Super low profile package with stacked dies

• US 6,731,015 B2
• Filed: 12/27/2001
• Issued: 05/04/2004
• Est. Priority Date: 08/01/2001
• Status: Expired due to Term

• Current Assignee: Siliconware Precision Industries Co., Ltd.
• Original Assignee: Siliconware Precision Industries Co., Ltd.
• Inventors: Wu, Chi-Chuan, Her, Tzong-Dar
• Primary Examiner(s): Jackson, Jerome
• Assistant Examiner(s): Landau, Matthew C
• Application Number:
  US10/026,452
• Publication Number:
  US 20030025199A1
• Time in Patent Office: 859 Days
• Field of Search: 257/707, 257/777, 257/778, 257/724, 257/796, 257/713, 257/719, 257/720, 257/676, 257/706, 438/122
• US Class Current: 257/796
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/32145 the bodies being stacked
• 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 2224/48227 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 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 2225/0651 Wire or wire-like electrical connections from device to substrate
• CPC Class Codes: H01L 2225/06513 Bump or bump-like direct electrical connections between devices, e.g. flip-chip connection, solder bumps
• CPC Class Codes: H01L 2225/06572 Auxiliary carrier between devices, the carrier having an electrical connection structure
• CPC Class Codes: H01L 2225/06582 Housing for the assembly, e.g. chip scale package [CSP]
• CPC Class Codes: H01L 2225/06586 Housing with external bump or bump-like connectors
• CPC Class Codes: H01L 2225/06589 Thermal management, e.g. cooling
• CPC Class Codes: H01L 23/3128 the substrate having spherical bumps for external connection
• 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 23/4334 Auxiliary members in encapsulations H01L23/49568 takes precedence
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 25/0657 Stacked arrangements of devices
• 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 2924/14 : 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 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/1532 : the connection portion being formed on the die mounting surface of the substrate
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/207 : Diameter ranges
• CPC Class Codes: H01L 2924/3011 : Impedance

Abstract

A super low profile package with stacked dies comprises a substrate, a heat spreader, a first die, a second die, a molding compound, and a number of solder balls. The substrate has a cavity, a top surface and a bottom surface opposite to the top surface. The heat spreader is connected to the bottom surface of the substrate, and a portion of the heat spreader opposite to the cavity serves as a die pad. The first die seated in the cavity is attached to the die pad while the second die seated in the cavity is attached to the first die, and both dies are wire-bonded to the substrate for electrical connection. The molding compound fills the cavity and encapsulates the first die, the second die, the heat spreader, and part of the bottom surface of the substrate. Numerous solder balls are attached to the bottom surface of the substrate. The benefits resulting from the package of the invention include a reduction of profile, a simple manufacturing process, and a low prime cost.

Claims

1. A super low profile package with stacked dies, comprising:

a substrate having a through cavity in its center and having a top surface and a bottom surface opposite to the top surface;

a heat spreader, which comprises;

a base portion, and serving as a die pad for providing support; and

an extending portion, radiating from the base portion and fixing the heat spreader onto the bottom surface of the substrate, so that the heat spreader is supported by the substrate by way of the extending portion;

a first die seated in the cavity, wherein the first die is attached to the die pad and electrically connected to the substrate;

a second die seated in the cavity, wherein the second die is attached to the first die and electrically connected to the substrate, wherein the first die and the second die are disposed above the heat spreader;

a molding compound filling the cavity and encapsulating the first die, the second die, the heat spreader, and part of the bottom surface of the substrate; and

a plurality of solder balls attached directly to the bottom surface of the substrate, wherein the heat spreader and the solder balls are both disposed on the same side of the substrate.

2. The super low profile package according to claim 1, wherein the bottom surface of the substrate further has a ground ring for ground connection, and the extending portion of the heat spreader connects and fixes the heat spreader to the ground ring.

3. The super low profile package according to claim 1, wherein the first die is electrically connected to the substrate by a wire.

4. The super low profile package according to claim 1, wherein the second die is electrically connected to the substrate by a wire.

5. The super low profile package according to claim 1, wherein the first die with an active surface facing downward is connected to the die pad by an adhesive.

6. The super low profile package according to claim 1, wherein the second die with an active surface facing downward is connected to the first die by an adhesive, and active surfaces of the first die and the second dies both are facing the same direction.

7. The super low profile package according to claim 1, wherein the first die is connected to the second die through a plurality of second solder balls in accordance with a flip chip arrangement.

8. The super low profile package according to claim 1, wherein a portion of the heat spreader is exposed to the atmosphere.

9. A super low profile package with stacked dies, comprising:

a substrate having a through cavity in its center and having a top surface and a bottom surface opposite to the top surface;

a heat spreader, which comprises;

a base portion, and serving as a die pad for providing support; and

an extending portion, radiating from the base portion and connecting and fixing the heat spreader to the bottom surface of the substrate, so that the heat spreader is supported by the substrate by way of the extending portion;

a first die seated in the cavity, wherein the first die is attached to the die pad and electrically connected to the substrate;

a second die seated in the cavity, wherein the second die is attached to the first die and electrically connected to the substrate, and a back surface of the second die is exposed to the atmosphere;

a molding compound filling the cavity and encapsulating the first die, the second die, the heat spreader, and part of the bottom surface of the substrate; and

a plurality of solder balls attached to the bottom surface of the substrate.

10. The super low profile package according to claim 9, wherein the bottom surface of the substrate further has a ground ring for ground connection, and the extending portion of the heat spreader connects and fixes the heat spreader to the ground ring.

11. The super low profile package according to claim 9, wherein the first die is electrically connected to the substrate by a wire.

12. The super low profile package according to claim 9, wherein the second die is electrically connected to the substrate by a wire.

13. The super low profile package according to claim 9, wherein the first die with an active surface facing downward is connected to the die pad by an adhesive.

14. The super low profile package according to claim 9, wherein the second die with an active surface facing downward is connected to the first die by an adhesive, and active surfaces of the first die and the second dies both are facing the same direction.

15. The super low profile package according to claim 9, wherein the first die is connected to the second die through a plurality of second solder balls in accordance with a flip chip arrangement.

16. A super low profile package with stacked dies, comprising:

a substrate having a through cavity in its center and having a top surface and a bottom surface opposite to the top surface;

a heat spreader, a portion of which is exposed to the atmosphere, wherein the heat spreader comprises;

a base portion, and serving as a die pad for providing support; and

an extending portion, radiating from the base portion and connecting and fixing the heat spreader to the bottom surface of the substrate, so that the heat spreader is supported by the substrate by way of the extending portion;

a first die seated in the cavity, wherein the first die is attached to the die pad and electrically connected to the substrate;

a second die seated in the cavity, wherein the second die is attached to the first die and electrically connected to the substrate;

a molding compound filling the cavity and encapsulating the first die, the second die, the heat spreader, and part of the bottom surface of the substrate; and

a plurality of solder balls attached to the bottom surface of the substrate;

wherein the package is further assembled to a printed circuit board (PCB) by thermally connecting the exposed heat spreader and a ground layer of the PCB through a layer of epoxy resin.