US3015761A - Semi-conductive electrode system - Google Patents

Semi-conductive electrode system Download PDF

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US3015761A
US3015761A US745032A US74503258A US3015761A US 3015761 A US3015761 A US 3015761A US 745032 A US745032 A US 745032A US 74503258 A US74503258 A US 74503258A US 3015761 A US3015761 A US 3015761A
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wire
semi
aluminum
aluminium
oxide layer
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US745032A
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Esselin Ludovicus Au Lambertus
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US Philips Corp
North American Philips Co Inc
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US Philips Corp
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L24/42—Wire connectors; Manufacturing methods related thereto
    • H01L24/44—Structure, shape, material or disposition of the wire connectors prior to the connecting process
    • H01L24/45—Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
    • H10D99/00—Subject matter not provided for in other groups of this subclass
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/44—Structure, shape, material or disposition of the wire connectors prior to the connecting process
    • H01L2224/45—Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
    • H01L2224/45001—Core members of the connector
    • H01L2224/45099—Material
    • H01L2224/451—Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof
    • H01L2224/45117—Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof the principal constituent melting at a temperature of greater than or equal to 400°C and less than 950°C
    • H01L2224/45124—Aluminium (Al) as principal constituent
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/44—Structure, shape, material or disposition of the wire connectors prior to the connecting process
    • H01L2224/45—Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
    • H01L2224/45001—Core members of the connector
    • H01L2224/45099—Material
    • H01L2224/451—Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof
    • H01L2224/45138—Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof the principal constituent melting at a temperature of greater than or equal to 950°C and less than 1550°C
    • H01L2224/45147—Copper (Cu) as principal constituent
    • H—ELECTRICITY
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    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
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    • H01L2924/0001—Technical content checked by a classifier
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    • H01L2924/0001—Technical content checked by a classifier
    • H01L2924/00014—Technical content checked by a classifier the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
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    • H01L2924/01—Chemical elements
    • H01L2924/01011—Sodium [Na]
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    • H01L2924/01—Chemical elements
    • H01L2924/01013—Aluminum [Al]
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    • H01L2924/01014—Silicon [Si]
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    • H01L2924/01—Chemical elements
    • H01L2924/01015—Phosphorus [P]
    • H—ELECTRICITY
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    • H01L2924/01—Chemical elements
    • H01L2924/01019—Potassium [K]
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    • H01L2924/01023—Vanadium [V]
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    • H01L2924/01—Chemical elements
    • H01L2924/01029—Copper [Cu]
    • H—ELECTRICITY
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    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01032—Germanium [Ge]
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    • H01L2924/01—Chemical elements
    • H01L2924/0105—Tin [Sn]
    • H—ELECTRICITY
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    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01074—Tungsten [W]
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    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/013—Alloys
    • H01L2924/0132—Binary Alloys
    • H01L2924/01322—Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
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    • H01L2924/013—Alloys
    • H01L2924/014—Solder alloys

Definitions

  • transistors or crystal diodes having a semi-con-v ductive body to which oneend of at least one electrode wire is secured by fusion.
  • Electrodes of aluminum are therefore manufactured by applying by fusion either pellets the electrodematerial, in the present case in the wire,
  • An object of the invention is inter alia to provide a construction in which these disadvantages do not occur,v
  • Such a wire may be manufactured by filling an aluminum tube with the other material and subsequently reducing the cross-section of the whole by swaging or expanding.
  • FIG. 1 shows diagrammatically a side-view of a diode
  • FIG. 2 shows a device for applying wires to semioonductive bodies by fusion. 7
  • FIG. 3 is a cross-sectional view of a semi-conductor device according to the invention.
  • the diode shown in FIG. 1 comprises a thin silicon disc 1 of conductivity, to which an aluminum wire 2 is secured by fusion in an oven at a temperature preferably higher than the melting point of aluminum, for instance 8009 C.
  • the oven temperature may however in principle be lower than the melting point of aluminum, but higher than the eutectic temperature of the silicon-aluminum mixture.
  • the heating takes place in reducing surroundings, for example in a mixture of nitrogen and hydrogen.
  • a small addition of hydrochloricacid gas as a flux enhances adhesion of the wire to the body.
  • the wire is provided with a genetic oxide layer 3 which ensures that the form of the wire substantially does not change during heating and that flowing-out of the aluminum is restricted within certain limits.
  • the strengthened oxide layer is naturally not present at the area wherethe aluminum must fuse togetherwith the silicon. [The reoxide sheath.
  • the thickness of the wire' is not essential According to the invention, the wireof which at least t the envelope consists of aluminum, has so thick a genetic oxide layer on its cylindrical outer surface that fusion of the aluminum is possible without breakage of the oxide layer.
  • Said oxide layer preferably has a thickness comprised between 5 and 40 microns. Consequently, this layer is much thicker than the natural oxide layer already present on aluminm and which has a thickness'of only 0.1 to 0.2 gt. 1
  • An oxide layer of sufficient thickness maybe obtained in a simple manner by chemical means or by anodic'.
  • the method according to the invention is characterized in that a wire, of which at least the envelope consists of aluminum, is provided with a genetic oxide, layer of a thickness such that fusion of the aluminum is possible without breakage of the oxide. layer, whereupon one end of this wire is secured by fusion to a semi-conductive body. It will be evident that it is also possible for short pieces to be cut from a long oxidized wire.
  • a genetic oxidelayer is to be understood to mean a layer, the aluminum content of which substantially originates from the initial wire.
  • oxide layer is to be understood to mean also layers consisting of oxide hydrates, such as the compound Al O -H O, and furthermore oxide layers strengthened by impregnation or in another way, as will be discussed more fully hereinafter.
  • the'wire homogeneously consists of aluminum.
  • a wire having an envelope of aluminum and a core of a different material may fuse together.
  • the core may consist, for example, of semi-conductive material, such as germanium or silicon. Its presence in to the invention and is usually from lOOmicrons to several millimetres in practice. a Y
  • The, semi-conductive body is means of tin solder 4.
  • the aluminum wire with its strengthened. oxide layer may be manufactured in various ways. known per se, that is to say by purely chemical means or an anodic oxidation.
  • the last-mentioned method usually gives thicker oxide layers than the first-mentioned and is therefore preferable for comparatively thick wires.
  • the wire is dipped for 4 minutes in an oxidizing bath of the conventional type containing for example,
  • the wire is then carefully rinsed and dried.
  • the thickness of the oxide layer is from 3 to 5 microns.
  • Example I Aluminum wire degreased as described in Example I is subjected at 20 C. to an anodic treatment at 60 volts (direct voltage) for one hour.
  • the bath was a conventional one, containing 50 guts. of oxalic acid C H H 2H O per litre. Also other oxidizing baths are suitable.
  • the thickness of the resultant oxide layer was about 40 microns.
  • the oxidized wire obtained in accordance with Example i or II there are cut oif pieces each having a length of mms, which in a jig of graphite are placed on the bodies of silicon (see KG. 2).
  • the jig is constituted by two parts 11 and 12, which fit into each other.
  • the part 12 has recesses 13, by which the semi-conductive bodies are kept in position, and perforations 14, by which the pieces of Wire 10 are centred with respect to the bodies.
  • the pieces of wire are found to have retained their initial form.
  • the semi-conductive bodies are after-etched in the usual manner, for example with the use of hydrofluoric .acid, the strengthened oxide-layer then again having the advantage of protecting the aluminum itself against chemical attack.
  • the pieces of Wire 10, before being applied by fusion are preferably provided with a fiat end by polishing or filing.
  • the pieces of wire 10 may be connected by" spot- Welding to a piece of cop-per Wire or copper cable which may be connected by soldering to a connecting member.
  • the strengthened oxide layer is naturally broken through, but this is not dangerous, the operation being effected at some distance from the semiconductive body.
  • FIG. 3 shows an example of such a'structure applied to a diode in an evacuated envelope.
  • the envelope comprises a base with a threaded stud 31 for attachment, and a cap 32.
  • the cap 32 contains a glass leadthrough insulator 33 containing a small metallic tube 34.
  • the aluminum wire 10 is secured by spot-Welding to a copper Wire '36 at 35.
  • the base 30 and the cap 32 are secured together by means of flanges 37 and 38, for example by Welding. Subsequently, the envelope is fully closed due to the copper wire 36 being soldered in the tube 34.
  • The-latter may contain or consist of an active impurity such as a donor and/or an acceptor, but also semi-conductive material and more
  • the silicon body 1 is soldered to the base 30,
  • An electrode comprising a wire-like ele ent adapted for fusion at one end to a semiconductive body, the outer Wire portions consisting essentially of aluminum and containing a genetic oxide layer'having a thickness between 3 and 40 microns enabling fusion of the alu minum without destruction of the layer.
  • a semiconductor device comprising a semiconductive body, and a Wire-like element fused at one end to the semiconductive body, the outer wire portions consisting essentially of aluminum and containing a genetic aluminum oxide layer having a thickness between about 3 and 40 microns.
  • a 3. A device as set forth in claim 2 wherein the wirelike element comprises a core of a semiconductive material, an envelope of aluminum, and a surrounding aluminum oxide coating.
  • wirelike element comprises a core of an impurity material, an envelope of aluminum, and a surrounding aluminum oxide coating.
  • a semiconductor device comprising a semiconductive silicon body, and an aluminum wire-like element fused at one end to the semiconductive body, the outer wire portions containing a genetic aluminum oxide layer having a thickness between about 5 and 40 microns.
  • a method of making a semiconductor device comprising, providing a wire whose outer portions consist essentially of aluminum, subjecting said Wire to an oxidizing treatment'to provide on the aluminum portions a genetic'oxide' layer having a thickness enabling the aluminum to be fused without desruction of the oxide layer, and using an end of the said Wire to a semiconductive body.
  • a method of making a semiconductor device comprising providing a wire whose outer portions consist essentially of aluminum, subjecting said Wire to an oxidizing treatment to provide a'genetic oxide layer having a thickness of at least about 5 microns, placing a cut end of the said wire in contact with a semiconductive body, and heating the assembly at a temperature at which I the wireend fuses to the semiconductive body.
  • a method of making a semiconductor device comprising providing an aluminum wire, subjecting said Wire to an oxidiring'treatment to provide thereon a genetic aluminum oxide layer having a thickness between 3 and 40 microns, placing a cut end of the wire in contact with a silicon semiconductive body, and heating the assembly in an oven at a temperature above the eutectic temperature of the silicon-aluminum alloy and at which the 2,840,770 Jackson June 24, 1958 2,844,770 Vessem July 22, 1958 2,906,932 Fedotowsky et a1. Sept.

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  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Wire Bonding (AREA)
US745032A 1957-07-01 1958-06-27 Semi-conductive electrode system Expired - Lifetime US3015761A (en)

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NL218594 1957-07-01

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US (1) US3015761A (OSRAM)
BE (1) BE569023A (OSRAM)
CH (1) CH362752A (OSRAM)
DE (1) DE1068385B (OSRAM)
FR (1) FR1197494A (OSRAM)
GB (1) GB894672A (OSRAM)
NL (2) NL218594A (OSRAM)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4036485A (en) * 1969-08-11 1977-07-19 Licentia Patent-Verwaltungs-G.M.B.H. Jig

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB928110A (en) 1960-01-06 1963-06-06 Pacific Semiconductors Inc Semiconductor devices and methods for assembling them
DE1178520B (de) * 1961-08-24 1964-09-24 Philips Patentverwaltung Legierungsverfahren zur Herstellung von Halbleiteranordnungen

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2840770A (en) * 1955-03-14 1958-06-24 Texas Instruments Inc Semiconductor device and method of manufacture
US2844770A (en) * 1954-05-18 1958-07-22 Philips Corp Semi-conductive device and method of producing same
US2906932A (en) * 1955-06-13 1959-09-29 Sprague Electric Co Silicon junction diode

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE533564A (OSRAM) *
BE517459A (OSRAM) * 1952-02-07

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2844770A (en) * 1954-05-18 1958-07-22 Philips Corp Semi-conductive device and method of producing same
US2840770A (en) * 1955-03-14 1958-06-24 Texas Instruments Inc Semiconductor device and method of manufacture
US2906932A (en) * 1955-06-13 1959-09-29 Sprague Electric Co Silicon junction diode

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4036485A (en) * 1969-08-11 1977-07-19 Licentia Patent-Verwaltungs-G.M.B.H. Jig

Also Published As

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CH362752A (de) 1962-06-30
NL218594A (OSRAM)
DE1068385B (OSRAM) 1959-11-05
GB894672A (en) 1962-04-26
FR1197494A (fr) 1959-12-01
BE569023A (OSRAM)
NL98359C (OSRAM)

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