Molding apparatus and method for manufacturing electronic packages
By setting a flow control structure on the sidewall of the molding cavity of the molding equipment, the problems of voids and incomplete molding in high-density packaging are solved, thereby improving the quality and yield of packaging.
Patent Information
- Application Number
- CN202410861168.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-28
- Publication Date
- 2025-12-30
AI Technical Summary
Existing molds and bushings are prone to voids and incomplete molding problems in high-density packaging, leading to electrostatic discharge and short circuit defects, which affect the yield of high-density packaging.
Molding equipment with flow control structure is used. By setting the flow control structure on or near the side wall of the molding cavity, the flow rate of the molding fluid near the side wall is reduced, thus avoiding non-uniform distribution of the fluid flow rate.
It effectively reduces or avoids voids and incomplete mold defects, improving the yield and quality of high-density packaging.
Smart Images
Figure CN121237658A_ABST
Abstract
Description
Technical Field
[0001] This application generally relates to semiconductor technology, and more specifically, to a molding apparatus and a method for manufacturing electronic packages. Background Technology
[0002] Recently, with the increasing demand for high-performance, low-cost, and miniaturized electronic devices, more and more electronic components and functions are being integrated into a single electronic package. High-density packaging is an advanced technology that integrates various functions, such as communication, audio / video, computing, and / or the like, into a single electronic package. To implement high-density packaged units, interconnect structures such as interposers (e-bars, Cu pillars) and through-mold via (TMV) structures can be applied.
[0003] Figure 1A and 1B The diagram shows a top view and a cross-sectional view of a normal density packaged unit 10, while... Figure 1C and 1D A top view and a cross-sectional view of the high-density packaging unit 20 are shown. (See attached image.) Figures 1A to 1D As shown in the figure, with Figure 1A and 1B Compared to the normal density packaging unit 10 shown in the figure, Figure 1C and 1D The electronic package 10 shown requires placement in a high-density array at a higher density, and various interconnect structures 22 can be mounted close to the edge regions of the package unit 20 for interconnection purposes. Therefore, conventional mold design for normal-density package units 10 may not be suitable for the strips of high-density package units 20, where the minimum distance between the sidewall of the mold cavity of the mold and the corresponding edge of the electronic package in the array is approximately 1.535 mm. In particular, if conventional molds are used, voids and incomplete molds may occur in the high-density array.
[0004] Therefore, there is a need for improved molds and bushings for high-density arrays. Summary of the Invention
[0005] The objective of this application is to provide a molding apparatus and a method for manufacturing electronic packages that avoids the problems of voids and incomplete molding.
[0006] According to one aspect of this application, a molding apparatus is provided. The molding apparatus includes: a top mold sleeve; and a bottom mold sleeve that mates with the top mold sleeve, wherein the top mold sleeve and the bottom mold sleeve together define a molding cavity for receiving an encapsulation strip, and the molding cavity includes a flow inlet and a flow outlet, the flow inlet being configured to receive molding fluid, and the flow outlet being configured to output molding fluid after the molding fluid has flowed through the molding cavity and past the encapsulation strip in a flow direction generally from the flow inlet to the flow outlet, wherein the molding cavity further includes a flow control structure located at or near two sidewalls of the molding cavity relative to the flow direction to reduce the flow velocity of the molding fluid near the two sidewalls.
[0007] According to another aspect of this application, a method for manufacturing an electronic package is provided. The method includes: placing a package strip in a molding cavity having a flow inlet, a flow outlet, a plurality of sidewalls relative to a flow direction from the flow inlet to the flow outlet, and a flow control structure located at or near the plurality of sidewalls; receiving molding fluid at the flow inlet; guiding the molding fluid from the flow inlet toward the flow outlet of the molding cavity such that, as the molding fluid flows through the package strip, the flow control structure reduces the flow rate of the molding fluid near the plurality of sidewalls; and discharging the molding fluid at the flow outlet.
[0008] It should be understood that both the foregoing general description and the following detailed description are illustrative and explanatory only, and do not limit the invention. Furthermore, the accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with this specification, serve to explain the principles of the invention. Attached Figure Description
[0009] The accompanying drawings referenced herein form part of this specification. The features shown in the drawings are only illustrative of some embodiments of this application, and not all embodiments of this application, unless the detailed description clearly indicates otherwise, and the reader of this specification should not infer the contrary.
[0010] Figure 1A and 1B The diagram shows a top view and a cross-sectional view of a normal-density packaged cell, while... Figure 1C and 1D The diagram shows a top view and a cross-sectional view of a high-density packaging cell.
[0011] Figures 2A to 2C The simulation results of mold flow for normal density encapsulation strips in a conventional mold die are shown under different test conditions.
[0012] Figure 3A and 3B This further illustrates the incomplete die-cutting problem of high-density packaging strips.
[0013] Figure 4A , 4B Figures 4C and 4C illustrate a molding apparatus according to an embodiment of this application.
[0014] Figure 5A and 5B A molding apparatus according to another embodiment of this application is shown.
[0015] Figure 6A and 6B Showing the target based on Figures 4A to 4C and Figures 5A to 5B The simulation results of two mold flows for high-density encapsulation strips in the molding cavity of the two embodiments shown in the figure.
[0016] Figure 7 A flowchart illustrating a method for manufacturing an electronic package according to an embodiment of this application is shown.
[0017] Throughout the accompanying drawings, the same reference numerals will be used to refer to the same or similar parts. Detailed Implementation
[0018] The following detailed description of exemplary embodiments of this application refers to the accompanying drawings, which form a part of the description. The drawings illustrate specific exemplary embodiments in which this application may be practiced. The detailed description, including the drawings, describes these embodiments in sufficient detail to enable those skilled in the art to practice this application. Those skilled in the art can further utilize other embodiments of this application and make logical, mechanical, and other changes without departing from the spirit or scope of this application. Therefore, the reader of the following detailed description should not interpret the description in a limiting sense, and the scope of the embodiments of this application is defined only by the appended claims.
[0019] In this application, unless otherwise expressly stated, the use of the singular includes the plural form. In this application, unless otherwise stated, the use of “or” means “and / or”. Furthermore, the use of the term “including” and other forms such as “includes” and “included” is not restrictive. Additionally, unless otherwise expressly stated, terms such as “element” or “component” cover both elements and components comprising one unit and elements and components comprising more than one sub-unit. Furthermore, the section headings used herein are for organizational purposes only and should not be construed as limiting the subject matter described.
[0020] As used herein, for ease of description, spatial relative terms such as “below,” “under,” “above,” “above,” “on,” “upper,” “lower,” “left,” “right,” “vertical,” “horizontal,” “side,” etc., may be used to describe the relationship between one element or feature and another element (or feature) or feature (or feature) as shown in the accompanying drawings. In addition to the orientations depicted in the accompanying drawings, the spatial relative terms are intended to cover different orientations of the device in use or operation. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptive terms used herein shall be interpreted accordingly. It should be understood that when an element is referred to as “connected to” or “coupled to” another element, the element may be directly connected to or coupled to the other element, or there may be intermediate elements present.
[0021] As previously mentioned, encapsulation strips (especially high-density encapsulation strips) may suffer from voids and incomplete mold problems. The inventors of this application have conducted various experiments to investigate the causes of these problems. The inventors unexpectedly discovered that the mold flow in the mold sleeve used for encapsulating strips caused the above problems.
[0022] Figures 2A to 2C The simulation results of mold flow for normal density encapsulation strips in a standard mold sleeve are shown under different test conditions. Specifically, Figure 2A The simulation results are shown under the condition that the distance between the sidewall of the molding cavity and the corresponding edge of the electronic package strip is 4.059 mm. Figure 2B The simulation results are shown under the condition that the distance between the sidewall and the corresponding edge of the electronic packaging strip is 2.000 mm. Figure 2C The simulation results are shown under the condition that the distance between the sidewall and the corresponding edge of the electronic package strip is 1.600 mm. For example... Figures 2A to 2C As shown in the figure, the molding fluid flows on the surface of the encapsulation strip and gradually occupies most of the surface.
[0023] Specifically, such as from Figures 2A to 2CThe simulation results shown indicate that the molding fluid in the molding cavity exhibits a U-shaped leading edge, meaning that the molding fluid can have a higher velocity near the sidewalls of the molding cavity compared to its velocity at the center. This non-uniform velocity of the molding fluid in the molding cavity can create significant voids later in the molding process. This is not a major issue if the molding process is used for molding normal-density package strips. However, if a conventional mold is directly applied to the molding process of high-density package strips, this incomplete molding fluid (such as epoxy molding compounds) may not fully cover the interconnect structures mounted on the high-density package array or strip, such as interposers (electron rods, Cu pillars) and through-mold (TMV) structures. These voids and incomplete mold issues can lead to significant defects such as electrostatic discharge (ESD) or short-circuit defects, which significantly reduce the yield of high-density packages.
[0024] Figure 3A and 3B This further illustrates the incomplete die-cutting issue of the high-density packaging strip 30. Specifically, Figure 3A A top view of the high-density packaging strip 30 is shown, and Figure 3B The diagram shows a cross-sectional view of the high-density packaging strip 30 along line BB'.
[0025] like Figure 3A As shown, when molding fluid is injected into the mold sleeve in the flow direction A from the flow inlet to the flow outlet to seal various electronic packages of the high-density packaging strip 30, the molding fluid can flow faster in the edge region of the mold sleeve. That is, the portion 32 of the molding fluid flowing in the edge region can reach the flow outlet earlier than the other portion 34 of the molding fluid flowing in the central region. Therefore, air in the central region may be trapped in the molding fluid and cannot be discharged from the molding fluid through the flow outlet, thus creating a void 36 near the flow outlet of the mold sleeve.
[0026] To address the aforementioned problems, the inventors of this application have conceived of a novel molding apparatus with a flow control structure to avoid incomplete mold problems. The flow control structure can be located on or near the sidewall of the molding cavity of the molding apparatus to reduce or eliminate non-uniform distribution of the molding fluid velocity during the molding process. In this way, air may not be trapped in the molding fluid in the later stages of the molding process, and therefore unwanted voids will not be generated in the resulting mold cap.
[0027] Figure 4A , 4B Figures 4C and 4C illustrate a molding apparatus 400 according to an embodiment of this application. Specifically, Figure 4A This is a top view of molding equipment 400, and Figure 4B and 4CFor part of molding equipment 400 along Figure 4A Cross-sectional views of lines BB and CC in the diagram.
[0028] like Figure 4A and 4B As shown, the molding apparatus 400 may include a top mold 410 and a bottom mold 420 that mates with the top mold 410. The top mold 410 and the bottom mold 420 define a molding cavity 430 for receiving a package substrate 440. The molding cavity 430 includes a flow inlet (not shown) for receiving molding fluid and a flow outlet (not shown) for discharging molding fluid after it has flowed through the molding cavity 430. As the molding fluid flows through the molding cavity 430, it may flow across the package substrate 440, or more specifically, the surface of the package substrate, in a generally flow direction from the flow inlet to the flow outlet. Thus, a portion of the molding fluid may be attached to the package substrate. In an embodiment, a plurality of electronic components 442 (such as semiconductor chips) may be mounted on the package substrate 440 via a collection of respective solder bumps 444 or other similar connection structures. The molding fluid can form a mold cap on the packaging substrate 440, which seals the electronic component 442 and the solder bumps 444 and prevents external contaminants and damage.
[0029] In one embodiment, the bottom mold 420 is formed as a generally flat plate or platform, while the top mold 410 is formed as a cover having sidewalls 446 extending from the body. Therefore, the molding cavity 430 formed by the bottom mold 420 and the top mold 410 can have a shape generally defined by the interior of the top mold 410. Furthermore, the encapsulation substrate 440 can be placed on the bottom surface of the bottom mold 420 and thus accommodated within the molding cavity 430. Although in Figure 4B and 4C The sidewall 446 is shown inclined relative to the bottom mold sleeve 420, but in some alternative embodiments, the sidewall 446 may be substantially perpendicular to the bottom mold sleeve 420. During molding processes such as injection molding, the sidewall 446 may come into contact with molding fluid flowing within the molding cavity 430.
[0030] The molding cavity 430 may further include a flow control structure located at or near two sidewalls 446 of the molding cavity 430 relative to the flow direction of the molding fluid to reduce the flow velocity of the molding fluid near the two sidewalls 446. The flow control structure can take various forms to control the flow velocity of the molding fluid. In an embodiment, the flow control structure may be configured to have an angled shape relative to the flow direction, that is, the distance between the two sidewalls 446 of the molding cavity 430 decreases in the flow direction A. Figure 4BAs shown, the distance G1 from the sidewall 446 to the electronic component 442 on the packaging substrate 440 at a cross-section of the molding apparatus 400 closer to the flow inlet of the molding cavity 430 is significantly greater than the distance G2 at a cross-section of the molding apparatus 400 closer to the flow outlet of the molding cavity 430. Figure 4C (as shown in the image).
[0031] As the distance between the two sidewalls 446 decreases, the flow rate of the molding fluid near the sidewalls 446 may slow down due to the higher fluid pressure. This deceleration compensates for the velocity difference between the fluid flow near the sidewalls 446 and the fluid flow at the center of the molding cavity 430, where the encapsulation substrate 440 may have various electronic components 442 mounted thereon that can reduce the flow rate of the molding fluid. In this way, lateral non-uniform distribution of the fluid flow closer to the flow outlet of the molding cavity 440 can be avoided, and thus mold defects such as voids can be reduced or avoided.
[0032] In some embodiments, the distance G1 between each sidewall 446 of the molding cavity 430 and the corresponding edge of the encapsulation strip placed in the molding apparatus 400 is at least 1.535 mm. It should be noted that the edge of the encapsulation substrate 440 is the edge of the electronic component array, not the edge of the encapsulation substrate 440 itself. Furthermore, the distance G2 between each sidewall 446 and the corresponding edge of the encapsulation strip at the flow outlet is narrower than the distance G1. The width of distance G2 is less than 1.535 mm, for example, it may be 0.400 mm, 0.200 mm, or even narrower. The distance G1 at the flow inlet can be configured to be substantially the same as the distance of a conventional mold sleeve.
[0033] In some alternative embodiments, the flow control structure may employ other designs. As an example, in some embodiments, the flow control structure may use one or more additional obstructions to impede the flow of mold flow without altering the shape of the molding cavity.
[0034] Figure 5A and 5B A molding apparatus 500 according to another embodiment of this application is shown. Specifically... Figure 5A A top view of the molding equipment 500 is shown, and Figure 5B A cross-sectional view of a portion of the molding equipment 500 is shown.
[0035] like Figure 5A and 5BAs shown, the flow control structure of the molding apparatus 500 may include at least one stop 548 protruding toward the molding cavity 530 defined by the top mold sleeve 510 and the bottom mold sleeve 520. Since the at least one stop 548 occupies a portion of the edge region above the encapsulation substrate housed within the molding cavity 540, it impedes the flow of molding fluid near the sidewall 546. Similar to... Figures 4A to 4C In the embodiment shown, the reduced flow rate compensates for the velocity difference between the fluid flow near the sidewall 546 and the fluid flow at the center of the molding cavity 530. In this way, lateral non-uniform distribution of the fluid flow closer to the flow outlet of the molding cavity 540 can be avoided, and thus mold defects such as voids can be reduced or avoided.
[0036] Specifically, such as Figure 5B As shown, at least one stop 548 may be formed on the body of the top mold 510 and extend downward toward the bottom mold 520. However, the stop 548 is typically closer to the sidewall 546 because it needs to occupy the gap between the sidewall 546 and the encapsulation strip. In some alternative embodiments, the stop 548 may be formed on the sidewall 546 and extend horizontally along the surface of the encapsulation substrate 540. Furthermore, to facilitate subsequent removal of the encapsulation strip from the top mold 510, the stop 548 may have a conical shape. Preferably, at least one stop 548 and the top mold 510 may be integrally formed as a single piece. Figure 5B In the embodiment shown, five stops 548 are formed on each sidewall of the molding cavity 530; however, another number of stops 548 may be formed, such as three, four, six or more. Furthermore, the cross-sectional area or length of the stops 548 in the molding cavity 530 may be varied, for example, by increasing the number of stops 548 closer to the flow outlet.
[0037] Similarly, although not shown in these figures, at least one blocking element may be formed on the bottom mold sleeve near each of the two sidewalls. In other words, near each of the two sidewalls, the flow control structure may include at least one blocking element extending from the body portion of the bottom mold sleeve toward the molding cavity.
[0038] Figure 6A and 6B Showing the target based on Figures 4A to 4C as well as Figures 5A to 5B The simulation results of two mold flows for high-density encapsulation strips in the molding cavity of the two embodiments shown are illustrated. Figure 6A and 6B As shown in the paper, mold defects such as voids can be effectively improved.
[0039] In the exemplary embodiments described above, different embodiments are shown of flow control structures implemented by angulating the sidewalls of the molding cavity and flow control structures implemented by at least one flow barrier, which can be combined into a single embodiment. For example, the flow control structure may be configured such that the gap between the sidewall of the molding cavity and the corresponding edge of the encapsulation strip decreases in the flow direction, and it may be further configured to arrange one or more flow barriers at or near the sidewall of the molding cavity.
[0040] Furthermore, the embodiments of the flow control structures shown in the above examples are merely exemplary, and this application is not limited thereto. In other embodiments, any flow control structure capable of reducing the cross-section of the molding cavity along the flow direction or capable of reducing the flow velocity of the molding fluid near the sidewalls of the molding cavity may also be applied in this application.
[0041] Figure 7 A flowchart illustrating a method 700 for manufacturing an electronic package according to an embodiment of this application is shown.
[0042] refer to Figure 7 Method 700 may begin at block 710, in which a packaging strip is placed in a molding cavity having a flow inlet, a flow outlet, sidewalls relative to the flow direction from the flow inlet to the flow outlet, and flow control structures located at or near the sidewalls. Next, at block 720, molding fluid is received at the flow inlet, and at block 730, the molding fluid is directed from the flow inlet toward the flow outlet of the molding cavity such that, as the molding fluid flows through the packaging strip, the flow control structures reduce the flow rate of the molding fluid near the sidewalls. At block 740, the molding fluid is output at the flow outlet. The functions and structures of the above components, including the molding cavity, the flow inlet, the flow outlet, and the sidewalls, have been described in detail above; for the sake of brevity, redundant descriptions are omitted herein.
[0043] The discussion herein includes numerous illustrative figures illustrating various parts of an electronic package and methods for manufacturing the electronic package. For clarity, such figures do not show all aspects of each example assembly. Any example device and / or method provided herein may share any or all characteristics with any and / or all other devices and / or methods provided herein. It should be understood that embodiments described in the context of one of a plurality of devices or methods are similarly effective for other devices or methods. Similarly, embodiments described in the context of a device are similarly effective for a method, and vice versa. Features described in the context of one embodiment may be correspondingly applied to the same or similar features in other embodiments. Features described in the context of one embodiment may be correspondingly applied to other embodiments, even if not explicitly described in those other embodiments. Furthermore, additions and / or combinations and / or alternatives described for features in the context of one embodiment may be correspondingly applied to the same or similar features in other embodiments.
[0044] Various embodiments have been described herein with reference to the accompanying drawings. However, it will be apparent that various modifications and alterations can be made thereto, and other embodiments may be practiced, without departing from the broader scope of the invention as set forth in the appended claims. Furthermore, other embodiments will be apparent to those skilled in the art upon consideration of the practice of one or more embodiments of the invention disclosed herein. Therefore, the examples in this application and herein are intended to be considered exemplary only, and the true scope and spirit of the invention are indicated by the following list of exemplary claims.
Claims
1. A molding apparatus characterized by comprising: Comprising: a top mold half; a bottom mold half mateable with the top mold half, wherein the top mold half and the bottom mold half together define a molding cavity for receiving a packaging strip, and the molding cavity includes a flow input configured to receive a molding fluid and a flow output configured to output the molding fluid after the molding fluid flows through the molding cavity and over the packaging strip in a flow direction generally from the flow input to the flow output, wherein the molding cavity further includes a flow control structure at or proximate to two side walls of the molding cavity relative to the flow direction to reduce a flow rate of the molding fluid proximate to the two side walls.
2. The molding apparatus of claim 1, wherein, The flow control structure is configured such that a distance between the two side walls of the molding cavity decreases along the flow direction.
3. The molding apparatus of claim 1, wherein, The packaging strip is disposed at a central location of the molding cavity in a lateral direction of the molding cavity generally perpendicular to the flow direction, and the flow control structure is configured such that a gap between a side wall of the molding cavity and a corresponding edge of the packaging strip decreases along the flow direction.
4. The molding apparatus of claim 3, wherein, A width of the gap at the flow output is less than 1.535 mm.
5. The molding apparatus of claim 1, wherein, On each of the two side walls, the flow control structure includes at least one barrier protruding from the side wall toward the molding cavity.
6. The molding apparatus of claim 5, wherein, The plurality of side walls are part of the top mold half, and the at least one barrier and the top mold half are integrally formed as a single piece.
7. The molding apparatus of claim 1, wherein, At proximate to each of the two side walls, the flow control structure includes at least one barrier extending from a main portion of the top mold half or a main portion of the bottom mold half toward the molding cavity.
8. The molding apparatus of claim 1, wherein, The flow control structure is configured such that a cross-section of the molding cavity decreases along the flow direction.
9. The molding apparatus of claim 1, wherein, The flow control structure is configured to reduce the flow rate of the molding fluid proximate to the two side walls such that a void of the molding fluid at or proximate to the flow output is avoided.
10. A method for manufacturing an electronic package, characterized by, The method comprises: placing a packaging strip in a molding cavity having a flow input, a flow output, a plurality of side walls relative to a flow direction from the flow input to the flow output, and a flow control structure at or proximate to the plurality of side walls; receiving a molding fluid at the flow input; directing the molding fluid from the flow input toward the flow output of the molding cavity such that the flow control structure reduces a flow rate of the molding fluid proximate to the plurality of side walls as the molding fluid flows over the packaging strip; and outputting the molding fluid at the flow output.
11. The method of claim 10, wherein, The flow control structure is configured such that a distance between the plurality of side walls of the molding cavity decreases along the flow direction.
12. The method of claim 10, wherein, The packaging strip is disposed at a central location of the molding cavity in a lateral direction of the molding cavity generally perpendicular to the flow direction, and the flow control structure is configured such that a gap between a side wall of the molding cavity and a corresponding edge of the packaging strip decreases along the flow direction.
13. The method of claim 12, wherein, The width of the gap at the flow output is less than 1.535 mm.
14. The method of claim 10, wherein, On each of the plurality of side walls, the flow control structure includes at least one barrier protruding from the side wall toward the molding cavity.
15. The method of claim 14, wherein, The plurality of side walls are part of the top mold jacket, and the at least one barrier and the top mold jacket are integrally formed as a single piece.
16. The method of claim 10, wherein, At each of the plurality of side walls, the flow control structure includes at least one barrier extending from a body portion of the top mold jacket or a body portion of the bottom mold jacket toward the molding cavity.
17. The method of claim 10, wherein, The flow control structure is configured such that a cross-section of the molding cavity decreases along the flow direction.
18. The method of claim 10, wherein, The flow control structure is configured to reduce the flow rate of the molding fluid near the plurality of side walls such that voids of the molding fluid at or near the flow output are avoided.