Integrated circuit package with transparent encapsulant and method for making thereof

• US 20050167790A1
• Filed: 12/29/2004
• Published: 08/04/2005
• Est. Priority Date: 12/31/2003
• Status: Abandoned Application

• Current Assignee: Carsem (M) SDN BHD (Hong Leong Company (Malaysia) Bhd.)
• Original Assignee: Carsem (M) SDN BHD (Hong Leong Company (Malaysia) Bhd.)
• Inventors: Khor, Lek Ah, Thum, Kong Min, Tung, Mun Hong, Cheong, Tuck Mun, Chan, Meng Boon, Lee, Huat Kock
• Application Number:
  US11/027,920
• Publication Number:
  US 20050167790A1
• Time in Patent Office: Days
• US Class Current: 257/666
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/83 using a layer connector
• CPC Class Codes: H01L 2224/85 using a wire connector
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 23/3107 the device being completely enclosed
• CPC Class Codes: H01L 23/49548 Cross section geometry H01L23/49562 takes precedence
• CPC Class Codes: H01L 24/48 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 24/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 27/14618 Containers
• 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 2924/01012 : Magnesium [Mg]
• CPC Class Codes: H01L 2924/01019 : Potassium [K]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• 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 2924/12042 : LASER
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/16195 : Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/18301 : being an anchoring portion, i.e. mechanical interlocking between the encapsulation resin and another package part
• CPC Class Codes: H01L 2924/207 : Diameter ranges

Abstract

IC package with transparent encapsulant and method for making thereof. The IC package includes a die pad including a pad bottom surface, a die disposed on the die pad and including an integrated circuit, a plurality of leads including a plurality of lead bottom surfaces, a plurality of conductive wires connecting the die and the plurality of leads, and an encapsulant material. The encapsulant material is transparent for visible wavelengths. The pad bottom surface is exposed without being covered by the encapsulant material, and the plurality of lead bottom surfaces each are exposed without being covered by the encapsulant material.

Claims

1. A method for making an IC package with transparent encapsulant, the method comprising:

providing a leadframe, the leadframe including a first die pad and a second die pad;

disposing a first die on the first die pad and a second die on the second die pad;

forming a cavity on the leadframe, the cavity including the first die pad and the second die pad;

injecting an encapsulant material into the cavity;

cutting the injected encapsulant material and the leadframe to form a first IC package and a second IC package;

wherein;

the encapsulant material is transparent for visible wavelengths; and

the injecting an encapsulant material is performed at an encapsulant temperature ranging from 140°

c to 160°

c.

2. The method of claim 1 wherein the injecting an encapsulant material comprising transferring the encapsulant material at a pressure ranging from 1100 psi to 1400 psi.

3. The method of claim 2 wherein the injecting an encapsulant material is further performed in an environment with a dust count lower than or equal to about 30 k parts per million (PPM).

4. The method of claim 1 wherein the encapsulant material is configured to provide a transmission rate higher than or equal to 80% for a wavelengths longer than or equal to 350 nm.

5. The method of claim 1 wherein the encapsulant material comprises a plastic.

6. The method of claim 1 wherein the leadframe comprises an outer frame surrounding a plurality of die pads, the plurality of die pads including the first die pad and the second die pad.

7. The method of claim 6 wherein the plurality of die pads forms a two dimensional array.

8. The method of claim 6 wherein the forming a cavity comprises forming a plurality of side boundaries approximately on the outer frame.

9. The method of claim 6 wherein the outer frame comprises a plurality of elongated openings around the circumference of the outer frame.

10. An apparatus for making an IC package with transparent encapsulant, the apparatus comprising:

a leadframe, the leadframe including an outer frame and a plurality of connecting bars, the plurality of connecting bars attached to the outer frame and defining a plurality of inner frames arranged in a matrix pattern within the outer frame, the plurality of inner frames including a plurality of die pads respectively;

a plurality of side boundaries located approximately on the outer frame;

wherein;

the plurality of side boundaries, the outer frame, and the plurality of inner frames form at least parts of a cavity;

the cavity is at least partially filled with a transparent encapsulant material; and

the encapsulant material is transparent for visible wavelengths.

11. The apparatus of claim 10 wherein the encapsulant material is configured to provide a transmission rate higher than or equal to 80% for a wavelengths longer than or equal to 350 nm.

12. The apparatus of claim 10 wherein the encapsulant material comprises a plastic.

13. The apparatus of claim 10 wherein the cavity is configured to receive an injection of the transparent encapsulant material performed at an encapsulant temperature ranging from 140°

c to 160°

c.

14. The apparatus of claim 13 wherein the cavity is further configured to receive the injection of the transparent encapsulant material at a pressure ranging from 1100 psi to 1400 psi.

15. The apparatus of claim 14 wherein the cavity is further configured to receive the injection of the transparent encapsulant material further performed in an environment with a dust count lower than or equal to about 30 k parts per million (PPM).

16. The apparatus of claim 10 wherein the outer frame comprises a plurality of elongated openings around the circumference of the outer frame.

17. An IC package with transparent encapsulant, the package comprising:

a die pad including a pad bottom surface;

a die disposed on the die pad and including an integrated circuit;

a plurality of leads including a plurality of lead bottom surfaces;

a plurality of conductive wires connecting the die and the plurality of leads; and

an encapsulant material;

wherein;

the encapsulant material is transparent for visible wavelengths;

the pad bottom surface is exposed without being covered by the encapsulant material;

the plurality of lead bottom surfaces each are exposed without being covered by the encapsulant material.

18. The IC package of claim 17 wherein the encapsulant material is configured to provide a transmission rate higher than or equal to 80% for a wavelength longer than or equal to 350 nm.

19. The IC package of claim 18 wherein the encapsulant material comprises a plastic.

20. The IC package of claim 17 wherein:

the die is disposed on the die pad through a bonding layer;

the die pad includes a pad plating layer;

the plurality of leads include a plurality of lead plating layers respectively.