Integrated Circuit Package with Sensor and Method of Making

• US 20170253476A1
• Filed: 05/23/2017
• Published: 09/07/2017
• Est. Priority Date: 05/27/2015
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Shibuya, Makoto, Nguyen, Luu, Nakanishi, Noboru
• Granted Patent: US 10,077,186 B2
• Time in Patent Office: Days
• CPC Class Codes: B81B 2201/0214 Biosensors; Chemical sensors
• CPC Class Codes: B81B 2203/0338 Channels
• CPC Class Codes: B81B 2207/098 Arrangements not provided for in groups B81B2207/092 - B81B2207/097
• CPC Class Codes: B81B 7/0038 using materials for controlling the level of pressure, contaminants or moisture inside of the package, e.g. getters
• CPC Class Codes: B81C 1/00285 using materials for controlling the level of pressure, contaminants or moisture inside of the package, e.g. getters
• CPC Class Codes: B81C 2203/0154 Moulding a cap over the MEMS device
• CPC Class Codes: G01N 33/0009 General constructional details of gas analysers, e.g. portable test equipment devices for withdrawing samples in the gaseous state G01N1/22
• CPC Class Codes: H01L 2224/291 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
• 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 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 23/16 Fillings or auxiliary members in containers or encapsulations, e.g. centering rings H01L23/42, H01L23/552 take precedence
• CPC Class Codes: H01L 23/3121 a substrate forming part of the encapsulation
• 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 2924/014 Solder alloys
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/1815 Shape

Abstract

An integrated circuit (“IC”) package comprising an IC die having a top surface and a bottom surface, an elongate member having opposite first and second end portions and a mid portion. The mid portion is positioned proximate the top surface of the IC die. The IC package also includes an encapsulant block having a top surface, a bottom surface and opposite first and second lateral side surfaces. The encapsulant block encapsulates the IC die and the elongate member. Either or both of the first and second end portions of the elongate member are exposed.

Claims

1. An integrated circuit (“

IC”

) package comprising;

an IC die having a top surface and a bottom surface;

an elongate member having opposite first and second end portions and a mid portion, said mid portion engaging said top surface of said IC die; and

an encapsulant block having a top surface, a bottom surface and opposite first and second lateral side faces, said encapsulant block encapsulating said IC die and said elongate member with at least one of said first and second end portions of said elongate member exposed;

said IC die comprising a sensor die having a sensing element on said top surface thereof, said elongate member being constructed and arranged to transmit gas therethrough to said sensing element;

said first and second end portions of said elongate member being exposed at opposite lateral side surfaces of said encapsulant block;

said elongate member being one of;

a tubular member, with at least one hole in said mid portion thereof that is constructed from at least one of;

carbon-nylon composite, epoxy resin and fluorine-containing rubber; and

a porous member adapted to transmit gas therethrough and constructed from at least one of polytetrafluoroethylene (“

PTFE”

) and porous ceramic; and

a leadframe having a die pad and a plurality of leads, said IC die bottom surface being attached to said die pad, said die pad and said leads being exposed at said bottom surface of said encapsulant block wherein said IC die comprises a plurality of electrical contact pads on at least one exterior surface thereof that are wire bonded to at least one of said plurality of leadframe leads.

2. A method of making an integrated circuit (“

IC”

) package comprising;

attaching to an IC die mounted on a leadframe an elongate member that is adapted to transmit gas to a top surface of the IC die; and

encapsulating the IC die, elongate member and leadframe in mold compound in a manner that leaves surface portions of a die pad and leads of the leadframe and end portions of the elongate member exposed.

3. The method of claim 2 wherein said attaching comprises attaching a plurality of elongate members to a plurality of integrated circuit dies mounted on a plurality of leadframes on a leadframe strip, wherein said encapsulating comprises encapsulating said plurality of dies and said plurality of elongate members in a single slab of encapsulant.

4. The method of claim 3 further comprising singulating the single slab of encapsulant and the leadframe strip and the elongate members so as to provide a plurality of IC packages each having an elongate member mounted on an IC die mounted on a leadframe and encapsulated in an encapsulant block with opposite ends of the elongate member exposed through opposite lateral side faces of the encapsulant block.

5. The method of claim 2 wherein said attaching comprises attaching a tubular member.

6. The method of claim 5 wherein said attaching further comprises:

forming a hole at a mid portion of the tubular member;

placing the portion of the tubular member with the hole therein in contact with a sensor element surface of the IC die; and

providing a vacuum in the tubular member to hold the tubular member in engagement with the IC die.

7. The method of claim 5 wherein said attaching comprises attaching the tubular member to the IC die with at least one of solder and an adhesive compound.

8. The method of claim 7 wherein said attaching comprises attaching a porous member.

9. The method of claim 8 wherein attaching a porous member comprises attaching a porous member with a generally rectangular cross section.

10. A method of determining the value of a parameter of gas in a local environment with an encapsulated integrated circuit sensor assembly comprising:

passing gas from the local environment to a sensing element inside the encapsulated sensor assembly through an elongate member in fluid communication with the local environment

11. An integrated circuit (“

IC”

) package comprising;

an IC die having a top surface and a bottom surface;

an elongate member having opposite first and second end portions and a mid portion, said mid portion positioned proximate said top surface of said IC die;

an encapsulant block having a top surface, a bottom surface and opposite first and second lateral side faces, said encapsulant block encapsulating said IC die and said elongate member with at least one of said first and second end portions of said elongate member exposed; and

a leadframe having a die pad and a plurality of leads, said IC die bottom surface being attached to said die pad, said die pad and said leads being exposed at said bottom surface of said encapsulant block, wherein said IC die comprises a plurality of electrical contact pads on at least one exterior surface thereof that are wire bonded to at least one of said plurality of leadframe leads.

12. The IC package of claim 11, said IC die comprising a sensor die having a sensing element on said top surface thereof, said elongate member being constructed and arranged to transmit gas there through to said sensing element.

13. The IC package of claim 11 wherein both of said first and second end portions of said elongate member are exposed at opposite lateral side surfaces of said encapsulant block.

14. The IC package of claim 11 wherein said elongate member Is a tubular member.

15. The IC package of claim 14 wherein said tubular member has at least one hole in said mid portion thereof.

16. The IC package of claim 15 wherein said tubular member is constructed from at least one of:

carbon-nylon composite, epoxy resin and fluorine-containing rubber.

17. The IC package of claim 14 wherein said tubular member defines a fluid passage extending between said first and second end portions thereof.

18. The IC package of claim 11 wherein said elongate member is a porous member adapted to transmit gas there through.

19. The IC package of claim 18 wherein said porous member is constructed of polytetrafluoroethylene (“

PTFE”

).

20. The IC package of claim 11 wherein said encapsulant block is composed of mold compound.