium or tellurium layer after having been made conductive
    • 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
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02367—Substrates
    • H01L21/0237—Materials
    • H01L21/02425—Conductive materials, e.g. metallic silicides
    • 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
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02436—Intermediate layers between substrates and deposited layers
    • H01L21/02439—Materials
    • H01L21/02491—Conductive materials
    • 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
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02518—Deposited layers
    • H01L21/02521—Materials
    • 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
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02612—Formation types
    • H01L21/02617—Deposition types
    • H01L21/02631—Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
    • 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
    • Y10S252/00—Compositions
    • Y10S252/95—Doping agent source material
    • Y10S252/951—Doping agent source material for vapor transport

Definitions

  • the present invention relates to the manufacture of alternating current rectifiers of the socalled "blocking layer type. It has a its pri; mary object the provision of a fabricating method which is adapted to produce rectifiers of good electrical properties and uniform quality.
  • the invention is directly applicable to the manufacture of rectifiers of the type which comprises a layer of solenium sandwiched between a metallic base member and a counter-electrode.
  • the rectifying properties of such a construction depend upon the existence between the selenium and the counter-electrode of a so-called "blocking layer" which has a much higher electrical resistance in one direction than in the other.
  • the present invention is concerned with an improved procedure for producing the blocking layer.
  • the selenium surface on which the blocking layer is to be produced is subjected to the action of a dilute solution of hydrogen peroxide by spraying an appropriate quantity of the peroxide solution on the selenium.
  • the hydrogen peroxide apparently has the effect of producing on the selenium a thin layer of selenium dioxide which is intimately bound to the underlying selenium and which has advantageous properties which are easily reproducible from one cell to another.
  • Fig. 1 represents an enlarged section of a fragmentary portion of a rectifier cell suitably embodying the invention
  • Fig. 2 is a schematic representation of apparatus for practising the invention
  • Fig. 3 is a plan view of a portion of the apparatus of Fig.2.
  • a metal base member (corresponding to the part l of Fig. 1) which has a shape corresponding to that desired for the finished rectifier.
  • the base memben may suitably be constituted of aluminum or of an aluminum alloy.
  • one surface of .the shaped base member is provided with a thin layer 2 of bismuth, this material having the function of assuring a better contact be- .tween the base member and a selenium layer 3 which is subsequently to be added.
  • the bismuth may be applied in one way by depositing it in vapor form in vacuum, for example, by use of the method and apparatus described in my prior U. S.'Patent 2,327,329, patented December 21, 1943.
  • selenium is deposited by vaporization on the bismuth layer, the deposition of selenium also being preferably carried out by vaporization in vacuum. It has been found advantageous in a particular case to apply the selenium in three layers, the third layer being constituted of pureselenium and the first and second layers comprising selenium which contains from .01 to .05 per cent of a halogen, preferably chlorine. (The addition of the halogen improves the conductivity of the selenium and;
  • the cell After the deposition of each of the selenium layers, the cell is subjected to heat in order further to improve its electrical characteristics.
  • a rotating table i0 having mounted on it near its periphery a plurality of disk-like rectifier cells Ii.
  • the table i0 is assumed to be slowly rotated (e. g. in a clockwise direction) by means of an electric motor or the like (not shown).
  • a vessel l3 which contains a solution H of hydrogen peroxide in distilled water.
  • This solution may suitably have a concentration between about 0.1 per cent and about 1.0 per cent, the optimum concentration being somewhat variable with different groups of cells.
  • an atomizing nozzle I! which is shown as being supported by a standard IS.
  • a compressed air nozzle H which discharges in a downward direction in proximity to the opening of the nozzle i5 causes the hydrogen peroxide solution to be discharged from the latter nozzle in the form of a downwardly directed spray.
  • a cylinder l8 supported by a drafts or other disturbing influences.
  • each of the cells H is subjected to a certain amount of the hydrogen peroxide spray as it passes under the nozzle IS.
  • the amount of spray received by any one cell is, of course, a function of the rate of discharge of the hydrogen peroxide and of the speed of rotation of the table it).
  • a hydrogen peroxide solution having a concentration of 0.3 per cent it has been found desirable in a particular case to regulate the motion of the table in such fashion that the amount of solution sprayed on the selenium surface is approximately .1 to .2 cubic millimeter per square centimeter of surface.
  • each cell may be subjected to the spray several times (e. g. from two to six times) before being removed from the rotary table and dried.
  • the treated selenium surface is covered with an appropriate counter-electrode (4 in Fig. 1).
  • a counter-electrode may be formed, for example, by spraying the surface in question with a mtal such as a soft solder applied by a Schoop gun or the like.
  • the cell is "formed” by subjecting it to a relatively prolonged passage of current in the blocking direction (i. e. with the counter-electrode at a positive potential with respect to the base member).

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  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Physics & Mathematics (AREA)
  • Power Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Food Preservation Except Freezing, Refrigeration, And Drying (AREA)
  • Formation Of Insulating Films (AREA)
  • Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)

Description

y 3, 1944. c. w. HEWLETT 2,349,622
MANUFACTURE OF RECTIFIERS OF THE BLOCKING LAYER TYPE Filed Dec. 18, 1941 lhventorz Clarence W. Hewlett,
H s Attorney.
Patented May 23, 1944 MANUFACTURE OF RECTIFIERS OF THE BLOCKING LAYER TYPE Clarence W. Hewlett, Schenectady, N. Y., assignor to General Electric Company, a corporation of New York Application December 18, 1941, Serial No. 423,562
2 Claims.
The present invention relates to the manufacture of alternating current rectifiers of the socalled "blocking layer type. It has a its pri; mary object the provision of a fabricating method which is adapted to produce rectifiers of good electrical properties and uniform quality.
The invention is directly applicable to the manufacture of rectifiers of the type which comprises a layer of solenium sandwiched between a metallic base member and a counter-electrode. The rectifying properties of such a construction depend upon the existence between the selenium and the counter-electrode of a so-called "blocking layer" which has a much higher electrical resistance in one direction than in the other. The present invention is concerned with an improved procedure for producing the blocking layer.
In accordance with the invention, the selenium surface on which the blocking layer is to be produced is subjected to the action of a dilute solution of hydrogen peroxide by spraying an appropriate quantity of the peroxide solution on the selenium. The hydrogen peroxide apparently has the effect of producing on the selenium a thin layer of selenium dioxide which is intimately bound to the underlying selenium and which has advantageous properties which are easily reproducible from one cell to another.
The aspects of the invention which I desire to protect herein are pointed out with particularity in the appended claims. The invention itself, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawing, in which Fig. 1 represents an enlarged section of a fragmentary portion of a rectifier cell suitably embodying the invention, Fig. 2 is a schematic representation of apparatus for practising the invention, and Fig. 3 is a plan view of a portion of the apparatus of Fig.2.
In fabricating rectifier cells of the type under consideration, it is expedient to start with a metal base member (corresponding to the part l of Fig. 1) which has a shape corresponding to that desired for the finished rectifier. For many purposes it is convenient to form the base memben as a relatively thin disk having a central opening for permitting a number of cells to be assembled upon a central arbor or frame. The base member may suitably be constituted of aluminum or of an aluminum alloy.
According to the preferred procedure, one surface of .the shaped base member is provided with a thin layer 2 of bismuth, this material having the function of assuring a better contact be- .tween the base member and a selenium layer 3 which is subsequently to be added. The bismuth may be applied in one way by depositing it in vapor form in vacuum, for example, by use of the method and apparatus described in my prior U. S.'Patent 2,327,329, patented December 21, 1943.
As a next step, selenium is deposited by vaporization on the bismuth layer, the deposition of selenium also being preferably carried out by vaporization in vacuum. It has been found advantageous in a particular case to apply the selenium in three layers, the third layer being constituted of pureselenium and the first and second layers comprising selenium which contains from .01 to .05 per cent of a halogen, preferably chlorine. (The addition of the halogen improves the conductivity of the selenium and;
thus decreases the operating resistance of the cell as a whole.) After the deposition of each of the selenium layers, the cell is subjected to heat in order further to improve its electrical characteristics.
After the last layer of selenium has been laid down and following the desired heat treatment of this layer, the surface of the selenium is next subjected to the action of hydrogen peroxide for the purpose of producing a blocking layer on the selenium (i. e. at 3' in Fig. 1). This may be done in one way by means of the apparatus shown in Fig. 2, in which there is shown arotating table i0 having mounted on it near its periphery a plurality of disk-like rectifier cells Ii. The table i0 is assumed to be slowly rotated (e. g. in a clockwise direction) by means of an electric motor or the like (not shown).
Above the table and in proximity to its outer edge there is supported a vessel l3 which contains a solution H of hydrogen peroxide in distilled water. This solution may suitably have a concentration between about 0.1 per cent and about 1.0 per cent, the optimum concentration being somewhat variable with different groups of cells. In order to bring the hydrogen peroxide solution into contact with the rectifier cells Ii in a suitable manner, there is provided in connection with the vessel IS an atomizing nozzle I! which is shown as being supported by a standard IS. A compressed air nozzle H which discharges in a downward direction in proximity to the opening of the nozzle i5 causes the hydrogen peroxide solution to be discharged from the latter nozzle in the form of a downwardly directed spray. A cylinder l8 supported by a drafts or other disturbing influences.
In the specified arrangement, each of the cells H is subjected to a certain amount of the hydrogen peroxide spray as it passes under the nozzle IS. The amount of spray received by any one cell is, of course, a function of the rate of discharge of the hydrogen peroxide and of the speed of rotation of the table it). When using a hydrogen peroxide solution having a concentration of 0.3 per cent, it has been found desirable in a particular case to regulate the motion of the table in such fashion that the amount of solution sprayed on the selenium surface is approximately .1 to .2 cubic millimeter per square centimeter of surface. After the hydrogen peroxide is deposited on a given cell, the continued motion ofthe table l removes the cell from the action of the spray, and the cell is thereafter allowed to dry in'air. If desired, each cell may be subjected to the spray several times (e. g. from two to six times) before being removed from the rotary table and dried.
It is believed that the action of the hydrogen peroxide is to form a layer of selenium dioxide on the selenium surface. It is probable that this selenium dioxide deposit extends to some extent into the crystal boundaries of the selenium-surface and that this accounts for the superior results obtained by this method. Regardless of what the proper explanation may be, it is a fact that cells produced in the manner specified are characterized by a very high degree of uniformity and by excellent electrical properties.
When the hydrogen peroxide treated cell is thoroughly dry, the treated selenium surface is covered with an appropriate counter-electrode (4 in Fig. 1). Such a counter-electrode may be formed, for example, by spraying the surface in question with a mtal such as a soft solder applied by a Schoop gun or the like. Finally the cell is "formed" by subjecting it to a relatively prolonged passage of current in the blocking direction (i. e. with the counter-electrode at a positive potential with respect to the base member).
The details of procedure given 'herein are, of course, exemplary rather than limiting, and I aim in the appended claims to cover all variations of the procedure which come within the true spirit and scope of the foregoing disclosure.
What I claim as new and desire to secure by Letters Patent of the United States, is:
1. In the process of fabricating a selenium rectifienthe step which comprises subjecting the surface of the selenium component of the rectiiler to the action'of a spray of an aqueous solution containing about 0.1 to 1.0 per cent of hydrogen peroxide.
2. In the process of fabricating a selenium rectifier which comprises subjecting the surface of the selenium component of the rectifier to a spray of a dilute solution of hydrogen peroxide, thereby to develop a blocking layer on the said surface, and discontinuing said treatment when about .1 to .2 cubic millimeter of said solution per square inch of surface has been deposited.
CLARENCE W. HEWLETT.
CERTIFICATE or comuzcnon. Patent No. 2,519,622. May 25, 19111;.
cmnmcs w. mm.
It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, first column, line 9, for "solenium' read selenium; and second column, line 7, for Patent 2,527 ,329' read --Patent 2,557,29--'; same column, line 19, fgr "solenium" read --se1enimn--; and that the said Letters Patent should be read with this correction therein that the same may confom to the record of the case in the Patent Office.
Signed and sealed this 25th day of July, A. D. 191111..
Leslie Frazer (Seal) Acting Commissioner of Patents.
US423562A 1941-12-18 1941-12-18 Manufacture of rectifiers of the blocking layer type Expired - Lifetime US2349622A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US423562A US2349622A (en) 1941-12-18 1941-12-18 Manufacture of rectifiers of the blocking layer type
GB17573/42A GB554822A (en) 1941-12-18 1942-12-10 Improvements in or relating to selenium rectifiers
US516370A US2418055A (en) 1941-12-18 1943-12-31 Apparatus for treating selenium rectifiers
GB81/45A GB621731A (en) 1941-12-18 1945-01-01 Improvements relating to selenium rectifier-unit treating apparatus
FR947507D FR947507A (en) 1941-12-18 1947-06-04 Manufacture of stop layer type rectifiers

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US423562A US2349622A (en) 1941-12-18 1941-12-18 Manufacture of rectifiers of the blocking layer type
US516370A US2418055A (en) 1941-12-18 1943-12-31 Apparatus for treating selenium rectifiers

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2418055A (en) * 1941-12-18 1947-03-25 Gen Electric Apparatus for treating selenium rectifiers
US2659846A (en) * 1951-05-15 1953-11-17 Int Rectifier Corp Selenium element and method of making it
US2669767A (en) * 1947-12-30 1954-02-23 Sylvania Electric Prod Selenium rectifier
US2816850A (en) * 1953-12-30 1957-12-17 Bell Telephone Labor Inc Semiconductive translator
US2912353A (en) * 1956-01-03 1959-11-10 Itt Selenium rectifier
DE1105996B (en) * 1954-04-30 1961-05-04 Siemens Ag Method and arrangement for the manufacture of selenium rectifiers
US3097308A (en) * 1959-03-09 1963-07-09 Rca Corp Semiconductor device with surface electrode producing electrostatic field and circuits therefor
US3599058A (en) * 1968-04-26 1971-08-10 Siemens Ag Selenium rectifier plate for use as an overvoltage diverter

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3688737A (en) * 1969-11-04 1972-09-05 Glass Container Mfg Inst Inc Vapor deposition apparatus including air mask
US3876410A (en) * 1969-12-24 1975-04-08 Ball Brothers Co Inc Method of applying durable lubricous coatings on glass containers
US3846155A (en) * 1972-04-17 1974-11-05 Hooker Chemical Corp Flame retardant process for cellulosics
US3958530A (en) * 1972-08-14 1976-05-25 Dart Industries Inc. Apparatus for coating an article
US3970037A (en) * 1972-12-15 1976-07-20 Ppg Industries, Inc. Coating composition vaporizer
US3989004A (en) * 1974-08-15 1976-11-02 Ball Corporation Apparatus for applying durable lubricous coatings to newly formed vitreous surfaces
US4744310A (en) * 1987-10-01 1988-05-17 Hal F. Whisnant Bale tie blanket

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1535850A (en) * 1925-04-28 o hara
US573206A (en) * 1896-12-15 Apparatus for producing ornamental su rfaces
US1132687A (en) * 1911-01-14 1915-03-23 John F Ryan Process for making waterproof materials and coatings.
FR552439A (en) * 1921-06-03 1923-05-01
US1828985A (en) * 1926-12-13 1931-10-27 Candee & Company L Method of superficially finishing rubber articles
US1847915A (en) * 1930-03-08 1932-03-01 Thermox Inc Apparatus for drying paper and the like
US1935383A (en) * 1931-01-22 1933-11-14 Rca Corp Rectifier element
US2097885A (en) * 1932-04-16 1937-11-02 Gustave E Koppe Apparatus for imparting a polish
US2188940A (en) * 1937-12-02 1940-02-06 Bell Telephone Labor Inc Electron discharge device
US2349622A (en) * 1941-12-18 1944-05-23 Gen Electric Manufacture of rectifiers of the blocking layer type

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2418055A (en) * 1941-12-18 1947-03-25 Gen Electric Apparatus for treating selenium rectifiers
US2669767A (en) * 1947-12-30 1954-02-23 Sylvania Electric Prod Selenium rectifier
US2659846A (en) * 1951-05-15 1953-11-17 Int Rectifier Corp Selenium element and method of making it
US2816850A (en) * 1953-12-30 1957-12-17 Bell Telephone Labor Inc Semiconductive translator
DE1105996B (en) * 1954-04-30 1961-05-04 Siemens Ag Method and arrangement for the manufacture of selenium rectifiers
US2912353A (en) * 1956-01-03 1959-11-10 Itt Selenium rectifier
US3097308A (en) * 1959-03-09 1963-07-09 Rca Corp Semiconductor device with surface electrode producing electrostatic field and circuits therefor
US3599058A (en) * 1968-04-26 1971-08-10 Siemens Ag Selenium rectifier plate for use as an overvoltage diverter

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Publication number Publication date
GB621731A (en) 1949-04-19
FR947507A (en) 1949-07-05
US2418055A (en) 1947-03-25
GB554822A (en) 1943-07-20

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