Ultra high density integrated circuit packages

• US 6,168,970 B1
• Filed: 11/05/1999
• Issued: 01/02/2001
• Est. Priority Date: 08/01/1990
• Status: Expired due to Term

• Current Assignee: Entorian Technologies
• Original Assignee: Staktek Group L.P. (Entorian Technologies)
• Inventors: Burns, Carmen D.
• Primary Examiner(s): Picardat, Kevin M.
• Assistant Examiner(s): COLLINS, DEVEN M
• Application Number:
  US09/434,534
• Time in Patent Office: 424 Days
• Field of Search: 438/106, 438/121, 438/127
• US Class Current: 438/106
• CPC Class Codes: H01L 21/565 Moulds
• CPC Class Codes: H01L 2225/1029 the support being a lead frame
• CPC Class Codes: H01L 2225/1064 Electrical connections provided on a side surface of one or more of the containers
• CPC Class Codes: H01L 2225/107 Indirect electrical connections, e.g. via an interposer, a flexible substrate, using TAB printed circuits H05K1/00
• CPC Class Codes: H01L 2225/1094 Thermal management, e.g. cooling
• CPC Class Codes: H01L 23/4334 Auxiliary members in encapsulations H01L23/49568 takes precedence
• CPC Class Codes: H01L 23/564 Details not otherwise provided for, e.g. protection against moisture getters H01L23/26
• CPC Class Codes: H01L 25/10 the devices having separate containers
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H01L 2924/3511 Warping
• CPC Class Codes: H05K 7/023 Stackable modules

Abstract

Thin and durable level-one and level-two integrated circuit packages are provided. A thin and durable level-one package is achieved in one method involving a molding technique of evenly applying molding compound to an integrated circuit die element. The casing surrounding a die element may be reduced or eliminated in part to thin the level-one package provided any necessary steps are taken to ensure the integrity of the package. Moisture-barriers, as an example, may be provided to the upper and/or lower surfaces of the thin level-one package. Additionally, a thin level-one package may also be constructed with one or more metal layers to prevent warpage. These level-one packages may be aligned in a stacked configuration to form a thin and durable horizontal level-two package. Various thermal conductors may be thermally coupled to the level-two package to help dissipate heat.

Claims

1. A method of forming a thin integrated circuit package, comprising the steps of:

(a) providing an integrated circuit package which comprises an integrated circuit element surrounded by a casing, said package having a first and a second major surface, and a perimeter wall defining the package height; and

(b) reducing the height of said package by uniformly removing material from one or both of said major surfaces.

2. A method of forming a thin integrated circuit package, comprising the steps of:

(a) providing an integrated circuit package which comprises,

an integrated circuit element formed on a semiconductor substrate, said integrated circuit element having an upper surface, a lower surface, and a perimeter wall, and

a casing which surrounds said integrated circuit element, said casing having an upper surface, a lower surface and a perimeter wall; and

(b) uniformly removing material from said lower surface of said casing until said lower surface of said integrated circuit element is exposed.

3. The method of claim 2, further comprising the step of uniformly removing material from said upper surface of said casing.

4. The method of claim 2, further comprising the step of uniformly removing material from said lower surface of said integrated circuit element.

5. The method of claim 4, further comprising the step of uniformly removing material from said upper surface of said casing.

6. A method of forming a thin integrated circuit package, comprising the steps of:

(a) providing an integrated circuit package which comprises,

an integrated circuit element formed on a semiconductor substrate, said integrated circuit element having an upper surface, a lower surface, and a perimeter wall, and

a casing covering said upper surface and said perimeter wall of said integrated circuit element, said casing having an upper surface, and a perimeter wall; and

(b) uniformly removing material from said lower surface of said integrated circuit element.

7. The method of claim 6, further comprising the step of uniformly removing material from said upper surface of said casing.

8. A method of forming a modular integrated circuit package, comprising the steps of:

(a) providing a plurality of level-one integrated circuit packages each having a plurality of electrical interconnect leads extending therefrom;

(b) aligning said level-one packages in a stacked configuration so that said leads from said level-one packages are aligned in an array of columns;

(c) mounting a plurality of thermally and electrically conductive rails adjacent to and oriented with said columns; and

(d) thermally and electrically coupling said rails to some or all of said leads in said columns.

9. A method of forming a modular integrated circuit package, comprising the steps of:

(a) providing a plurality of level-one integrated circuit packages, each including an integrated circuit element formed on a semiconductor substrate, and a lead frame electrically coupled to said integrated circuit element and having a plurality of electrical interconnect leads extending therefrom which provide an electrical path to said integrated circuit element;

(b) rendering one or more select leads of the lead frame in each level-one package inactive;

(c) aligning said level-one packages in a stacked configuration so that said leads from said level-one packages are aligned in an array of columns; and

(d) electrically coupling all of said leads which are aligned in said columns and extend externally from said level-one packages.

10. The method of claim 9, wherein said leads have a section external to said package and a section internal to said package, and wherein said one or more select leads of each package are rendered inactive by disconnecting said external section.

11. The method of claim 9, wherein said leads have a section external to said package and a section internal to said package, and wherein said one or more select leads are rendered inactive by disconnecting said electrical path of said internal section of said select leads.

12. The method of claim 9, wherein said one or more select inactive leads of each level-one package provide a unique address for each package.

13. The method of claim 9, wherein said one or more select inactive leads of each level-one package provide a unique data word bit-position for each package.

14. A method of forming a modular integrated circuit package, comprising the steps of:

(a) providing a plurality of level-one integrated circuit packages, each including an integrated circuit element formed on a semiconductor substrate, and a lead frame electrically coupled to said integrated circuit element and having a plurality of electrical interconnect leads extending therefrom which provide an electrical path to said integrated circuit element;

(b) rendering one or more select leads of the lead frame in each level-one package inactive;

(c) aligning said level-one packages in a stacked configuration so that said leads from said level-one packages are aligned in an array of columns;

(d) mounting a plurality of thermally and electrically conductive rails adjacent to and oriented with said columns; and

(e) thermally and electrically coupling said rails to some or all of said leads in said columns and external to said level-one packages.

15. The method of claim 14, wherein said leads have a section external to said package and a section internal to said package, and wherein said one or more select leads of each package are rendered inactive by disconnecting said external section.

16. The method of claim 14, wherein said leads have a section external to said package and a section internal to said package, and wherein said one or more select leads are rendered inactive by disconnecting said electrical path of said internal section of said select leads.

17. The method of claim 14, wherein said one or more select inactive leads of each level-one package provide a unique address for each package.

18. The method of claim 14, wherein said one or more select inactive leads of each level-one package provide a unique data word bit-position for each package.