US3847758A - Method of manufacturing an electrode system - Google Patents

Method of manufacturing an electrode system Download PDF

Info

Publication number
US3847758A
US3847758A US00331993A US33199373A US3847758A US 3847758 A US3847758 A US 3847758A US 00331993 A US00331993 A US 00331993A US 33199373 A US33199373 A US 33199373A US 3847758 A US3847758 A US 3847758A
Authority
US
United States
Prior art keywords
grains
layer
insulating material
cores
parts
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
US00331993A
Inventor
Velde T Te
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.)
US Philips Corp
Original Assignee
US Philips Corp
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 US Philips Corp filed Critical US Philips Corp
Application granted granted Critical
Publication of US3847758A publication Critical patent/US3847758A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/0248Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
    • H01L31/036Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by their crystalline structure or particular orientation of the crystalline planes
    • H01L31/0384Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by their crystalline structure or particular orientation of the crystalline planes including other non-monocrystalline materials, e.g. semiconductor particles embedded in an insulating material
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • YGENERAL 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
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S148/00Metal treatment
    • Y10S148/12Photocathodes-Cs coated and solar cell

Definitions

  • ABSTRACT [30] Foreign Application Priority Data
  • the invention relates to a method of manufacturing an Feb 19, Netherlands ele trode ystem having a monogram layer On free 7 grain surfaces of the monograin layer a first electrode U-S. s R, layer is d posited a material removing treat- 29/572 ment, a deposition step is applied in which parts of en- 5/48, C23b 11/00, 301k 5/02 veloping layers of the grains and edges of cores of the [58] Field of Search. 29/572; 204/181, 56 R,
  • the invention relates to a method of manufacturing an electrode system having a monograin layer, in which grains of a semiconductor material with enveloping layers and cores of opposite conductivity types are embedded in a layer of binder in a substantially monograin layer over a part of the layer thickness, a first electrode layer for contacting the enveloping layers of the grains is deposited on one side of the monograin layer with free grain surfaces, a material-removing treatment is used in which parts of the cores of the grains and parts of the enveloping layers of the grains are exposed, after which in
  • the invention furthermore relates to an electrode system manufactured by means of the method.
  • the said electrode systems may comprise monograin layers with grains operating as diodes, in which the first and the second electrode layer are deposited on oppositely located sides of the monograin layer.
  • Electrodes systems manufactured by means of the above-mentioned method is often free from electrode layers to facilitate the entrance and/or emanation of light.
  • These electrode systems ar used, for example, in solar cells and in injection luminescent light sources.
  • the enveloping layers of the grains must be connected together and the cores of the grains must be connected together by electrode layers which may not contact each other.
  • an insulating layer is provided on the first electrode layer and the material-removing treatment is applied on the side of said layers and the material of the grains and the material of the first insulating layer must be matched to each other in such manner and the material-removing treatment should be such that of the grains a part of the first electrode layer and a part of the enveloping layer of the grains is removed and between the grains the first insulating layer is removed over a greater part of the layer thickness without, however, entirely removing the first electrode layer from and between the grains.
  • a second material-removing treatment is carried out in which the material of the grain and the material of the second insulating layer are to be removed to an equal extent so as to be able to deposit the second electrode layer which contacts the cores of the grains and is separated from the first electrode layer.
  • the materials of the two insulating layers and of the grains must be accurately matched to each other and in addition very high requirements are imposed upon the material-removing treatment so that the abovedescribed method is difficult and cumbersome and often does not produce the desired result but results, for example, in shortcircuit.
  • One of the objects of the invention is to provide a novel method of contacting the cores of the grains and the enveloping layers of the grainsin an insulated manner and furthermore to provide an improvement of the method described in the US. patent specification, as a result of which the manufacture becomes easier and can be carried out in fewer steps.
  • the invention is inter alia based on the recognition of the fact that the second material-removing treatment may be omitted when no more insulating material is used than is necessary for the insulation of the second electrode layer relative to the enveloping layers of grains.
  • the method is characterized in that in said process step the insulating material is selectively provided on the exposed parts of the enveloping layers of the grains and on edges of the exposed parts of the cores of the grains adjoining the junctions and parts of the cores of the grains not covered during the provision of the insulating material are then contacted by depositing the second electrode layer.
  • a second material-removing treatment may be omitted and it is achieved that the material-removing treatment to be used can be particularly simple since no relief need be provided in the monograin layer.
  • Agrinding or polishing process is preferably chosen as the materialremoving treatment.
  • An insulating layer is preferably provided on the first electrode layer and the material-removing treatment is applied to both last-mentioned layers, parts of the first electrode layer being exposed, said last-mentioned parts being covered during the selective provision of the insulating material.
  • the insulating material is provided by electrophoresis in that the exposed parts are contacted with a bath containing an insulating material suitable for electrophoretic coating and electrophoresis is carried out by giving the first electrode layer a voltage relative to the bath at which the junctions between the cores of the grains and the enveloping layers of the grains are biased in the reverse direction.
  • the insulating material is provided by electrochemical polymerization in that the'exposed parts are contacted with a bath containing a material which is converted into the insulating material by electrochemicalpolymerization and polymerization is carried by giving the first electrode layer a voltage relative to the bath at which the junctions between the cores of the grains and the enveloping layers of the grains are biased in the reverse direction.
  • the provision of the insulating material proceeds more slowly according as more material is provided and is finally discontinued automatically.
  • the insulating material is preferably provided on the monograin layer prior to the material-removing treatment and after the treatment the insulating material is caused to swell so that the exposed parts of the enveloping layers of the grains and the edges of the exposed parts of the cores of the grains adjoining the junctions are covered.
  • Swelling may be carried out, for example, by a treatment with vapour or a solution with a swelling agent suitable for the insulating material.
  • the swelling agent may be removed, for example, by evaporation or extraction, in which insulating material remains in the place covered due to the swelling.
  • the monograin layer is preferably obtained prior to depositing the first electrode layer in that the grains are provided as a substantially monograin layer in an adhesive layer on a substantially plane substrate and embedded in the layer of binder, after which the monograin layer is separated from the substrate to obtain the side with the free grain surfaces.
  • the side with the free grain surfaces is then treated with a specific solvent for the binder so as to enlarge the free grain surface.
  • the invention furthermore relates to an electrode system manufactured by means of the method according to the invention.
  • FIGS. 1 to 5 are diagrammatic sectional views of parts of an electrode system in successive stages of manufacture by means of preferred embodiments of the method according to the invention and
  • FIG. 6 is a diagrammatic sectional view of a part of an electrode system in a stage of manufacture by means ofa variation of the method according to the invention.
  • An electrode system 51 (see FIG. 5) with a monograin layer (11, 21) is manufactured, in which grains 11 having a size of approximately 50 um and consisting of semiconductor material, for example gallium phosphide, having approximately 5 pm thick enveloping layers 12 and cores 13 of opposite conductivity types are embedded in a layer 21 of binder (see FIG. 3) in a substantially monograin layer over part of the layer thickness.
  • semiconductor material for example gallium phosphide
  • a first electrode layer 41 for contacting the enveloping layers of. the grains is deposited on one side 31 of the monograin layer (11, 21) with free grain surfaces, for example, by means of vapour deposition of gold.
  • An insulating layer 42 for example of polyurethane, is provided on the first electrode layer 41.
  • Insulating material 52 of materials to be described hereinafter is selectively provided in the form of a pattern of grains on the exposed parts 44 of the enveloping layers 12 of the grains, on the exposed parts 45 of the first electrode layer 41 and on edges 54 of the exposed parts 43 of the cores 13 of the grains adjoining the junctions 14.
  • Parts of the cores 13 of the grains not covered during the provision of the insulating material 52 are then contacted by depositing the second electrode layer 53.
  • ions are implanted in a usual manner in the gallium phosphide grains of an element which can cause the same conductivity type in the gallium phosphide as the cores of the grain have, and a second electrode layer 53 is deposited, for example, by vapourdepositing gold.
  • the first electrode layer 41 and the second electrode layer 53 can be provided with current conductors in a usual manner.
  • the monograin layer (11, 21) is obtained prior to depositing the first electrode layer 41 by providing the grains 11 as a layer which has a thickness substantially of one grain in an adhesive layer 15 on a substantially plane substrate 6 (see FIG. 1).
  • the adhesive layer 15 consists, for example, of a usual rubber glue and the substrate 16 of glass.
  • the grains 11 are embedded in the layer 21 of binder (see FIG. 2) which consists of an electrically insulating material, for example, polyurethane.
  • the monograin layer (11, 21) is then separated from the substrate 16 and the side 31 with the free grain surfaces is obtained (see FIG. 3).
  • the free grain surface may still be enlarged by a treatment with a specific solvent for a binder.
  • a treatment with an alcoholic potassium hydroxide solution in the case of polyurethane this can be carried out in a usual manner by a treatment with an alcoholic potassium hydroxide solution.
  • EXAMPLE 1 In the first example the insulating material 52 is provided by electrophoresis in that the exposed parts 43, 44, 45 are contacted with a bath containing an insulating material suitable for electrophoretic coating.
  • Electrophoresis is carried out by giving the first electrode layer 41 a voltage relative to the bath at which the junctions 14 between the cores 13 of the grains and the enveloping layers 12 of the grains are biased in the reverse direction.
  • the grains consist, for example, of the semiconductor material gallium phosphide.
  • the cores 13 By doping with zinc the cores 13 have been made p-type conductive and by doping with sulfur the enveloping layers 12 have been made n-type conductive.
  • a bath is used of a solution of a synthetic resin containing carboxyl groups and/0r hydroxyl groups and of an organic amine or ammonia in water.
  • the weight concentration of solid of the solution is ID to l5 percent.
  • Conventional materials such as epoxy-, acrylateor alkyl resins maybe used as a synthetic resin.
  • a positive voltage of, for example, approximately +100 volt relative to the bath is given to the first electrode layer 41.
  • the current rapidly decreases to a fraction, for example, 1 to percent of the original value, and the exposed parts 44, 45 and at most edges 54 of the exposed parts 43 of the cores 13 of the grains are covered.
  • the insulating material reaches, for example, a layer thickness of 5 um.
  • the insulating material is finally subjected to a baking treatment for 5 to minutes 120 to 180C.
  • a certain current density is adjusted (in the order of magnitude of 0.1 mA/cm and the process is discontinued when the voltage has reached a certain high value.
  • EXAMPLE 2 differs from the first example in that in this case the insulating material 53 is provided by electrochemical polymerisation in that the exposed parts 43, 44, 45 are contacted with a bath containing a material which is converted into the insulating material by electrochemical polymerisation.
  • the polymerisation is carried out by giving the first electrode layer 41 a voltage relative to the bath at which the junctions 14 between the cores 13 of the grains and the enveloping layers 12 of thegrains are biased in the reverse direction.
  • a bath having a mixture of orthoisopropylphenol and triethylamine in a molecular ratio of 10 1.
  • insulating material 52 is provided in a'thickness of 0.6 am. The current density decreases during the process from approximately 10' A/cm to approximately 10' A/cm":
  • the third example differs from the preceding examples in that the insulating material is provided on the monograin layer (11, 21) prior to the materialremoving treatment and the insulating material after the treatment is allowed to swell so that the exposed parts 45 of the first electrode layer 41, the exposed parts 44 of the enveloping layers 12 of the grains and the edges 54 of the exposed parts 43 of the cores 13 of the grains adjoining the junctions 14 are covered (see FIG. 6).
  • Theinsulating material is provided, for example, as an insulating layer 42.
  • As a material for the insulating layer 42 is used, for example, polyurethane which swells by a treatment with vapour of ethyl acetate.
  • insulating-material52 After removing the ethyl acetate by evaporation at 80C, insulating-material52 remains in the places covered by the swelling.
  • gallium phosphide another suitable semiconductor material, for example zinc selenide, mixed crystals of gallium arsenide and-gallium phosphide or mixedcrystalsof gallium arsenide and aluminium arsenidemay be used.
  • the cores of the grains may also show n-type conductivity and the enveloping layers of the grains may show p-type conductivity.
  • the insulating material used in the electrophoretic coating and the material used in the electrochemical polymerisation must be adapted to the polarity of the first electrode layer varyingrelative to the bath.
  • electrophoretic coating for example, synthetic resins on the basis of melamine are to be considered.
  • the method according to the invention may also be used in manufacturing electrode systems in which the electrode layers are present on oppositely located sides of the monograin layer.
  • a method of manufacturing an electrode system having a monograinlayer in which grains of a semiconductor material with enveloping layers and cores of opposite conductivity types are embedded in a layer of binder in a substantially monograin layer over a part of the layer thickness, a first electrode layer for contacting the enveloping layers of the grains is deposited on one side of the monograin layer with free grain surfaces, a material-removing treatment is used in which parts of the cores of the grains and parts of the enveloping layers of the grains are exposed, after which in a succeeding process step insulating material is provided on the exposed partsand a second electrode layer for contacting the cores of the grains is deposited, characterized in that in said process step the insulating material is selectively provided on the exposed parts of the enveloping layers of the grains and on edges of the exposed parts of the cores of the grains adjoining the junctions and parts of thecores of the grains not covered during the provision of the insulating material are then contacted by depositing the second electrode layer.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Computer Hardware Design (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Physics & Mathematics (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Led Devices (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Light Receiving Elements (AREA)
  • Photovoltaic Devices (AREA)
  • Printers Or Recording Devices Using Electromagnetic And Radiation Means (AREA)

Abstract

The invention relates to a method of manufacturing an electrode system having a monograin layer. On free grain surfaces of the monograin layer a first electrode layer is deposited. After a material-removing treatment, a deposition step is applied in which parts of enveloping layers of the grains and edges of cores of the grains adjoining pn-junctions are selectively covered with an insulating material and a second eletrode layer is deposited on parts of the cores of the grains not covered.

Description

[56] References Cited United States Patent I [111 3,847,758 Te Velde [451 Nov. 12,1974
[ METHOD OF MANUFACTURING AN 3,040,416 6/1962 ELECTRODE SYSTEM 3.038.952 6/1962 2,904,6l3 9/l959 [75] Inventor: Ties Siebolt Te Velde, Emmasingel,
Eindhoven, Netherlands Primary Examiner-John H. Mack [73] Asslgnee' gb g g Corporanon New Assistant ExaminerR. L. Andrews Attorney, Agent, or Firnz-Frank R. Trifari [22] Filed: Feb. 12, 1973 [2l] Appl. No.: 331,993
[57] ABSTRACT [30] Foreign Application Priority Data The invention relates to a method of manufacturing an Feb 19, Netherlands ele trode ystem having a monogram layer On free 7 grain surfaces of the monograin layer a first electrode U-S. s R, layer is d posited a material removing treat- 29/572 ment, a deposition step is applied in which parts of en- 5/48, C23b 11/00, 301k 5/02 veloping layers of the grains and edges of cores of the [58] Field of Search. 29/572; 204/181, 56 R,
204/15 with an insulating material and a second eletrode layer is deposited on parts of the cores of the grains not covered. UNITED STATES PATENTS 3,575,823 4/1971 Gordon 204/15 8 Claims, 6 Drawing Figures grains adjoining pn-junctions are selectively covered PATENTEL nnv 1 2 I974 SHEEI 10F 2 METHOD OF MANUFACTURING AN ELECTRODE SYSTEM The invention relates to a method of manufacturing an electrode system having a monograin layer, in which grains of a semiconductor material with enveloping layers and cores of opposite conductivity types are embedded in a layer of binder in a substantially monograin layer over a part of the layer thickness, a first electrode layer for contacting the enveloping layers of the grains is deposited on one side of the monograin layer with free grain surfaces, a material-removing treatment is used in which parts of the cores of the grains and parts of the enveloping layers of the grains are exposed, after which in a succeeding process step insulating material is provided on the exposed part and a second electrode layer for contacting the cores of the grains is deposited.
The invention furthermore relates to an electrode system manufactured by means of the method.
The said electrode systems may comprise monograin layers with grains operating as diodes, in which the first and the second electrode layer are deposited on oppositely located sides of the monograin layer.
One side of other electrode systems manufactured by means of the above-mentioned method is often free from electrode layers to facilitate the entrance and/or emanation of light. These electrode systems ar used, for example, in solar cells and in injection luminescent light sources.
In manufacturing the said electrode systems, the enveloping layers of the grains must be connected together and the cores of the grains must be connected together by electrode layers which may not contact each other.
It is often difficult to fulfil this requirement since in the material-removing treatment both the cores of the grains and the enveloping layers of the grains are exposed; this holds good in particular if one of the sides of the electrode system must be free from contact layers. For example, in a method of the type mentioned in the preamble (see US. Pat. No. 3,040,416) an insulating layer is provided on the first electrode layer and the material-removing treatment is applied on the side of said layers and the material of the grains and the material of the first insulating layer must be matched to each other in such manner and the material-removing treatment should be such that of the grains a part of the first electrode layer and a part of the enveloping layer of the grains is removed and between the grains the first insulating layer is removed over a greater part of the layer thickness without, however, entirely removing the first electrode layer from and between the grains.
After providing insulating material in the form of a second insulating layer on the exposed parts, a second material-removing treatment is carried out in which the material of the grain and the material of the second insulating layer are to be removed to an equal extent so as to be able to deposit the second electrode layer which contacts the cores of the grains and is separated from the first electrode layer.
The materials of the two insulating layers and of the grains must be accurately matched to each other and in addition very high requirements are imposed upon the material-removing treatment so that the abovedescribed method is difficult and cumbersome and often does not produce the desired result but results, for example, in shortcircuit.
One of the objects of the invention is to provide a novel method of contacting the cores of the grains and the enveloping layers of the grainsin an insulated manner and furthermore to provide an improvement of the method described in the US. patent specification, as a result of which the manufacture becomes easier and can be carried out in fewer steps. The invention is inter alia based on the recognition of the fact that the second material-removing treatment may be omitted when no more insulating material is used than is necessary for the insulation of the second electrode layer relative to the enveloping layers of grains.
Therefore, according to the invention, the method is characterized in that in said process step the insulating material is selectively provided on the exposed parts of the enveloping layers of the grains and on edges of the exposed parts of the cores of the grains adjoining the junctions and parts of the cores of the grains not covered during the provision of the insulating material are then contacted by depositing the second electrode layer.
One of the advantages obtained is that a second material-removing treatment may be omitted and it is achieved that the material-removing treatment to be used can be particularly simple since no relief need be provided in the monograin layer. Agrinding or polishing process is preferably chosen as the materialremoving treatment.
By means of the method according to the invention, good results can be obtained in providing mutually insulated electrode'layers on the cores of the grains and on the enveloping layers of the grains, for example, in manufacturing the already stated electrode system the electrode layers of which are deposited on either side of the monograin layer.
An insulating layer is preferably provided on the first electrode layer and the material-removing treatment is applied to both last-mentioned layers, parts of the first electrode layer being exposed, said last-mentioned parts being covered during the selective provision of the insulating material.
In a preferred embodiment of the method according to the invention, the insulating material is provided by electrophoresis in that the exposed parts are contacted with a bath containing an insulating material suitable for electrophoretic coating and electrophoresis is carried out by giving the first electrode layer a voltage relative to the bath at which the junctions between the cores of the grains and the enveloping layers of the grains are biased in the reverse direction.
In another preferred embodiment of the method according to the invention the insulating material is provided by electrochemical polymerization in that the'exposed parts are contacted with a bath containing a material which is converted into the insulating material by electrochemicalpolymerization and polymerization is carried by giving the first electrode layer a voltage relative to the bath at which the junctions between the cores of the grains and the enveloping layers of the grains are biased in the reverse direction.
In the above preferred embodiments, the provision of the insulating material proceeds more slowly according as more material is provided and is finally discontinued automatically.
The insulating material is preferably provided on the monograin layer prior to the material-removing treatment and after the treatment the insulating material is caused to swell so that the exposed parts of the enveloping layers of the grains and the edges of the exposed parts of the cores of the grains adjoining the junctions are covered.
Swelling may be carried out, for example, by a treatment with vapour or a solution with a swelling agent suitable for the insulating material.
The swelling agent may be removed, for example, by evaporation or extraction, in which insulating material remains in the place covered due to the swelling.
When a grinding process is used as a materialremoving treatment, it is advantageous when the grains project approximately equally far from the layer of binder with their free grain surfaces. Therefore, the monograin layer is preferably obtained prior to depositing the first electrode layer in that the grains are provided as a substantially monograin layer in an adhesive layer on a substantially plane substrate and embedded in the layer of binder, after which the monograin layer is separated from the substrate to obtain the side with the free grain surfaces.
Preferably the side with the free grain surfaces is then treated with a specific solvent for the binder so as to enlarge the free grain surface.
It is achieved that the grains project approximately equally far from the layer of binder also in the case in which all the grains are not accurately equally large.
The invention furthermore relates to an electrode system manufactured by means of the method according to the invention.
The invention will now be described in greater detail with reference to a drawing and a few examples.
In the drawing:
FIGS. 1 to 5 are diagrammatic sectional views of parts of an electrode system in successive stages of manufacture by means of preferred embodiments of the method according to the invention and FIG. 6 is a diagrammatic sectional view of a part of an electrode system in a stage of manufacture by means ofa variation of the method according to the invention.
The manufacture will now be described of an electrode system having both layers on one side of the monograin layer, which systems are used in solar cells an injection luminescent light sources. An electrode system 51 (see FIG. 5) with a monograin layer (11, 21) is manufactured, in which grains 11 having a size of approximately 50 um and consisting of semiconductor material, for example gallium phosphide, having approximately 5 pm thick enveloping layers 12 and cores 13 of opposite conductivity types are embedded in a layer 21 of binder (see FIG. 3) in a substantially monograin layer over part of the layer thickness.
After implantation in the usual manner in the gallium phosphide grain of ions of an element which can cause the same conductivity type in the gallium phosphide as the enveloping layers of the grains have, a first electrode layer 41 (see FIG. 4) for contacting the enveloping layers of. the grains is deposited on one side 31 of the monograin layer (11, 21) with free grain surfaces, for example, by means of vapour deposition of gold. An insulating layer 42, for example of polyurethane, is provided on the first electrode layer 41. By using a material-removing treatment, for which a grinding process is preferably chosen, parts 43 of the cores 13 of the grains, cores 44 of the enveloping layers 12 of the grains and parts 45 of the first electrode layer 41 are exposed.
Insulating material 52 of materials to be described hereinafter is selectively provided in the form of a pattern of grains on the exposed parts 44 of the enveloping layers 12 of the grains, on the exposed parts 45 of the first electrode layer 41 and on edges 54 of the exposed parts 43 of the cores 13 of the grains adjoining the junctions 14.
Parts of the cores 13 of the grains not covered during the provision of the insulating material 52 are then contacted by depositing the second electrode layer 53. For that purpose, ions are implanted in a usual manner in the gallium phosphide grains of an element which can cause the same conductivity type in the gallium phosphide as the cores of the grain have, and a second electrode layer 53 is deposited, for example, by vapourdepositing gold.
The first electrode layer 41 and the second electrode layer 53 can be provided with current conductors in a usual manner.
When a grinding process is used as a materialremoving treatment, it is advantageous when the grains project approximately equally far from the layer of binder with the free grain surfaces.
Therefore, the monograin layer (11, 21) is obtained prior to depositing the first electrode layer 41 by providing the grains 11 as a layer which has a thickness substantially of one grain in an adhesive layer 15 on a substantially plane substrate 6 (see FIG. 1).
The adhesive layer 15 consists, for example, of a usual rubber glue and the substrate 16 of glass. The grains 11 are embedded in the layer 21 of binder (see FIG. 2) which consists of an electrically insulating material, for example, polyurethane.
The monograin layer (11, 21) is then separated from the substrate 16 and the side 31 with the free grain surfaces is obtained (see FIG. 3).
The free grain surface may still be enlarged by a treatment with a specific solvent for a binder. in the case of polyurethane this can be carried out in a usual manner by a treatment with an alcoholic potassium hydroxide solution.
EXAMPLE 1 In the first example the insulating material 52 is provided by electrophoresis in that the exposed parts 43, 44, 45 are contacted with a bath containing an insulating material suitable for electrophoretic coating.
Electrophoresis is carried out by giving the first electrode layer 41 a voltage relative to the bath at which the junctions 14 between the cores 13 of the grains and the enveloping layers 12 of the grains are biased in the reverse direction.
The grains consist, for example, of the semiconductor material gallium phosphide. By doping with zinc the cores 13 have been made p-type conductive and by doping with sulfur the enveloping layers 12 have been made n-type conductive.
In a manner conventionally used in electrophoretic coating, a bath is used of a solution of a synthetic resin containing carboxyl groups and/0r hydroxyl groups and of an organic amine or ammonia in water. The weight concentration of solid of the solution is ID to l5 percent. Conventional materials such as epoxy-, acrylateor alkyl resins maybe used as a synthetic resin. A positive voltage of, for example, approximately +100 volt relative to the bath is given to the first electrode layer 41. During the passage of current through the bath, the current rapidly decreases to a fraction, for example, 1 to percent of the original value, and the exposed parts 44, 45 and at most edges 54 of the exposed parts 43 of the cores 13 of the grains are covered. The insulating material reaches, for example, a layer thickness of 5 um. The insulating material is finally subjected to a baking treatment for 5 to minutes 120 to 180C. During providing the insulating material there may also be proceeded so that a certain current density is adjusted (in the order of magnitude of 0.1 mA/cm and the process is discontinued when the voltage has reached a certain high value.
EXAMPLE 2 The second example differs from the first example in that in this case the insulating material 53 is provided by electrochemical polymerisation in that the exposed parts 43, 44, 45 are contacted with a bath containing a material which is converted into the insulating material by electrochemical polymerisation. The polymerisation is carried out by giving the first electrode layer 41 a voltage relative to the bath at which the junctions 14 between the cores 13 of the grains and the enveloping layers 12 of thegrains are biased in the reverse direction.
In a manner conventionally used in electrochemical polymerisation a bath is used having a mixture of orthoisopropylphenol and triethylamine in a molecular ratio of 10 1. At a positive voltage of +200 V of the first electrode layer 41 relative to the bath, insulating material 52 is provided in a'thickness of 0.6 am. The current density decreases during the process from approximately 10' A/cm to approximately 10' A/cm":
EXAMPLE 3 The third example differs from the preceding examples in that the insulating material is provided on the monograin layer (11, 21) prior to the materialremoving treatment and the insulating material after the treatment is allowed to swell so that the exposed parts 45 of the first electrode layer 41, the exposed parts 44 of the enveloping layers 12 of the grains and the edges 54 of the exposed parts 43 of the cores 13 of the grains adjoining the junctions 14 are covered (see FIG. 6). Theinsulating material is provided, for example, as an insulating layer 42. As a material for the insulating layer 42 is used, for example, polyurethane which swells by a treatment with vapour of ethyl acetate.
After removing the ethyl acetate by evaporation at 80C, insulating-material52 remains in the places covered by the swelling.
The invention is not restricted to the examples described.
For example, instead of gallium phosphide another suitable semiconductor material, for example zinc selenide, mixed crystals of gallium arsenide and-gallium phosphide or mixedcrystalsof gallium arsenide and aluminium arsenidemay be used. The cores of the grains may also show n-type conductivity and the enveloping layers of the grains may show p-type conductivity. -In the latter case, of course, the insulating material used in the electrophoretic coating and the material used in the electrochemical polymerisation must be adapted to the polarity of the first electrode layer varyingrelative to the bath. In the case of electrophoretic coating, for example, synthetic resins on the basis of melamine are to be considered. Upon providing insulating material by means of swelling it makes no difference whether the enveloping layers of the grains have p-type or ntype conductivity.
The method according to the invention may also be used in manufacturing electrode systems in which the electrode layers are present on oppositely located sides of the monograin layer.
What is claimed is:
1. A method of manufacturing an electrode system having a monograinlayer, in which grains of a semiconductor material with enveloping layers and cores of opposite conductivity types are embedded in a layer of binder in a substantially monograin layer over a part of the layer thickness, a first electrode layer for contacting the enveloping layers of the grains is deposited on one side of the monograin layer with free grain surfaces, a material-removing treatment is used in which parts of the cores of the grains and parts of the enveloping layers of the grains are exposed, after which in a succeeding process step insulating material is provided on the exposed partsand a second electrode layer for contacting the cores of the grains is deposited, characterized in that in said process step the insulating material is selectively provided on the exposed parts of the enveloping layers of the grains and on edges of the exposed parts of the cores of the grains adjoining the junctions and parts of thecores of the grains not covered during the provision of the insulating material are then contacted by depositing the second electrode layer.
2. A method as claimed in claim 1, characterized in that an insulating layer is provided on the first electrode layer, the material-removing treatment is applied to both last-mentioned layers, parts of the first electrode layer being exposed, said latter parts being covered during the selective provision of insulating material.
3. A method as claimed in claim 1, characterized in that the insulating material .is provided by electrophoresis in that the exposed parts are contacted with a bath containing an insulating material suitable for electrophoretic coating and electrophoresis is carried out by giving the first electrode layer a voltage relative to the bath at which the junctions between the cores of the grains and the enveloping layers of the grains are biased in the reverse direction.
4. A method as claimed in claim 1, characterized in that the insulating material is provided by electrochemical polymerisation in that the exposed parts are contacted with a bath containing a material which is converted into the insulating material by electrochemical polymerisation and polymerisation is carried out by giving the first electrode layera voltage relative to the bath at which the junctions between the cores of the grains and the enveloping layers of the grains are biased in the reverse direction.
5. A method as claimed in claim 1, characterized in that the insulating material is provided on the monograin layer prior to the material-removing treatment and after the treatment the insulating material is caused to swell so that the exposed parts of the enveloping laylayer on a substantially plane substrate and embedded in the layer of binder, after which the monograin layer is separated from the substrate to obtain the side with the free grain surfaces.
8. A method as claimed in claim 7, characterized in that the side with the free grain surfaces is then treated with a specific solvent for the binder so as to enlarge the free grain surface.

Claims (8)

1. A METHOD OF MANUFACTURING AN ELECTRODE SYSTEM HAVING A MONOGRAIN LAYER, IN WHICH GRAINS OF A SEMICONDUCTOR MATERIAL WITH ENVELOPING LAYERS AND CORES OF OPPOSITE CONDUCTIVITY TYPES ARE EMBEDDED IN A LAYER OF BINDER IN A SUBSTANTIALLY MONOGRAIN LAYER OVER A PART OF THE LAYER THICKNESS, A FIRST ELECTRODE LAYER FOR CONTACTING THE ENVELOPING LAYERS OF THE GRAINS IS DEPOSITED ON ONE SIDE OF THE MONOGRAIN LAYER WITH FREE GRAINS SURFACES, A MATERIAL-REMOVING TREATMENT IS USED IN WHICH PARTS OF THE CORES OF THE GRAINS AND PARTS OF THE ENVELOPING LAYERS OF THE GRAINS ARE EXPOSED AFTER WHICH IN A SUCCEEDING PROCESS STEP INSULATING MATERIAL IS PROVIDED ON THE EXPOSED PARTS AND A SECOND ELECTRODE LAYER FOR CONTACTING THE CORES OF THE GRAINS IS DEPOSITED CHARACTERIZED IN THAT IN SAID PROCESS STEP THE INSULATING MATERIAL IS SELECTIVELY PROVIDED ON THE EXPOSED PARTS OF THE ENVELOPING LAYERS OF THE GRAINS AND ON EDGES OF THE EXPOSED PARTS OF THE CORES OF THE GRAINS ADJOINING THE JUNCTIONS AND PARTS OF THE CORES OF THE GRAINS NOT COVERED DURING THE PROVISION OF THE INSULATING MATERIAL ARE THEN CONTACTED BY DEPOSITING THE SECOND ELECTRODE LAYER.
2. A method as claimed in claim 1, characterized in that an insulating layer is provided on the first electrode layer, the material-removing treatment is applied to both last-mentioned layers, parts of the first electrode layer being exposed, said latter parts being covered during the selective provision of insulating material.
3. A method as claimed in claim 1, characterized in that the insulatIng material is provided by electrophoresis in that the exposed parts are contacted with a bath containing an insulating material suitable for electrophoretic coating and electrophoresis is carried out by giving the first electrode layer a voltage relative to the bath at which the junctions between the cores of the grains and the enveloping layers of the grains are biased in the reverse direction.
4. A method as claimed in claim 1, characterized in that the insulating material is provided by electrochemical polymerisation in that the exposed parts are contacted with a bath containing a material which is converted into the insulating material by electrochemical polymerisation and polymerisation is carried out by giving the first electrode layer a voltage relative to the bath at which the junctions between the cores of the grains and the enveloping layers of the grains are biased in the reverse direction.
5. A method as claimed in claim 1, characterized in that the insulating material is provided on the monograin layer prior to the material-removing treatment and after the treatment the insulating material is caused to swell so that the exposed parts of the enveloping layers of the grains and the edges of the exposed parts of the cores of the grains adjoining the junctions are covered.
6. A method as claimed in claim 1, characterized in that a grinding process or a polishing process is chosen as a material-removing treatment.
7. A method as claimed in claim 1, characterized in that prior to depositing the first electrode layer the monograin layer is obtained in that the grains are provided as a substantially monograin layer in an adhesive layer on a substantially plane substrate and embedded in the layer of binder, after which the monograin layer is separated from the substrate to obtain the side with the free grain surfaces.
8. A method as claimed in claim 7, characterized in that the side with the free grain surfaces is then treated with a specific solvent for the binder so as to enlarge the free grain surface.
US00331993A 1972-02-19 1973-02-12 Method of manufacturing an electrode system Expired - Lifetime US3847758A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL7202215A NL7202215A (en) 1972-02-19 1972-02-19

Publications (1)

Publication Number Publication Date
US3847758A true US3847758A (en) 1974-11-12

Family

ID=19815410

Family Applications (1)

Application Number Title Priority Date Filing Date
US00331993A Expired - Lifetime US3847758A (en) 1972-02-19 1973-02-12 Method of manufacturing an electrode system

Country Status (7)

Country Link
US (1) US3847758A (en)
JP (1) JPS5117877B2 (en)
CA (1) CA978665A (en)
FR (1) FR2172359B1 (en)
GB (1) GB1421459A (en)
IT (1) IT977808B (en)
NL (1) NL7202215A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4806495A (en) * 1984-09-04 1989-02-21 Texas Instruments Incorporated Method of making solar array with aluminum foil matrix
US4917752A (en) * 1984-09-04 1990-04-17 Texas Instruments Incorporated Method of forming contacts on semiconductor members
US6762359B2 (en) * 2001-01-15 2004-07-13 Fuji Machine Mfg. Co., Ltd. Photovoltaic panel and method of producing same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4173494A (en) * 1977-02-14 1979-11-06 Jack S. Kilby Glass support light energy converter

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2904613A (en) * 1957-08-26 1959-09-15 Hoffman Electronics Corp Large area solar energy converter and method for making the same
US3038952A (en) * 1959-05-20 1962-06-12 Hoffman Electronics Corp Method of making a solar cell panel
US3040416A (en) * 1959-05-13 1962-06-26 Hoffman Electronics Corp Method of making a large area solar cell panel
US3575823A (en) * 1968-07-26 1971-04-20 Bell Telephone Labor Inc Method of making a silicon target for image storage tube

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL6813918A (en) * 1968-09-27 1970-04-01

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2904613A (en) * 1957-08-26 1959-09-15 Hoffman Electronics Corp Large area solar energy converter and method for making the same
US3040416A (en) * 1959-05-13 1962-06-26 Hoffman Electronics Corp Method of making a large area solar cell panel
US3038952A (en) * 1959-05-20 1962-06-12 Hoffman Electronics Corp Method of making a solar cell panel
US3575823A (en) * 1968-07-26 1971-04-20 Bell Telephone Labor Inc Method of making a silicon target for image storage tube

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4806495A (en) * 1984-09-04 1989-02-21 Texas Instruments Incorporated Method of making solar array with aluminum foil matrix
US4917752A (en) * 1984-09-04 1990-04-17 Texas Instruments Incorporated Method of forming contacts on semiconductor members
US6762359B2 (en) * 2001-01-15 2004-07-13 Fuji Machine Mfg. Co., Ltd. Photovoltaic panel and method of producing same

Also Published As

Publication number Publication date
NL7202215A (en) 1973-08-21
FR2172359B1 (en) 1977-12-30
GB1421459A (en) 1976-01-21
FR2172359A1 (en) 1973-09-28
CA978665A (en) 1975-11-25
JPS4896090A (en) 1973-12-08
DE2306059B2 (en) 1976-05-20
DE2306059A1 (en) 1973-08-23
JPS5117877B2 (en) 1976-06-05
IT977808B (en) 1974-09-20

Similar Documents

Publication Publication Date Title
US3290753A (en) Method of making semiconductor integrated circuit elements
US3853650A (en) Stress sensor diaphragms over recessed substrates
EP0881668A3 (en) Deposition of an electrically insulating thin film with a low dielectric constant
US3432919A (en) Method of making semiconductor diodes
US3013955A (en) Method of transistor manufacture
US3847758A (en) Method of manufacturing an electrode system
FR2357069A1 (en) PROCESS FOR MANUFACTURING CONNECTIONS ON THE LOWER AND UPPER FACES OF A GROUND PLANE LOCATED ON A SUPPORT SUBSTRATE
US3702427A (en) Electromigration resistant metallization for integrated circuits, structure and process
US3671819A (en) Metal-insulator structures and method for forming
US3522339A (en) Method of making electrical monograin layer
US3764325A (en) Method for making electrical monograin layer
JPS5775463A (en) Manufacture of semiconductor device
US2884508A (en) Thin metal films and method of making same
US3472711A (en) Charged particle detector
US3481031A (en) Method of providing at least two juxtaposed contacts on a semiconductor body
US3755092A (en) Method of introducing impurities into a layer of bandgap material in a thin-film solid state device
US8574944B2 (en) System for selectively filling pin holes, weak shunts and/or scribe lines in photovoltaic devices and photovoltaic cells made thereby
US3620832A (en) Electrode system particularly semiconductor electrode system and method of producing the same
US3796782A (en) Method of manufacturing electronic devices,in particular semiconductor devices
US3875657A (en) Dielectrically isolated semiconductor devices
EP0183948A3 (en) Process for the photochemical vapor deposition of aromatic polymers
US3702790A (en) Monolithic integrated circuit device and method of manufacturing the same
CA1176763A (en) Semiconductor device processing for readily and reliably forming electrical interconnects to contact pads
US4382977A (en) Method of producing smooth metallic layers on a substrate
US3465428A (en) Method of fabricating semiconductor devices and the like