Semiconductor package with partially plated lead

Abstract

A semiconductor package includes a lead frame, a chip, and a molded package. The lead frame includes one or more die pads and a plurality of leads. Each of the plurality of leads includes a base member and a protruding member. The width of the end face of the protruding member of each of the plurality of leads is less than 50% of the width of the respective base member in order to improve solderability. A method for manufacturing a semiconductor package includes the steps of providing an array of lead frames, mounting a chip, forming a molded package, applying a dicing or stamping process, applying a plating process, and applying a singulation process.

Description

Technical Field

[0001] The present invention generally relates to a semiconductor package having a plurality of leads with partially plated sides and a method for manufacturing the same. More particularly, the present invention relates to a semiconductor package manufactured using a lead frame including barrier bars and grooves. Background Art

[0002] Conventional quad flat no-lead and dual flat no-lead lead packages contain copper exposed on the wire end surfaces after the cutting or stamping process. This exposed copper oxidizes over time. The oxidized copper end surfaces degrade the solder connection quality.

[0003] The present invention provides a solution by introducing barrier bars and multiple grooves in a lead frame to form multiple leads with a wettable area exceeding 50% at the end region and to form multiple leads on two opposite side surfaces of each lead. Summary of the Invention

[0004] An object of the present invention is to provide a semiconductor package having partially plated lead sides and a method for manufacturing the same.

[0005] To achieve the above object, the present invention provides a semiconductor package comprising:

[0006] A lead frame comprising:

[0007] one or more die pads; and

[0008] A first plurality of leads extends from the one or more die pads along a first direction, each lead of the first plurality of leads comprising:

[0009] A base member comprising:

[0010] a first side; and

[0011] a second side; and

[0012] a protruding member directly connected to the base member of the first plurality of leads, the protruding member of the first plurality of leads comprising:

[0013] One end face;

[0014] a chip attached to one or more die pads on a lead frame;

[0015] and a molded package encapsulating the chip;

[0016] wherein the end face width of the protruding member of each lead of the first plurality of leads is less than 50% of the width of the base member of each lead of the first plurality of leads; and

[0017] The end surface of the protruding member of each lead in the first plurality of leads is not plated with a wettable metal for soldering.

[0018] Optionally, more than 50% of the first side surface of the base member of each of the first plurality of leads and more than 50% of the second side surface of the base member of each of the first plurality of leads are plated with a wettable metal for soldering.

[0019] Optionally, each lead in the first plurality of leads further comprises:

[0020] a first notch located between a first side surface of the base member of each of the first plurality of leads and an end surface of the protruding member of each of the first plurality of leads; and

[0021] a second notch located between the second side surface of the base member of each of the first plurality of leads and an end surface of the protruding member of each of the first plurality of leads; and

[0022] Wherein, a surface of the first notch of each lead in the first plurality of leads and a surface of the second notch of each lead in the first plurality of leads are plated with a wettable metal for welding.

[0023] Optionally, the protruding member of each lead of the first plurality of leads further comprises:

[0024] a first planar side surface; and

[0025] a second flat side surface opposite to the first flat side surface;

[0026] wherein the base member of each lead of the first plurality of leads further comprises:

[0027] a first planar end surface perpendicular to and directly connected to the first side surface of the base member of each of the first plurality of leads; and

[0028] a second planar end surface perpendicular to and directly connected to the second side surface of the base member of each of the first plurality of leads;

[0029] wherein a first flat side surface of the protruding member of each lead in the first plurality of leads, a second flat side surface of the protruding member of each lead in the first plurality of leads, a first flat end surface of the base member of each lead in the first plurality of leads, and a second flat end surface of the base member of each lead in the first plurality of leads are plated with a wettable metal for soldering.

[0030] Optionally, further comprising a second plurality of leads extending away from the one or more die pads in a second direction opposite to the first direction, each lead in the second plurality of leads comprising:

[0031] A base member comprising:

[0032] a first side; and

[0033] a second side; and

[0034] a protruding member directly connected to the base member of the second plurality of leads, the protruding member of the second plurality of leads comprising: an end surface;

[0035] wherein the end face width of the protruding member of each lead in the second plurality of leads is less than 50% of the width of the base member of each lead in the second plurality of leads;

[0036] wherein more than 50% of the first side surface of the base member of each lead in the second plurality of leads and more than 50% of the second side surface of the base member of each lead in the second plurality of leads are plated with a wettable metal for soldering; and

[0037] The end surface of the protruding member of each lead in the second plurality of leads is not plated with a wettable metal for soldering.

[0038] Optionally, each lead in the second plurality of leads further comprises:

[0039] a first notch located between a first side surface of the base member of each lead in the second plurality of leads and an end surface of the protruding member of each lead in the second plurality of leads; and

[0040] a second notch located between the second side surface of the base member of each lead in the second plurality of leads and an end surface of the protruding member of each lead in the second plurality of leads; and

[0041] Wherein, a surface of the first notch of each lead in the second plurality of leads and a surface of the second notch of each lead in the second plurality of leads are both plated with a wettable metal for welding.

[0042] Optionally, the protruding member of each lead of the second plurality of leads further comprises:

[0043] a first planar side surface; and

[0044] a second flat side surface opposite the first flat side surface;

[0045] wherein the base member of each lead of the second plurality of leads further comprises:

[0046] a first planar end surface perpendicular to and directly connected to the first side surface of the base member of each of the second plurality of leads;

[0047] base and

[0048] a second planar end surface perpendicular to and directly connected to the second side surface of the base member of each lead of the second plurality of leads;

[0049] wherein the first flat side surface of the protruding member of each lead in the second group of leads, the second flat side surface of the protruding member of each lead in the second group of leads, the first flat end surface of the base member of each lead in the second group of leads, and the second flat end surface of the base member of each lead in the second group of leads are all plated with a wettable metal for welding.

[0050] Optionally, the lead frame further comprises:

[0051] a third plurality of leads extending away from the one or more die pads along a third direction perpendicular to the first direction, each lead in the third plurality of leads comprising:

[0052] A base member comprising:

[0053] a first side surface; and

[0054] a second side surface; and

[0055] a protruding member directly connected to the base member of the third plurality of leads, the protruding members of the third plurality of leads comprising:

[0056] an end face; and

[0057] a fourth plurality of leads extending away from the one or more die pads in a fourth direction opposite the third direction, each of the fourth plurality of leads comprising:

[0058] A base member comprising:

[0059] a first side; and

[0060] a second side; and

[0061] a protruding member directly connected to the base member of the fourth plurality of leads, the protruding members of the fourth plurality of leads comprising:

[0062] One end face;

[0063] wherein the width of the end surface of the protruding member of each lead of the third plurality of leads is less than 50% of the width of the base member of each lead of the third plurality of leads;

[0064] wherein more than 50% of the first side surface of the base member of each lead in the third plurality of leads and more than 50% of the second side surface of the base member of each lead in the third plurality of leads are plated with a wettable metal for soldering;

[0065] wherein an end surface of the protruding member of each lead of the third plurality of leads is not plated with a wettable metal for soldering;

[0066] wherein the width of the end surface of the protruding member of each lead in the fourth plurality of leads is less than 50% of the width of the base member in each lead in the fourth plurality of leads;

[0067] wherein more than 50% of the first side surface of the base member of each lead in the fourth plurality of leads and more than 50% of the second side surface of the base member of each lead in the fourth plurality of leads are plated with a wettable metal for soldering; and

[0068] The end surface of the protruding member of each lead in the fourth plurality of leads is not plated with a wettable metal for soldering.

[0069] The present invention also provides a method for manufacturing a semiconductor package, the method comprising the following steps: providing a lead frame array, the lead frame array comprising:

[0070] one or more lead frames, each of the one or more lead frames comprising one or more die pads;

[0071] A first barrier strip comprising:

[0072] a first plurality of barrier strip connecting portions;

[0073] A second barrier strip comprising:

[0074] a second plurality of barrier strip connecting portions;

[0075] a first plurality of grooves located between the first barrier rib and the first side of each lead frame;

[0076] a second plurality of grooves located between the second barrier rib and a second side of each lead frame, the second side of each lead frame being opposite to the first side of each lead frame;

[0077] a first plurality of leads extending in a first direction away from the one or more die pads, each of the first plurality of leads being connected to a first barrier rib; and

[0078] a second plurality of leads extending away from the one or more die paddles in a second direction opposite the first direction, each lead in the second plurality of leads being connected to a second barrier rib;

[0079] mounting a chip on one or more die pads;

[0080] forming a molded package to encapsulate the chip;

[0081] Applying a cutting process or a punching process to remove the first plurality of barrier rib connection portions and the second plurality of barrier rib connection portions;

[0082] Tin plating is performed on portions of the lead frame array not covered by the molded package; and a singulation process is applied.

[0083] Optionally, a wire bonding process or a clip bonding process is applied before the step of forming the molded package.

[0084] Optionally, each of the first plurality of barrier rib connecting portions and the second plurality of barrier rib connecting portions comprises:

[0085] a first end portion;

[0086] a central section; and

[0087] a second end opposite the first end;

[0088] wherein the cross-sectional area of the first end portion is smaller than the cross-sectional area of the central portion; and

[0089] The cross-sectional area of the second end portion is smaller than the cross-sectional area of the central portion.

[0090] Optionally, each of the first plurality of leads comprises:

[0091] a base member; and

[0092] a protruding member directly connected to the base member of the first plurality of leads;

[0093] wherein the width of the protruding member of each lead in the first plurality of leads is less than 50% of the width of the base member of each lead in the first plurality of leads;

[0094] Each of the second plurality of leads comprises:

[0095] a base member; and

[0096] a protruding member directly connected to the base member of the second plurality of leads; and

[0097] The width of the protruding member of each lead in the second plurality of leads is less than 50% of the width of the base member of each lead in the second plurality of leads.

[0098] Optionally, each of the first plurality of barrier strip connecting portions comprises:

[0099] a first arcuate portion; and

[0100] a second arcuate portion; and

[0101] Wherein, each of the second plurality of barrier strip connecting portions comprises:

[0102] a first arcuate portion; and

[0103] A second arcuate portion.

[0104] Optionally, each of the one or more lead frames further comprises:

[0105] a first plurality of rectangular holes positioned between the first plurality of barrier rib connection portions and the one or more die pads;

[0106] Wherein, a transverse dimension of each of the first plurality of rectangular holes is smaller than a transverse dimension of a corresponding barrier rib connecting portion of the first plurality of barrier rib connecting portions.

[0107] Optionally, each of the one or more lead frames further comprises:

[0108] A third barrier strip comprising:

[0109] a third plurality of barrier strip connecting portions;

[0110] a fourth barrier bar comprising:

[0111] a fourth group of a plurality of barrier strip connecting portions;

[0112] a third plurality of grooves located between the third barrier rib and the third side of each lead frame;

[0113] a fourth plurality of grooves located between the fourth barrier rib and a fourth side of each lead frame, the fourth side of each lead frame being opposite to the third side of each lead frame;

[0114] a third plurality of leads extending away from the one or more die pads along a third direction perpendicular to the first direction, each of the third plurality of leads being connected to a third barrier rib; and

[0115] a fourth plurality of leads extending away from the one or more die pads in a fourth direction opposite the third direction, each lead of the fourth plurality of leads being connected to a fourth barrier rib; and

[0116] The cutting process or the punching process is further used to remove the third group of barrier rib connection portions and the fourth group of barrier rib connection portions.

[0117] Optionally, each lead in the third plurality of leads comprises:

[0118] a base member; and

[0119] a protruding member directly connected to the base member of the third plurality of leads;

[0120] wherein the width of the protruding member of each of the third plurality of leads is less than 50% of the width of the base member of each of the third plurality of leads;

[0121] Each of the fourth plurality of leads comprises:

[0122] a base member; and

[0123] a protruding member directly connected to the base member of the fourth plurality of leads; and

[0124] The width of the protruding member of each lead in the fourth plurality of leads is less than 50% of the width of the base member of each lead in the fourth plurality of leads.

[0125] Optionally, each of the one or more lead frames further comprises:

[0126] a first plurality of holes, each hole being located between a pair of grooves in the first set of grooves; and

[0127] A second plurality of holes, each hole in the second plurality of holes is located between a corresponding pair of grooves in the second plurality of grooves.

[0128] In summary, compared with the prior art, the semiconductor package and the manufacturing method thereof provided by the present invention have the following beneficial effects:

[0129] A semiconductor package of the present invention includes a lead frame, a chip, and a molded package. The lead frame includes one or more die pads and a plurality of leads. Each of the plurality of leads includes a base member and a protruding member. The width of an end face of the protruding member of each of the plurality of leads is less than 50% of the width of the corresponding base member to improve solderability. BRIEF DESCRIPTION OF THE DRAWINGS

[0130] Figure 1 FIG2 shows a perspective view of a semiconductor package in an example of the present disclosure.

[0131] Figure 2A 1 shows a top view of leads in an example of the present disclosure.

[0132] Figure 2B FIG2 shows a top view of another lead in an example of the present disclosure.

[0133] Figure 3 is a top view of another semiconductor package in an example of the present disclosure.

[0134] Figure 4 is a flow chart of a process for developing a semiconductor package in an example of the present disclosure.

[0135] Figure 5A 、 5B 5C, 5D, 5E, 5F and 5G represent process steps for manufacturing a semiconductor package in an example of the present disclosure.

[0136] Figure 6 FIG. 2 shows a top view of another lead frame in an example of the present disclosure.

[0137] Figure 7 FIG. 2 shows a top view of a lead frame array in an example of the present disclosure. DETAILED DESCRIPTION

[0138] The following will be combined with the appended Figure 1 ~Attachment Figure 7 , the technical solutions, structural features, objectives achieved and effects in the embodiments of the present invention are described in detail.

[0139] It should be noted that the drawings are in a very simplified form and use non-precise proportions. They are only used to conveniently and clearly assist in explaining the embodiments of the present invention, and are not used to limit the conditions for the implementation of the present invention. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and purpose that can be achieved by the present invention.

[0140] It should be noted that, in the present invention, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only the elements explicitly listed, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0141] Figure 1 FIG shows a perspective view of a semiconductor package 100 in an example of the present disclosure. In one example, the semiconductor package 100 is a stamped dual flat leadless (DFN) package. The semiconductor package 100 includes Figure 5A Lead frame 510, Figure 5B The chip 550 and the molded package 190. The lead frame 510 includes Figure 5A The one or more die pads 512 and the first plurality of leads 120. The first plurality of leads 120 are spaced apart from each other along the first direction Y. Figure 5A One or more die pads 512 extend. Figure 1 124, 126, and 128 are shown, but the number of leads included in the first plurality of leads 120 can vary. Each of the first plurality of leads 120 includes a base member (or base portion) extending outside the molded package and a protruding member (or tip portion) extending to the end of each lead. For example, lead 122 includes a base member 132 and a protruding member 142. In one example, the thickness of base member 132 is equal to the thickness of protruding member 142. Protruding member 142 is directly connected to base member 132. Base member 132 includes a first side 133 and a second side 135. Protruding member 142 includes an end face 143. A portion 139 of the first side 133 of base member 132 adjacent to the molded package (representing the non-shaded area of copper exposed after the cutting process) is unplated. The end face 143 of protruding member 142 is located at the center portion of the end of lead 122 and is unplated. The hatched area 134 of the base member 132 and the hatched area 144 of the protruding member 142 are plated with a wettable metal for soldering. The hatched area 134 of the base member 132 is directly connected to the protruding member 142. In one example, the wettable metal for soldering covers the hatched area 134 of the base member 132 and the hatched area 144 of the protruding member 142. In one example, the wettable metal for soldering is tin or Sn.

[0142] Figure 5B The chip 550 is attached to Figure 5ALead frame 510 Figure 5A One or more die pads 512. The molded package 190 surrounds Figure 5B Chip 550.

[0143] Figure 2A The example in this disclosure shows Figure 1 A top view of the lead 122. The width 248 of the end surface 143 of the protruding member 142 of the lead 122 is less than 50% of the width 238 of the base member 132 of the lead 122 to reduce the non-plated surface area of the end region of the lead 122 (to improve solderability). In one example, the width 248 is 0.2 mm and the width 238 is in the range of 0.41 mm to 0.5 mm. More than 50% of the first side surface 133 of the base member 132 of the lead 122 is plated with a wettable metal for soldering. Figure 1 The length 274 of the hatched area 134 is longer than Figure 1 Length 279 of portion 139 (non-shaded area) is increased to increase the portion of the plated side surface of lead 122 (to improve solderability). Similarly, more than 50% of second side surface 135 of base member 132 of lead 122 is plated with a wettable metal for soldering.

[0144] In the example of the present disclosure, the lead 122 further includes a first notch 282 and a second notch 284 that form the protruding member 142 having a shape with a width that decreases away from the base member 132. The first notch 282 is located between the first side surface 133 of the base member 132 of the lead 122 and the end surface 143 of the protruding member 142 of the lead 122, thereby forming the protruding member 142 ( Figure 1 The second notch 284 is located between the second side 135 of the base member 132 of the lead 122 and the end face 143 of the protruding member 142 of the lead 122, thereby forming a second side 299 of the protruding member 142. The end face 143 separates the first side ( Figure 1 The first side (hatched area 144) of the protruding member 142 of the lead 122 is separated from the second side 299. Figure 1 The hatched area 144) and the second side 299 of the protruding member 142 are curved and plated with a wettable metal for soldering.

[0145] Figure 2BFIG2 shows a top view of a lead 250 in an example of the present disclosure. The lead 250 includes a base member 252 and a protruding member 262. In one example, the thickness of the base member 252 is equal to the thickness of the protruding member 262. The protruding member 262 is directly connected to the base member 252. The protruding member 262 of the lead 250 includes a first flat side surface 264 and a second flat side surface 266 opposite the first flat side surface 264. The base member 252 of the lead 250 includes a first flat end surface 254 and a second flat end surface 256. The first flat end surface 254 of the base member 252 is perpendicular to and directly connected to the first side 253 of the base member 252. The second flat end surface 256 of the base member 252 is perpendicular to and directly connected to the second side 255 of the base member 252. The first planar side surface 264 of the protruding member 262 , the second planar side surface 266 of the protruding member 262 , the first planar end surface 254 of the base member 252 , and the second planar end surface 256 of the base member 252 are plated with a wettable metal for soldering.

[0146] Figure 3 FIG is a top view of a semiconductor package 300 in an example of the present disclosure. In one example, the semiconductor package 300 is a stamped quad flat no-lead (QFN) package. The semiconductor package 300 includes Figure 6 The lead frame 610, the chip 301 and the molded package 399. The lead frame 610 includes Figure 5A The one or more die pads 512 and the first plurality of leads 320, the second plurality of leads 340, the third plurality of leads 360 and the fourth plurality of leads 380. The first plurality of leads 320 are spaced apart from each other along the first direction (positive Y direction). Figure 5A The second plurality of leads 340 extend away from the die pad 512 along a second direction (negative Y direction) opposite to the first direction (positive Y direction). Figure 5A The third plurality of leads 360 extend away from the first die pad 512 along a third direction (positive X direction) perpendicular to the first direction (positive Y direction). Figure 5A The fourth plurality of leads 380 extend away from the die pad 512 along a fourth direction (negative X direction) opposite to the third direction (positive X direction). Figure 5A One or more die pads 512 extend therefrom.

[0147] Each of the first plurality of leads 320 includes a base member and a protruding member. For example, lead 322 includes a base member 324 and a protruding member 334. Each of the second plurality of leads 340 includes a base member and a protruding member. For example, lead 342 includes a base member 344 and a protruding member 354. Each of the third plurality of leads 360 includes a base member and a protruding member. For example, lead 362 includes a base member 364 and a protruding member 374. Each of the fourth plurality of leads 380 includes a base member and a protruding member. For example, lead 382 includes a base member 384 and a protruding member 394.

[0148] Base member 324 includes a first side surface 327 and a second side surface. Protruding member 334 includes an end surface. The width 339 of the end surface of protruding member 334 is less than 50% of the width 329 of base member 324. Leads 342, 362, and 382 have similar structures. The width of the end surface of protruding member 354 is less than 50% of the width of base member 344. The width of the end surface of protruding member 374 is less than 50% of the width of base member 364. The width of the end surface of protruding member 394 is less than 50% of the width of base member 384.

[0149] More than 50% of the first side 327 of base member 324 and more than 50% of the second side of base member 324 are plated with a metal wettable for soldering. Leads 342, 362, and 382 have similar structures. More than 50% of the first side of base member 344 and less than 50% of the second side of base member 344 are plated with a metal wettable for soldering. More than 50% of the first side of base member 364 and more than 50% of the second side of base member 364 are plated with a metal wettable for soldering. More than 50% of both the first and second side surfaces of base member 384 are plated with a metal wettable for soldering.

[0150] The end surface of the protruding member 334 , the end surface of the protruding member 354 , the end surface of the protruding member 374 , and the end surface of the protruding member 394 are not plated with metal.

[0151] Figure 4 FIG. 4 is a flow chart of a process 400 for developing a semiconductor package according to an example of the present disclosure. The process 400 for developing a semiconductor package may begin at step 402 . Figures 5A-5G A top view of the corresponding steps is shown.

[0152] In step 402, now refer to Figure 5A , a lead frame array 500 is provided. The lead frame array 500 includes one or more lead frames, including lead frame 510. Although Figure 5AOnly four leadframes are shown, but the number of leadframes included in leadframe array 500 may vary. Leadframe 510 includes one or more die pads 512, a first barrier rib 514, a second barrier rib 524, a first plurality of grooves 519, a second plurality of grooves 529, a first plurality of leads 560, and a second plurality of leads 580. The first barrier rib 514 includes a first plurality of barrier rib connecting portions 515. The second barrier rib 524 includes a second plurality of barrier rib connecting portions 525. The first plurality of grooves 519 are located between the first barrier rib 514 and the first side 501 of the leadframe 510. The second plurality of grooves 529 are located between the second barrier rib 524 and the second side 503 of the leadframe 510.

[0153] A first plurality of leads 560 extend in a first direction (positive Y direction) away from the one or more die pads 512. Each of the first plurality of leads 560 is connected to a first barrier rib 514. A second plurality of leads 580 extend in a second direction (negative Y direction) away from the one or more die paddles 512. Each of the second plurality of leads 580 is connected to a second barrier rib 524.

[0154] In an example of the present disclosure, each of the first plurality of barrier rib connecting portions 515 includes a first end portion 515A, a central portion 515B, and a second end portion 515C. The central portion 515B is located between the first end portion 515A and the second end portion 515C. The cross-sectional area of the first end portion 515A is smaller than that of the central portion 515B. The cross-sectional area of the second end portion 515C is smaller than that of the central portion 515B.

[0155] In an example of the present disclosure, each of the first plurality of barrier rib connection portions includes a first arc portion and a second arc portion. For example, the barrier rib connection portion 513 includes a first arc portion 513A and a second arc portion 513B.

[0156] In an example of the present disclosure, each of the one or more lead frames further includes a first plurality of rectangular apertures positioned between the first plurality of barrier rib connecting portions and the one or more templates. For example, a plurality of rectangular apertures 592 are positioned between the first plurality of barrier rib connecting portions 515 and the one or more templates 512. Each of the first plurality of rectangular apertures has a lateral dimension that is smaller than a corresponding lateral dimension of a corresponding barrier rib connecting portion in the first plurality of barrier rib connecting portions. For example, dimension 562 is smaller than dimension 564. In one example, dimension 562 is 0.1 mm, and dimension 564 is in the range of 0.2 to 0.3 mm.

[0157] In an example of the present disclosure, the lead frame array 500 is not a pre-plated frame (PPF) array. Step 402 may be followed by step 404 .

[0158] In step 404, now refer to Figure 5B , chip 550 is mounted on one or more die pads 512. In one example, chip 550 is a power semiconductor transistor, such as a metal oxide semiconductor field effect transistor (MOSFET). Step 404 may be followed by step 406 or step 408.

[0159] In optional step 406 (shown in dashed box), reference is now made to Figure 5C , a wire bonding process and / or a clip bonding process is applied. One or more wires 552 connect the chip 550 to the gate lead 551, and a clip 556 connects the chip 550 to the source lead 553. Step 406 may be followed by step 408.

[0160] In step 408, now refer to Figure 5D , forming a molded package 598. The molded package 598 surrounds the chip 550. Step 408 may be followed by step 410.

[0161] In step 410, now refer to Figure 5E , using cutting process or stamping process. Figure 5A The first plurality of barrier rib connecting portions 515 are removed to form a first plurality of grooves 575 . Figure 5A The second plurality of barrier rib connecting portions 525 are removed to form a second plurality of grooves 585. The width 573 of the end surface of the protruding member of the lead 571 is less than 50% of the width 563 of the base member 572 of the lead 571 to reduce the non-plated surface area of the end region of the lead 571 (to improve solderability). Step 410 may be followed by step 412.

[0162] In step 412, now refer to Figure 5F , a plating process is applied. Portions of the lead frame 510 not covered by the molded package 598 are plated with a wettable metal for solder 599. In one example, step 412 is the only plating process in the process 400 of developing a semiconductor package (no other plating processes are performed). In one example, the wettable metal 599 for solder is tin or Sn. Step 412 may be followed by step 414.

[0163] In step 414, now refer to Figure 5G , a singulation process is applied (along the plurality of cutting lines 597 ) to form a plurality of semiconductor packages (e.g., Figure 1 semiconductor package 100).

[0164] The process 400 for developing semiconductor packages can also be applied to Figure 6The lead frame 610 includes one or more die paddles, a first barrier rib 620, a second barrier rib 630, a third barrier rib 640, a fourth barrier rib 650, a first plurality of grooves 622, a second plurality of grooves 632, a third plurality of grooves 642, a fourth plurality of grooves 652, a first plurality of leads 624, a second plurality of leads 634, a third plurality of leads 644, and a fourth plurality of leads 654.

[0165] Still refer to Figure 6 A first plurality of leads 624 extends away from one or more die lobes along a first direction (positive Y direction). Each of the first plurality of leads 624 is connected to a first barrier rib 620. A second plurality of leads 634 extends away from one or more die lobes along a second direction (negative Y direction). Each of the second plurality of leads 634 is connected to a second barrier rib 630. A third plurality of leads 644 extends away from one or more die lobes along a third direction (positive X direction). Each of the third plurality of leads 644 is connected to a third barrier rib 640. A fourth plurality of leads 654 extends away from one or more die lobes along a fourth direction (negative X direction). Each of the fourth plurality of leads 654 is connected to a fourth barrier rib 650.

[0166] Each of the first plurality of leads 624 includes a base member and a protruding member. For example, lead 628 includes a base member 627 and a protruding member 629. Each of the second plurality of leads 634 includes a base member and a protruding member. Each of the third plurality of leads 644 includes a base member and a protruding member. Each of the fourth plurality of leads 654 includes a base member and a protruding member.

[0167] The process 400 for developing semiconductor packages can also be applied to Figure 7Leadframe array 700 includes one or more leadframes, including leadframe 710. Leadframe 710 includes one or more die blades, a first barrier rib 720, a second barrier rib 730, a first plurality of grooves 722, a second plurality of grooves 732, a first plurality of holes 729, a second plurality of holes 739, a first plurality of leads 724 (extending in the positive Y direction), and a second plurality of leads 734 (extending in the negative Y direction). Each of the first plurality of holes 729 is located between a corresponding pair of grooves in the first plurality of grooves 722. Each of the second plurality of holes 739 is located between a corresponding pair of grooves in the second plurality of grooves 732. In one example, each of the first plurality of holes 729 and the second plurality of holes 739 is circular. In another example, each of the first plurality of holes 729 and the second plurality of holes 739 is shaped like a "+." After completing all steps of process 400 for developing a semiconductor package, the end surfaces at the lead tips 798 of the first plurality of leads 724 will be plated due to the first plurality of holes 729. The end surfaces at the lead tips 799 of the second plurality of leads 734 will be plated due to the second plurality of holes 739.

[0168] Those skilled in the art will recognize that modifications to the embodiments disclosed herein are possible. For example, the number of leads may be varied. Other modifications may be made by those skilled in the art, and all such modifications are considered to be within the scope of the present invention, as defined by the claims.

[0169] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description is not intended to limit the present invention. After reading the above description, various modifications and substitutions of the present invention will become apparent to those skilled in the art. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A semiconductor package, characterized in that: include: A lead frame comprising: one or more die pads; and A first plurality of leads extends from the one or more die pads along a first direction, each lead of the first plurality of leads comprising: A base member comprising: a first side; and a second side; and a protruding member directly connected to the base member of the first plurality of leads, the protruding member of the first plurality of leads comprising: One end face; a chip attached to one or more die pads on a lead frame; and a molded package encapsulating the chip; wherein the end face width of the protruding member of each lead of the first plurality of leads is less than 50% of the width of the base member of each lead of the first plurality of leads; and The end surface of the protruding member of each lead in the first plurality of leads is not plated with a wettable metal for soldering.

2. The semiconductor package according to claim 1, wherein More than 50% of the first side surface of the base member of each of the first plurality of leads and more than 50% of the second side surface of the base member of each of the first plurality of leads are plated with a wettable metal for soldering.

3. The semiconductor package according to claim 1, wherein Each lead in the first plurality of leads further comprises: a first notch located between a first side surface of the base member of each of the first plurality of leads and an end surface of the protruding member of each of the first plurality of leads; and a second notch located between the second side surface of the base member of each of the first plurality of leads and an end surface of the protruding member of each of the first plurality of leads; and Wherein, a surface of the first notch of each lead in the first plurality of leads and a surface of the second notch of each lead in the first plurality of leads are plated with a wettable metal for welding.

4. The semiconductor package according to claim 1, wherein The protruding member of each lead of the first plurality of leads further comprises: a first planar side surface; and a second flat side surface opposite to the first flat side surface; wherein the base member of each lead of the first plurality of leads further comprises: a first planar end surface perpendicular to and directly connected to the first side surface of the base member of each of the first plurality of leads; and a second planar end surface perpendicular to and directly connected to the second side surface of the base member of each of the first plurality of leads; wherein a first flat side surface of the protruding member of each lead in the first plurality of leads, a second flat side surface of the protruding member of each lead in the first plurality of leads, a first flat end surface of the base member of each lead in the first plurality of leads, and a second flat end surface of the base member of each lead in the first plurality of leads are plated with a wettable metal for soldering.

5. The semiconductor package according to claim 1, wherein Also included is a second plurality of leads extending away from the one or more die pads in a second direction opposite the first direction, each lead of the second plurality of leads comprising: A base member comprising: a first side; and a second side; and a protruding member directly connected to the base member of the second plurality of leads, the protruding member of the second plurality of leads comprising: an end surface; wherein the end face width of the protruding member of each lead in the second plurality of leads is less than 50% of the width of the base member of each lead in the second plurality of leads; wherein more than 50% of the first side surface of the base member of each lead in the second plurality of leads and more than 50% of the second side surface of the base member of each lead in the second plurality of leads are plated with a wettable metal for soldering; and The end surface of the protruding member of each lead in the second plurality of leads is not plated with a wettable metal for soldering.

6. The semiconductor package according to claim 5, wherein Each lead of the second plurality of leads further comprises: a first notch located between a first side surface of the base member of each lead in the second plurality of leads and an end surface of the protruding member of each lead in the second plurality of leads; and a second notch located between the second side surface of the base member of each lead in the second plurality of leads and an end surface of the protruding member of each lead in the second plurality of leads; and Wherein, a surface of the first notch of each lead in the second plurality of leads and a surface of the second notch of each lead in the second plurality of leads are both plated with a wettable metal for welding.

7. The semiconductor package according to claim 5, wherein The protruding member of each lead of the second plurality of leads further comprises: a first planar side surface; and a second flat side surface opposite the first flat side surface; wherein the base member of each lead of the second plurality of leads further comprises: a first planar end surface perpendicular to and directly connected to the first side surface of the base member of each of the second plurality of leads; base and a second planar end surface perpendicular to and directly connected to the second side surface of the base member of each lead of the second plurality of leads; wherein the first flat side surface of the protruding member of each lead in the second group of leads, the second flat side surface of the protruding member of each lead in the second group of leads, the first flat end surface of the base member of each lead in the second group of leads, and the second flat end surface of the base member of each lead in the second group of leads are all plated with a wettable metal for welding.

8. The semiconductor package according to claim 5, wherein The lead frame also includes: a third plurality of leads extending away from the one or more die pads along a third direction perpendicular to the first direction, each lead in the third plurality of leads comprising: A base member comprising: a first side surface; and a second side surface; and a protruding member directly connected to the base member of the third plurality of leads, the protruding members of the third plurality of leads comprising: an end face; and a fourth plurality of leads extending away from the one or more die pads in a fourth direction opposite the third direction, each of the fourth plurality of leads comprising: A base member comprising: a first side; and a second side; and a protruding member directly connected to the base member of the fourth plurality of leads, the protruding members of the fourth plurality of leads comprising: One end face; wherein the width of the end surface of the protruding member of each lead of the third plurality of leads is less than 50% of the width of the base member of each lead of the third plurality of leads; wherein more than 50% of the first side surface of the base member of each lead in the third plurality of leads and more than 50% of the second side surface of the base member of each lead in the third plurality of leads are plated with a wettable metal for soldering; wherein an end surface of the protruding member of each lead of the third plurality of leads is not plated with a wettable metal for soldering; wherein the width of the end surface of the protruding member of each lead in the fourth plurality of leads is less than 50% of the width of the base member in each lead in the fourth plurality of leads; wherein more than 50% of the first side surface of the base member of each lead in the fourth plurality of leads and more than 50% of the second side surface of the base member of each lead in the fourth plurality of leads are plated with a wettable metal for soldering; and The end surface of the protruding member of each lead in the fourth plurality of leads is not plated with a wettable metal for soldering.

9. A method for manufacturing a semiconductor package, characterized in that The method comprises the following steps: A lead frame array is provided, the lead frame array comprising: one or more lead frames, each of the one or more lead frames comprising one or more die pads; A first barrier strip comprising: a first plurality of barrier strip connecting portions; A second barrier strip comprising: a second plurality of barrier strip connecting portions; a first plurality of grooves located between the first barrier rib and the first side of each lead frame; a second plurality of grooves located between the second barrier rib and a second side of each lead frame, the second side of each lead frame being opposite to the first side of each lead frame; a first plurality of leads extending in a first direction away from the one or more die pads, each of the first plurality of leads being connected to a first barrier rib; and a second plurality of leads extending away from the one or more die paddles in a second direction opposite the first direction, each lead in the second plurality of leads being connected to a second barrier rib; mounting a chip on one or more die pads; forming a molded package to encapsulate the chip; Applying a cutting process or a punching process to remove the first plurality of barrier rib connection portions and the second plurality of barrier rib connection portions; Tin plating is performed on portions of the lead frame array not covered by the molded package; and a singulation process is applied.

10. The method according to claim 9, characterized in that A wire bonding process or a clip bonding process is applied before the step of forming the molded package.

11. The method according to claim 9, wherein Each of the first plurality of barrier rib connecting portions and the second plurality of barrier rib connecting portions comprises: a first end portion; a central section; and a second end opposite the first end; wherein the cross-sectional area of the first end portion is smaller than the cross-sectional area of the central portion; and The cross-sectional area of the second end portion is smaller than the cross-sectional area of the central portion.

12. The method according to claim 9, characterized in that Each of the first plurality of leads comprises: a base member; and a protruding member directly connected to the base member of the first plurality of leads; wherein the width of the protruding member of each lead in the first plurality of leads is less than 50% of the width of the base member of each lead in the first plurality of leads; Each of the second plurality of leads comprises: a base member; and a protruding member directly connected to the base member of the second plurality of leads; and The width of the protruding member of each lead in the second plurality of leads is less than 50% of the width of the base member of each lead in the second plurality of leads.

13. The method according to claim 9, characterized in that Each of the first plurality of barrier rib connecting portions comprises: a first arcuate portion; and a second arcuate portion; and Wherein, each of the second plurality of barrier strip connecting portions comprises: a first arcuate portion; and A second arcuate portion.

14. The method according to claim 9, wherein Each of the one or more lead frames further comprises: a first plurality of rectangular holes positioned between the first plurality of barrier rib connection portions and the one or more die pads; Wherein, a transverse dimension of each of the first plurality of rectangular holes is smaller than a transverse dimension of a corresponding barrier rib connecting portion of the first plurality of barrier rib connecting portions.

15. The method according to claim 9, characterized in that Each of the one or more lead frames further comprises: A third barrier strip comprising: a third plurality of barrier strip connecting portions; a fourth barrier bar comprising: a fourth group of a plurality of barrier strip connecting portions; a third plurality of grooves located between the third barrier rib and the third side of each lead frame; a fourth plurality of grooves located between the fourth barrier rib and a fourth side of each lead frame, the fourth side of each lead frame being opposite to the third side of each lead frame; a third plurality of leads extending away from the one or more die pads along a third direction perpendicular to the first direction, each of the third plurality of leads being connected to a third barrier rib; and a fourth plurality of leads extending away from the one or more die pads in a fourth direction opposite the third direction, each lead of the fourth plurality of leads being connected to a fourth barrier rib; and The cutting process or the punching process is used to further remove the third group of multiple barrier rib connection portions and the fourth group of multiple barrier rib connection portions.

16. The method according to claim 15, characterized in that Each lead of the third plurality of leads comprises: a base member; and a protruding member directly connected to the base member of the third plurality of leads; wherein the width of the protruding member of each of the third plurality of leads is less than 50% of the width of the base member of each of the third plurality of leads; Each of the fourth plurality of leads comprises: a base member; and a protruding member directly connected to the base member of the fourth plurality of leads; and The width of the protruding member of each lead in the fourth plurality of leads is less than 50% of the width of the base member of each lead in the fourth plurality of leads.

17. The method according to claim 9, characterized in that Each of the one or more lead frames further comprises: a first plurality of holes, each hole being located between a pair of grooves in the first set of grooves; and A second plurality of holes, each hole in the second plurality of holes is located between a corresponding pair of grooves in the second plurality of grooves.

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