Methods and fixtures for improving warpage in substrate packaged products

Abstract

This invention discloses a method and fixture for improving the warpage of a substrate package product, comprising the steps of: providing at least one substrate package product; providing a fixture for improving the warpage of the substrate package product, which includes a support member and a pressure member disposed on the upper surface of the support member, wherein the lower surface of the pressure member and the upper surface of the support member protrude in the same direction in their width direction, and when the pressure member is placed on the support member, the upper surface of the support member and the lower surface of the pressure member are in contact with each other; placing the back side of the lead frame facing the opposite direction of the protrusion direction between the support member and the pressure member; and performing a curing process on the substrate package product loaded in the fixture. Due to the function of the fixture, the direction of stress release due to the difference in the coefficient of thermal expansion of the materials is guided after curing, and part of the stress is released from the length direction of the substrate package product to the width direction of the substrate package product, thereby significantly reducing the overall warpage of the cured product.

Description

Technical Field

[0001] This invention relates to the field of semiconductor packaging technology, and in particular to a method and fixture for improving the warpage of substrate packaged products. Background Technology

[0002] Existing substrate packaging products mainly consist of lead frames, inks, and molding compounds. Due to the significant differences in the coefficients of thermal expansion of the lead frames, inks, and molding compounds, stress is generated during the curing of the ink at high temperatures. This stress can cause warping during the cooling process, affecting subsequent processes, especially for thin substrate packaging (product thickness less than 0.5 mm).

[0003] For example, regarding the impact on electroplating and cutting processes: 1. Electroplating jamming: When the product warps beyond 5mm of the allowable range of the electroplating tank inlet / outlet and the material drop sensor, it will cause the product to impact the tank inlet / outlet or the material drop sensor base, which may cause the plastic seal to break; 2. Cutting deviation: If the product warps beyond 5mm, the vacuum suction of the cutting equipment will not be able to completely flatten the product, and the product will not be in a horizontal state on the cutting platform. The cutting path will be offset, resulting in cutting deviation, which will lead to product dimensional defects and residual ribs and burrs. Summary of the Invention

[0004] The purpose of this invention is to provide a method and fixture for improving the warpage of substrate packaged products.

[0005] To achieve one of the above-mentioned objectives, one embodiment of the present invention provides a method for improving the warpage of a substrate package product. The substrate package product includes a lead frame, the lead frame having a front side with a molding compound formed on one side and a back side opposite to the front side. The substrate package product defines a width and a length, wherein the length of the substrate package product is greater than the width of the substrate package product. The method includes the following steps:

[0006] Provide at least one of the substrate-packaged products described above;

[0007] A fixture for improving warpage of a substrate packaged product is provided. The fixture defines a fixture length and a fixture width, wherein the fixture length is greater than the fixture width. The fixture includes a support member and a pressure member disposed on the upper surface of the support member. The lower surface of the pressure member and the upper surface of the support member protrude in the same direction in their width direction. When the pressure member is placed on the support member, the upper surface of the support member and the lower surface of the pressure member are in contact with each other.

[0008] With the back of the lead frame facing the opposite direction of the protrusion, and the width direction of the substrate package product corresponding to the width direction of the fixture, it is placed between the support member and the pressure member.

[0009] The substrate packaged product, which is mounted in the fixture, undergoes a curing process.

[0010] As a further improvement in one embodiment of the present invention, the fixture for improving the warpage of a substrate packaged product specifically includes:

[0011] Provide pressure components weighing at least 4 kg.

[0012] As a further improvement in one embodiment of the present invention, the fixture for improving warpage of a substrate packaged product further includes:

[0013] A fixture is provided that has a length and width smaller than the length and width of the substrate packaged product, and larger than the length and width of the area enclosed by the molding compound.

[0014] As a further improvement in one embodiment of the present invention, the lower surface of the pressure component and the upper surface of the bearing component protrude in the same direction in their width direction. When the pressure component is placed on the bearing component, the upper surface of the bearing component and the lower surface of the pressure component are in contact with each other, specifically including:

[0015] The lower surface of the pressure component and the upper surface of the bearing component both protrude in the same direction along their width to form a smooth arc surface. When the pressure component is placed on the bearing component, the smooth arc surface of the bearing component and the smooth arc surface of the pressure component fit together.

[0016] As a further improvement in one embodiment of the present invention, the lower surface of the pressure component and the upper surface of the bearing component both protrude in the same direction along their width to form a smooth arc surface, specifically including:

[0017] The lower surface of the pressure component forms a smooth arc surface that protrudes in the width direction toward the bearing component;

[0018] The upper surface of the supporting component forms a smooth, concave arc surface in the width direction toward the supporting component.

[0019] As a further improvement in one embodiment of the present invention, the method specifically includes:

[0020] The protrusion height of the smooth arc surface on the lower surface of the pressure component is set to 1.5mm, and the concavity height of the smooth arc surface on the upper surface of the bearing component is set to 1.5mm.

[0021] As a further improvement in one embodiment of the present invention, the step of placing the back side of the lead frame facing the opposite direction to the protrusion direction, and placing the substrate package product in the width direction corresponding to the width direction of the fixture between the bearing member and the pressure member, specifically includes:

[0022] A spacer material is also placed between the substrate packaged product and the support component and the pressure component, respectively.

[0023] As a further improvement in one embodiment of the present invention, the method specifically includes:

[0024] A plurality of substrate packaged products are provided, and the plurality of substrate packaged products are stacked in the same direction, with a layer of spacer material placed between each substrate packaged product and another substrate packaged product.

[0025] With the back of the lead frame facing the opposite direction of the protrusion, and the width direction of the stacked substrate package products corresponding to the width direction of the fixture, the product is positioned between the support member and the pressure member.

[0026] One embodiment of the present invention also provides a fixture for improving the warpage of a substrate package product. The fixture is used to load the substrate package product, which includes a lead frame having a front side with a molding compound formed on one side and a back side opposite to the front side. The substrate package product defines a width and a length, wherein the length is greater than the width.

[0027] The fixture defines a fixture length and a fixture width, wherein the fixture length is greater than the fixture width, and includes a support component and a pressure component disposed on the upper surface of the support component. The lower surface of the pressure component and the upper surface of the support component protrude in the same direction in their width direction. When the pressure component is placed on the support component, the upper surface of the support component and the lower surface of the pressure component are in contact with each other.

[0028] As a further improvement in one embodiment of the present invention, the pressure component is configured to weigh more than 4 kg.

[0029] As a further improvement in one embodiment of the present invention, the length and width of the fixture are smaller than the length and width of the substrate, but larger than the length and width of the area enclosed by the molding compound.

[0030] As a further improvement in one embodiment of the present invention, the lower surface of the pressure component and the upper surface of the bearing component both protrude in the same direction in their width direction to form a smooth arc surface. When the pressure component is placed on the bearing component, the smooth arc surface of the bearing component and the smooth arc surface of the pressure component fit together.

[0031] As a further improvement in one embodiment of the present invention, the lower surface of the pressure component forms a raised smooth arc surface in the width direction toward the bearing component, and the upper surface of the bearing component forms a recessed smooth arc surface in the width direction toward the bearing component.

[0032] As a further improvement in one embodiment of the present invention, the protrusion height of the smooth arc surface protruding on the lower surface of the pressure component is set to 1.5 mm, and the concave height of the smooth arc surface recessed on the upper surface of the bearing component is set to 1.5 mm.

[0033] As a further improvement in one embodiment of the present invention, the fixture further includes a handle component disposed on the upper surface of the pressure component.

[0034] The beneficial effects of this invention are as follows: by loading the substrate packaged product into the fixture provided in this invention to improve substrate package warpage and performing a curing process, the fixture guides the change in the stress release direction of the cured substrate packaged product due to the difference in thermal expansion coefficients between materials, releasing some of the stress from the length direction of the substrate packaged product to the width direction of the substrate packaged product, greatly reducing the overall warpage of the cured product, reducing the risk of electroplating jamming and cutting deviation in subsequent processes, and improving the product manufacturing yield. Attached Figure Description

[0035] Figure 1 This is a schematic flowchart of a method for improving warpage of a substrate packaging product according to an embodiment of the present invention.

[0036] Figures 2a to 2d2 This is a process step diagram of a method for improving warpage of a substrate packaged product according to an embodiment of the present invention.

[0037] Figure 3a This is a structural effect diagram of a substrate packaged product after curing without the use of a fixture, according to one embodiment of the present invention.

[0038] Figure 3b This is a structural effect diagram of a substrate-encapsulated product after curing using a fixture, according to one embodiment of the present invention.

[0039] Figure 4a This is a schematic diagram of a fixture structure for improving warpage in a substrate packaging product according to one embodiment of the present invention. (The pressure component and the load-bearing component are separate.)

[0040] Figure 4b This is a schematic diagram of a fixture structure for improving warpage in a substrate packaging product according to one embodiment of the present invention. (Pressure component and load-bearing component are closed.)

[0041] Figure 5 This is a side view of a fixture structure for improving warpage in a substrate packaging product according to an embodiment of the present invention. (The pressure component and the load-bearing component are separate.) Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0043] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0044] For ease of explanation, this document uses terms indicating relative spatial position, such as "above," "below," "behind," and "front," to describe the relationship of one unit or feature shown in the accompanying drawings relative to another unit or feature. Terms indicating relative spatial position can include different orientations of the device during use or operation besides those shown in the figures. For example, if the device in the figures is flipped, a unit described as being "below" or "above" other units or features will be located "below" or "above" other units or features. Therefore, the exemplary term "below" can encompass both "below" and "above" spatial orientations.

[0045] One embodiment of the present invention provides a method for improving the warpage of substrate packaged products, such as... Figure 1 As shown, the steps include:

[0046] S1: Provide at least one substrate packaged product.

[0047] S2: Provides a fixture for improving the warpage of a substrate packaged product. The fixture defines a fixture length and a fixture width. The fixture length is greater than the fixture width. It includes a support member and a pressure member disposed on the upper surface of the support member. The lower surface of the pressure member and the upper surface of the support member protrude in the same direction in their width direction. When the pressure member is placed on the support member, the upper surface of the support member and the lower surface of the pressure member are in contact with each other.

[0048] S3: With the back of the lead frame facing the opposite direction of the protrusion, and the width direction of the substrate package product corresponding to the width direction of the fixture, it is placed between the support component and the pressure component.

[0049] S4: Perform a curing process on the substrate packaged product mounted in the fixture.

[0050] In step S1, at least one substrate packaged product is provided, specifically including:

[0051] like Figure 2a As shown, a substrate package product 1 according to an embodiment of the present invention includes a lead frame 11. The lead frame 11 has a front side on the side where the molding compound 12 is formed and a back side opposite to the front side. The substrate package product 1 defines a substrate package product width and a substrate package product length, and the substrate package product length is set to be greater than the substrate package product width.

[0052] Specifically, one side of the lead frame 11 is covered with molding compound 12, and ink is formed on the back side of the lead frame 11 at the position corresponding to the molding compound 12. When the thickness of the substrate package product 1 is less than 0.5 mm, the thermal expansion coefficients of the lead frame 11, molding compound 12 and ink materials differ significantly during the curing process, resulting in significant warping of the cured substrate package product 1, which necessitates the use of the fixture in step S2.

[0053] In step S2, a fixture 2 for improving the warpage of the substrate packaged product is provided, specifically including:

[0054] like Figure 2b As shown, a fixture 2 for improving the warpage of a substrate packaging product is provided in one embodiment of the present invention. Specifically, the fixture 2 has an overall cuboid structure, and the length and width of the fixture 2 are defined, with the length of the fixture 2 being greater than the width of the fixture 2.

[0055] The fixture 2 includes a support member 21 and a pressure member 22 disposed on the upper surface of the support member 21. Similarly, the surfaces of the support member 21 and the pressure member 22 are rectangular, having a length direction and a width direction. In the length direction, the side lengths of the support member 21 and the pressure member 22 are the same, and in the width direction, the side lengths of the support member 21 and the pressure member 22 are the same. However, the side lengths of the support member 21 and the pressure member 22 in the length direction are greater than the side lengths of the support member 21 and the pressure member 22 in the width direction.

[0056] This invention does not specify the exact thickness and weight of the provided support component 21, but the weight of the provided pressure component 22 must be greater than 4 kg to completely fix the substrate-encapsulated product 1 and reduce its warpage. To facilitate operation by technicians, in the preferred embodiment of this invention, the weight of the provided pressure component 22 is controlled between 4 kg and 6 kg.

[0057] Of course, the provided fixture 2 must meet the requirement that its length and width are less than the length and width of the substrate package product 1, and greater than the length and width of the area enclosed by the molding compound 12. That is, the length and width of the provided support component 21 and pressure component 22 must be less than the length and width of the substrate package product 1, and greater than the length and width of the area enclosed by the molding compound 12 in the substrate package product 1, so as to facilitate loading or removing the substrate package product 1 from the fixture 2 in subsequent process manufacturing, and to ensure that the boundary between the upper surface of the support component 21 and the lower surface of the pressure component 22 will not press against the area of ​​the molding compound 12 in the lead frame 11.

[0058] In a specific embodiment of the present invention, the provided substrate package product 1 has a size of 250mm*70mm. To ensure convenient placement of the substrate package product 1 into the fixture 1 during subsequent operations, the specific dimensions of the provided support component 21 and pressure component 22 are 249mm*68mm. Of course, the specific dimensions of the support component 21 and pressure component 22 are not limited to this and can be designed according to the specific dimensions of the substrate package product 1. It is only necessary to ensure that the length and width of the provided support component 21 and pressure component 22 are smaller than the length and width of the substrate package product 1, respectively, and larger than the length and width of the area encapsulated by the molding compound 12 within the substrate package product 1.

[0059] Specifically, the lower surface of the pressure component 22 and the upper surface of the bearing component 21 both protrude in the same direction in their width direction to form a smooth arc surface. When the pressure component 22 is placed on the bearing component 21, the smooth arc surface of the bearing component 21 and the smooth arc surface of the pressure component 22 fit together.

[0060] For more details, please see [link / reference]. Figure 2b The lower surface of the pressure component 22 forms a raised smooth arc surface 221 in the width direction toward the bearing component 21, and the upper surface of the bearing component 21 forms a recessed smooth arc surface 211 in the width direction toward the bearing component 21. The raised smooth arc surface 221 and the recessed smooth arc surface 211 cooperate with each other, that is, when the bearing component 21 and the pressure component 22 are combined, the upper surface of the bearing component 21 and the lower surface of the pressure component 22 are completely fitted together without gaps.

[0061] In a specific embodiment of the present invention, the provided substrate package product 1 has a length of 250 mm, a width of 70 mm, and a thickness of less than 0.5 mm. The protrusion height of the smooth arc surface 221 protruding from the lower surface of the pressure member 22 is [not specified]. d1 Set to 1.5mm, which is the recess height of the smooth arc surface 211 on the upper surface of the bearing component 21. d2 Setting it to 1.5mm allows for changing the stress release direction of the substrate package 1 when it is placed in the fixture 2 for curing. This releases the stress in the length direction of the substrate package 1 to the width direction, reducing or even eliminating warpage in the length direction and thus mitigating overall warpage. Of course, for most existing substrate package products on the market, the protrusion height of the smooth arc surface 221 on the lower surface of the pressure component 22 is... d1 Set to 1.5mm, which is the recess height of the smooth arc surface 211 on the upper surface of the bearing component 21. d2 Setting it to 1.5mm can also meet the technical requirement of reducing the overall warpage of the substrate package product 1 when it is placed in the fixture 2 for curing.

[0062] Of course, in other embodiments of the present invention, the specific dimensions of the substrate packaged product 1 are not limited to this, and the corresponding height of the smooth arc surface 221 of the lower surface of the pressure member 2 in the fixture 2 is also considered. d1 The recess height of the smooth arc surface 211 on the upper surface of the supporting component 21 d2 The specific adjustments can be made based on the specific manufacturing materials and dimensions of the substrate packaged product 1, as long as the above-mentioned technical effects can be met.

[0063] Furthermore, the fixture 2 provided in step S2 also includes a handle component 23 formed on the upper surface of the pressure component 22, facilitating the handling of the pressure component 22 by technicians. The specific size and shape of the handle component 23 are not limited herein and can be designed according to actual needs. Specifically, the handle component 23 and the pressure component 22 are integrated; however, in other embodiments, the handle component 23 and the pressure component 22 can also be designed as separate, detachable units.

[0064] Preferably, the jig 2 is made of carbon steel. Of course, it can also be made of other materials that have hardness and high temperature resistance. This invention does not limit this.

[0065] In step S3, the back side of the lead frame 11 is oriented in the opposite direction to the protrusion direction, and the width direction of the substrate package product 1 is aligned with the width direction of the fixture 2, and it is placed between the support member 21 and the pressure member 22. Specifically, this includes:

[0066] A spacer material 3 is placed between the substrate package product 1 and the support component 21 and the pressure component 22 respectively to protect the substrate package product 1. The spacer material 3 is specifically a layer of filter paper.

[0067] Specifically, such as Figure 2c1 As shown, before placing the substrate package product 1 on top of the support member 21, a layer of filter paper is first laid on the smooth, concave arc surface 211 of the support member 21. Then, the substrate package product 1 is placed on the filter paper. Specifically, the back side of the lead frame 11 faces the pressure member 22, and the width direction of the substrate package product 1 corresponds to the width direction of the support member 21, placing it directly above the support member 21. It should be noted that since one side of the front of the lead frame 11 is molding compound and the other side is ink, and because the ink material has a large coefficient of thermal expansion, attention must be paid to the orientation of the substrate package product 1 when placing it. The side with ink should face the opposite direction to the convex direction of the lower surface of the pressure member 22 and the upper surface of the support member 21. Therefore, in this embodiment, the side with ink, i.e., the back side of the lead frame 11, faces the pressure member 22.

[0068] Furthermore, another layer of filter paper is laid on top of the substrate packaged product 1.

[0069] like Figure 2d1 As shown, the pressure component 22 is positioned above the substrate package product 1, corresponding to the position of the support component 21.

[0070] In another embodiment of the present invention, unlike the above description, in this embodiment, the lower surface of the pressure member 22 provided in step S2 forms a concave smooth arc surface in the direction of the pressure member 22 in its width direction, and correspondingly, the upper surface of the support member 21 forms a convex smooth arc surface in the direction of the pressure member 22 in its width direction. In step S3, the substrate package product 1 is loaded into the fixture 2 with the back side of the lead frame 11 facing the support member 21.

[0071] Of course, in actual manufacturing, step S1 can provide multiple substrate packaged products 1, which are stacked in the same direction. A spacer material 3 is placed between each substrate packaged product 1 and another substrate packaged product 1. That is, in step S3, the back of the lead frame 11 faces the opposite direction of the protrusion, and the width direction of the stacked substrate packaged products 1 corresponds to the width direction of the fixture 2, and they are placed between the bearing member 21 and the pressure member 22. Figure 2c2 and Figure 2d2 As shown, batch processing of product curing technology improves operational efficiency.

[0072] In step S4, the substrate packaged product 1 mounted in the fixture 2 undergoes a curing process, specifically including:

[0073] The substrate packaged product 1, mounted in fixture 2, is placed in an oven for baking at 170°C for 4 hours. After baking, it is removed from the oven and allowed to cool to room temperature. The pressure component 22 is then removed. The cured substrate packaged product 1 exhibits only minor warping in its width direction and no warping in its length direction. The cured substrate packaged product 1 is free from twisting deformation, reducing the risk of plating jamming and cutting deviations in subsequent processes and improving product yield.

[0074] Here, the baking temperature and baking time can be adjusted according to the actual product manufacturing needs, and this invention does not impose any restrictions on them.

[0075] This invention takes a substrate packaging product with dimensions of 250mm*70mm as an example to briefly explain the principle of reducing overall product warpage and the final warpage value after curing using fixture 2. Due to the large differences in the coefficients of thermal expansion among materials such as molding compound, lead frame, and ink in the substrate packaging product, the stress generated between these materials after high-temperature baking and cooling can cause product deformation, i.e., warpage.

[0076] like Figure 3a and 3b As shown, Figure 3a The corresponding substrate-packaged product exhibits warping after curing without using the fixture 2 in this invention, resulting in significant warping along the product's length. Figure 3b The corresponding substrate packaged product exhibits warping after curing using the fixture 2 in this invention. Warping only occurs in the width direction of the product, with no warping in the length direction.

[0077] Assuming the deformation (called elastic modulus Δ) of the same product is constant, and the product is infinitely divided into segments, with the elastic modulus of each segment being Δ1, Δ2, Δ3, ..., Δn, then... Figure 3a The elastic modulus of the product is Δ = Δ' × 70 × 2, where Δ' is the elastic modulus along the length of the product. Figure 3b The elastic modulus of the product is Δ = Δ'' × 250 × 2, where Δ'' is the elastic modulus in the width direction of the product. Therefore, Δ'' is only 70 / 250 of Δ'. Calculations show that after curing with jig 2, the overall warpage of the product of this size can be reduced by more than 2 / 3.

[0078] In a specific embodiment of the present invention, the substrate packaged product 1 using the fixture 2 undergoes a curing process. Through the structural design of the fixture 2, the stress release direction of the substrate packaged product 1, loaded within the fixture 2, is guided in advance. This releases some of the stress in the length direction of the substrate packaged product 1 to its width direction, reducing the stress caused by the shrinkage of the long side (250mm) of the product during high-temperature baking and cooling, thereby reducing overall product warpage. Product warpage is mainly caused by shrinkage during cooling after ink curing. After curing and cooling to room temperature, when the pressure component 22 is removed, the residual stress caused by the mismatch in thermal expansion coefficients of the components of the substrate packaged product 1, chemical shrinkage, and uneven curing leads to further product warpage. Ultimately, the warpage of the substrate packaged product 1 cured using the fixture 2 in the width direction is approximately 4mm.

[0079] As shown in Figures 4 and 5, one embodiment of the present invention also provides a fixture 2 for improving the warpage of substrate packaged products. This fixture 2 is used to mount... Figure 2a The substrate package product 1 includes a lead frame 11, which has a front side on the side where the molding compound 12 is formed and a back side opposite to the front side. The substrate package product 1 defines a substrate package product width and a substrate package product length, wherein the substrate package product length is set to be greater than the substrate package product width.

[0080] Specifically, the front side of the lead frame 11 is covered with molding compound 12, and ink is formed on the back side of the lead frame 11 corresponding to the position of the molding compound 12. When the thickness of the substrate package product 1 is less than 0.5 mm, the thermal expansion coefficients of the lead frame 11, molding compound 12, and ink materials differ significantly during the curing process, resulting in significant warping of the cured substrate package product 1. Therefore, the fixture 2 in one embodiment of the present invention is required.

[0081] Specifically, the overall surface structure of fixture 2 is a cuboid structure. Similarly, the length and width of fixture 2 are defined, with the length of fixture 2 being greater than the width of fixture 2.

[0082] The fixture 2 includes a support member 21 and a pressure member 22 disposed on the upper surface of the support member 21. Similarly, the surfaces of the support member 21 and the pressure member 22 are rectangular, having a length direction and a width direction. In the length direction, the side lengths of the support member 21 and the pressure member 22 are the same, and in the width direction, the side lengths of the support member 21 and the pressure member 22 are the same. However, the side lengths of the support member 21 and the pressure member 22 in the length direction are greater than the side lengths of the support member 21 and the pressure member 22 in the width direction.

[0083] This invention does not specify the exact thickness and weight of the supporting component 21, but the weight of the pressure component 22 must be greater than 4 kg to completely fix the substrate-encapsulated product 1 and reduce its warpage. For ease of operation by technicians, in the preferred embodiment of this invention, the weight of the pressure component 22 is set between 4 kg and 6 kg.

[0084] Specifically, the length and width of the fixture 1 are smaller than the length and width of the substrate package product 1, and larger than the length and width of the area enclosed by the molding compound 12. That is, the length and width of the supporting component 21 and the pressure component 22 are smaller than the length and width of the substrate package product 1, and larger than the length and width of the area enclosed by the molding compound 12 in the substrate package product 1. This is to facilitate loading or removing the substrate package product 1 from the fixture 2 in subsequent manufacturing processes, and to ensure that the boundary between the upper surface of the supporting component 21 and the lower surface of the pressure component 22 does not press against the area of ​​the molding compound 12 in the lead frame 11.

[0085] In a specific embodiment of the present invention, the substrate packaged product 1 has a size of 250mm*70mm. To ensure convenient placement of the substrate packaged product 1 into the fixture 1 during subsequent operations, the specific dimensions of the supporting component 21 and the pressure component 22 are set to 249mm*68mm. Of course, the specific dimensions of the supporting component 21 and the pressure component 22 are not limited to this and can be designed according to the specific dimensions of the substrate packaged product 1. It is only necessary to ensure that the length and width of the supporting component 21 and the pressure component 22 are smaller than the length and width of the substrate packaged product 1, respectively, and larger than the length and width of the area encapsulated by the molding compound 12 within the substrate packaged product 1.

[0086] Furthermore, the lower surface of the pressure component 22 and the upper surface of the support component 21 protrude in the same direction along their width. When the pressure component is placed on the support component, the upper surface of the support component and the lower surface of the pressure component are in contact with each other. Specifically, the lower surface of the pressure component 22 and the upper surface of the support component 21 both protrude in the same direction along their width to form a smooth arc surface. When the pressure component 22 is placed on the support component 21, the smooth arc surface of the support component 21 and the smooth arc surface of the pressure component 22 are in contact with each other.

[0087] In one embodiment of the present invention, the lower surface of the pressure member 22 forms a raised smooth arc surface 221 in its width direction toward the bearing member 21, and the upper surface of the bearing member 21 forms a recessed smooth arc surface 211 in its width direction toward the bearing member 21. The raised smooth arc surface 221 and the recessed smooth arc surface 211 cooperate with each other, that is, when the bearing member 21 and the pressure member 22 are combined, the upper surface of the bearing member 21 and the lower surface of the pressure member 22 are completely fitted together without gaps. Figure 4b As shown.

[0088] In a specific embodiment of the present invention, the substrate packaged product 1 has a length of 250 mm, a width of 70 mm, and a thickness of less than 0.5 mm. The protrusion height of the smooth arc surface 221 protruding from the lower surface of the pressure component 22 is... d1 The recess height of the smooth arc surface 211 on the upper surface of the bearing component 21 is set to 1.5mm. d2 Setting it to 1.5mm allows for changing the stress release direction of the substrate package 1 when it is placed in the fixture 2 for curing. This releases the stress in the length direction of the substrate package 1 to the width direction, reducing or even eliminating warpage in the length direction and thus mitigating overall warpage. Of course, for most existing substrate package products on the market, the protrusion height of the smooth arc surface 221 on the lower surface of the pressure component 22 is... d1 Set to 1.5mm, which is the recess height of the smooth arc surface 211 on the upper surface of the bearing component 21. d2 Setting it to 1.5mm can also meet the technical requirement of reducing the overall warpage of the substrate package product 1 when it is placed in the fixture 2 for curing.

[0089] The specific dimensions of the substrate packaged product 1 are not limited to this, but also include the protrusion height of the smooth arc surface 221 on the lower surface of the pressure component 22 in the corresponding fixture 2. d1 The recess height of the smooth arc surface 211 on the upper surface of the supporting component 21 d2 The specific adjustments can be made based on the specific manufacturing materials and dimensions of the substrate packaged product 1, as long as the above-mentioned technical effects can be met.

[0090] In another embodiment of the present invention, the lower surface of the pressure member 22 forms a concave smooth arc surface in the width direction toward the pressure member 22, and correspondingly, the upper surface of the support member 21 forms a convex smooth arc surface in the width direction toward the pressure member 22. In this embodiment, it is only necessary to ensure that the back side of the lead frame 11 faces the support member 21 when the substrate package product 1 is placed in the fixture 2 in the subsequent process. This corresponds to the precautions mentioned in the method steps above for placing the substrate package product 1, and the present invention will not elaborate further here.

[0091] Furthermore, the fixture 2 also includes a handle component 23 disposed on the upper surface of the pressure component 22, facilitating the handling of the pressure component 22 by technicians. The specific size and shape of the handle component 23 are not limited herein and can be designed according to actual needs. Specifically, the handle component 23 and the pressure component 22 are integrally formed; however, in other embodiments, the handle component 23 and the pressure component 22 can also be designed as separate, detachable units.

[0092] Preferably, the jig 2 is made of carbon steel. Of course, it can also be made of other materials that have hardness and high temperature resistance. This invention does not limit this.

[0093] In summary, this invention involves loading the substrate packaged product into a fixture provided in this invention to improve substrate package warpage during the curing process. Due to the function of the fixture, the stress release direction of the cured substrate packaged product due to the difference in thermal expansion coefficients between materials is changed, and some stress is released from the length direction of the substrate packaged product to the width direction of the substrate packaged product. This significantly reduces the overall warpage of the cured product, reduces the risk of electroplating jamming and cutting deviation in subsequent processes, and improves the product manufacturing yield.

[0094] It should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0095] The detailed descriptions listed above are merely specific descriptions of feasible embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for improving warpage of a substrate package product, the substrate package product including a lead frame having a front side with a molding compound formed thereon and a back side opposite to the front side, the substrate package product defining a substrate package product width and a substrate package product length, the substrate package product length being greater than the substrate package product width, characterized in that, The method includes the following steps: Provide at least one of the substrate packaging products, wherein the thickness of the substrate packaging product is less than 0.5 mm; A fixture for improving warpage in substrate packaged products is provided. The fixture defines a fixture length and a fixture width, wherein the fixture length is greater than the fixture width. It includes a support member and a pressure member disposed on the upper surface of the support member. The pressure member weighs 4 kg to 6 kg. The lower surface of the pressure member forms a raised, smooth arc surface in its width direction toward the support member; the upper surface of the support member forms a recessed, smooth arc surface in its width direction toward the support member. The protrusion height of the raised smooth arc surface on the lower surface of the pressure member is set to 1.5 mm, and the recess height of the recessed smooth arc surface on the upper surface of the support member is set to 1.5 mm. When the pressure member is placed on the support member, the upper surface of the support member and the lower surface of the pressure member are in contact with each other. With the back of the lead frame facing the opposite direction of the protrusion direction, and the width direction of the substrate package product corresponding to the width direction of the fixture, it is placed between the support member and the pressure member. The substrate packaged product, which is mounted in the fixture, undergoes a curing process.

2. The method for improving warpage of substrate packaged products according to claim 1, characterized in that, The fixture for improving warpage of substrate packaged products further includes: A fixture is provided that has a length and width smaller than the length and width of the substrate packaged product, and larger than the length and width of the area enclosed by the molding compound.

3. The method for improving warpage of substrate packaged products according to claim 1, characterized in that, The step of placing the back side of the lead frame facing the opposite direction of the protrusion direction, and positioning the substrate package product with its width direction corresponding to the width direction of the fixture, between the support member and the pressure member, specifically includes: A spacer material is also placed between the substrate packaged product and the support component and the pressure component, respectively.

4. The method for improving warpage of substrate packaged products according to claim 1, characterized in that, The method further includes: Provide multiple substrate packaged products, stack the multiple substrate packaged products in the same direction, and place a spacer material between each substrate packaged product and another substrate packaged product; With the back of the lead frame facing the opposite direction of the protrusion, and the width direction of the stacked substrate package products corresponding to the width direction of the fixture, the product is positioned between the support member and the pressure member.

5. A fixture for improving warpage of a substrate package product, the fixture being used to improve warpage of a substrate package product with a thickness of less than 0.5 mm, the substrate package product including a lead frame having a front side with a molding compound formed thereon and a back side opposite to the front side, the substrate package product defining a substrate package product width and a substrate package product length, the substrate package product length being greater than the substrate package product width, characterized in that... The fixture defines a fixture length and a fixture width, with the fixture length being greater than the fixture width. It includes a support component and a pressure component disposed on the upper surface of the support component. The pressure component weighs 4 kg to 6 kg. The lower surface of the pressure component forms a raised smooth arc surface in its width direction toward the support component, and the upper surface of the support component forms a recessed smooth arc surface in its width direction toward the support component. The protrusion height of the raised smooth arc surface on the lower surface of the pressure component is set to 1.5 mm, and the recess height of the recessed smooth arc surface on the upper surface of the support component is set to 1.5 mm. When the pressure component is placed on the support component, the upper surface of the support component and the lower surface of the pressure component are in contact with each other.

6. The fixture for improving warpage of substrate packaged products according to claim 5, characterized in that, The length and width of the fixture are less than the length and width of the substrate, but greater than the length and width of the area enclosed by the molding compound.

7. The fixture for improving warpage of substrate packaged products according to claim 5, characterized in that, The fixture also includes a handle component disposed on the upper surface of the pressure component.

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