摘要:
A method is proposed for bonding a BGA (Ball Grid Array) package to a circuit board without causing the collapsing of the BGA package against the circuit board. The proposed method is characterized in the use of two groups of solder balls of different reflow collapse degrees, which are arranged in an interspersed manner among each other in the ball grid array. In one embodiment, the first group of solder balls are homogenously made of a solder material of a specific melting point; and the second group of solder balls each include an outer portion and a core portion, with the outer portion having substantially the same melting point as the first group of solder balls, and the core portion being greater in melting point than the outer portion. In another embodiment, the second group of solder balls are greater in melting point than the first group of solder balls. During the solder-reflow process, when the first group of solder balls are entirely melted, the second group of solder balls are only partly melted or entirely unmelted and thus are capable of providing a solid support to the BGA package to prevent the collapsing of BGA package against circuit board.
摘要:
A method of fabricating a BGA (Ball Grid Array) IC package of the type having an encapsulating body is proposed, which allows the BGA IC package to be manufactured without having to use conventional organic substrate and encapsulating-body mold having cavity, so that the manufacture process can be more cost-effective to carry out than the prior art. The proposed method is characterized in the use of a copper piece which is selectively removed to form an encapsulating-body cavity for the forming of an encapsulating body therein. The proposed method requires no use of mold with cavity for the forming of the encapsulating body, allowing the same mold to be used for the fabrication of various BGA IC packages of different sizes. Moreover, the proposed method allows fan-in design as well as fan-out design, thus allowing the number of I/O ports to be increased while making the overall package configuration compact in size, and also allows the implantation of the electrically-conductive balls to be easier to carry out and more precisely controlled than the prior art, making the ball implantation more assured in quality than the prior art. Therefore, the proposed method is more advantageous and cost-effective to use than the prior art.
摘要:
A flash-free mold structure is designed for use in the molding of an encapsulant for encapsulating a semiconductor die. The flash-free mold structure includes a first molding piece and a second molding piece. The second molding piece is formed with a resin passage for an encapsulating material to flow therethrough during molding process. It is a characteristic feature of this flash-free mold structure that a cutaway portion, which can be either an one-step cutaway portion or a multi-step cutaway portion, is formed at the rim of the resin passage. The cutaway portion is dimensioned significantly smaller than the resin passage for the retarding the flow speed of the encapsulating material from the resin passage into the cutaway portion during the molding process, thereby preventing the encapsulating material from entering the fissure in the junction between the first and second molding pieces. The resin passage can be either a cull, a runner, or a subrunner defined by the first and second molding pieces. With this flash-free mold structure, the IC packaging quality can be assured and fabrication tools can be prevented from contamination.
摘要:
An EMI shielding package structure includes a substrate unit having a first surface with a die mounting area and a second surfaces opposite to the first surface, metallic pillars formed on the first surface, a chip mounted on and electrically connected to the die-mounting area, an encapsulant covering the chip and the first surface while exposing a portion of each of the metallic pillars from the encapsulant, and a shielding film enclosing the encapsulant and electrically connecting to the metallic pillars. A fabrication method of the above structure by two cutting processes is further provided. The first cutting process forms grooves by cutting the encapsulant. After a shielding film is formed in the grooves and electrically connected to the metallic pillars, the complete package structure is formed by the second cutting process, thereby simplifying the fabrication process while overcoming inferior grounding of the shielding film as encountered in prior techniques.
摘要:
A package structure having an MEMS element is provided, which includes: a protection layer having openings formed therein; conductors formed in the openings, respectively; conductive pads formed on the protection layer and the conductors; a MEMS chip disposed on the conductive pads; and an encapsulant formed on the protection layer for encapsulating the MEMS chip. By disposing the MEMS chip directly on the protection layer to dispense with the need for a carrier, such as a wafer or a circuit board that would undesirably add to the thickness, the present invention reduces the overall thickness of the package to thereby achieve miniaturization.
摘要:
A heat dissipating semiconductor package and a fabrication method thereof are provided. A semiconductor chip is mounted on a chip carrier. A heat sink is mounted on the chip, and includes an insulating core layer, a thin metallic layer formed on each of an upper surface and a lower surface of the insulating core layer and a thermal via hole formed in the insulating core layer. A molding process is performed to encapsulate the chip and the heat sink with an encapsulant to form a package unit. A singulation process is performed to peripherally cut the package unit. A part of the encapsulant above the thin metallic layer on the upper surface of the heat sink is removed, such that the thin metallic layer on the upper surface of the heat sink is exposed, and heat generated by the chip can be dissipated through the heat sink.
摘要:
A semiconductor package structure includes: a dielectric layer; a metal layer disposed on the dielectric layer and having a die pad and traces, the traces each including a trace body, a bond pad extending to the periphery of the die pad, and an opposite trace end; metal pillars penetrating the dielectric layer with one ends thereof connecting to the die pad and the trace ends while the other ends thereof protruding from the dielectric layer; a semiconductor chip mounted on the die pad and electrically connected to the bond pads through bonding wires; and an encapsulant covering the semiconductor chip, the bonding wires, the metal layer, and the dielectric layer. The invention is characterized by disposing traces with bond pads close to the die pad to shorten bonding wires and forming metal pillars protruding from the dielectric layer to avoid solder bridging encountered in prior techniques.
摘要:
Proposed is a driver having dead-time compensation function. The driver having dead-time compensation function generates an output voltage according to a voltage command and a frequency command. The driver includes an inverter, an output current detector and a control unit. The inverter receives a DC voltage and operates with a pulse width modulation mode so that the driver outputs the output voltage and an output current. The output current detector detects the current value of the output current to generate a output current detecting signal. The control unit outputs a switching control signal to inverter according to the voltage command and the frequency command. The control unit corrects a reference command according to dead-time and the output current detecting signal related to the output current so that amplitude and waveform smoothness of the output voltage and the output current are compensated.
摘要:
A semiconductor package having electrical connecting structures includes: a conductive layer having a die pad and traces surrounding the die pad; a chip; bonding wires; an encapsulant with a plurality of cavities having a depth greater than the thickness of the die pad and traces for embedding the die pad and the traces therein, and the cavities exposing the die pad and the traces; a solder mask layer formed in the cavities and having a plurality of openings for exposing the trace ends and a portion of the die pad; and solder balls formed in the openings and electrically connected to the trace ends. Engaging the solder mask layer with the encapsulant enhances adhesion strength of the solder mask layer so as to prolong the moisture permeation path and enhance package reliability.
摘要:
Proposed is a package structure having a micro-electromechanical (MEMS) element, including a chip having a plurality of electrical connecting pads and a MEMS element formed thereon; a lid disposed on the chip for covering the MEMS element; a stud bump disposed on each of the electrical connecting pads; an encapsulant formed on the chip with part of the stud bumps being exposed from the encapsulant; and a metal conductive layer formed on the encapsulant and connected to the stud bumps. The invention is characterized by completing the packaging process on the wafer directly to enable thinner and cheaper package structures to be fabricated within less time. This invention further provides a method for fabricating the package structure as described above.