Mold and method for encapsulation of electronic device

• US 6,770,163 B1
• Filed: 05/02/2002
• Issued: 08/03/2004
• Est. Priority Date: 09/08/2000
• Status: Expired due to Term

• Current Assignee: ASM Technology Singapore Pte Limited (ASMPT Ltd.)
• Original Assignee: ASM Technology Singapore Pte Limited (ASMPT Ltd.)
• Inventors: Vath, Charles Joseph III, Ho, Shu Chuen, Kuah, Teng Hock, Koh, Juay Sim, Hui, Man Ho, Lim, Loon Aik
• Primary Examiner(s): ORTIZ, ANGELA Y
• Application Number:
  US10/129,258
• Time in Patent Office: 824 Days
• Field of Search: 156/245, 264/250, 264/254, 264/259, 264/267, 264/271.1, 264/272.11, 264/272.15, 264/272.17, 264/328.4, 264/328.5, 425/116, 425/121, 425/129.1, 425/544, 438/107, 438/118
• US Class Current: 156/245
• CPC Class Codes: B29C 2045/14934 Preventing penetration of injected material between insert and adjacent mould wall sealing means between mould and article B29C45/14418
• CPC Class Codes: B29C 45/14655 connected to or mounted on a carrier, e.g. lead frame
• CPC Class Codes: H01L 21/565 Moulds
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• 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 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

Abstract

A mold (1) is for molding a one-sided encapsulated electronic device. The mold (1) includes a first mold section (2) defining a mold cavity (4), and a second mold section (3) including a first recessed portion (6) adapted to receive a layer of material (15) attached to a leadframe (10), but not the leadframe (10).

Claims

1. A mold for molding a one-sided encapsulated electronic device from a leadframe, a layer of material being attached to one side of the leadframe, the mold comprising:

a first mold section defining a mold cavity; and

a second mold section, the first and second mold sections configured to receive the leadframe therebetween for molding the one-sided encapsulated electronic device, the second mold section including a first recess sized to receive the entire layer of material attached to the leadframe and sized smaller than the leadframe so that the leadframe extends over the first recess without being received within the first recess.

2. A mold according to claim 1, wherein the second mold section includes a second recess sized to receive the entire leadframe, the first recess being located within the second recess.

3. A mold according to claim 1, wherein the layer of material has a thickness and the first recess has a depth that is greater than the thickness of the layer of material.

4. A mold according to claim 3, wherein the depth of the first recess is approximately 10% to 30% greater than the thickness of the layer of material.

5. A mold according to claim 4, wherein the depth of the first recess is approximately 15% to 30% greater than the thickness of the layer of material.

6. A mold according to claim 5, wherein the depth of the first recess is approximately 20% to 30% greater than the thickness of the layer of material.

7. A mold according to claim 6, wherein the depth of the first recess is approximately 25% greater than the thickness of the layer of material.

8. A method of forming a one-sided encapsulated electronic device, comprising:

forming a leadframe assembly by;

(i) attaching a layer of material to one side of a leadframe, the leadframe including contact portions,

(ii) attaching a die to a die attach portion of the leadframe on another side of the leadframe, the die including contact portions, and

(iii) bonding wires between the contact portions of the die and the contact portions of the leadframe;

inserting the leadframe assembly into a mold, the mold including a first mold section defining a mold cavity, and a second mold section including a first recess sized to receive the entire layer of material attached to the leadframe and sized smaller than the leadframe so that the leadframe extends over the first recess without being received within the first recess; and

inserting a molding material into the mold cavity of the first mold section to form the one-sided encapsulated electronic device.

9. A method according to claim 8, wherein the layer of material has a thickness and the first recess has a depth that is greater than the thickness of the layer of material.

10. A method according to claim 9, wherein the depth of the first recess is approximately 10% to 30% greater than the thickness of the layer of material.

11. A method according to claim 10, wherein the depth of the first recess is approximately 15% to 30% greater than the thickness of the layer of material.

12. A method according to claim 11, wherein the depth of the first recess is approximately 20% to 30% greater than the thickness of the layer of material.

13. A method according to claim 12, wherein the depth of the first recess is approximately 25% greater than the thickness of the layer of material.

14. A method according to claim 8, wherein a thickness of the layer of material is from 15 μ

m to 60 μ

m.

15. A method according to claim 14, wherein the thickness of the layer of material is from 30 μ

m to 40 μ

m.

16. A method according to claim 8, wherein the second mold section of the mold includes a second recess sized to receive the leadframe, the first recess of the second mold section being located with the second recess of the second mold section, the leadframe assembly being inserted into the mold such that the leadframe is located entirely within the second recess.

17. A method according to claim 8, wherein the layer of material is an adhesive film having an adhesive, the layer of material being attached to the leadframe via the adhesive.

18. A method according to claim 17, wherein the adhesive film is an adhesive tape.