Patent ID: 12255180

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed Embodiment. It will be apparent, however, that one or more Embodiments may be practiced without these specific details.

It is apparent that departures from specific designs and methods described and shown will suggest themselves to those skilled in the art and may be used without departing from the spirit and scope of the invention. The present invention is not restricted to the particular constructions described and illustrated, but should be construed to cohere with all modifications that may fall within the scope of the appended claims.

Embodiment

Please refer toFIGS.1A˜1C, andFIGS.1D,1D′ and1D″.FIG.1Ais a top view of a cross-shaped flexible circuit board according to an Embodiment of this invention.FIG.1Bis a cross-sectional view along with the cross-sectional line IB-IB′ shown inFIG.1A.FIG.1Cis a cross-sectional view along with the cross-sectional line IC-IC′ shown inFIG.1A.FIG.1Dis a cross-sectional view of a 3D package configuration1900according to an Embodiment of this present invention.FIG.1D′ is a cross-sectional view of another 3D package configuration1900′ according to an Embodiment of this invention.FIG.1D″ is a cross-sectional view of another 3D package configuration1900″ according to an Embodiment of this invention.

This present Embodiment discloses a 3D package configuration1900as shown inFIG.1D, comprising a package substrate60and a folded flexible circuit board structure1400vertically stacked on the package substrate60and electrically connected therewith. The folded flexible circuit board structure1400comprises a folded flexible circuit board200′, a first semiconductor die110and a plurality of second semiconductor dies including120A,120B,120C and120D. The folded flexible circuit board200′ was formed by folding a cross-shaped flexible circuit board200as shown inFIGS.1A˜1C comprising a flexible insulating substrate220, a circuit240formed on a surface of the flexible insulating substrate220and an insulating layer260overlaying the circuit240, wherein the cross-shaped flexible circuit board200has a first surface200A and a second surface200B opposite to each other, and the first surface200A includes a first die bonding zone and a plurality of second die bonding zones formed thereon, and the first die bonding zone includes a plurality of first die bonding pads131electrically connected to the circuit240, and each of the second die bonding zones includes a plurality of second die bonding pads132electrically connected to the circuit240, and the second surface200B under the first die bonding zone further comprises a plurality of package substrate bonding pads136, wherein each of the package substrate bonding pads136corresponding to each of the first die bonding pads131and electrically to each other through a first conductive hole140. The first semiconductor die110was bonded to the first die bonding zone and electrically connected to the circuit240through the first die bonding pads131. The second semiconductor dies including120A,120B,120C and120D were respectively bonded to each of the second die bonding zones and electrically connected to the circuit240through the second die bonding pads132therein.

According to this present Embodiment, the package substrate60can be for example but not limited to a lead frame, a Ball Grid Array (BGA) package substrate including a ceramic BGA package substrate, a plastic BGA package substrate, a metal BGA package substrate and a tape BGA package substrate, a Chip Scale Package (CSP) substrate or a Flip Chip (FC) package substrate.

The flexible circuit boards200of this present Embodiment comprises a first semiconductor die110bonded to the first die bonding zone, and a plurality of second semiconductor dies including120A,120B,120C and120D respectively bonded to each of the second die bonding zones. However, the flexible circuit board200according to other Embodiments of this invention can alternatively comprise more than one first semiconductor dies110bonded to the first die bonding zone, and one or more second semiconductor dies120A and/or120B and/or120C and/or120D bonded to each of the second die bonding zones, if necessary.

As shown inFIGS.1A˜1C and1D, the folded flexible circuit board structure1400as shown inFIG.1Dwas obtained by folding the cross-shaped flexible circuit board200shown inFIGS.1A˜1C in sequence to make the cross-shaped flexible circuit board200with the second semiconductor die120B be bonded thereon be folded above the first semiconductor die110, and then the cross-shaped flexible circuit board200with the second semiconductor die120A be bonded thereon be folded above the second semiconductor die120B, and then the cross-shaped flexible circuit board200with the second semiconductor die120C be bonded thereon be folded above the second semiconductor die120A, and then the cross-shaped flexible circuit board200with the second semiconductor die120D be bonded thereon be folded above the second semiconductor die120C, wherein the second semiconductor dies120B,120A,120C and120D were vertically stacked above the first semiconductor die110in sequence. The folded flexible circuit board structure1400was vertically stacked on the package substrate60through the package substrate bonding pads136and electrically connected therewith, and then placed into a jig for subsequent package treatment to generate a 3D package configuration1900as shown inFIG.1D.

Alternatively, as shown inFIGS.1A˜1C and1D′, according to another Embodiment of this invention, another folded flexible circuit board structure1400′ comprising a folded flexible circuit board200′, a first semiconductor die110and a plurality of second semiconductor dies including120A,120B,120C and120D as shown inFIG.1D′ was obtained by folding the cross-shaped flexible circuit board200as shown inFIGS.1A˜1C in sequence to make the cross-shaped flexible circuit board200with the second semiconductor die120A be bonded thereon be folded above the first semiconductor die110, and then the cross-shaped flexible circuit board200with the second semiconductor die120B be bonded thereon be folded above the second semiconductor die120A, and then the cross-shaped flexible circuit board200with the second semiconductor die120C be bonded thereon be folded above the second semiconductor die120B, and then the cross-shaped flexible circuit board200with the second semiconductor die120D be bonded thereon be folded above the second semiconductor die120C, wherein the second semiconductor dies120A,120B,120C and120D were vertically stacked above the first semiconductor die110in sequence. The folded flexible circuit board structure1400′ was vertically stacked on the package substrate60through the package substrate bonding pads136and electrically connected therewith, and then placed into a jig for subsequent package treatment to generate a 3D package configuration1900′ as shown inFIG.1D′.

Alternatively, as shown inFIGS.1A˜1C and1D″, according to another Embodiment of this invention, another folded flexible circuit board structure1400″ comprising a folded flexible circuit board200′, a first semiconductor die110and a plurality of second semiconductor dies including120A,120B,120C and120D as shown inFIG.1D″ was obtained by folding the cross-shaped flexible circuit board200as shown inFIGS.1A˜1C in sequence to make the cross-shaped flexible circuit board200with the second semiconductor die120A be bonded thereon be folded above the first semiconductor die110, and then the cross-shaped flexible circuit board200with the second semiconductor die120C be bonded thereon be folded above the second semiconductor die120A, and then the cross-shaped flexible circuit board200with the second semiconductor die120B be bonded thereon be folded above the second semiconductor die120C, and then the cross-shaped flexible circuit board200with the second semiconductor die120D be bonded thereon be folded above the second semiconductor die120B, wherein the second semiconductor dies120A,120C,120B and120D were vertically stacked above the first semiconductor die110in sequence. The folded flexible circuit board structure1400″ was vertically stacked on the package substrate60through the package substrate bonding pads136and electrically connected therewith, and then placed into a jig for subsequent package treatment to generate a 3D package configuration1900″ as shown inFIG.1D″.

The first semiconductor die110and the second semiconductor dies120A,120B,120C and120D of the 3D package configurations1900,1900′ and1900″ can respectively be for example but not limited to a CPU die, a GPU die, a DSP die, a MPU die, a MCU die, a DRAM die, a SRAM die, a Standard Logic IC die, an ASIC die for a special application, a sensing die with a specific sensing function, or a driving IC die.

The first die bonding pads131, the second die bonding pads132and the package substrate bonding pads136of the 3D package configurations1900,1900′ and1900″ are respectively for example but not limited to solder balls or metallic bumps formed by a material selected from one of the group consisting of tin, tin alloys including tin/copper alloy, tin/ITO alloy, tin/silver alloy, tin/bismuth alloy and tin/lead alloy, and conductive polymers.

The material for the flexible insulating substrate220of the 3D package configurations1900,1900′ and1900″ can be selected from for example but not limited to one of the group consisting of Polyester resin, Polyimide (PI), Modified Polyimide (MPI), Covalent Organic Framework (COF), Liquid Photo-Imageable (LPI), Liquid Crystal Polymer (LCP), Polytetrafluoroethylene (PTFE) and flexible epoxy bonded fiber-glass board, or combinations thereof.

The material for the circuit240of the 3D package configurations1900,1900′ and1900″ is selected from for example but not limited to one of the group consisting of copper, copper alloy, tinned copper, tin alloy, aluminum, aluminum alloys, gold and silver, or combinations thereof.

The above-mentioned 3D package configurations1900,1900′ and1900″, wherein the circuit240of the flexible circuit board200can be a single-layered circuit or a multiple-layered circuit, and the insulating layer260overlaying the circuit240can also be a single-layered insulating layer or a multiple-layered insulating layer.

According to another embodiment of this invention, additional adhesive layers can be coated on the first surface200A or the second surface200B of the flexible circuit board200of the 3D package configurations1900,1900′ and1900″ to fasten the folded flexible circuit board structures1400,1400′ and1400″ vertically stacked on the package substrate60.

According to other Embodiments of this invention, the second die bonding zones were formed on the second surface of the cross-shaped flexible circuit board200as shown inFIGS.2A˜2D, and a first semiconductor die110was bonded to the first die bonding zone on the first surface of the cross-shaped flexible circuit board200, and a plurality of second semiconductor dies including120A,120B,120C and120D were respectively bonded to each of the second die bonding zones on the second surface of the cross-shaped flexible circuit board200.FIG.2Ais a top view of a cross-shaped flexible circuit board according to another Embodiment of this invention.FIG.2Bis a bottom view of a cross-shaped flexible circuit board according to another Embodiment of this invention.FIG.2Cis a cross-sectional view of the cross-shaped flexible circuit board shown inFIG.2Aalong with the cross-sectional line IIB-IIB′ inFIG.2A.FIG.2Dis a cross-sectional view of the cross-shaped flexible circuit board shown inFIG.2Aalong with the cross-sectional line IIC-IIC′ inFIG.2A. Similarly, 3D package configurations2000,2000′ and2000″ as shown inFIG.2E,2E′ or2E″ comprising a package substrate60and a folded flexible circuit board structure1510,1510′ or1510″ vertically stacked on the package substrate60and electrically connected therewith were obtained. Each of the folded flexible circuit board structures1510,1510′ and1510″ comprises a folded flexible circuit board200″ obtained by folding the the cross-shaped flexible circuit board200shown inFIGS.2A˜2D, a first semiconductor die110and a plurality of second semiconductor dies including120A,120B,120C and120D. Each of the folded flexible circuit board structures1510,1510′ and1510″ was respectively obtained by folding the cross-shaped flexible circuit board200shown inFIGS.2A˜2D as similar methods mentioned above. Besides, the flexible circuit board200according to other Embodiments of this invention can alternatively comprise more than one first semiconductor dies110bonded to the first die bonding zone, and one or more second semiconductor dies120A and/or120B and/or120C and/or120D bonded to each of the second die bonding zones, if necessary.

As described in the above Embodiments, a novel 3D package configuration can be obtained by stacking a folded flexible circuit board structure on a package substrate and electrically connected therewith based on the foldable characteristics of the flexible circuit board, and the high temperature resistance of the flexible circuit board which is suitable for insulating layer process, metal layer process, photolithography process, etching and development process, to make conventional semiconductor dies such as CPU dies, GPU dies, DRAM dies, SRAM dies, tel-communication dies, standard logic IC dies, ASIC dies, various sensing IC dies, various driving IC and other semiconductor dies with various functions be bonded on one die and/or two side of a flexible circuit board and electrically connected therewith in advance.

Although particular Embodiments have been shown and described, it should be understood that the above discussion is not intended to limit the present invention to these Embodiments. Persons skilled in the art will understand that various changes and modifications may be made without departing from the scope of the present invention as literally and equivalently covered by the following claims.