Molded semiconductor package with C-wing leads and gull-wing leads

Abstract

A semiconductor package includes a semiconductor die embedded in a molded package body; leads electrically connected to the die and extending from a first side of the molded package body; and a recess extending inwardly from the side and into a bottom major surface of the molded package body to form a single recess. The recess begins below the area of ​​the side from which the leads extend, so that this area of ​​the side is flat and each lead exits the molded package body in the same plane. A first subset of the leads bends inwardly toward the molded package body and is located in the single recess to form a first row of leads configured for surface mounting. A second subset of the leads extends outwardly from the molded package body to form a second row of leads configured for surface mounting.

Description

Technical Field

[0001] The present application relates to molded semiconductor packages, and in particular to molded semiconductor packages having C-wing leads. Background Art

[0002] Molded semiconductor packages are widely used in many industries as a low-cost packaging solution for semiconductor components. Molded semiconductor packages are available in a variety of forms, including leaded options and leadless options. Leaded packages have metal leads extending from the sides of the molded body. The shape of the leads can be like the letter J (so-called J-wing leads), the leads can be gull-wing leads, C-wing leads shaped like the letter C, and the like. The leads are usually soldered to a carrier such as a printed circuit board (PCB). With the growth of the trend towards miniaturization of packages, metal routing on the carrier for contacting the package leads has become more challenging.

[0003] Therefore, there is a need for a molded semiconductor package having a more efficient lead arrangement. Summary of the invention

[0004] According to an embodiment of a semiconductor package, the semiconductor package includes: a molded package body having a bottom main face, a top main face, and a side face extending from the bottom main face to the top main face; a semiconductor die embedded in the molded package body; a first plurality of leads electrically connected to the semiconductor die and extending from a first side face of the molded package body; and a first recess extending inwardly from the first side face of the molded package body and into the bottom main face to form a single groove along the first side face at the bottom of the package. The first recess begins below an area of ​​the first side face from which the first plurality of leads extend, so that an area of ​​the first side face from which the first plurality of leads extend is flat, and all of the leads in the first plurality of leads leave the molded package body in the same plane. A first subset of the first plurality of leads bends inwardly toward the molded package body and is located in a single groove formed by the first recess to form a first row of leads configured for surface mounting. A second subset of the first plurality of leads extends outwardly from the molded package body to form a second row of leads configured for surface mounting.

[0005] Those skilled in the art will recognize additional features and advantages upon reading the following detailed description, and upon viewing the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The elements in the drawings are not necessarily drawn to scale relative to each other. Similar reference numerals represent corresponding similar parts. The features of the various illustrated embodiments may be combined unless they are mutually exclusive. The embodiments are illustrated in the drawings and are described in detail in the following description.

[0007] Figure 1 A top perspective view of an embodiment of a molded semiconductor package is shown having staggered C-wing leads and gull-wing leads on one or more sides of the package.

[0008] Figure 2 A top perspective view of a molded semiconductor package is shown without a molded package body.

[0009] Figure 3 A top perspective view of one corner area of ​​the molded semiconductor package 100 during lead processing is shown.

[0010] Figure 4 Shows Figure 3 Bottom perspective view of the corner area shown in .

[0011] Figure 5 Shows Figure 3 0014] A side view of a corner area of ​​a molded semiconductor package is shown in FIG.

[0012] Figure 6 Shows Figure 3 Bottom view of the corner area shown in .

[0013] Figure 7 A partial side view of a molded semiconductor package after attachment to a carrier is shown.

[0014] Figure 8 A partial side view of a molded semiconductor package after attachment to a carrier according to another embodiment is shown. DETAILED DESCRIPTION

[0015] Embodiments described herein provide a molded semiconductor package having staggered C-wing leads and gull-wing leads on one or more sides of the package, wherein the C-wing leads are bent inwardly and are located in a single groove formed in each side of the molded package body at the bottom of the package body having the leads. The C-wing leads form a first row of leads configured for surface mounting, and the gull-wing leads form a second row of leads configured for surface mounting. The spacing between the two rows of different lead types can be selected to reduce the design constraints of the metal wiring on the carrier to which the molded semiconductor package is to be attached, thereby allowing the package to be miniaturized. In addition, by staggering the C-wing leads and the gull-wing leads, a smaller molded package body and footprint can be achieved, which reduces the cost of each package and improves process efficiency by performing higher density / strip processing and testing in the process flow.

[0016] Figure 1A top perspective view of an embodiment of a molded semiconductor package 100 is shown having staggered C-wing leads 102 and gull-wing leads 104, wherein the C-wing leads 102 are bent inwardly and positioned in a single groove formed in each side 106a-106d of a molded package body 108 at a bottom 110 of the package 100.

[0017] Figure 2 The molded semiconductor package 100 is shown without a molded package body 108 (ie, before molding).

[0018] Figure 3 A top perspective view of one corner area of ​​the semiconductor package 100 molded during lead processing is shown.

[0019] Figure 4 Shows Figure 3 Bottom perspective view of the corner area shown in .

[0020] The molded package body 108 of the molded semiconductor package 100 has a bottom main surface 112a, a top main surface 112b, and side surfaces 106a-106d extending from the bottom main surface 112a to the top main surface 112b. The molded package body 108 may include any standard composite material used for semiconductor package molding, such as epoxy resin, phenolic curing agent, silicon dioxide, catalyst, pigment, release agent, etc. The type of molding compound depends on the type of package, such as, thick, thin, low power, high power, etc. The molded package body 108 can be manufactured by any standard molding method such as injection molding, transfer molding, vacuum forming, etc. The shape and surface features of the molded package body 108 correspond to the design of the mold die or mold cavity used in the molding process.

[0021] The molded semiconductor package 100 also includes at least one semiconductor die 114 embedded in the molded package body 108. For ease of illustration, Figure 2100 , a single die is shown, however the molded semiconductor package 100 may include more than one die embedded in the molded package body 108. Some of the semiconductor dies embedded in the molded package body 108 may include one or more power semiconductor devices, such as power MOSFETs, IGBTs, BJTs, thyristors, JFETs, diodes, etc. Some of the semiconductor dies embedded in the molded package body 108 may include logic devices such as processors, controllers, ASICs (application specific integrated circuits), etc. Some of the semiconductor dies embedded in the molded package body 108 may include memory devices such as volatile or non-volatile memories. Some of the semiconductor dies embedded in the molded package body 108 may be passive dies, such as capacitor dies and / or inductor dies. Each semiconductor die may be made of any type of semiconductor material, such as single element semiconductors (e.g., Si, Ge, etc.), silicon-on-insulator semiconductors, binary semiconductors (e.g., SiC, GaN, GaAs, etc.), ternary semiconductors, etc., with or without (one or more) epitaxial layers.

[0022] C-wing leads 102 and gull-wing leads 104 are electrically connected to the semiconductor die and extend from sides 106a-106d of molded package body 108. In some embodiments, the leads may not extend from all sides 106a-106d of molded semiconductor package 100. Figure 1-4 The configuration of 16 leads per side shown in is intended as a non-limiting example. In general, any number of C-wing leads 102 and gull-wing leads 104 may extend from one or more sides 106a-106d of the molded semiconductor package 100. For example, instead of Figure 1-4 Instead of the 64 lead example shown in , molded semiconductor package 100 may alternatively have a total of 48 leads (24 C-wing leads 102 and 24 gull-wing leads 104), a total of 176 leads (88 C-wing leads 102 and 88 gull-wing leads 104), or more or less total lead count.

[0023] The leads 102, 104 may be metal tabs of a lead frame 116. The lead frame 116 also includes pads 118 to which the semiconductor die 114 is attached. The bottom side of the semiconductor die 114 may form a terminal of the die 114 in the case of a vertical device, or there may be no terminals in the case of a lateral device. Any standard lead frame may be used to implement the die pads 118 and the leads 102, 104. The internal electrical connections between the semiconductor die 114 and the leads 102, 104 embedded in the molded package body 108 may be implemented as wire bonds, metal clips, metal straps, etc. For ease of illustration, the internal electrical connections are not shown in the figures.

[0024] Recesses 120a-120d are formed in each respective side 106a-106d of the molded package body 108 from which the leads 102, 104 extend. Each recess 120a-120d extends inwardly from the respective side 106a-106d of the molded package body 108 and into the bottom major surface 112a of the molded package body 108 to form a single groove (notch) 122a-122d along the side 106a-106d at the bottom 110 of the package 100. Each groove 122a-122d extends the entire length of the side 106a-106d in which the groove is formed, except in the corner areas where there are no leads 102, 104. Each recess 120a-120d is formed in the molded package body 108. Figure 1 120a - 120d are shown in dashed boxes in the top perspective view because the recesses 120a - 120d are hidden in this view. Figure 2 The recesses 120a-120d are not shown in FIG. Figure 2 The molded semiconductor package 100 is shown without the molded package body 108. Figure 4 The illustrated corner region shows respective single grooves 122a, 122b formed in two adjacent sides 106a, 106b of the molded package body 108, and Figure 3 The same corner area is shown, but in a top perspective view.

[0025] exist Figure 3 and Figure 4 During this stage of the manufacturing process shown, the leads 102, 104 on one side 106b of the molded package body 108 have not yet been trimmed, and the leads 102, 104 are connected by tie bars 124 of the lead frame 116. The tie bars 124 are removed later in the process in the corner area, and the bars 124 are cut between the leads 102, 104. Some of the leads 102, 104 extending from the adjacent side 106a of the molded package body 108 are shown as being trimmed and flush with the side 106a. In reality, these leads 102, 104 are not trimmed flush with the side 106a of the molded package body 108, but rather are trimmed as shown. Figure 1 and Figure 2 An alternating array of C-wing leads 102 and gull-wing leads 104 is shown extending from a molded package body 108 . Figure 3 and Figure 4 The leads 102 , 104 trimmed flush with the side 106 a are shown in this manner solely to better illustrate the placement of a single C-wing lead 102 in a single groove 122 a formed along the corresponding side 106 a of the molded package body 108 at the bottom 110 of the package 100 .

[0026] Each recess 120a-120d forming a single groove 122a-122d at the bottom 110 of the package 100 begins below the area 126a-126d of the corresponding side 106a-106d from which the leads 102, 104 extend, so that the area 126a-126d of each side 106a-106d from which a group of leads 102, 104 extend is flat and all the leads 102, 104 exit the molded package body 108 in the same plane at that side 106a-106d. The C-wing leads 102 exiting the molded package body 108 at the same side 106a-106d bend inwardly toward the molded package body 108 and are located in the same single groove 122a-122d formed by the recess 120a-120d in that side 106a-106d to form a first row of leads configured for surface mounting. Gull-wing leads 104 , which are interleaved with C-wing leads 102 and exit the molded package body 108 at the same sides 106 a - 106 d , extend outwardly from the molded package body 108 to form a second row of leads also configured for surface mounting.

[0027] exist Figures 1 to 4 In the illustrated embodiment, the groups of staggered C-wing leads 102 and gull-wing leads 104 extend from all sides 106a-106d of the molded package body 108. Thus, each side 106a-106d of the molded package body 108 has a recess 120a-120d as described above, which forms a single groove 122a-122d at the bottom 110 of the package 100 for receiving the C-wing leads 102 extending from that side 106a-106d of the molded package body 108. However, as also described above, the leads may not extend from some of the sides 106a-106d of the molded package body 108. For these molded semiconductor packages, a recess 120x and a corresponding single groove 122x are formed only along each side 106x of the molded package body 108 from which the staggered C-wing leads 102 and gull-wing leads 104 extend. Thus, only the sides 106a-106d of the molded package body 108 from which one set of leads 102, 104 exit have a single groove configuration for receiving a corresponding C-wing lead 102. Typically, the total number of grooves 122x formed at the bottom 110 of the package 100 corresponds to the number of sides 106x of the molded package body 108 from which the staggered C-wing leads 102 and gull-wing leads 104 extend.

[0028] exist Figures 1 to 4In the illustrated embodiment, a first group of staggered C-wing leads 102 and gull-wing leads 104 extend from a first side 106 a of the molded package body 108, a second group of staggered C-wing leads 102 and gull-wing leads 104 extend from a second side 106 b of the molded package body 108 adjacent to the first side 106 a, a third group of staggered C-wing leads 102 and gull-wing leads 104 extend from a third side 106 c of the molded package body 108 adjacent to the second side 106 b, and a fourth group of staggered C-wing leads 102 and gull-wing leads 104 extend from a fourth side 106 d of the molded package body 108, the fourth side 106 d being adjacent to the third side 106 c at a first end and adjacent to the first side 106 a at a second end. All four sides 106a-106d of the molded package body 108 have recesses 120a-120d extending inwardly from the respective side 106a-106d and into the bottom major surface 112a to form a single groove 122a-122d along that side 106a-106d at the bottom 110 of the package 100. Each recess 120a-120d begins below a region 126a-126d of the side 106a-106d from which a respective set of leads 102, 104 extend, such that that region 126a-126d of the side 106a-106d is planar and all of the leads 102, 104 exit the molded package body 108 in the same plane at that side 106a-106d of the molded package body 108. In each group of leads 102, 104, a first subset of the leads 102, 104 bends inwardly toward the molded package body 108 and is positioned in a single groove 122a-122d formed by the corresponding recesses 120a-120d to form a row of C-wing leads 102 configured for surface mounting. A second subset of the leads 102, 104 in each group extends outwardly from the molded package body 108 and is shaped to form a row of gull-wing leads 104 also configured for surface mounting.

[0029] Figure 5 Shows Figure 3 0014] A side view of a corner area of ​​a molded semiconductor package is shown in FIG.

[0030] Figure 6 Shows Figure 3 Bottom view of the corner area shown in .

[0031] Each C-wing lead 102 has a defined thickness t_lead, and a single groove 122a-122d in which all C-wing leads 102 extend from the same side 106a-106d of the molded package body 108 has a depth d_groove, such as Figure 5As shown. The depth d_groove of the individual grooves 122a-122d is measured in the direction x perpendicular to the bottom main surface 112a of the molded package body 108. In one embodiment, the thickness t_lead of a row of C-shaped wing leads 102 located in the individual grooves 122a-122d is greater than the depth d_groove of the individual grooves 122a-122d, so that the row of C-shaped wing leads 102 is not flush with the bottom main surface 112a of the molded package body 108, as shown. Figure 5 As shown. According to this embodiment, the bottom of each C-wing lead 102 protrudes (extends) beyond the bottom 110 of the package 100 to provide a positive standoff for subsequent mounting to a carrier. Additionally or alternatively, a row of C-wing leads 102 can be spaced apart from the top major surface 128 of a single groove 122a-122d by a distance h_offset, for example, about 0.05 mm or more. According to this embodiment, a row of C-wing leads 102 is located in a single groove 122a-122d, but does not contact the top major surface 128 of the groove 122a-122d. Alternatively, some or all of the C-wing leads 102 can contact the top major surface 128 of the groove 122a-122d.

[0032] A row of C-wing leads 102 in the same groove 122a-122d may be spaced apart from the rear sidewall 130 of the groove 122a-122d by a minimum distance s_min1, for example, about 0.06 mm or more. Figure 6 The two endmost C-wing leads 102 may be spaced apart from the adjacent lateral sidewalls 132 of the corresponding slots 122a-122d by a minimum distance s_min2, for example, about 0.1 mm or more, as shown in FIG. Figure 6 shown.

[0033] The recesses 120x, 120y formed in the adjacent side surfaces 106x, 106y of the molded package body 108 may terminate before reaching the corner region 134 connecting the adjacent side surfaces 106x, 106y of the molded package body 108, such that the recesses 120x, 120y are spaced apart from each other and the bottom 110 of the package 100 is not recessed in the corner region 134. In one embodiment, in the connecting corner region 134, the recesses 120a-120d formed in the adjacent side surfaces 106a-106d of the molded package body 108 may be spaced apart from each other by a minimum distance c_space of at least 0.5 mm, as shown in FIG. Figure 6 shown.

[0034] Figure 7A partial side view of a molded semiconductor package 100 after being attached to a carrier 200 such as a PCB is shown. The carrier 200 includes metal contact areas 202 connected to corresponding leads 102, 104 of the molded semiconductor package 100 by bonding materials 204 such as solder, and an insulating layer 206 for spacing the metal contact areas 202. Each metal contact area 202 has a total minimum width of the contact area for the corresponding lead 102 / 104, and an additional minimum space s1, s2 on each side of the lead contact area for accommodating the bonding material 204. Adjacent metal contact areas 202 on the carrier 200 are spaced apart by a minimum distance s3. Based on this configuration of the contact area spacing on the carrier 200, a row of C-wing leads 102 and a row of gull-wing leads 104 extending from the same side 106a-106d of the molded package body 108 are spaced apart from each other by a minimum distance d_rows=s3+2*s2. In one embodiment, a minimum distance d_rows between a row of C-wing leads 102 and a row of gull-wing leads 104 extending from the same side 106a - 106d of the molded package body 108 is at least 0.8 mm.

[0035] Figure 8 A partial side view of a molded semiconductor package 100 after being attached to a carrier 200 according to another embodiment is shown. Figure 8 The embodiment shown in is similar to Figure 7 . However, the difference is that the single groove 122a-122d where the entire row of C-wing leads 102 is located has an angled major surface 300 that faces the row of C-wing leads 102 and is inclined inwardly. In one embodiment, the angled major surface 300 of the grooves 122a-122d is inclined inwardly at an angle between 10 degrees and 20 degrees relative to the bottom major surface 112a of the molded package body 108.

[0036] Spatially relative terms such as "below," "below," "lower," "above," "on," etc. are used for ease of description to explain the position of one element relative to a second element. These terms are intended to cover different orientations of the device in addition to orientations different from those shown in the figures. In addition, terms such as "first," "second," etc. are also used to describe various elements, regions, parts, etc., and these terms are not intended to be limiting. Similar terms refer to similar elements throughout the specification.

[0037] As used herein, the terms "having", "containing", "including", "comprising", etc. are open terms that indicate the presence of stated elements or features, but do not exclude other elements or features. Unless the context clearly indicates otherwise, the articles "a", "an", and "the" are intended to include the plural as well as the singular.

[0038] In view of the above range of variations and applications, it should be understood that the present invention is not limited by the foregoing description, nor by the accompanying drawings. Instead, the present invention is limited only by the following claims and their legal equivalents.

Claims

1. A semiconductor package, comprising: a molded package body having a bottom main surface, a top main surface, and side surfaces extending from the bottom main surface to the top main surface, a semiconductor die embedded in the molded package body; a first plurality of leads electrically connected to the semiconductor die and extending from a first side of the molded package body; as well as a first recess extending inwardly from the first side of the molded package body and into the bottom major surface to form a single groove along the first side at the bottom of the package, wherein the first recess begins below an area of ​​the first side from which the first plurality of leads extend, such that the area of ​​the first side from which the first plurality of leads extend is flat and all of the first plurality of leads exit the molded package body in the same plane, wherein a first subset of the first plurality of leads bends inwardly toward the molded package body and is located in the single groove formed by the first recess to form a first row of leads configured for surface mounting, Wherein a second subset of the first plurality of leads extends outwardly from the molded package body to form a second row of leads configured for surface mounting.

2. The semiconductor package according to claim 1, wherein The first row of leads is spaced apart from the second row of leads by a minimum distance of at least 0.8 mm.

3. The semiconductor package according to claim 1, wherein: The thickness of the first row of leads located in the single groove formed by the first recess is greater than the depth of the single groove, so that the first row of leads is not flush with the bottom main surface of the molded package body, and wherein the depth of the single groove is measured in a direction perpendicular to the bottom main surface.

4. The semiconductor package according to claim 1, further comprising: a second plurality of leads electrically connected to the semiconductor die and extending from a second side of the molded package body adjacent to the first side; as well as a second recess extending inwardly from the second side surface of the molded package body and into the bottom major surface to form a single groove along the second side surface at the bottom of the package, wherein the second recess begins below an area of ​​the second side from which the second plurality of leads extend, such that the area of ​​the second side from which the second plurality of leads extend is flat and all of the second plurality of leads exit the molded package body in the same plane, wherein a first subset of the second plurality of leads bends inwardly toward the molded package body and is located in the single groove formed by the second recess to form a third row of leads configured for surface mounting, Wherein a second subset of the second plurality of leads extends outwardly from the molded package body to form a fourth row of leads configured for surface mounting.

5. The semiconductor package according to claim 4, wherein: The third row of leads is spaced apart from the fourth row of leads by a minimum distance of at least 0.8 mm.

6. The semiconductor package according to claim 4, wherein: The thickness of the third row of leads located in the single groove formed by the second recess is greater than the depth of the single groove, so that the third row of leads is not flush with the bottom main surface of the molded package body, and wherein the depth of the single groove is measured in a direction perpendicular to the bottom main surface.

7. The semiconductor package according to claim 4, wherein: The first recess and the second recess both terminate before reaching a corner region of the molded package body connecting the first side surface to the second side surface, so that the bottom of the package is not recessed in the corner region.

8. The semiconductor package according to claim 7, wherein: In the corner region, the first recess is spaced apart from the second recess by a minimum distance of at least 0.5 mm.

9. The semiconductor package according to claim 6, further comprising: a third plurality of leads electrically connected to the semiconductor die and extending from a third side of the molded package body adjacent to the second side; as well as a third recess extending inwardly from the third side of the molded package body and into the bottom main surface to form a single groove along the third side at the bottom of the package, wherein the third recess begins below an area of ​​the third side from which the third plurality of leads extend, such that the area of ​​the third side from which the third plurality of leads extend is flat and all of the third plurality of leads exit the molded package body in the same plane, wherein a first subset of the third plurality of leads bends inwardly toward the molded package body and is located in the single groove formed by the third recess to form a fifth row of leads configured for surface mounting, Wherein a second subset of the third plurality of leads extends outwardly from the molded package body to form a sixth row of leads configured for surface mounting.

10. The semiconductor package according to claim 9, wherein The fifth row of leads is spaced apart from the sixth row of leads by a minimum distance of at least 0.8 mm.

11. The semiconductor package according to claim 9, wherein: The thickness of the fifth row of leads located in the single groove formed by the third recess is greater than the depth of the single groove, so that the fifth row of leads is not flush with the bottom main surface of the molded package body, and wherein the depth of the single groove is measured in a direction perpendicular to the bottom main surface.

12. The semiconductor package according to claim 9, wherein: The second recess and the third recess both terminate before reaching a corner region of the molded package body connecting the second side surface to the third side surface, so that the bottom of the package is not recessed in the corner region.

13. The semiconductor package according to claim 12, wherein: In the corner region, the second recess is spaced apart from the third recess by a minimum distance of at least 0.5 mm.

14. The semiconductor package according to claim 9, further comprising: a fourth plurality of leads electrically connected to the semiconductor die and extending from a fourth side of the molded package body, the fourth side adjacent to the third side at a first end and adjacent to the first side at a second end; as well as a fourth recess extending inwardly from the fourth side of the molded package body and into the bottom main surface to form a single groove along the fourth side at the bottom of the package, wherein the fourth recess begins below an area of ​​the fourth side from which the fourth plurality of leads extend, such that the area of ​​the fourth side from which the fourth plurality of leads extend is flat and all of the fourth plurality of leads exit the molded package body in the same plane, wherein a first subset of the fourth plurality of leads bends inwardly toward the molded package body and is located in the single groove formed by the fourth recess to form a seventh row of leads configured for surface mounting, Wherein a second subset of the fourth plurality of leads extends outwardly from the molded package body to form an eighth row of leads configured for surface mounting.

15. The semiconductor package according to claim 14, wherein: The seventh row of leads is spaced apart from the eighth row of leads by a minimum distance of at least 0.8 mm.

16. The semiconductor package according to claim 14, wherein: The thickness of the seventh row of leads located in the single groove formed by the fourth recess is greater than the depth of the single groove, so that the seventh row of leads is not flush with the bottom main surface of the molded package body, and wherein the depth of the single groove is measured in a direction perpendicular to the bottom main surface.

17. The semiconductor package according to claim 14, wherein: The third recess and the fourth recess both terminate before reaching a corner region of the molded package body connecting the third side surface to the fourth side surface, so that the bottom of the package is not recessed in the corner region.

18. The semiconductor package according to claim 17, wherein: In the corner region, the third recess is spaced apart from the fourth recess by a minimum distance of at least 0.5 mm.

19. The semiconductor package according to claim 1, wherein: The single groove formed along the first side at the bottom of the package has an angled major surface that faces the first row of leads and slopes inwardly.

20. The semiconductor package according to claim 19, wherein The angled major surface of the single groove is inclined inwardly at an angle between 10 degrees and 20 degrees relative to the bottom major surface of the molded package body.

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