Hermetically sealed integrated circuit lead-on package configuration

• US 5,804,870 A
• Filed: 01/30/1995
• Issued: 09/08/1998
• Est. Priority Date: 06/26/1992
• Status: Expired due to Term

• Current Assignee: Tamiras Per Pte Ltd LLC (Intellectual Ventures LLC)
• Original Assignee: Staktek Corporation (Entorian Technologies)
• Inventors: Burns, Carmen D.
• Primary Examiner(s): Crane, Sara W.
• Assistant Examiner(s): POTTER, ROY KARL
• Application Number:
  US08/380,541
• Time in Patent Office: 1,317 Days
• Field of Search: 257/666, 257/675, 257/700, 257/704, 257/725
• US Class Current: 257/666
• CPC Class Codes: H01L 21/50 Assembly of semiconductor devices using processes or apparatus not provided for in a single one of the subgroups H01L21/06 - H01L21/326, e.g. sealing of a cap to a base of a container
• CPC Class Codes: H01L 2224/05554 being square
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) 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 2224/4824 Connecting between the body and an opposite side of the item with respect to the body
• CPC Class Codes: H01L 2224/4826 Connecting between the body and an opposite side of the item with respect to the body
• CPC Class Codes: H01L 2224/48472 the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
• CPC Class Codes: H01L 2224/48699 Principal constituent of the connecting portion of the wire connector being Aluminium (Al)
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2224/73215 Layer and wire connectors
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 23/04 characterised by the shape of the container or parts, e.g. caps, walls
• CPC Class Codes: H01L 23/057 the leads being parallel to the base
• CPC Class Codes: H01L 23/10 characterised by the material or arrangement of seals between parts, e.g. between cap and base of the container or between leads and walls of the container
• CPC Class Codes: H01L 23/13 characterised by the shape
• CPC Class Codes: H01L 23/36 Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks H01L23/28, H01L23/40, H01L23/42, H01L23/44, H01L23/46 take precedence; heating H01L23/345
• CPC Class Codes: H01L 23/4951 : Chip-on-leads or leads-on-chip techniques, i.e. inner lead fingers being used as die pad
• CPC Class Codes: H01L 23/49541 : Geometry of the lead-frame
• CPC Class Codes: H01L 23/49838 : Geometry or layout
• CPC Class Codes: H01L 23/552 : Protection against radiation, e.g. light or electromagnetic waves
• CPC Class Codes: H01L 23/556 : against alpha rays
• CPC Class Codes: H01L 23/66 : High-frequency adaptations
• 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 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 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01007 : Nitrogen [N]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/07802 : not being an ohmic electrical conductor
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/15153 : the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/15165 : Monolayer substrate
• CPC Class Codes: H01L 2924/1517 : Multilayer substrate
• CPC Class Codes: H01L 2924/15787 : Ceramics, e.g. crystalline carbides, nitrides or oxides
• CPC Class Codes: H01L 2924/16195 : Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 2924/3011 : Impedance
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding

Abstract

A hermetically sealed ceramic integrated circuit package and method for achieving same, the package including an internal lead frame attached to an integrated circuit die in a lead-on-chip configuration, an external lead frame attached to the package exterior in a lead-on-package configuration and a high temperature adhesive layer which attaches the internal lead frame to the integrated circuit die.

Claims

1. A hermetically sealed ceramic integrated circuit package having good thermal conductivity for efficiently transferring heat from an integrated circuit die contained therein, comprising:

an integrated circuit die having a face with integrated circuit connection pads thereon;

a ceramic housing, comprising a base, electrical connection portion and a seal ring, said integrated circuit die being mounted within said ceramic housing, said electrical connection portion having a plurality of conductive vias formed therein;

an internal lead frame attached to and disposed over a substantial portion of said face of said integrated circuit die, selected elements of said internal lead frame being connected to selected ones of said integrated circuit die connection pads, and to selected ones of said conductive vias, each of said vias extending from said connection portion through said ceramic housing base and terminating at an electrical contact disposed on said exterior surface of said housing base;

a cover attached to said ceramic housing seal ring, said cover and housing being hermetically sealed together; and

an external lead frame having a plurality of lead connection tips, said external lead frame being attached to an exterior surface of said ceramic housing base, said plurality of lead connection tips of said external lead frame being aligned with and electrically connected to selected ones of said electrical contacts disposed on said exterior surface of said ceramic housing base.

2. The package of claim 1, wherein said internal lead frame is attached to said face of said integrated circuit die with a high temperature adhesive.

3. The package of claim 1, wherein said external lead frame is comprised of copper alloy 195.

4. The package of claim 1, wherein said internal lead frame is attached to said face of said integrated circuit die with a polyimide tape having adhesive attached to both sides of said tape.

5. The package of claim 1, wherein said electrical contacts are made of gold.

6. The package of claim 1, wherein said external lead frame lead connection tips are flexible and are electrically connected to said selected electrical contacts by thermal compression bonding said lead connection tips to selected said electrical contacts.

7. The package of claim 1, wherein said internal lead frame is comprised of a plurality of substantially planar flexible electrical conductors.

8. The package of claim 1, wherein said internal lead frame electrical conductors are formed of sufficient length to provide for expansion or contraction of the elements of said packages without inducing tension in said conductors or the connection points between said conductors and said integrated circuit connection pads or said vias.

9. The package of claim 1, further comprising an electrically insulating layer disposed between said external surface of said ceramic housing base and said external lead frame, said insulating layer including apertures formed therein which correspond to selected ones of said electrical contacts disposed on said exterior surface of said ceramic housing base.

10. The package of claim 9, wherein said lead connection tips of said external lead frame are electrically connected to selected ones of said electrical contacts via said apertures formed in said insulating layer.

11. The package of claim 1, wherein said elements of said internal lead frame include an "S" shaped portion formed therein which allows for flexing of said lead frame elements during temperature cycling conditions.