Lead frame and method for manufacturing the same

Abstract

To provide a lead frame and a method for manufacturing the same that can easily form deep recesses.SOLUTION: A lead frame includes an annular frame portion having a first support portion and a plurality of lead portions extending from the first support portion to the inside of the frame portion, the frame portion and the lead portions have a first surface and a second surface opposite to the first surface, a plurality of first recesses are formed on the first surface of the first support portion and a second recess is formed on the second surface of each of the lead portions.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] TECHNICAL FIELD The present disclosure relates to leadframes and methods of manufacturing leadframes. [Background technology]

[0002] Lead frames are used in the manufacture of semiconductor devices such as QFN (quad flat non-leaded package). A structure called wettable flank is known in QFN, in which a recess is formed in the lead to improve the wettability of the solder. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-061266 [Patent Document 2] JP 2021-125611 A Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional lead frames used with wettable flanks, it is not easy to form deep recesses due to their structure.

[0005] An object of the present disclosure is to provide a lead frame that allows deep recesses to be easily formed, and a method for manufacturing the lead frame. [Means for solving the problem]

[0006] According to one embodiment of the present disclosure, there is provided a lead frame having an annular frame portion having a first support portion and a plurality of lead portions extending from the first support portion to an inside of the frame portion, the frame portion and the lead portions having a first surface and a second surface opposite the first surface, a plurality of first recesses formed on the first surface of the first support portion, and a second recess formed on the second surface of each of the lead portions. Effect of the Invention

[0007] According to the disclosed technique, a deep recess can be easily formed. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a diagram illustrating an overview of a lead frame according to the first embodiment. [Diagram 2] FIG. 2 is a top view illustrating the lead frame according to the first embodiment. [Diagram 3] FIG. 2 is a bottom view illustrating the lead frame according to the first embodiment. [Figure 4] 1 is a cross-sectional view illustrating a lead frame according to a first embodiment. [Diagram 5] 1A to 1C are cross-sectional views (part 1) illustrating the method for manufacturing the lead frame according to the first embodiment. [Figure 6] 5A to 5C are cross-sectional views (part 2) illustrating the method for manufacturing the lead frame according to the first embodiment. [Figure 7] 5A to 5C are cross-sectional views (part 3) illustrating the method for manufacturing the lead frame according to the first embodiment. [Figure 8] 4 is a cross-sectional view (part 4) showing the method for manufacturing the lead frame according to the first embodiment; FIG. [Figure 9] 1A to 1C are cross-sectional views (part 1) illustrating a method for manufacturing a semiconductor device using a lead frame according to a first embodiment. [Figure 10] 5A to 5C are cross-sectional views (part 2) illustrating the method for manufacturing a semiconductor device using the lead frame according to the first embodiment. [Figure 11] 1A to 1C are cross-sectional views illustrating examples of usage of a semiconductor device. [Figure 12] FIG. 11 is a top view illustrating a lead frame according to a second embodiment. [Figure 13] 13 is a bottom view illustrating the lead frame according to the second embodiment. FIG. [Figure 14] FIG. 13 is a top view illustrating a lead frame according to a third embodiment. [Figure 15] 13 is a bottom view illustrating the lead frame according to the fourth embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functional configuration may be denoted by the same reference numerals to avoid redundant description. In the following description, an XYZ orthogonal coordinate system is used, and the +Z side may be referred to as the upper side, upper side, or top, and the -Z side may be referred to as the lower side, lower side, or bottom, as viewed from any point. The lower surface may be referred to as one surface or lower surface, and the upper surface may be referred to as the other surface or upper surface. However, this coordinate system is defined for the purpose of explanation and does not limit the position of the lead frame. The lead frame can be used upside down or placed at any angle. In addition, a planar view refers to a view of an object from the normal direction of one surface of the lead frame, and a planar shape refers to a shape of an object viewed from the normal direction of one surface of the lead frame. In this disclosure, a flat surface is a surface that is not intentionally curved or has no irregularities. The arithmetic mean roughness Ra of the flat surface is 0.125 μm or less.

[0010] (First embodiment) First, a first embodiment will be described. The first embodiment relates to a lead frame. The lead frame according to the first embodiment is a lead frame on which a semiconductor element is mounted and which is covered with a sealing resin to become a semiconductor device.

[0011] [Lead frame structure] The structure of the lead frame according to the first embodiment will be described. FIG. 1 is a diagram illustrating an outline of the lead frame according to the first embodiment. FIG. 2 is a top view illustrating the lead frame according to the first embodiment. FIG. 3 is a bottom view illustrating the lead frame according to the first embodiment. FIG. 4 is a cross-sectional view illustrating the lead frame according to the first embodiment. FIGS. 2 and 3 show an enlarged view of a portion of FIG. 1. FIG. 4(a) corresponds to a cross-sectional view taken along line IVa-IVa in FIGS. 1 and 2. FIG. 4(b) corresponds to a cross-sectional view taken along line IVb-IVb in FIGS. 1 and 2.

[0012] As shown in Fig. 1, the lead frame 1 according to the first embodiment has a plurality of singulation regions 30. For example, the singulation regions 30 have a rectangular planar shape. Between the singulation regions 30 are cut regions 40 that are cut during singulation. Figs. 2 to 4 mainly show two singulation regions 30 adjacent to each other along the X-axis direction and the cut regions 40 around them.

[0013] The lead frame 1 has a frame portion 100 in the cutting region 40. The frame portion 100 has a plurality of first support portions 110 extending in the Y-axis direction and a plurality of second support portions 120 extending in the X-axis direction. Each of the first support portions 110 intersects with the plurality of second support portions 120, and each of the second support portions 120 intersects with the plurality of first support portions 110. The frame portion 100 has an annular planar shape composed of two adjacent first support portions 110 and two adjacent second support portions 120.

[0014] The lead frame 1 has, in each singulation region 30, a plurality of lead portions 200 extending from the first support portion 110 to the inside of the annular frame portion 100, a die pad portion 300 provided on the inside of the annular frame portion 100, and a connecting portion 400 connecting the second support portion 120 and the die pad portion 300. The plurality of lead portions 200 are aligned in the Y-axis direction for each first support portion 110.

[0015] The frame portion 100, the lead portion 200, the die pad portion 300 and the connecting portion 400 have a first surface 10 (upper surface) on one side and a second surface 20 (lower surface) on the other side opposite to the first surface 10. The first surface 10 is shown in Fig. 2, and the second surface 20 is shown in Fig. 3.

[0016] The material of the lead frame 1 may be, for example, copper (Cu), a Cu alloy, an alloy 42, etc. The thickness of the lead frame 1 may be, for example, about 100 μm to 300 μm.

[0017] In the following, attention will be mainly focused on one singulation region 30, and the two first support portions 110 and two second support portions 120 adjacent to this singulation region 30 will be considered as one frame portion 100 for explanation.

[0018] 2 and 4, each of the lead portions 200 has a flat surface 201 on the first surface 10. The flat surface 201 is parallel to the XY plane. For example, the entire first surface 10 of the lead portion 200 is the flat surface 201. The flat surface 201 is connected to the first support portion 110.

[0019] As shown in Figs. 3 and 4, each of the lead portions 200 has a flat surface 202 and a recess 209 on the second surface 20. The flat surface 202 is parallel to the flat surface 201. The recess 209 is recessed from the flat surface 202 toward the flat surface 201. There are parts of the flat surface 202 on both the +Y side and the -Y side of the recess 209. For example, in a semiconductor device having a wettable flank structure, the flat surface 202 becomes the mounting surface of the lead, and the recess 209 becomes the recess of the lead. The flat surface 202 and the recess 209 are connected to the first support 110. Each of the lead portions 200 is supported by the first support 110. The first support 110 is sometimes called a sawing bar.

[0020] The depth of recess 209 is about 70% of the distance between flat surface 201 and flat surface 202. Flat surface 201 is an example of a fourth flat surface, flat surface 202 is an example of a second flat surface, and recess 209 is an example of a second recess.

[0021] As shown in FIG. 2 and FIG. 4, the first support 110 has a plurality of recesses 119 and a plurality of flat surfaces 111 on the first surface 10. The flat surface 111 is parallel to the XY plane and is continuous with the flat surface 201 of the lead portion 200. The flat surface 111 and the flat surface 201 are flush with each other. The plurality of flat surfaces 111 are aligned in the Y-axis direction. The recess 119 is between the two flat surfaces 111 aligned in the Y-axis direction. The recess 119 is also between the second support 120 and the flat surface 111 closest to the second support 120. From another perspective, the flat surface 111 is between the adjacent recesses 119.

[0022] As shown in Figures 3 and 4, the first support portion 110 has a plurality of recesses 118 and a plurality of flat surfaces 112 on the second surface 20. The flat surfaces 112 are parallel to the flat surface 111 and are continuous with the flat surface 202 of the lead portion 200. The flat surfaces 112 and 202 are flush with each other. The plurality of flat surfaces 112 are aligned in the Y-axis direction. The recesses 118 are continuous with the recesses 209 of the lead portion 200 and are located between the two flat surfaces 112 aligned in the Y-axis direction.

[0023] Recess 119 is shallower than recess 209. The depth of recess 119 is about 50% of the distance between flat surface 201 and flat surface 202, and the depth of recess 118 is about 70% of the distance between flat surface 201 and flat surface 202. Recess 119 is an example of a first recess, flat surface 111 is an example of a third flat surface, and flat surface 112 is an example of a first flat surface.

[0024] 2, the second support part 120 has a flat surface 121 on the first surface 10. The flat surface 121 is parallel to the XY plane and is flush with the flat surfaces 111 and 201. For example, the entire first surface 10 of the second support part 120 is the flat surface 121.

[0025] 3, the second support portion 120 has a recess 128 on the second surface 20. The recess 128 is located between two adjacent first support portions 110. The depth of the recess 128 is about 70% of the distance between the flat surface 201 and the flat surface 202. The second support portion 120 in the first embodiment is sometimes called a connecting bar.

[0026] 2 and 4, the die pad portion 300 has a flat surface 301 on the first surface 10. The flat surface 301 is parallel to the XY plane and is flush with the flat surfaces 111 and 201. A semiconductor element is mounted on the flat surface 301. The flat surface 301 is an example of a fifth flat surface.

[0027] 3 and 4, the die pad portion 300 has a flat surface 302 on the second surface 20. The flat surface 302 is parallel to the flat surface 301 and is flush with the flat surface 112 and the flat surface 202. The die pad portion 300 may have a recess surrounding the flat surface 302 on the second surface 20. The flat surface 302 is an example of a sixth flat surface.

[0028] 2, the connecting part 400 has a flat surface on the first surface 10 that is parallel to the XY plane and continues to the flat surface 121 and the flat surface 301. The flat surface of the first surface 10 of the connecting part 400 is flush with the flat surface 121 and the flat surface 301. As shown in FIG. 3, the connecting part 400 has a recess on the second surface 20 that continues to the recess 128 and the recess of the die pad part 300. The depth of the recess of the connecting part 400 is about 70% of the distance between the flat surface 201 and the flat surface 202.

[0029] [Lead frame manufacturing method] Next, a method for manufacturing the lead frame 1 according to the first embodiment will be described. Figures 5 to 8 are cross-sectional views illustrating the method for manufacturing the lead frame according to the first embodiment. Figures 5(a) to 8(a) show changes in a portion obtained by rotating the cross section shown in Figure 4(a) 180 degrees around the Y axis, and Figures 5(b) to 8(b) show changes in a portion obtained by rotating the cross section shown in Figure 4(b) 180 degrees around the Y axis.

[0030] First, as shown in Fig. 5(a) and (b), a metal plate 1A made of metal and having a predetermined shape is prepared. The metal plate 1A is a member to be cut at the cutting region 40 and diced into individual pieces for each individualization region 30. For example, copper, copper alloy, 42 alloy, etc. can be used as the material of the metal plate 1A. The thickness of the metal plate 1A can be, for example, about 100 µm to 300 µm. The metal plate 1A has a first surface 10A on one side and a second surface 20A on the other side opposite to the first surface 10A.

[0031] Next, a photosensitive resist 510 is formed on the first surface 10A of the metal plate 1A, and a photosensitive resist 520 is formed on the second surface 20A of the metal plate 1A. The resists 510 and 520 may be formed, for example, by applying and drying a resist liquid, or by attaching a resist film. As the resists 510 and 520, for example, a dry film resist such as an epoxy resin or an acrylic resin, an electrodeposition resist, or the like may be used.

[0032] Next, as shown in FIGS. 6(a) and 6(b), the resist 510 is exposed and developed to form a coating pattern 511 and an opening 512 in the resist 510, and the resist 520 is exposed and developed to form a coating pattern 521 and an opening 522 in the resist 520. The coating pattern 511 covers a portion of the first surface 10A where a flat surface included in the first surface 10 of the lead frame 1 is to be formed. The opening 512 is a portion for forming an opening or a recess in the metal plate 1A, and the remaining portion of the first surface 10A is exposed from the opening 512. The coating pattern 521 covers a portion of the second surface 20A where a flat surface included in the second surface 20 of the lead frame 1 is to be formed. The opening 522 is a portion for forming an opening or a recess in the metal plate 1A, and the remaining portion of the second surface 20A is exposed from the opening 522.

[0033] Next, as shown in Fig. 7(a) and (b), half etching of the metal plate 1A is performed from the 10A side and the second surface 20A side of the metal plate 1A using the resists 510 and 520 as etching masks. In this half etching, wet etching is performed in which the first surface 10A faces downward in the vertical direction and the second surface 20A faces upward in the vertical direction, and an etching solution is supplied to the first surface 10A and the second surface 20A. For example, spray etching is performed in which an etching solution is sprayed toward the first surface 10A and the second surface 20A. When the metal plate 1A is copper, for example, an aqueous solution of ferric chloride or cupric chloride can be used as the etching solution in the half etching of the metal plate 1A.

[0034] By orienting the first surface 10A vertically downward and the second surface 20A vertically upward, the etching liquid is likely to remain on the second surface 20A and is likely to fall from the first surface 10A. Therefore, the etching rate on the second surface 20A is higher than the etching rate on the first surface 10A. For example, when etching of the first surface 10A from the vertically downward side has progressed by about 50% of the thickness of the metal plate 1A, etching of the second surface 20A from the vertically upward side has progressed by about 70% of the thickness of the metal plate 1A.

[0035] By such half etching, a recess 119 of the first support portion 110 is formed on the first surface 10A, and a recess 209 of the lead portion 200, a recess 118 of the first support portion 110, a recess 128 of the second support portion 120, and recesses of the die pad portion 300 and the connecting portion 400 are formed on the second surface 20A.

[0036] 8(a) and 8(b), the resists 510 and 520 are removed. The resists 510 and 520 can be removed, for example, with a remover. Thereafter, if necessary, a plating layer such as silver plating may be formed by electrolytic plating on the connection portion of the bonding wire of the lead portion 200.

[0037] In this manner, the lead frame 1 can be manufactured.

[0038] [Method of manufacturing semiconductor device] Next, a method for manufacturing a semiconductor device using the lead frame 1 according to the first embodiment will be described. Figs. 9 and 10 are cross-sectional views illustrating the method for manufacturing a semiconductor device using the lead frame 1 according to the first embodiment. Figs. 9 and 10 correspond to cross-sectional views taken along line IVa-IVa in Fig. 2. Although multiple semiconductor devices can be manufactured using the lead frame 1, Figs. 9 and 10 mainly show the process for manufacturing one semiconductor device.

[0039] 9(a), a lead frame 1 is prepared, and a semiconductor element 71 is mounted on the first surface 10 of the die pad portion 300 in each singulation region 30. At this time, the first surface 10 of the die pad portion 300 and the back surface of the semiconductor element 71 on which no electrodes are formed are joined by an adhesive (not shown). As the adhesive, a die attach film, silver paste, solder, or the like is used.

[0040] 9(b), the first surface 10 of the lead portion 200 and an electrode provided on the surface of the semiconductor element are electrically connected using a bonding wire 72. A plating layer may be provided on the portion of the first surface 10 of the lead portion 200 to which the bonding wire 72 is connected.

[0041] 9(c), the semiconductor element 71 and the bonding wires 72 are sealed with a sealing resin 73. At this time, the semiconductor element 71 and the bonding wires 72 are sealed with a single sealing resin 73 that is common to the plurality of individualized regions 30. The upper and side surfaces of the lead frame 1 are also sealed with the sealing resin 73. As the sealing resin 73, for example, a so-called mold resin in which a filler is contained in an epoxy resin can be used. The sealing resin 73 can be formed by, for example, a transfer molding method or a compression molding method.

[0042] 10(a), a plating layer 74 is formed by electrolytic plating on the second surface 20 of the lead frame 1. The plating layer 74 is a solder layer containing one or more of, for example, tin (Sn), lead (Pb), silver (Ag), etc.

[0043] Next, as shown in FIG. 10(b), the cutting region 40 is cut using a cutting blade to separate the individual regions 30. As a result, the frame 100 is removed, and the semiconductor device 5 is obtained. When cutting the cutting region 40, the frame 100 can be easily removed because the recess 119 is formed in the first support 110 and the recess 128 is formed in the second support 120. That is, since the thickness of the frame 100 is thinner than when the recesses 119 and 128 are not formed, the frame 100 can be removed while reducing wear of the cutting blade and suppressing the generation of burrs. The semiconductor device 5 has a plurality of lead portions 200, and the lead portions 200 are formed with recesses 209 having a depth of about 70% of the distance between the flat surface 201 and the flat surface 202.

[0044] The semiconductor device 5 is mounted on, for example, a printed wiring board when used. Fig. 11 is a cross-sectional view illustrating an example of a use form of the semiconductor device 5. As shown in Fig. 11, the semiconductor device 5 is mounted on a printed wiring board 81. When the semiconductor device 5 is manufactured, a lead portion 200 is joined to a wiring 83 provided on the printed wiring board 81 by a solder material 82. The solder material 82 contains one or more kinds of elements such as Sn, Pb, Ag, etc.

[0045] In the lead frame 1, since the recess 209 is formed in the lead portion 200, a large contact area can be secured between the solder material 82 and the plating layer 74 provided on the lead portion 200. In addition, a fillet can be formed in the solder material 82, and the bonding state between the printed wiring board 81 and the semiconductor device 5 can be easily confirmed. In addition, the bonding strength between the printed wiring board 81 and the semiconductor device 5 can be improved.

[0046] In the lead frame 1 according to this embodiment, the recess 209 is formed on the second surface 20 of the lead portion 200, and the recess 119 is formed on the first surface 10 of the first support portion 110, so that the depths of the recesses 209 and 119 can be made different. For example, the recess 209 can be formed deep to ensure high wettability, while the recess 119 can be formed shallower than the recess 209 to ensure the strength of the first support portion 110. In addition, the recesses 209 and 119 can be formed by a single half etching. If the recess 119 is formed on the second surface 20 of the first support portion 110, the depths of the recesses 209 and 119 cannot be made different by a single half etching. For this reason, if the recess 209 is formed deep to ensure high wettability, the recess 119 also becomes deep, and there is a risk that the first support portion 110 will be easily deformed.

[0047] The mounting of the semiconductor element on the lead frame is not limited to connection by bonding wires. For example, flip chip connection may be used in which the electrodes of the semiconductor element are connected to the leads by solder bumps. In this case, the die pad may be omitted from the lead frame.

[0048] Second embodiment Next, a second embodiment will be described. The second embodiment differs from the first embodiment mainly in the configuration of the second support part. Fig. 12 is a top view illustrating a lead frame according to the second embodiment. Fig. 13 is a bottom view illustrating a lead frame according to the second embodiment. Figs. 12 and 13 mainly show two adjacent singulation regions 30 along the X-axis direction and the cutting region 40 around them.

[0049] 12 and 13, the lead frame 2 according to the second embodiment differs from the first embodiment in the configuration of the second support portion 120. The second support portion 120 in the second embodiment is sometimes called a sawing bar.

[0050] 12, the second support portion 120 has a recess 129 on the first surface 10. The recess 129 is located between two adjacent first support portions 110 and is connected to the recess 119 of the first support portion 110. The recess 129 is shallower than the recess 209. The depth of the recess 129 is about 50% of the distance between the flat surface 201 and the flat surface 202. The recess 129 is an example of a third recess.

[0051] 13, the second support part 120 has a flat surface 122 on the second surface 20. The flat surface 122 is parallel to the XY plane and is continuous with the flat surface 112 of the first support part 110. The flat surface 122 is flush with the flat surface 112 and the flat surface 202. For example, the entire second surface 20 of the second support part 120 is the flat surface 122.

[0052] Other configurations of the second embodiment are similar to those of the first embodiment. The second embodiment can also provide the same effects as the first embodiment. In addition, since the recess 129 is formed on the first surface 10, the depth of the recess 129 can be made different from the depth of the recess 209 of the lead portion 200, and can be made approximately the same as the depth of the recess 119, for example. Therefore, the strength of the second support portion 120 can be increased compared to the first embodiment, and the second support portion 120 can be made less likely to deform.

[0053] Third embodiment Next, a third embodiment will be described. The third embodiment differs from the second embodiment mainly in that it includes a lead portion supported by a second support portion. Fig. 14 is a top view illustrating a lead frame according to the third embodiment. Fig. 15 is a bottom view illustrating a lead frame according to the third embodiment. Figs. 14 and 15 mainly show one singulation region 30 and the cutting region 40 around it.

[0054] As shown in FIGS. 14 and 15, the lead frame 3 according to the third embodiment has a lead portion 600 supported by a second support portion 120 in addition to the lead portion 200 supported by the first support portion 110. As shown in FIG.

[0055] 14 , each of the lead portions 600 has a flat surface 601 on the first surface 10. The flat surface 601 is parallel to the XY plane and is flush with the flat surface 201 of the lead portion 200. For example, the entire first surface 10 of the lead portion 600 is the flat surface 601. The flat surface 601 is connected to the second support portion 120.

[0056] As shown in FIG. 15, each of the lead portions 600 has a flat surface 602 and a recess 609 on the second surface 20. The flat surface 602 is parallel to the flat surface 601 and is flush with the flat surface 202 of the lead portion 200. The recess 609 is recessed from the flat surface 602 toward the flat surface 601. There are parts of the flat surface 602 on both the +X side and the -X side of the recess 609. For example, in a semiconductor device having a wettable flank structure, the flat surface 602 becomes the mounting surface of the lead, and the recess 609 becomes the recess of the lead. The flat surface 602 and the recess 609 are connected to the second support portion 120. Each of the lead portions 600 is supported by the second support portion 120. The depth of the recess 609 is about 70% of the distance between the flat surface 601 and the flat surface 602, that is, the distance between the flat surface 201 and the flat surface 202.

[0057] As shown in FIG. 14, the second support 120 has a plurality of flat surfaces 126 in addition to the recess 129 on the first surface 10. The flat surfaces 126 are parallel to the XY plane and are continuous with the flat surface 601 of the lead portion 600. The flat surfaces 126 and the flat surfaces 601 are flush with each other. The plurality of flat surfaces 126 are aligned in the X-axis direction. The recess 129 is between the two flat surfaces 126 aligned in the X-axis direction. The recess 129 is also between the first support 110 and the flat surface 126 closest to the first support 110. From another perspective, the flat surfaces 126 are between the adjacent recesses 129.

[0058] 15, the second support portion 120 has a plurality of recesses 127 on the second surface 20 in addition to the flat surface 122. The recesses 127 are connected to the recesses 609 of the lead portion 600 and are located between the two flat surfaces 122 aligned in the X-axis direction. The depth of the recesses 127 is about 70% of the distance between the flat surface 201 and the flat surface 202.

[0059] Other configurations of the third embodiment are similar to those of the second embodiment. The third embodiment can also provide the same effects as the second embodiment.

[0060] Although the preferred embodiments have been described in detail above, the present disclosure is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims. [Explanation of symbols]

[0061] 1, 2, 3 Leadframe 1A metal plate 10, 10A 1st side 20, 20A 2nd page 71 Semiconductor Devices 82 Soldering material 100 Frame 110 1st support part 111, 112, 121, 122, 126, 201, 202, 301, 302, 601, 602 flat surface 118, 119, 127, 128, 129, 209, 609 Recess 120 Second support part 200, 600 Lead section 300 Die pad section

Claims

1. An annular frame portion having a first support portion; a plurality of lead portions extending from the first support portion to an inside of the frame portion; having The frame portion and the lead portion are The first page and a second surface opposite the first surface; having a plurality of first recesses are formed in the first surface of the first support portion; A lead frame having a second recess formed on the second surface of each of the leads.

2. The lead frame according to claim 1 , wherein the first recess is shallower than the second recess.

3. The first support portion has a first flat surface on the second surface, 3. The lead frame according to claim 1, wherein each of the leads has a second flat surface on the second surface, the second flat surface being continuous with the first flat surface and flush with the first flat surface.

4. the first support portion has a third flat surface parallel to the first flat surface between adjacent first recesses, 4. The lead frame according to claim 3, wherein each of said leads has a fourth flat surface on said first surface, said fourth flat surface being continuous with said third flat surface and being flush with said third flat surface.

5. 3. The lead frame according to claim 1, further comprising a die pad portion provided inside the frame portion.

6. a die pad portion provided inside the frame portion, The die pad portion is A fifth flat surface that is flush with the third flat surface; A sixth flat surface that is flush with the first flat surface; The lead frame of claim 4 , comprising:

7. The first support portion extends in a first direction, the frame portion has a second support portion extending in a second direction perpendicular to the first direction, The lead frame according to claim 1 , wherein a third recess is formed in the first surface of the second support portion.

8. The method includes a step of performing wet etching on a metal plate having a first surface and a second surface opposite to the first surface to form an annular frame having a first support portion and a plurality of lead portions extending from the first support portion to an inside of the frame portion, A method for manufacturing a lead frame, in which the wet etching involves supplying an etching liquid to the first surface and the second surface with the first surface facing vertically downward and the second surface facing vertically upward, forming a plurality of first recesses in the first surface of the first support portion, and forming second recesses in the second surface of each of the lead portions.

9. The method for manufacturing a lead frame according to claim 8 , wherein the first recess is formed shallower than the second recess.

10. The first support portion extends in a first direction, the frame portion has a second support portion extending in a second direction perpendicular to the first direction, The method for manufacturing a lead frame according to claim 8 , wherein the wet etching forms a third recess in the first surface of the second support portion.

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