Process for mounting electronic device and semiconductor device

• US 6,780,677 B2
• Filed: 08/21/2002
• Issued: 08/24/2004
• Est. Priority Date: 03/27/1997
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd., Hitachi Hokkai Semiconductor, Ltd. (Renesas Electronics Corporation)
• Original Assignee: Hitachi, Ltd., Hitachi Hokkai Semiconductor, Ltd. (Renesas Electronics Corporation)
• Inventors: Imasu, Satoshi, Yamagiwa, Akira, Yoshida, Ikuo, Hayashida, Tetsuya, Takeura, Shinobu
• Primary Examiner(s): Zarneke, David A.
• Application Number:
  US10/224,339
• Publication Number:
  US 20020192865A1
• Time in Patent Office: 734 Days
• Field of Search: 438/108, 438/106, 438/118, 438/119, 174/259, 174/260, 174/263, 361/765, 361/767, 361/768, 361/784, 361/792
• US Class Current: 438/118
• CPC Class Codes: H01L 21/563 Encapsulation of active face of flip-chip device, e.g. underfilling or underencapsulation of flip-chip, encapsulation preform on chip or mounting substrate
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/05552 in top view
• CPC Class Codes: H01L 2224/05567 the external layer being at least partially embedded in the surface
• CPC Class Codes: H01L 2224/05571 the external layer being disposed in a recess of the surface
• CPC Class Codes: H01L 2224/05572 the external layer extending out of an opening
• CPC Class Codes: H01L 2224/05573 Single external layer
• CPC Class Codes: H01L 2224/05624 Aluminium [Al] as principal constituent
• CPC Class Codes: H01L 2224/1134 Stud bumping, i.e. using a wire-bonding apparatus
• CPC Class Codes: H01L 2224/13099 Material
• CPC Class Codes: H01L 2224/13111 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/13116 Lead [Pb] as principal constituent
• CPC Class Codes: H01L 2224/13144 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16237 the bump connector connecting to a bonding area disposed in a recess of the surface of the item
• CPC Class Codes: H01L 2224/29111 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/2919 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45 of an individual wire connector
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48 : of an individual wire connector
• 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 2224/48599 : Principal constituent of the connecting portion of the wire connector being Gold (Au)
• CPC Class Codes: H01L 2224/49 : of a plurality of wire connectors
• CPC Class Codes: H01L 2224/49109 : outside the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73103 : Bump and layer connectors
• CPC Class Codes: H01L 2224/73203 : Bump and layer connectors
• CPC Class Codes: H01L 2224/73204 : the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2224/73265 : Layer and wire connectors
• CPC Class Codes: H01L 2224/81191 : wherein the bump connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83101 : as prepeg comprising a layer connector, e.g. provided in an insulating plate member
• CPC Class Codes: H01L 2224/83191 : wherein the layer connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83192 : wherein the layer connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2225/1023 : the support being an insulating substrate
• CPC Class Codes: H01L 23/13 : characterised by the shape
• CPC Class Codes: H01L 23/24 : solid or gel at the normal operating temperature of the device H01L23/3135 takes precedence
• CPC Class Codes: H01L 23/49811 : Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads H01L23/49827 takes precedence
• CPC Class Codes: H01L 23/5383 : Multilayer substrates H01L23/5385 takes precedence; multilayer metallisation on monolayer substrates H01L23/538
• CPC Class Codes: H01L 24/05 : of an individual bonding area
• CPC Class Codes: H01L 24/29 : of an individual layer connector
• CPC Class Codes: H01L 24/32 : of an individual layer connector
• CPC Class Codes: H01L 24/45 : of an individual wire connector
• CPC Class Codes: H01L 24/48 : of an individual wire connector
• CPC Class Codes: H01L 24/49 : of a plurality of wire connectors
• CPC Class Codes: H01L 25/105 : the devices being of a type provided for in group H01L27/00
• 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 2924/00013 : Fully indexed content
• 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 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• 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 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01073 : Tantalum [Ta]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/0132 : Binary Alloys
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/15153 : the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/1517 : Multilayer substrate
• CPC Class Codes: H01L 2924/15174 : in different layers of the multilayer substrate
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/1579 : with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19043 : being a resistor
• CPC Class Codes: H01L 2924/30105 : Capacitance
• CPC Class Codes: H01L 2924/351 : Thermal stress
• CPC Class Codes: H05K 1/0271 : Arrangements for reducing stress or warp in rigid printed circuit boards, e.g. caused by loads, vibrations or differences in thermal expansion
• CPC Class Codes: H05K 1/111 : Pads for surface mounting, e.g. lay-out
• CPC Class Codes: H05K 1/112 : directly combined with via connections
• CPC Class Codes: H05K 1/114 : Pad being close to via, but not surrounding the via
• CPC Class Codes: H05K 2201/0133 : Elastomeric or compliant polymer
• CPC Class Codes: H05K 2201/091 : Locally and permanently deformed areas including dielectric material
• CPC Class Codes: H05K 2201/09472 : Recessed pad for surface mounting; Recessed electrode of component
• CPC Class Codes: H05K 2201/0949 : Pad close to a hole, not surrounding the hole
• CPC Class Codes: H05K 2201/09536 : Buried plated through-holes, i.e. plated through-holes formed in a core before lamination
• CPC Class Codes: H05K 2201/0959 : Plated through-holes or plated blind vias filled with insulating material
• CPC Class Codes: H05K 2201/10674 : Flip chip
• CPC Class Codes: H05K 2203/1581 : Treating the backside of the PCB, e.g. for heating during soldering or providing a liquid coating on the backside
• CPC Class Codes: H05K 3/3436 : having an array of bottom contacts, e.g. pad grid array or ball grid array components
• CPC Class Codes: H05K 3/4007 : Surface contacts, e.g. bumps H05K3/4092 takes precedence; deposition of finish layers on pads H05K3/24; forming solder bumps H05K3/3457
• CPC Class Codes: H05K 3/4602 : characterized by a special circuit board as base or central core whereon additional circuit layers are built or additional circuit boards are laminated
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49144 : by metal fusion
• CPC Class Codes: Y10T 29/49146 : with encapsulating, e.g., potting, etc.

Abstract

An electronic device comprising a semiconductor chip which is fixed to the mounting face of a wiring board through an adhesive and in which external terminals are electrically connected with electrode pads of the wiring board through bump electrodes. Recesses are formed in the electrode pads, and in the recesses the electrode pads and the bump electrodes are connected. The electrode pads are formed over the surface of a soft layer, and the recesses are formed by elastic deformation of the electrode pads and the soft layer.

Claims

1. A method of fabricating an electronic device having a wiring board mounted a first device and a second device thereon, comprising the steps of:

preparing the wiring board having a rigid substrate, a soft layer softer than the rigid substrate formed on the rigid substrate, a plurality of electrode pads formed on the soft layer;

preparing the first device having a plurality of bumps;

positioning the first device on the wiring board so as to arrange the bumps on the electrode pads;

after the step of positioning the first device, mounting the first device to the wiring board by thermocompression bonding using a heater so as to form recesses in the electrode pads by pressure of the bumps, connecting the bumps with the electrode pads in the recesses and filling between the first device and the wiring board with resin;

preparing the second device having a plurality of external terminals;

positioning the second device on the wiring board so as to arrange the external terminals on the electrode pads through pasty solder, respectively; and

after the step of positioning the second device, melting the pasty solder by conducting a heat treatment and fixing the external terminals with the electrode pads by solder.

2. A method of fabricating an electronic device according to claim 1, wherein the bumps are fixed to the first device and pressed to the electrode pads on the soft layer.

3. A method of fabricating an electronic device according to claim 2, wherein the bumps are made of gold.

4. A method of fabricating an electronic device according to claim 2, wherein the wiring board having a passivation film formed on the soft layer arranged around each of the electrode pads connecting the external terminals of the second device.

5. A method of fabricating an electronic device according to claim 2, wherein the first device having a semiconductor chip, elements and a plurality of external terminals formed on a main surface of the semiconductor ship, and

wherein the bumps are fixed on the external terminals of the semiconductor chip.

6. A method of fabricating an electronic device according to claim 1, wherein the second device having a semiconductor chip, a plurality if leads each having an inner portion and an outer portion, a plurality of wires electrically connecting the leads and the semiconductor chip, a resin encapsulating the semiconductor chip, the inner portions of the leads and the wires, and

wherein the external terminals of the second device are comprised of the outer portions of the leads.

7. A method of fabricating an electronic device according to claim 2, wherein the wiring board having a plurality of wirings formed on the soft layer, a passivation film that covers the wirings and the soft layer, the electrode pads being electrically connected to the plurality of wirings.