Patent Application
20090166873
This invention relates to a semiconductor device package, and more particularly to an inter-connecting structure of package.
The function of chip package includes power distribution, signal distribution, heat dissipation, protection and support. As a semiconductor become more complicated, the traditional package technique, for example lead frame package, flex package, rigid package technique, can't meet the demand of producing smaller chip with high density elements on the chip. In general, array packaging such as Ball Grid Array (BGA) packages provide a high density of interconnects relative to the surface area of the package. Typical BGA packages include a convoluted signal path, giving rise to high impedance and an inefficient thermal path which results in poor thermal dissipation performance. With increasing package density, the spreading of heat generated by the device is increasingly important. In order to meet packaging requirements for newer generations of electronic products, efforts have been expended to create reliable, cost-effective, small, and high-performance packages. Such requirements are, for example, reductions in electrical signal propagation delays, reductions in overall component area, and broader latitude in input/output (I/O) connection pad placement. In order to meet those requirements, a WLP (wafer level package) has been developed, wherein an array of I/O terminals is distributed over the active surface, rather than peripheral-leaded package. Such distribution of terminal may increase the number of I/O terminals and improves the electrical performance of the device. Further, the area occupied by the IC with interconnections when mounted on a printed circuit board is merely the size of the chip, rather than the size of a packaging lead-frame. Thus, the size of the WLP may be made very small. One such type may refer to chip-scale package (CSP).
Improvements in IC packages are driven by industry demands for increased thermal and electrical performance and decreased size and cost of manufacture. In the field of semiconductor devices, the device density is increased and the device dimension is reduced, continuously. The demand for the packaging or interconnecting techniques in such high density devices is also increased to fit the situation mentioned above. The formation of the solder bumps may be carried out by using a solder composite material. Flip-chip technology is well known in the art for electrically connecting a die to a mounting substrate such as a printed wiring board. The active surface of the die is subject to numerous electrical couplings that are usually brought to the edge of the chip. Electrical connections are deposited as terminals on the active surface of a flip-chip. The bumps include solders and/or plastics that make mechanical connections and electrical couplings to a substrate. The solder bumps after RDL have bump high around 50-100 um. The chip is inverted onto a mounting substrate with the bumps aligned to bonding pads on the mounting substrate, as shown in
Furthermore, because conventional package technologies have to divide a dice on a wafer into respective dies and then package the die respectively, therefore, these techniques are time consuming for manufacturing process. Since the chip package technique is highly influenced by the development of integrated circuits, therefore, as the size of electronics has become demanding, so does the package technique. For the reasons mentioned above, the trend of package technique is toward ball grid array (BGA), flip chip (FC-BGA), chip scale package (CSP), Wafer level package (WLP) today. “Wafer level package” is to be understood as meaning that the entire packaging and all the interconnections on the wafer as well as other processing steps are carried out before the singulation (dicing) into chips (dice). Generally, after completion of all assembling processes or packaging processes, individual semiconductor packages are separated from a wafer having a plurality of semiconductor dies. The wafer level package has extremely small dimensions combined with extremely good electrical properties.
The conventional die is only covered by glass and other surfaces of the die are exposed. It is possible to crash the die by external force. The process is also complicated, therefore, the present invention provides a safer scheme to overcome the aforementioned problem and also provide the better device performance.
An object of the present invention is to provide a semiconductor device package (chip assembly) that provides a low cost, high performance and high reliability package.
An interconnecting structure for a semiconductor die assembly comprises: a die having bonding pads on an active surface; a core attached the side wall (edge) of the die by adhesion material; an isolating base adhered on the active surface of the die by adhesion glue; a through silicon via (TSV) open from the back side of the die to expose the bonding pads; a build up layer coupled between the bonding pads to terminal metal pads by the through silicon via; solder balls melted on terminal pads, wherein the terminal pads located on the core and/or the die.
The build up layer includes a first dielectric layer, a re-distribution layer (RDL) and a second dielectric layer on the RDL and the first dielectric layer. RDL is formed by laminated copper foil with patterned etching, or by sputtered metal (Ti/Cu) and patterned E-plated Cu/Ni/Au. The material of the isolating base includes glass, crystal, ceramic, silicon, PI, BT, FR4, FR5, PCB, alloy, organic materials or metal. The material of the core includes PI, BT, FR4, FR5, silicon, glass, ceramic, crystal, PCB, EMC, silicone rubber or resin. Inter-connecting through holes are formed inside the core for coupling signals between on both sides of the die. The material of adhesion material includes elastic material.
An image sensor package structure, comprises an image sensor die having bonding pads and micro lens on an active surface; a core attached the side wall (edge) of the die by adhesion material; a transparent material adhered on the active surface of the die by adhesion glue; a through silicon via (TSV) opened from the back side of the die to expose the bonding pads; at least one RDL coupled to the TSV and conductive bumps connected to the RDL.
A semiconductor device package structure comprises at least one die having bonding pads on an active surface; a core attached the side wall (edge) of the die by adhesion material; an isolation base adhered on the active surface of the die by adhesion glue; a through silicon via (TSV) opened from the back side of the die to expose the bonding pads; at least one RDL coupled to the TSV and conductive bumps connected to the RDL.
A multi-chips package structure, comprising: a lower package includes a first die having first bonding pads on a first active surface; a first core (substrate) having inter-connecting through holes with contact pads on both side to attach the side wall (edge) of the first die by a first adhesion material; a first through silicon via (TSV) opened from the back side of the first die to expose the first bonding pads; a first RDL coupled to the first bonding pads and contact pads; and an upper package includes a second die having second bonding pads on a second active surface; a second core attached the side wall (edge) of the second die by a second adhesion material; a second through silicon via (TSV) opened from the back side of the second die to expose the second bonding pads; a second RDL coupled to the second bonding pads; an isolation based formed on the top of upper package; wherein the lower package and the upper package is coupled by interconnecting solder connected between the second RDL and upper contact of the lower package.
A multi-chips package structure, comprises a lower package includes a first die having first bonding pads on a first active surface; a first core having inter-connecting through holes with contact pads on both side to attach the side wall (edge) of the first die by a first adhesion material; a first through silicon via (TSV) opened from the back side of the first die to expose the first bonding pads; a first RDL coupled to the first TSV; and an upper package includes a second die having second bonding pads on a second active surface; a second core attached the side wall (edge) of the second die by a second adhesion material; a second through silicon via (TSV) opened from the back side of the second die to expose the second bonding pads; a second RDL coupled to the second bonding pads; wherein the lower package and the upper package is coupled by at least one isolation based formed there-between, thereby constructing face-to-face (from the active surface of die point of view) configuration; pluralities of CNC through holes penetrating from the first core to the second core, and coupling the first RDL to second RDL, and conductive metal fill into the CNC through holes.
a and 3b illustrate a cross section view showing semiconductor chip assembly in accordance with embodiment of the present invention.
a and 7b illustrate a cross section view showing inter-connecting structure in accordance with embodiment of the present invention.
The invention will now be described in greater detail with preferred embodiments of the invention and illustrations attached. Nevertheless, it should be recognized that the preferred embodiments of the invention is only for illustrating. Besides the preferred embodiment mentioned here, present invention can be practiced in a wide range of other embodiments besides those explicitly described, and the scope of the present invention is expressly not limited expect as specified in the accompanying Claims.
The present invention discloses a semiconductor device package structure. The present invention provide a semiconductor chip assembly which includes chip, conductive trace and metal inter-connecting as shown in
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Advantages: the package size is independent to the chip size and may keep the same ball pitch with the one of the chip. It offers better reliability in via inter-connecting. The chip's active surface is protected during process and it provides better electrical isolation from top surface. Thinner chip is better for reliability and it provides easy processes to form the thinner chips. Side-by-side and stacking package maybe provided easily, it is also easy to fan-out the terminal pins.
In order to achieve the scheme, the essential conditions under the bonding pads include: no active circuitry permitted under the bonding pads, it needs the insulating layer structure and insulating layer materials to isolate the RDL to contact with silicon itself due to silicon itself is semi-conductor. The pitch of bonding pads should be considered and alignment key is necessary from upper surface to lower surface.
The method of forming a semiconductor die assembly comprises: bonding an isolating base having adhesion material on the active surface side of a wafer and curing the adhesion material that is mounted on a tape and lapping the back side of the wafer to desired thickness, it maybe from 25 um to 100 um, followed by dicing the wafer with isolating base together, then, picking and placing the die with the isolating base on a die placement tools with back side (Via Holes) stuck on the die placement tools by pattern glues. Next, core (or substrate) is placed onto the die placement tools, adhesion materials is filled into gap between the edge of the die and side wall of the core, thereby forming a panel; the adhesive material is cured after filling the adhesive material, followed by separating the panel from the die placement tools. The next step is to form TSV within the die. Seed metal is sputtered and PR is coated to define a trace pattern, followed by forming RDL to couple the TSV and forming solder balls.
The method further comprises a step of drilling the wafer by laser drill, dry etching or wet etching (with pattern) through back side in order to form via contact after lapping the wafer. Alternatively, it could be done after curing the adhesive material. It also further comprises a step of curing the adhesive material after filling the adhesive material.
Typically, under bump metallurgy (UBM) is formed before the formation of the ball as the barrier and adhesion for preventing the issue between the ball and the ball pad.
Although preferred embodiments of the present invention have been described, it will be understood by those skilled in the art that the present invention should not be limited to the described preferred embodiment. Rather, various changes and modifications can be made within the spirit and scope of the present invention, as defined by the following Claims.
