US2614052A - Manufacture of copper oxide rectifiers - Google Patents

Manufacture of copper oxide rectifiers Download PDF

Info

Publication number
US2614052A
US2614052A US81838A US8183849A US2614052A US 2614052 A US2614052 A US 2614052A US 81838 A US81838 A US 81838A US 8183849 A US8183849 A US 8183849A US 2614052 A US2614052 A US 2614052A
Authority
US
United States
Prior art keywords
blanks
rectifiers
copper
copper oxide
dipping
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
Application number
US81838A
Inventor
Herbert L Taylor
Linnie K Hedding
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Westinghouse Air Brake Co
Original Assignee
Westinghouse Air Brake Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Westinghouse Air Brake Co filed Critical Westinghouse Air Brake Co
Priority to US81838A priority Critical patent/US2614052A/en
Priority to GB4977/50A priority patent/GB674440A/en
Application granted granted Critical
Publication of US2614052A publication Critical patent/US2614052A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture 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
    • H01L21/16Manufacture 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 cuprous oxide or cuprous iodide
    • H01L21/161Preparation of the foundation plate, preliminary treatment oxidation of the foundation plate, reduction treatment
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104Forming layers
    • H01L21/02365Forming inorganic semiconducting materials on a substrate
    • H01L21/02518Deposited layers
    • H01L21/02521Materials
    • H01L21/02565Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104Forming layers
    • H01L21/02365Forming inorganic semiconducting materials on a substrate
    • H01L21/02612Formation types
    • H01L21/02614Transformation of metal, e.g. oxidation, nitridation

Definitions

  • Our invention relates to the manufacture of copper oxide rectifiers, and particularly to .a method of preparing copper blanks for oxidation to produce such rectifiers.
  • the rectifying ratio may be defined as the ratio between the forward resistance measured under specified conditions and the reverse resistance, usually measured under different specified conditions.
  • the forward resistance stability is concerned with the variations in the forward resistance of the rectifier over a period of time, usually a year or more, following its manufacture.
  • the reverse resistance stability is similar.
  • the term forward resistance is used to describe the resistance of the rectifier to current flow in the low resistance direction and the term reverse resistance is used to describe the resistance of the rectifier to current flow in the high resistance direction.
  • rectifiers produced by the same process from different samples of copper vary widely in respect to these three characteristics.
  • the cause of this variation is not known, but it is commonly attributed to the presence in the copper of minute quantities of impurities whose exact nature has not been determined.
  • the quality of rectifiers varies with the source of the copper, that is, copper from one mine will consistently produce good rectifiers, whereas copper from a different mine will consistently produce poor rectifiers.
  • the blanks in a dilute water solution of hydriodic acid. We have found that a concentration of from 1.8 to 3.6 parts hydrogen iodide per million parts of solution produces a satisfactory result.
  • the length of the dipping is not critical, but we have found that good results are obtained by dipping the blanks in the acid solution for at least thirty seconds. When the blanks are removed from the dipping solution, they are shaken to remove excess solution and are then dried in an air blast.
  • the blanks are oxidized at a temperature in the neighborhood of 1030 C. for approximately 13 minutes, and are then cooled in air to a temperature in the neighborhood of 550 C. Then they are annealed for approximately 10 minutes at substantially the latter temperature, after which they are quenched in running tap water to produce the finished rectifiers.
  • the process steps just described, after the dipping and drying steps, are Well known in the art.
  • a method of manufacturing copper oxide rectifiers from copper blanks comprising the steps of dipping the blanks in a hydriodic acid solution having a concentration of approximately 1.8 to 3.6 parts hydrogen iodide per million parts of water, drying the blanks, and then oxidizing the blanks.
  • a method of manufacturing copper oxide rectifiers from copper blanks comprising the steps of dipping the blanks in a-hydriodic acid solution having a concentration of approximately 1.8 to 3.6 parts hydrogen iodide per million parts of water for a period of at least 30 seconds, drying the blanks, and then oxidizing the blanks.
  • a method of manufacturing copper oxide rectifiers from copper blanks comprising the steps of cleaning the blanks to remove surface impurities, dipping the blanks in a Water solution of 'hydl'iOdiC acid having a concentration of from 1.8 to 3.6 parts hydrogen iodide per million; drying the blanks; oxidizing the blanks ata temperature in the neighborhood of 1030 C. for
  • a method of manufacturing copper oxide rectifiers from copper blanks comprising the steps of cleaning the blanks to remove surface impurities; dipping the blanks in a water solution of hydriodic acid having a concentration of from 1.8 to 3.6 parts hydrogen iodide per million; drying the blanks; and then oxidizing the blanks.

Landscapes

  • Engineering & Computer Science (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)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
  • Apparatuses And Processes For Manufacturing Resistors (AREA)

Description

Patented Oct. 14, 1952 MANUFACTURE OF COPPER OXIDE RECTIFIERS Herbert L. Taylor, Turtle Creek, and Linnie K. Hedding, Wilkinsburg, Pa., assignors to Westinghouse Air Brake Company, a corporation of Pennsylvania No Drawing.
4 Claims.
1 Our invention relates to the manufacture of copper oxide rectifiers, and particularly to .a method of preparing copper blanks for oxidation to produce such rectifiers.
There are three principal characteristics by which the performance of copper oxide rectifiers is judged. These are the rectifying ratio, the forward resistance stability, and the reverse resistance stability. The rectifying ratio may be defined as the ratio between the forward resistance measured under specified conditions and the reverse resistance, usually measured under different specified conditions. The forward resistance stability is concerned with the variations in the forward resistance of the rectifier over a period of time, usually a year or more, following its manufacture. The reverse resistance stability is similar. The term forward resistance is used to describe the resistance of the rectifier to current flow in the low resistance direction and the term reverse resistance is used to describe the resistance of the rectifier to current flow in the high resistance direction.
It is well known that rectifiers produced by the same process from different samples of copper vary widely in respect to these three characteristics. The cause of this variation is not known, but it is commonly attributed to the presence in the copper of minute quantities of impurities whose exact nature has not been determined. It is known that the quality of rectifiers varies with the source of the copper, that is, copper from one mine will consistently produce good rectifiers, whereas copper from a different mine will consistently produce poor rectifiers.
It is also known that copper from the beginning of the pour from the smelter will produce better rectifiers than copper from the end of the pour.
It is an object of the present invention to provide a process of manufacturing rectifiers whereby the performance characteristics of the rectifiers may be improved.
We shall describe a process embodying our invention, and shall then point out the novel features thereof in claims.
In the practice of our invention, We take copper blanks and clean them in any suitable manner. For example, they may be cleaned in a solution of 50% normal nitric acid. The blanks are then treated to remove all traces of the cleaning reagent, preferably by rinsing them in distilled water. These cleaning and rinsing steps are old in the art.
We then perform the step which embodies our present invention, and which consists in dipping ApplicationMarch 16, 1949, Serial No. 81,838
the blanks in a dilute water solution of hydriodic acid. We have found that a concentration of from 1.8 to 3.6 parts hydrogen iodide per million parts of solution produces a satisfactory result. The length of the dipping is not critical, but we have found that good results are obtained by dipping the blanks in the acid solution for at least thirty seconds. When the blanks are removed from the dipping solution, they are shaken to remove excess solution and are then dried in an air blast.
Immediately after the dipping and drying steps, we proceed to oxidize the blanks. In a typical process, the blanks are oxidized at a temperature in the neighborhood of 1030 C. for approximately 13 minutes, and are then cooled in air to a temperature in the neighborhood of 550 C. Then they are annealed for approximately 10 minutes at substantially the latter temperature, after which they are quenched in running tap water to produce the finished rectifiers. The process steps just described, after the dipping and drying steps, are Well known in the art.
We have found from tests that rectifiers produced in accordance with the process described above have an improved rectifying ratio. This improvement is especially noticeable on rectifiers produced from end of pour copper. This improvement in the rectifying ratio results from an increase in the forward resistance and a disproportionately greater increase in the reverse resistance. We have also found that the process improves the forward resistance stability. It has little or no effect on the reverse resistance stability. In those tests where a change in the reverse resistance stability was found, that stability was improved.
As a result of the increased resistance characteristics and the increased rectifying ratio, it
has been possible to increase the voltage rating of rectifiers produced in accordance with this process by as much as 50% over the voltage rating of rectifiers produced from the same copper by previous processes.
We have found that the improved results described above are especially noticeable in tests conducted at high temperatures, in the neighborhood of C.
Although we have herein shown and described only one process embodying our invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of our invention.
Having thus described our invention, What We claim is:
1. A method of manufacturing copper oxide rectifiers from copper blanks comprising the steps of dipping the blanks in a hydriodic acid solution having a concentration of approximately 1.8 to 3.6 parts hydrogen iodide per million parts of water, drying the blanks, and then oxidizing the blanks.
2. A method of manufacturing copper oxide rectifiers from copper blanks comprising the steps of dipping the blanks in a-hydriodic acid solution having a concentration of approximately 1.8 to 3.6 parts hydrogen iodide per million parts of water for a period of at least 30 seconds, drying the blanks, and then oxidizing the blanks.
3. A method of manufacturing copper oxide rectifiers from copper blanks comprising the steps of cleaning the blanks to remove surface impurities, dipping the blanks in a Water solution of 'hydl'iOdiC acid having a concentration of from 1.8 to 3.6 parts hydrogen iodide per million; drying the blanks; oxidizing the blanks ata temperature in the neighborhood of 1030 C. for
approximately 13 minutes; cooling the oxidized blanks in air to a temperature in the neighborhood of 550 0.; annealing the oxidized blanks for approximately 10 minutes at the latter temperature; and quenching the oxidized blanks in running tap water to form finished rectifiers.
4. A method of manufacturing copper oxide rectifiers from copper blanks comprising the steps of cleaning the blanks to remove surface impurities; dipping the blanks in a water solution of hydriodic acid having a concentration of from 1.8 to 3.6 parts hydrogen iodide per million; drying the blanks; and then oxidizing the blanks.
HERBERT L. TAYLOR. LINNIE K. HEDDING.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,834,275 Geiger Dec. 1, 1931

Claims (1)

  1. 4. A METHOD OF MANUFACTURING COPPER OXIDE RECTIFIERS FROM COPPER BLANKS COMPRISING THE STEPS OF CLEANING THE BLANKS TO REMOVE SURFACE IMPURITIES; DIPPING THE BLANKS IN A WATER SOLUTION OF HYDRIODIC ACID HAVING A CONCENTRATION OF FROM 1.8 TO 3.6 PARTS HYDROGEN IODIDE PER MILLION; DRYING THE BLANKS; AND THEN OXIDIZING THE BLANKS.
US81838A 1949-03-16 1949-03-16 Manufacture of copper oxide rectifiers Expired - Lifetime US2614052A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US81838A US2614052A (en) 1949-03-16 1949-03-16 Manufacture of copper oxide rectifiers
GB4977/50A GB674440A (en) 1949-03-16 1950-02-27 Improvements relating to the manufacture of copper oxide rectifiers

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US81838A US2614052A (en) 1949-03-16 1949-03-16 Manufacture of copper oxide rectifiers

Publications (1)

Publication Number Publication Date
US2614052A true US2614052A (en) 1952-10-14

Family

ID=22166716

Family Applications (1)

Application Number Title Priority Date Filing Date
US81838A Expired - Lifetime US2614052A (en) 1949-03-16 1949-03-16 Manufacture of copper oxide rectifiers

Country Status (2)

Country Link
US (1) US2614052A (en)
GB (1) GB674440A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2938716A (en) * 1956-05-28 1960-05-31 Harold B Conant Apparatus for producing copper oxide cells
US2960757A (en) * 1956-05-21 1960-11-22 Texas Instruments Inc Method of making electrical heating assembly

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1834275A (en) * 1929-10-09 1931-12-01 Union Switch & Signal Co Manufacture of copper oxide rectifiers

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1834275A (en) * 1929-10-09 1931-12-01 Union Switch & Signal Co Manufacture of copper oxide rectifiers

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2960757A (en) * 1956-05-21 1960-11-22 Texas Instruments Inc Method of making electrical heating assembly
US2938716A (en) * 1956-05-28 1960-05-31 Harold B Conant Apparatus for producing copper oxide cells

Also Published As

Publication number Publication date
GB674440A (en) 1952-06-25

Similar Documents

Publication Publication Date Title
US2375355A (en) Selenium rectifier
US2614052A (en) Manufacture of copper oxide rectifiers
US2766509A (en) Titanium dioxide rectifier
US2461228A (en) Donald lee miles
US2224573A (en) Alloy
US2592975A (en) Method of grading copper for use in
US2320962A (en) Treatment of copper-oxide rectifiers with nitrogen
US2158748A (en) Manufacture of electrical rectifiers
US2201709A (en) Manufacture of alternating electric current rectifiers
SE427117B (en) SEE ON GLOWING OF COLD ROLLED ELECTROMAGNETIC SILICONE WHERE STALET SURFACE IS COVERED WITH ELDFIXED OXID MATERIAL
US2186781A (en) Electrical rectifier
US3532591A (en) Etching silicide coatings and article formed therefrom
US1936792A (en) Method of making copper oxide rectifiers for high voltage application
US1926132A (en) Manufacture of electrical rectifiers
US2205263A (en) Copper oxide rectifier
US2471898A (en) Reclamation of selenium rectifier cells
US1834275A (en) Manufacture of copper oxide rectifiers
US2213389A (en) Manufacture of electrical rectifiers
US2531535A (en) Manufacture of alternating electric current rectifiers
US2508161A (en) Rectifier element
US2253533A (en) Electric make and break contact
US2459630A (en) Rectifier
US2128054A (en) Method of working alloys
US2793968A (en) Method of making copper oxide rectifier cells
US2172576A (en) Manufacture of alternating elec