This application claims under 35 U.S.C. §119(a) the benefit of Taiwanese Application No. 098146227 filed Dec. 31, 2009 the entire contents of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to semiconductor package structures, and more particularly, to a semiconductor package structure characterized by high quality of wire bonding but not susceptible to solder bridging.
2. Description of Related Art
In a conventional lead frame based semiconductor package such as a QFN (Quad Flat Non-lead) package, a semiconductor chip is attached and wire-bonded to a lead frame and encapsulated by an encapsulant, and metal portions around the lead frame are exposed from the encapsulant to serve as contact pads for connection with an external device. Such a semiconductor package structure is advantageously characterized by reduced size, improved electrical performance, and wide application in the industry.
Referring to
Further, the semiconductor package structure 1 cannot provide array arranged contact pads and accordingly cannot provide a semiconductor package structure with high density I/O connections.
Accordingly, U.S. Pat. Nos. 6,498,099, 7,049,177, 6,238,952, 6,700,188 and 6,777,265 disclose a semiconductor package structure, as shown in
However, although a certain gap is provided between the contact pads and the circuit board and array-arranged contact pads are provided, since long bonding wires are required to electrically connect the semiconductor chip to the contact pads located far away, it adversely affects the electrical performance of the package structure. Further, due to tangling of the bonding wires, it is difficult for the package structure to provide high density I/O connections.
Therefore, it is imperative to overcome the above drawbacks of the prior art.
In view of the above drawbacks of the prior art, the present invention provides a semiconductor package structure, which comprises: a dielectric layer having a third surface and an opposite fourth surface; a metal layer disposed on the third surface and having a die pad and a plurality of traces, each of the traces comprising a trace body, a bond pad extending to the periphery of the die pad and a trace end opposite to the bond pad; a plurality of metal pillars penetrating the third surface and the fourth surface of the dielectric layer, wherein one ends of the metal pillars exposed from the third surface connect to the die pad and the trace ends, respectively, and the other ends of the metal pillars protrude from the fourth surface, respectively; a semiconductor chip mounted on the die pad; a plurality of bonding wires electrically connecting the semiconductor chip to the bond pads; and an encapsulant covering the semiconductor chip, the bonding wires, the metal layer and the third surface of the dielectric layer.
The semiconductor package structure can further comprise a plurality of metal pads disposed on the ends of the metal pillars protruding from the fourth surface, respectively.
The metal pillars can be made of copper; the dielectric layer can be made of a polymer material comprising an epoxy resin; and the metal layer and the metal pads can be made of one or more selected from the group consisting of Au, Pd, and Ni.
In addition, the contact pad areas are arranged in array to surround the die mounting area, and the bond pads are disposed at the periphery of the die pad, thereby shortening the bonding wires electrically connecting the semiconductor chip and the bond pads.
The present invention further provides a semiconductor package structure, which comprises: a dielectric layer having a third surface and an opposite fourth surface, wherein the third surface has a die mounting area and a plurality of contact pad areas; a plurality of traces disposed on the third surface, each of the traces comprising a trace body, a bond pad extending into the die mounting area and a trace end opposite to the bond pad; a plurality of metal pillars penetrating the third surface and the fourth surface of the dielectric layer, wherein one ends of the metal pillars exposed from the third surface connect to the trace ends, respectively, and the other ends of the metal pillars protrude from the fourth surface, respectively; a semiconductor chip disposed on the bond pads to electrically connect to the traces; and an encapsulant covering the semiconductor chip, the traces and the third surface of the dielectric layer.
According to the present invention, the bond pads and traces formed at the chip mounting side of the dielectric layer shorten the bonding wires and prevent tangling of the bonding wires, thereby improving the electrical connection quality of the package structure. Further, when the semiconductor package structure is soldered to a circuit board, since the metal pillars protrude from the bottom surface of the dielectric layer, it facilitates the formation of stable solder joints between the metal pillars and the circuit board and prevents solder overflow and bridging. In addition, the present invention provides high density and array arranged I/O connections so as to extend the application range of the semiconductor package structure.
The following illustrative embodiments are provided to illustrate the disclosure of the present invention, these and other advantages and effects can be apparent to those in the art after reading this specification.
Referring to
Referring to
Referring to
Referring to
Referring to FIGS. 3E and 3E′, a metal layer 33 is formed in the first open areas 320a, and a plurality of metal pads 34 is formed in the second open areas 320b, respectively. The metal layer 33 comprises a die pad 333 corresponding in position to the die mounting area 301 and a plurality of traces 332. Each of the traces 332 comprises a trace body 3321, a bond pad 3322 extending to the periphery of the die pad 333, and a trace end 3323 opposite to the bond pad 3322 and connected to a corresponding one of the contact pad areas 302. The metal pads 34 correspond in position to the die mounting area 301 and the contact pad areas 302, respectively. Thereafter, the first resist layer 32a and the second resist layer 32b are removed. The metal layer 33 and the metal pads 34 can be formed by an electroplating process and can be made of one or more selected from the group consisting of Au, Pd, and Ni, for example, Au/Pd/Ni/Pd.
Referring to FIG. 3E′, the contact pad areas 302 are arranged in array to surround the die mounting area 301, and the bond pads 3322 are disposed at the periphery of the die pad 333 to surround the die pad 333.
Referring to
Referring to
The present invention further discloses a semiconductor package structure 3, which comprises: a dielectric layer 31 having a third surface 31a and an opposite fourth surface 31b; a metal layer 33 disposed on the third surface 31a and comprising a die pad 333 and a plurality of traces 332, each of the traces 332 comprising a trace body 3321, a bond pad 3322 extending to the periphery of the die pad 333, and a trace end 3323 opposite to the bond pad 3322; a plurality of metal pillars 303 penetrating the third surface 31a and the fourth surface 31b of the dielectric layer 31, wherein one ends of the metal pillars 303 exposed from the third surface 31a are connected to the die pad 333 and the trace ends 3323, and the surfaces of the exposed ends of the metal pillars 303 are flush with the third surface 31a, and the other ends of the metal pillars 303 protrude from the fourth surface 31b; a semiconductor chip 35 mounted on the die pad 333; a plurality of bonding wires 36 electrically connecting the semiconductor chip 35 to the bond pads 3322; and an encapsulant 37 covering the semiconductor chip 35, the bonding wires 36, the metal layer 33 and the third surface 31a of the dielectric layer 31.
The semiconductor package structure 3 further comprises a plurality of metal pads 34 disposed on the ends of the metal pillars 303 protruding from the fourth surface 31b, respectively.
In the semiconductor package structure 3, the metal pillars 303 can be made of copper; the dielectric layer 31 can be made of a polymer material comprising an epoxy resin; the metal layer 33 and the metal pads 34 can be made of one or more selected from the group consisting of Au, Pd, and Ni. Preferably, the metal layer 33 and the metal pads 34 are made of the same material.
Further, referring to FIG. 3E′, the metal pillars 303 are arranged in array to surround the die pad 333, and preferably, the bond pads 3322 are disposed at the periphery of the die pad 333 to surround the die pad 333.
Referring to
Referring to
Referring to
Referring to
Referring to FIGS. 4E and 4E′, a plurality of traces 432 is formed in the first open areas 420a, and a plurality of metal pads 44 is formed in the second open areas 420b. Each of the traces 432 comprises a trace body 4321, a bond pad 4322 extending into the die mounting area 401, and a trace end 4323 opposite to the bond pad 4322 and connected to a corresponding one of the contact pad areas 402. The metal pads 44 correspond in position to the contact pad areas 402, respectively. Thereafter, the first resist layer 42a and the second resist layer 42b are removed. The traces 432 and the metal pads 44 can be formed by an electroplating process and can be made of one or more selected from the group consisting of Au, Pd, and Ni, for example, Au/Pd/Ni/Pd.
Referring to FIG. 4E′, the contact pad areas 402 can be arranged in array to surround the die mounting area 401, and the bond pads 4322 can be arranged in array in the die mounting area 401.
Referring to
Referring to
The present invention further discloses a semiconductor package structure 4, which comprises: a dielectric layer 41 having a third surface 41a and an opposite fourth surface 41b, the third surface 41a having a die mounting area 401 and a plurality of contact pad areas 402; a plurality of traces 432 disposed on the third surface 41a, each of the traces 432 comprising a trace body 4321, a bond pad 4322 extending into the die mounting area 401, and a trace end 4323 opposite to the bond pad 4322; a plurality of metal pillars 403 penetrating the third surface 41a and the fourth surface 41b of the dielectric layer 41, wherein one end of each of the metal pillars 403 is exposed from the third surfaces 41a and connected to the trace ends 4323 of the traces 432, allowing the exposed surfaces of the ends of the metal pillars 403 to be flush with the third surface 41a of the dielectric layer 41, and the other ends of the metal pillars 403 protrude from the fourth surface 41b; a semiconductor chip 45 mounted on the bond pads 4322 and electrically connected to the traces 432; and an encapsulant 47 covering the semiconductor chip 45, the traces 432 and the third surface 41a of the dielectric layer 41.
The semiconductor package structure 4 can further comprise a plurality of metal pads 44 disposed at the ends of the metal pillars 403 protruding from the fourth surface 41b, respectively.
In the semiconductor package structure 4, the metal pillars 403 can be made of copper; the dielectric layer 41 can be made of a polymer material comprising an epoxy resin; the traces 432 and the metal pads 44 can be made of one or more selected from the group consisting of Au, Pd, and Ni. Preferably, the traces 432 and the metal pads 44 are made of the same material.
Further, referring to FIG. 4E′, the metal pillars 403 can be arranged in array to surround the die mounting area 401, and preferably, the bond pads 4322 are annularly arranged within the die mounting area 401.
According to the present invention, the bond pads and traces formed at the chip mounting side of the dielectric layer shorten the bonding wires and prevent tangling of the bonding wires, thereby improving the electrical connection quality of the package structure. Further, when the semiconductor package structure is soldered to a printed circuit board, since the metal pillars protrude from the bottom surface of the dielectric layer, it facilitates the formation of stable solder joints between the metal pillars and the printed circuit board and prevents solder overflow and bridging. In addition, the present invention provides high density and array arranged I/O connections so as to extend the application range of the semiconductor package structure.
The above description of the specific embodiments is intended to illustrate the preferred implementation according to the present invention but is not intended to limit the scope of the present invention. Accordingly, all modifications and variations completed by those with ordinary skill in the art should fall within the scope of present invention defined by the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
98146227 A | Dec 2009 | TW | national |
Number | Name | Date | Kind |
---|---|---|---|
5122860 | Kikuchi et al. | Jun 1992 | A |
5285352 | Pastore et al. | Feb 1994 | A |
5508556 | Lin | Apr 1996 | A |
5942794 | Okumura et al. | Aug 1999 | A |
5953589 | Shim et al. | Sep 1999 | A |
6031292 | Murakami et al. | Feb 2000 | A |
6143981 | Glenn | Nov 2000 | A |
6238952 | Lin | May 2001 | B1 |
6255740 | Tsuji et al. | Jul 2001 | B1 |
6291274 | Oida et al. | Sep 2001 | B1 |
6306685 | Liu et al. | Oct 2001 | B1 |
6376921 | Yoneda et al. | Apr 2002 | B1 |
6399415 | Bayan et al. | Jun 2002 | B1 |
6414385 | Huang et al. | Jul 2002 | B1 |
6420779 | Sharma et al. | Jul 2002 | B1 |
6424024 | Shih et al. | Jul 2002 | B1 |
6498099 | McLellan et al. | Dec 2002 | B1 |
6700188 | Lin | Mar 2004 | B2 |
6777265 | Islam et al. | Aug 2004 | B2 |
6867493 | Hashemi et al. | Mar 2005 | B2 |
7049177 | Fan et al. | May 2006 | B1 |
20020168796 | Shimanuki et al. | Nov 2002 | A1 |
20040097017 | Shimanuki | May 2004 | A1 |
20110001224 | San Antonio et al. | Jan 2011 | A1 |
Number | Date | Country | |
---|---|---|---|
20110156227 A1 | Jun 2011 | US |