Magnetoelectric transducer

• US 4,908,685 A
• Filed: 03/15/1989
• Issued: 03/13/1990
• Est. Priority Date: 05/10/1985
• Status: Expired due to Term

• Current Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
• Original Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
• Inventors: Kajino, Takashi, Shibasaki, Ichiro
• Primary Examiner(s): James, Andrew J.
• Assistant Examiner(s): Crane, Sara W.
• Application Number:
  US07/325,129
• Time in Patent Office: 363 Days
• Field of Search: 357/27, 357/67, 357/71, 357/65
• US Class Current: 257/425
• CPC Class Codes: G01R 33/0052 Manufacturing aspects; Manufacturing of single devices, i.e. of semiconductor magnetic sensor chips devices based on galvano-magnetic effect or the like H10N50/85
• CPC Class Codes: G01R 33/07 Hall effect devices
• CPC Class Codes: H01L 2224/04042 Bonding areas specifically adapted for wire connectors, e.g. wirebond pads
• CPC Class Codes: H01L 2224/05082 Two-layer arrangements
• CPC Class Codes: H01L 2224/05155 Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/05554 being square
• CPC Class Codes: H01L 2224/05644 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/48644 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48744 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48844 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/73265 : Layer and wire connectors
• CPC Class Codes: H01L 2224/85207 : Thermosonic bonding
• CPC Class Codes: H01L 24/03 : Manufacturing methods
• CPC Class Codes: H01L 24/05 : of an individual bonding area
• CPC Class Codes: H01L 24/06 : of a plurality of bonding areas
• CPC Class Codes: H01L 24/45 : of an individual wire connector
• CPC Class Codes: H01L 24/73 : Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 : 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
• CPC Class Codes: H01L 2924/00015 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed as prior art
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01022 : Titanium [Ti]
• CPC Class Codes: H01L 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01024 : Chromium [Cr]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01032 : Germanium [Ge]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01042 : Molybdenum [Mo]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/10329 : Gallium arsenide [GaAs]
• CPC Class Codes: H01L 2924/15787 : Ceramics, e.g. crystalline carbides, nitrides or oxides
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/20752 : larger or equal to 20 microns less than 30 microns
• CPC Class Codes: H01L 2924/20753 : larger or equal to 30 microns less than 40 microns
• CPC Class Codes: H01L 2924/351 : Thermal stress
• CPC Class Codes: H10N 52/101 : Semiconductor Hall-effect devices

Abstract

A magnetoelectric transducer comprising a group III-V compound semiconductor thin film 14 of 0.1 μm to 10 μm thickness formed as a magnetic field sensing portion on a substrate 12 overlaying an organic insulating layer 13, and a multilayer wire bonding electrode including an ohmic electrode 16 formed on a required area of the thin film and a hard metal layer 17 and a bonding layer 18 which are laminated on the ohmic electrode.

Claims

1. A compound semiconductor magnetoelectric transducer comprising:

a substrate and an organic insulating layer overlaying said substrate;

a group III-V compound semiconductor layer of 0.1 to 10μ

m thickness disposed on said substrate and having a predetermined pattern to provide a magnetic field sensing portion;

a plurality of electrodes each formed of a laminated stack of three metal layers;

the first metal layer of said laminated stack being continuous to and in ohmic contact with said semiconductor layer and made of a material selected from the group consisting of Cu, Au, Au alloys and Au-Ge alloys;

the intermediate layer of said laminated stack providing a mechanical strength above a predetermined value and being formed on said first metal layer and made of a material selected from the group consisting of Ni, Cu and their alloys;

the third layer of said laminated stack being provided for wire bonding and being formed on said intermediate layer and made of Au; and

said first metal layer, said intermediate metal layer and said third layer each having a thickness of between about 2-5 μ

m.

2. The compound semiconductor magnetoelectric transducer as set forth in claim 1 wherein said mechanical strength providing metal layer and said bonding surface providing metal layer comprise a single metal layer, disposed immediately below and adjacent to said wire bonding electrode, in ohmic contact with said compound semiconductor layer, said single metal layer having a thickness sufficient to resist at least an ultrasonic bonding force.

3. The compound semiconductor magnetoelectric transducer as set forth in claim 1 including an inorganic thin insulating layer disposed between said compound semiconductor layer and said organic insulating layer.

4. The compound semiconductor magnetoelectric transducer as set forth in claim 1 including first and second inorganic thin insulating layers disposed adjacent to the upper and lower surfaces of said compound semiconductor layer to sandwich said compound semiconductor layer therebetween.

5. The compound semiconductor magnetoelectric transducer as set forth in claim 1 wherein said compound semiconductor layer is formed of a group III-V compound semiconductor of high electron mobility containing arsenic.

6. The compound semiconductor magnetoelectric transducer as set forth in claim 1 wherein said compound semiconductor layer contains at least one of InSb, InAs and InAsP.

7. The compound semiconductor magnetoelectric transducer as set forth in claim 4 wherein said inorganic insulating layer has a thickness of 500 Å

to 2 μ

m.

8. The compound semiconductor magnetoelectric transducer as set forth in claim 1 wherein said substrate is formed of ferrite or ceramics.