Patent Publication Number: US-2019189494-A1

Title: Package structure and manufacturing method thereof

Description:
BACKGROUND OF THE INVENTION 
     Field of Invention 
     The present invention relates to a manufacturing method thereof, and more particularly, to a manufacturing method of package structure. 
     Description of Related Art 
     Generally, wafer level or panel 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 such as wire bonding, die bonding or molding, are carried out before the singulation by dicing into a plurality of semiconductor dies. However, it requires large-scale equipment to perform such processes in wafer or panel level format. Further, it requires very heavy capital investment for such large-scale equipment, while such capital investment does not provide cost benefits. Therefore, how to accomplish the processing steps using existing equipment to minimize equipment costs and overall manufacturing costs has become a challenge to researchers in the field. 
     SUMMARY OF THE INVENTION 
     The invention provides a manufacturing method of a package structure, which increases the production and provides processing stability. 
     The invention provides a manufacturing method of a package structure. The method includes the following steps. A package panel is provided. The package panel includes a first encapsulation, a plurality of first integrated circuit components and a plurality of redistribution circuit patterns electrically connected to the first integrated circuit components, the first integrated circuit components are encapsulated by the first encapsulation, and the redistribution circuit patterns are distributed on the first encapsulation and the first integrated circuit components. The first encapsulation of the package panel is cut to form a plurality of singulated package strips. Each of the singulated package strips includes a first singulated encapsulation, one of the redistribution circuit patterns and at least one of the first integrated circuit components encapsulated by the first singulated encapsulation. One of the singulated package strips is attached onto an attachment region of a substrate. The substrate includes at least one tooling hole distributed outside of the attachment region. A package process is performed over the singulated package strip attached onto the substrate with the substrate affixed through the at least one tooling hole to form the package structure. 
     The invention provides a manufacturing method of a package structure. The method includes the following steps. A package panel is provided in a first process chamber. The package panel includes a first encapsulation, a plurality of first integrated circuit components and a plurality of redistribution circuit patterns electrically connected to the first integrated circuit components, the first integrated circuit components are encapsulated by the first encapsulation, and the redistribution circuit patterns are distributed on the first encapsulation and the first integrated circuit components. The first encapsulation of the package panel is cut to form a plurality of singulated package strips in the first process chamber. Each of the singulated package strips includes a first singulated encapsulation, one of the redistribution circuit patterns and at least one of the first integrated circuit components encapsulated by the first singulated encapsulation. The singulated package strips are transferred to a second process chamber. At least one holding fixture is configured in the second process chamber. One of the singulated package strips is attached onto an attachment region of a substrate in the second process chamber. The substrate includes at least one tooling hole distributed outside of the attachment region. The substrate is affixed by the at least one holding fixture in the second process chamber. The at least one holding fixture corresponding to the at least one tooling hole of the substrate. A package process is performed over the singulated package strip attached onto the substrate to form the package structure in the second process chamber. 
     Based on the above, the package panel is cut to form the singulated package strips before the package process so as to avoid using large-scale equipment to perform such package process. As such, existing equipment may be leveraged with changes and compatible to the manufacturing process flow and also it maintains a stable manufacturing process which can be cost optimized according to the applications being implemented in the package. 
     To make the above features and advantages of the present invention more comprehensible, several embodiments accompanied with drawings are described in detail as follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
         FIG. 1  is a schematic cross-sectional view illustrating a manufacturing method of a package structure according to an embodiment of the invention. 
         FIG. 2A  is a schematic top view illustrating a manufacturing method of a package structure according to an embodiment of the invention. 
         FIG. 2B  is a schematic cross-sectional view illustrating along the line A-A of the manufacturing method of the package structure in  FIG. 2A . 
         FIG. 3A  is schematic top view illustrating a manufacturing method of a package structure according to an embodiment of the invention. 
         FIG. 3B  is a schematic cross-sectional view along the line A-A of the manufacturing method of the package structure in  FIG. 3A . 
         FIG. 3C  to  FIG. 3D  are schematic cross-sectional views illustrating a manufacturing method of a package structure according to an embodiment of the invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. 
       FIG. 1  is a schematic cross-sectional view illustrating a manufacturing method of a package structure according to an embodiment of the invention. Referring to  FIG. 1 ,  FIG. 1  shows a portion of a package at an intermediate stage of manufacturing process. A plurality of redistribution circuit patterns  120  is formed over a carrier  110   a . The carrier  110   a  is, for example, a glass substrate or other suitable substrate material, which is not limited thereto as long as the material is able to withstand the subsequent processes while carrying the package formed thereon. The redistribution circuit patterns  120  include a first surface  120   a  and a second surface  120   b  opposite to the first surface  120   a . The second surface  120   b  faces towards and is adhered to the carrier  110   a . A plurality of conductive terminals  150  are formed over the first surface  120   a  of the redistribution circuit patterns  120  by a placement process and/or a reflow process so as to electrically connect to the redistribution circuit patterns  120 . For example, the conductive terminals  150  may be conductive bumps, conductive pillars or other possible forms and shapes, which is not limited thereto. 
     In the present embodiment, a plurality of first integrated circuit components  130  are formed over the first surface  120   a  of the redistribution circuit patterns  120  with the conductive terminals  150  surrounding the first integrated circuit components  130 . Moreover, the first integrated circuit component  130  has a rear surface  130   a  and an active surface  130   b  opposite to the rear surface  130   a . The active surface  130   b  of the first integrated circuit components  130  are electrically connected to the redistribution circuit patterns  120  by bumps  130   c . For instance, the first integrated circuit components  130  may be an ASIC (Application-Specific Integrated Circuit) or other suitable active devices, which is not limited thereto. In some embodiments, the chip bonding process of the first integrated circuit components  130  is performed prior to the formation of the conductive terminals  150 . In some alternative embodiments, the chip bonding process of the first integrated circuit components  130  is performed after the formation of the conductive terminals  150 . In addition, a first encapsulation  140  is formed over the first surface  120   a  of the redistribution circuit patterns  120  to encapsulate the first integrated circuit components  130  and the conductive terminals  150 . For example, the first encapsulation  140  may be a molding compound formed by molding processes. However, in some embodiments, the first encapsulation  140  may be formed by an insulating material such as epoxy or other suitable insulating resins, which is not limited thereto. 
     Furthermore, the first encapsulation  140  may be grinded by a chemical mechanical polishing (CMP) or other suitable grinding technique in order to expose the conductive terminals  150  and reduce the overall thickness of the package structure  400  (shown in  FIG. 3D ). In one embodiment, after the grinding process, the rear surface  130   a  of the first integrated circuit components  130  and the conductive terminals  150  may be exposed simultaneously. Moreover, the exposed rear surface  130   a  of the integrated circuit components  130  and the exposed surface of the conductive terminals  150  may be aligned after grinding. In another embodiment, after the grinding process, the conductive terminals  150  may be exposed while the rear surface  130   a  of the first integrated circuit components  130  may be covered by the first encapsulation  140 . Moreover, the thickness of the first integrated circuit components  130  may be, for instance, less than the diameter (or thickness) of the grinded conductive terminals  150 . In some embodiment, the grinding process may be omitted depending on the design requirement. Next, the second surface  120   b  of the redistribution circuit patterns  120  is de-bonded from the carrier  110   a  by physical treatment (e.g. laser lift-off process) or chemical treatment (e.g. chemical etching). In one embodiment, the de-bonding layer (not shown) may be disposed between the second surface  120   b  of the redistribution circuit patterns  120  and the carrier  100   a . In other words, the de-bonding layer (not shown) may be formed on the carrier  100   a  prior to the formation of the redistribution circuit patterns  120 . As such, the de-bonding between the redistribution circuit patterns  120  and the carrier  110   a  may be performed by peeling off the de-bonding layer from the redistribution circuit patterns  120  or the carrier  100   a.    
       FIG. 2A  is a schematic top view illustrating a manufacturing method of a package structure according to an embodiment of the invention, and  FIG. 2B  is a schematic cross-sectional view illustrating along the line A-A of the manufacturing method of the package structure in  FIG. 2A . Referring to  FIG. 2A  and  FIG. 2B , the structure illustrated in  FIG. 1  is flipped upside down and disposed on the carrier  110   b  to form the package panel  200  after de-bonding the second surface  120   b  of the redistribution circuit patterns  120  from the carrier  110   a . Therefore, the package panel  200  is provided with the second surface  120   b  facing upward. It should be noted that the first integrated circuit components  130  may be arranged in an array on the carrier  110   b.    
       FIG. 3A  is schematic top view illustrating a manufacturing method of a package structure according to an embodiment of the invention.  FIG. 3B  is a schematic cross-sectional view along the line A-A of the manufacturing method of the package structure in  FIG. 3A . Referring to  FIG. 3A  and  FIG. 3B , the package panel  200  sealed with the first encapsulation  140  is cut along the scribe line into strip level to form a plurality of singulated package strips  300 . For example, the cutting process in a two-dimensional array, such as a set of row cuts and column cuts may be performed by rotating blade or laser beam, which is not limited thereto. In addition, each of the singulated package strips  300  includes a first singulated encapsulation  240 , one of the redistribution circuit patterns  120  and at least one of the first integrated circuit components  130  encapsulated by the first singulated encapsulation  240 . The aforementioned processes may be performed in a first process chamber (not illustrated) with large-scale equipment. However, after the cutting process, the singulated package strips  300  may be transferred to a second process chamber (not illustrated) with relatively small-scale equipment in order to perform the following processes. Moreover, the first process chamber and the second process chamber may be isolated or combined, which is not limited thereto. 
     For instance, the equipment in the first process chamber may perform the package process in a wafer level or a panel level, while the equipment in the second process chamber may perform the package process in a strip level or a block level for efficient assembly. As such, the existing assembly technologies and the existing equipment may be compatible to perform the subsequent package process instead of performing the most package process or even the entire package process with large-scale equipment. 
     The singulated package strip  300  is attached onto an attachment region  310   a  of a substrate  310 . The substrate  310  is, for example, a glass or other suitable material. It should be noted that the shape, material and thickness of the substrate construe no limitation in the invention as long the substrate  310  is able to withstand the subsequent processes while carrying the package structure formed thereon. In one embodiment, an adhesive layer  330  is at least formed on the attachment region  310   a  of the substrate  310  to enhance the adhesion between the singulated package strips  300  and the substrate  310 . The formation of the adhesive layer  330  on the substrate  310  may be, for instance, performed prior to or after the transferring process of the singulated package strips  300 . In one embodiment, the formation of the adhesive layer  330  on the substrate  310  is performed before attaching one of the singulated package strips  300  onto the attachment region  310   a  of the substrate  310 . The adhesive layer  330  may be formed by, for example, attaching a film, applying a paste or glue, or other suitable material and manner, which is not limited thereto. 
     In the present embodiment, the area of the substrate  310  is greater than the area of the singulated package strip  300 . In addition, the substrate  310  includes at least one tooling hole  320  distributed outside of the attachment region  310   a . In other words, the tooling holes  320  may be distributed at a periphery area surrounding the attachment region  310   a . The tooling hole  320  may be utilized for alignment or affixation of the substrate  310  for the subsequent processes. It should be noted that although three tooling holes  320  are shown in  FIG. 3A , the amount of tooling holes  320  is not limited thereto. In one embodiment, the tooling holes  320  may be located on the different planes with the adhesive layer  330 . For instance, the tooling holes  320  may be disposed on the sidewalls of the substrate  310 . The configuration of the tooling holes is not limited thereto. 
     For example, the process equipment in the second chamber may perform the subsequent processes by positioning the tooling holes  320  so as to align the location of the singulated package strips  300  on the substrate  310 . Furthermore, for the stability of the subsequent processes, the substrate  310  may be affixed by the tooling holes  320  fixed with a holding fixture (not illustrated). The holding fixture provides a mechanical support for the substrate  310 . For instance, the holding fixture may be configured in the second process chamber or to the transferring equipment so as to ensure performing the processes in a stable state. The holding fixture may be positioned at the tooling holes  320  of the substrate  310 . For example, the holding fixture may include a plurality of pins which corresponds to the tooling holes  320 . When transferring or processing the substrate  310  thereon, the pins of the holding fixture may be inserted into the tooling holes to avoid any undesired movement or shift of the substrate  310 . In one embodiment, the holding fixture may be a vacuum fixture or a clamp, but is not limited thereto as long as it may affix the substrate  310  without causing the damage of the singulated package strips  300  during transferring or processing. 
       FIG. 3C  to  FIG. 3D  are schematic cross-sectional views illustrating a manufacturing method of a package structure according to an embodiment of the invention. Referring to  FIG. 3C  and  FIG. 3D , a plurality of passive components  340  are formed over the second surface  120   b  of the redistribution circuit patterns  120 . In addition, the passive components  340  may be, for instance, disposed corresponding to the conductive terminals  150 . It should be noted that the passive components  340  may be disposed in any manner as long as the passive components  340  are electrically connected to the redistribution circuit patterns  120 . The passive components  340  may be, for instance, capacitors, resistors, inductors and so on. Moreover, at least one second integrated circuit component  350  is also formed over the second surface  120   b  of the redistribution circuit patterns  120  by bonding process. For example, the second integrated circuit component  350  may be memory devices such as NAND flash die or other suitable chips, which is not limited thereto. In addition, the second integrated circuit component  350  is electrically connected to the redistribution circuit patterns  120  through wires by wire bonding process. That is to say, the second integrated circuit component  350  is electrically connected to the conductive terminals  150  by wires. In some embodiments, the bonding process of the passive components  340  is performed prior to the bonding process of the second integrated circuit component  350 . In some alternative embodiments, the bonding process of the passive components  340  is performed after the bonding process of the second integrated circuit component  350 . However, the sequential order of bonding process between the passive components  340  and the second integrated circuit component  350  construe no limitation in the invention. 
     In the present embodiment, a second encapsulation  360  is formed to encapsulate the passive components  340  and the second integrated circuit component  350 . Similar to the first encapsulation  140 , the second encapsulation  360  may be also formed by a molding compound or an insulating material by molding process. It may be understood that other components may also be assembled onto the substrate  310 , such as when packages in system are being fabricated. Subsequently, a singulation process is performed on the singulated package strips  300  so as to obtain a plurality of package structures  400 . Moreover, each of the package structures  400  includes a second singulated encapsulation  360   a , the passive components  340  and at least one second integrated circuit component  350 . In addition, the second integrated circuit component  350  is electrically connected to the redistribution circuit patterns  120  of the singulated package strip  300 . The passive components  340  and the second integrated circuit components  350  are encapsulated by the second singulated encapsulation  360   a . Furthermore, the singulation process may be, for example, cutting with rotating blade or laser beam or other suitable technique, which is not limited thereto. 
     Referring to  FIG. 3D , after the singulation process described above, the adhesive layer  330  and the substrate  310  are removed from the package structures  400 . For instance, the external energy (for example, UV laser, visible light, or heat) may be applied to the adhesive layer  330 , so as to allow the package structures  400  to de-bond from the substrate  310 . However, other suitable technique depending on the structure and material of the adhesive layer  330  may be applied, which is not limited thereto. In one embodiment, after removing the adhesive layer  330 , an epoxy mold compound (EMC) layer may be further formed over the rear surface  130   a  in order to encapsulate the first integrated circuit components  130 . Moreover, the substrate  310  with the tooling holes  320  may be reused after de-bonding from the package structures  400  so as to reduce the packaging costs. 
     Based on the foregoing, the package panel is cut to form the singulated package strips before the package process so as to avoid using large-scale equipment to perforin such package process. In addition, the package process is more efficient in strip format. Moreover, the package process performed on the substrate with fixed the tooling hole may ensure the stability of the manufacturing process. As such, existing equipment may be leveraged with changes and compatible to the manufacturing process flow and also it maintains a stable manufacturing process as well as improvement of the product yield. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.