TWI824672B - Packaging structure and its metal components - Google Patents

Abstract

The present invention provides a packaging structure and its metal component, wherein the metal component includes a plurality of grooves, each groove is linear and has a V-shaped cross-section, so that each groove has two opposite inner sides. At least one anchoring structure is protruding from at least one inner surface of each groove. The at least one anchoring structure forms a necked portion in the groove. Each groove has an opening, and the width of the opening is W1 and the width W2 of the necked portion comply with 40%≦W2/W1<1, whereby a high molecular polymer resin can fill each groove and cover the anchoring structure during the packaging process, thereby lifting the metal The bonding force between the component and the polymer resin forms the packaging structure.

Description

Packaging structure and its metal components

The present invention relates to a component of a semiconductor device, in particular to a packaging structure and its metal components.

The existing packaging structure has a lead frame, a semiconductor component and a polymer sealant, wherein the semiconductor component is combined on the lead frame, and the polymer sealant covers the lead frame and the semiconductor component, thereby After completing the packaging of the semiconductor element, the semiconductor element is electrically connected to external electronic components through the lead frame. However, the bonding strength between the polymer sealant and the lead frame is insufficient, so that the polymer sealant and the lead frame of the existing packaging structure are easily separated from each other due to the influence of environmental temperature and humidity.

In view of this, please refer to Figure 16. China's invention patent No. 106471617 provides an existing packaging structure. The packaging structure 90 includes a lead frame 91, a semiconductor component 92, a metal clip 93 and a polymer. Sealing compound 94, in which the lead frame 91 is provided with a plurality of scaly portions 911; the semiconductor element 92 is installed on the lead frame 91 through solder, silver and other joining members; the metal clip 93 connects the semiconductor through joining members The component 92 and the lead frame 91 are used to connect the semiconductor component 92 to external terminals through the lead frame 91; the polymer sealant 94 seals the lead frame 91 and covers the lead frame 91 and the semiconductor component. 92 and the metal clip 93, thereby completing the packaging of the semiconductor element 92.

Furthermore, the scaly portion 911 is processed by a continuous point-shaped laser on the surface of the lead frame 91 to deform the surface of the lead frame 91 to form a scaly three-dimensional structure. Through the scaly portion 911, the surface of the lead frame 91 can be improved. The bonding force between the high molecular polymer sealant 94 and the lead frame 91 .

However, in Chinese invention patent No. 106471617, the inner side of the squamous portion 911 The smooth surface presented does not have better bonding properties; in addition, in order to form the scaly portion 911, the laser is irradiated back and forth in the left and right directions, which easily prevents the metal particles after being irradiated by the laser from being absorbed during the laser irradiation. If completely removed, the bonding property between the scaly portion 911 and the polymer sealant 94 cannot be increased as expected. Therefore, the existing packaging structure 90 still has insufficient bonding force between the polymer resin and the metal components, causing the polymer sealant 94 to easily detach from the lead frame 91 and causing the existing packaging structure 90 to have poor moisture resistance. problems, there are indeed areas that need to be improved.

In order to solve the problem of insufficient bonding force between the polymer resin and the metal component of the existing packaging structure, the purpose of the present invention is to provide a metal component and a packaging structure having the metal component to improve the bonding force between the metal component and the polymer. The bonding force between resins ensures that the encapsulated metal component will not separate from the polymer resin, as further explained below.

The invention provides a metal component, which includes: a plurality of grooves, each of which is linear and has a V-shaped cross-section, so that each of the grooves has two opposite inner sides, and each of the grooves has a V-shaped cross-section. At least one anchoring structure is protruding from the inner surface of at least one, and the at least one anchoring structure forms a necked portion in the groove. Each groove has an opening, and the width W1 of the opening is consistent with the necking. The width W2 of the part complies with 40%≦W2/W1<1.

The invention provides a packaging structure, which includes: at least one metal component as described above; at least one semiconductor device forming an electrical connection with the metal component; and a high molecular polymer resin, the high molecular polymer resin encapsulates The at least one semiconductor device is covered and combined with the metal component, and the high molecular polymer resin extends into a plurality of grooves of the metal component and covers the anchoring structure.

With the above technical features, the present invention forms a plurality of linear grooves on the surface of the metal component through laser processing, and the width W1 of the groove opening is consistent with the width W1 of the necked portion. The width W2 is 40%≦W2/W1<1, so as to improve the bonding force between the metal component and the polymer resin, to solve the problem of separation of the metal component and the polymer resin, and to allow the metal component to be packaged The formed packaging structure has high resistance to moisture sensitivity and can maintain the normal function of electronic components. Therefore, the present invention effectively improves the problems of the existing packaging structure, thereby providing a metal component and a packaging structure having the metal component.

10,10A:Body

101: Adhesive crystal area

11,11A,11C: roughened area

20,20A,20B,20C: Groove

201,201A,201B,201C: opening

202, 202A, 202C: bottom

21,21A,21B,21C: Anchor structure

30A, 30B, 30C: High molecular polymer resin

801:Test piece

802:Packaging plastic

D1: first direction

D2: second direction

H1: Depth from opening to bottom

H2: Depth from neck to opening

P1: first pitch

P2: second pitch

W1: Width of opening

W2: Width of neck part

90:Package structure

91: Lead frame

911: Squamous part

92:Semiconductor components

93:Metal clip

94: High molecular polymer sealant

Figure 1 is a partially enlarged top view of the appearance of a preferred embodiment of the metal component of the present invention.

2A and 2B are side cross-sectional views of the groove of the preferred embodiment of the metal component of the present invention.

3A and 3B are dimensions and schematic diagrams of the metal component of the present invention subjected to thrust testing.

Figure 4 is a distribution diagram of the measured thrust intensity of metal components processed with different laser pitches according to the present invention.

Figure 5 is a photo of a metal component processed with a laser pitch of 250 microns according to the present invention and observed under an optical microscope.

Figures 6 to 9 are scanning electron microscope (SEM) photos of the metal component in Figure 5 at different magnifications.

Figure 10 is a side view cross-sectional SEM photograph of the V-shaped section of the groove of the metal component in Figure 5 after being filled with polymer resin.

Figure 11 is a side view cross-sectional SEM photograph of a metal component processed with a pitch of 500 microns according to the present invention and filled with polymer resin.

Figures 12 to 14 are SEM photos at different magnifications of metal components processed with a pitch of 100 microns according to the present invention.

Figure 15 is a side cross-sectional SEM photograph of the metal component in Figure 12 after being filled with polymer resin.

Figure 16 is a side cross-sectional view of a conventional packaging structure.

In order to understand the technical features and practical effects of the present invention in detail, and to realize them according to the contents of the description, the preferred embodiments shown in the drawings are further described in detail as follows: The present invention provides a metal component, which is used for The preferred embodiment of the semiconductor packaging structure of the metal component is as shown in Figure 1, Figure 2A and Figure 2B, which includes a body 10 and a plurality of grooves 20, wherein the body 10 has a sheet-like structure, and the body There is at least one roughened area 11 on the body 10, and the groove 20 is located on the roughened area 11. The roughened area 11 is used to improve the bonding force between the body 10 and a high molecular polymer resin.

Specifically, the roughened area 11 may cover all or part of the surface of the body 10 . For example, the metal component can be a lead frame. As shown in Figure 1, the surface of the body 10 can be divided into a die-bonding area 101 and a roughened area 11. The die-bonding area 101 is used to set a Semiconductor components, such as Insulated Gate Bipolar Transistor (IGBT), Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), Integrated Circuit (IC) , large-scale integrated circuit (Large-Scale Integration, LSI), etc., the roughened area 11 surrounds the periphery of the die bonding area 101; or, the metal component can also be a metal clip (clip), then the body 10 Part or all of the surface is the roughened area 11, where the metal clip is used to connect a semiconductor component and a pin of a lead frame to allow current to pass, and the metal clip is especially suitable for power semiconductors. packaging structure.

Furthermore, the body 10 can be made of bare copper, and the roughened area 11 is provided on the surface of the bare copper, that is, the plurality of grooves 20 are processed directly on the surface of the bare copper by laser; the body 10 can also be made of a It consists of a base material and a coating layer plated on the surface of the base material. The roughened area 11 is provided on the surface of the coating layer, that is, the plurality of grooves 20 are processed by laser on the surface of the coating layer. When plating, the base material can be a metal material or a non-metal material. The metal material can be copper, for example, and the non-metal material can be ceramic. The plating layer can be a nickel plating or a copper plating, etc.

Please refer to FIG. 1 and FIG. 2A. The plurality of grooves 20 are formed by laser processing to form the roughened area 11. Each groove 20 is linear and has a V-shaped cross-section, so that each groove 20 is linear and has a V-shaped cross-section. The groove 20 has two opposite inner surfaces, an opening 201 and a bottom 202, wherein the bottom 202 is located at the tip of the V-shaped cross section, opposite to the opening 201; at least one inner surface of each groove 20 At least one anchoring structure 21 is protruding, and the at least one anchoring structure 21 forms a necked portion in the groove 20, and the width W1 of the opening 201 and the width W2 of the necked portion conform to 40%≦W2 /W1<1.

In a preferred embodiment of the present invention, discontinuous back-and-forth laser irradiation is used to form the groove 20, but it is not limited to this. The grooves 20 can also be obtained by linear stroke etching using other laser processing methods, that is, each groove 20 can also have a V-shaped cross section, and the anchor is formed on the inner surface of each groove 20 Structural Characteristics of Structure 21.

With the above technical features, when a high molecular polymer resin is formed on the surface of the metal component and combined with the body 10, the high molecular polymer resin will extend into and fill each of the grooves 20 and cover the grooves 20. Covering the anchoring structure 21 makes the high molecular polymer resin closely adhere to the surface of the metal component, and improves the bonding force between the high molecular polymer resin and the metal component.

Please refer to FIG. 2A and FIG. 2B. Two anchoring structures 21 are protruding from the V-shaped cross section of each groove 20. The two anchoring structures 21 are respectively provided on the two inner sides, and the two anchoring structures 21 together form the necking.

If W2/W1<40%, the width W2 of the necked portion is too narrow, and it is difficult for the polymer resin to pass through and fill the groove 20. As a result, the polymer resin cannot completely cover the groove 20. Covering the two anchoring structures 21, the two anchoring structures 21 cannot exert the anchoring effect, resulting in a situation where the polymer resin will still detach from the surface of the metal component, and problems such as the failure of electronic components caused by the existing packaging structure may still occur. . On the other hand, if W2/W1≧1, each groove 20 does not have a V-shaped cross-section, so it is difficult to form the anchoring structure 21, and therefore the anchoring effect cannot be produced to increase the interaction between the polymer resin and the metal member. Bonding power.

Further, please refer to FIG. 2B , the depth H1 between the opening 201 and the bottom 202 and the depth H2 from the necking portion formed between the two anchoring structures 21 to the opening 201 comply with 25%≦H2/H1 ≦60%, in order to produce an anchoring effect that can inhibit the detachment of the polymer resin from the surface of the metal component. When H2/H1>60%, the position of the two anchoring structures 21 is too close to the bottom 202 of the groove 20. Since the groove 20 is V-shaped, the width of the groove 20 is closer to the bottom 202. The narrower the position, the harder it is for the polymer resin to penetrate into the bottom 202 through the constriction. Therefore, it is unfavorable for the polymer resin to fill the groove 20 below the two anchoring structures 21, which will cause There is a problem that the high molecular polymer resin cannot completely cover the two anchoring structures 21 and the two anchoring structures 21 cannot exert the anchoring effect; when H2/H1<25%, the two anchoring structures 21 are formed close to the opening 201 Position, the width of the groove 20 becomes wider closer to the opening 201, so that the width of the necked portion is also relatively wider, resulting in poor anchoring effect on the high molecular polymer resin. Preferably, the depth H1 between the opening 201 and the bottom 202 is greater than 50 microns, so that better results can be obtained.

Please refer to FIG. 1 . A first direction D1 and a second direction D2 intersecting the first direction D1 are defined on at least one roughened area 11 of the body 10 . The plurality of grooves 20 are along the The first direction D1 or the second direction D2 extends, that is, some of the grooves 20 extend linearly along the first direction D1, and other grooves 20 extend linearly along the second direction D2, and Intersect with the groove 20 extending along the first direction D1.

During the process of forming the groove 20 by laser processing, the material of the metal component is partially deformed, thereby forming the bulging anchoring structure 21 on the inner surface of the groove 20, thereby lifting the metal component and The binding force of the high molecular polymer resin.

Further, as shown in FIG. 1 , a first pitch P1 is formed between any two adjacent grooves 20 arranged along the first direction D1, and any two adjacent grooves 20 arranged along the second direction D2 form a first pitch P1. A second pitch P2 is formed between adjacent grooves 20 . Whether adjacent along the first direction D1 or along the second direction D2 is adjacent, and the pitches P1 and P2 formed between any two adjacent grooves 20 are between 100 microns and 1000 microns, inclusive. If the pitches P1 and P2 are greater than 1000 microns, the distance between two adjacent grooves 20 is too large, and it is difficult for laser energy to act in each groove 20 with a larger spacing, making it difficult to form the anchoring structure 21. Therefore, the bonding force between the metal component and the polymer resin cannot be improved; if the pitches P1 and P2 are less than 100 microns and the distance between two adjacent grooves 20 is too small, the laser energy will be too high. The concentration causes the whole to be in a molten state, making the V-shaped shape of the groove 20 or the anchoring structure 21 not obvious. In the preferred embodiment of the present invention shown in FIG. 1 , the first pitch P1 and the second pitch P2 are equal in length.

In order to truly verify the technical efficacy of the present invention, a thrust test was conducted on the metal component sample of the preferred embodiment of the present invention. The implementation of the thrust test was in accordance with the measurement specifications of SEMI-standard (Semiconductor Standard) G69-0996. In this specification, the adhesion strength measurement specification between the packaging material epoxy resin (epoxy molding compound, EMC; that is, the polymer resin) and the lead frame is specified, including the shear method (Shear Method). ), Pull Method and Three-Pont Bending Method, each of which has standard test piece 801 size, packaging plastic 802 size and measurement method. The thrust test of the present invention adopts the shear force method, as shown in Figure 3A, Figure 3B and Table 1. The size of the test piece 801 and the size of the packaging plastic 802.

The above-mentioned packaging plastic 802 is made of Nitto GE-1030L epoxy resin. At a temperature of 175°C, the packaging plastic 802 is pre-cured for 6 hours. Further, using the pitches P1 and P2 as variables, the plurality of grooves 20 are formed on the metal member at different pitches P1 and P2 to prepare the test piece 801, and through the shear force method, as shown in the figure As shown in 3B, push the test piece 801 horizontally to test the test piece 801 and the package. The bonding strength of plastic 802. Please refer to Figure 4 and Table 2. Each point in Figure 4 represents the data obtained from 25 to 36 tests of the test piece 801 made with the corresponding pitches P1 and P2 processed by different laser pitches. The average value, and the average intensity in Table 2, while the upper and lower leads of each point in Figure 4 represent the distribution of values within the 95% confidence interval. Furthermore, the formation ratio of the anchor structure 21 in Table 2 represents the ratio of forming the anchor structure 21 at 10 positions sampled on the groove 20 formed according to the corresponding pitches P1 and P2. , for example, 6/10 means that at least one of the anchoring structures 21 is formed at 6 of the 10 positions, and has the structural characteristics of the necking portion.

As shown in Table 2, when the pitches P1 and P2 are between 100 microns and 500 microns (inclusive), the proportion of the anchoring structures 21 formed in each groove 20 is relatively high, which can provide higher The bonding strength, for example, is shown in Table 2. When the pitches P1 and P2 are between 100 microns and 500 microns, the tested strengths are all greater than 16.5 kilograms of force. It can be seen from Table 2 and Figure 4 that when the test piece 801 has the anchoring structure 21, the bonding strength between the test piece 801 and the packaging plastic 802 is between 13 and 35 kilograms of force, which is better than that of bare copper or that the groove 20 has Test piece 801 with pitches P1 and P2 greater than 1000 microns.

Further, as shown in Table 2, the smaller the pitches P1 and P2 are, the smaller the ratio of W2/W1 will be. In other words, compared with the same width W1 of the opening 201, as the pitches P1, P2 are smaller, the ratio of W2/W1 will be smaller. The smaller P2 is, the longer the anchoring structure 21 is, so that the width W2 of the necked portion of the groove 20 is smaller. In this way, when the high molecular polymer resin fills the groove 20, the necking portion can provide higher bonding force.

Preferably, when the width W1 of the opening 201 and the width W2 of the necked portion comply with 50%≦W2/W1≦75%, each groove 20, each anchor structure 21 and the necked portion can be Produce better anchoring effect.

Preferably, when the depth H1 between the opening 201 and the bottom 202 and the depth H2 from the necking part to the opening 201 comply with 40%≦H2/H1≦55%, each groove 20, each The anchoring structure 21 and the necking portion can produce a better anchoring effect.

When the pitches P1 and P2 are 250 microns respectively, the roughened area 11A of the metal component is as shown in FIG. 5 , because the first pitch P1 and the second pitch P2 are equal, and the third pitch P1 is equal to the second pitch P2. One direction D1 intersects the second direction D2, so that the plurality of grooves 20A form a rhombus pattern on the surface of the body 10A; and when the first direction D1 and the second direction D2 are perpendicular to each other, the plurality of grooves 20A A square pattern will form. Further, please refer to FIGS. 6 and 7 , the plurality of grooves 20A are staggeredly recessed in the roughened area 11A, and as shown in FIGS. 8 to 10 , both inner sides of the grooves 20A are A V-shape is formed, and the top of the V-shape forms the opening 201A, and the bottom of the groove 20A forms the bottom 202A. As shown in FIG. 10 , the groove 20A forms two anchoring structures 21A in a partial area.

Please refer to Figure 10. The present invention also provides a packaging structure. The packaging structure The metal component as shown in Figures 1, 5 and 6 is formed after encapsulation. The packaging structure further includes at least one semiconductor device and a polymer resin 30A. The semiconductor device and the metal component Form an electrical connection; the polymer resin 30A is molded and combined with the metal component, and the polymer resin 30A extends into a plurality of grooves 20A of the metal component and covers the anchoring structure 21A. As shown in FIG. 10 , the high molecular polymer resin 30A fills the groove 20A. In this way, when the packaging structure is subjected to external force or stress, since the high molecular polymer resin 30A fills the groove 20A and covers the anchoring structure 21A, there is an anchoring effect between it and the metal component. The high bonding force can effectively prevent the polymer resin 30A from being detached from the metal component, thereby improving the moisture resistance of the packaging structure and effectively reducing the failure of electronic components. The metal component in the package structure of the present invention is illustrated by taking the pitch P1 and P2 of the grooves 20A in FIGS. 5 and 6 as 250 microns as an example. However, the metal component in the package structure of the present invention is not limited thereto. In addition, the metal component with the groove 20A in the packaging structure of the present invention can be a lead frame or a metal clip; or, the packaging structure of the present invention can also include two metal components, serving as a lead frame and a metal clip respectively. Metal clip.

Please refer to Figure 11. When the pitches P1 and P2 of the metal component of the package structure are 500 microns respectively, the cross section of the groove 20B is still V-shaped, and the two sides of the groove 20B are still V-shaped. The two anchoring structures 21B are still formed in the middle section of the inner side to provide the anchoring effect of the high molecular polymer resin 30B and solve the problem to be solved in this case.

Furthermore, compared with the surface of the metal component as shown in Figures 6 to 9, please refer to Figures 12 to 14, when the pitches P1 and P2 of the metal component of the present invention are 100 microns respectively, During the laser etching process, more metal materials are melted and deposited on the surface of the roughened area 11C, which can further increase the surface roughness of the roughened area 11C, thereby improving the polymer resin. anchoring effect. In addition, as shown in Figure 15, in the cross-section of the metal component after being filled with the polymer resin 30C, it can be clearly seen that each groove 20C has a V-shaped cross-section, and in the opening 201C Two opposite anchoring structures 21C are formed on both inner surfaces of the position between the bottom 202C and the bottom 202C. Therefore, after the high molecular polymer resin 30C fills the groove 20C, it can create a higher level with the metal component. The bonding force can improve the moisture resistance of the packaging structure, effectively reducing the failure of electronic components.

With the above technical features, the present invention forms a plurality of linear grooves 20, 20A, 20B, and 20C on the surface of the metal component through laser etching processing, and when 40%≦W2/W1<1 In the case of , at least one of the anchoring structures 21, 21A, 21B, 21C is protruding from at least one inner surface of the grooves 20, 20A, 20B, 20C, where the grooves 20, 20A, 20B, The necking portion is formed in 20C to improve the bonding force between the metal component and the polymer resin 30A, 30B, and 30C, thereby solving the problem of separation of the metal component and the polymer resin 30A, 30B, and 30C, and allowing The encapsulation structure formed after encapsulation of the metal component has high resistance to moisture sensitivity and can maintain the normal function of the electronic component. Therefore, the present invention effectively improves the problems of the existing packaging structure, thereby providing a metal component and a packaging structure having the metal component.

The above are only preferred embodiments of the present invention and do not limit the present invention in any form. Anyone with ordinary knowledge in the technical field can utilize the present invention without departing from the scope of the technical solution proposed by the present invention. Equivalent embodiments with partial changes or modifications to the disclosed technical content without departing from the technical content of the present invention are still within the scope of the technical solution of the present invention.

20:Gutter

201:Open your mouth

21:Anchor structure

W1: Width of opening

W2: Width of neck part

Claims (10)

A metal component, which includes: A plurality of grooves, each groove is linear and has a V-shaped cross-section, so that each groove has two opposite inner sides, and at least one anchoring structure is protruding from at least one inner side of each groove. , the at least one anchoring structure forms a necked portion in the groove, each groove has an opening, and the width W1 of the opening and the width W2 of the necked portion comply with 40%≦W2/W1<1 . The metal member as claimed in claim 1, wherein two of the anchoring structures are protruding from the V-shaped section of each groove, the two anchoring structures are respectively provided on the two inner sides, and the two anchoring structures together form the neck. Shrinkage. The metal member as claimed in claim 1, wherein the width W1 of the opening and the width W2 of the necked portion comply with 50%≦W2/W1≦75%. The metal component as claimed in claim 1, wherein each groove has a bottom, and the depth H1 from the opening to the bottom and the depth H2 from the necking portion to the opening comply with 25%≦H2/H1≦60% . The metal member as claimed in claim 4, wherein the depth H1 between the opening and the bottom and the depth H2 from the necking part to the opening comply with 40%≦H2/H1≦55%. The metal component according to claim 1, wherein a pitch is formed between any two adjacent grooves, and the pitch is between 100 microns and 1000 microns, inclusive. The metal component of claim 6, wherein the pitch is between 100 microns and 500 microns, inclusive. The metal component as claimed in any one of claims 1 to 7, wherein the metal component is a lead frame. The metal component according to any one of claims 1 to 7, wherein the metal component is a metal clip. A packaging structure, which includes: At least one metal component as described in any one of claims 1 to 9; At least one semiconductor device forms an electrical connection with the metal member; and A high molecular polymer resin, the high molecular polymer resin covers the at least one semiconductor device and is combined with the metal component, and the high molecular polymer resin extends into a plurality of grooves of the metal component and covers Cover the anchoring structure.