Lead frame and method for manufacturing a lead frame

Abstract

To improve productivity of a lead frame.SOLUTION: A lead frame includes a die pad, a lead placed around the die pad, and a support bar that supports the die pad. The support bar, on one main surface, includes a covering portion covered with acicular oxide, and an exposed portion not covered by a needle-like oxide. Further, in the support bar, the exposed portion is arranged at a bent portion that is inclined in side view with respect to the lead.SELECTED DRAWING: Figure 2

Description

【Technical Field】 【0001】 The disclosed embodiments relate to a lead frame and a method for manufacturing a lead frame. 【Background Art】 【0002】 A semiconductor device includes, for example, a lead frame, a semiconductor chip mounted thereon, and a sealing resin for sealing the semiconductor chip. In the manufacturing process of such a semiconductor device, the lead frame and the semiconductor chip mounted thereon are covered with a thermosetting resin and heated to cure it. 【0003】 In addition, in order to improve the reliability of a semiconductor device, a technique for improving the adhesion between a lead frame and a sealing resin by forming needle-like oxides on the surface of the lead frame is known (see Patent Document 1). 【Prior Art Documents】 【Patent Documents】 【0004】 【Patent Document 1】 Japanese Patent Application Laid-Open No. 3-295262 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0005】 In addition, in a semiconductor device, a technique is used in which a support bar supporting a die pad is bent to change the height of the die pad and the height of the lead. However, in the above conventional technique, when the support bar is bent, needle-like oxides easily adhere to the mold or oxides that have fallen off accumulate on the mold. Therefore, it is necessary to frequently clean the mold on which the needle-like oxides have accumulated. As a result, there is a risk that the productivity of the lead frame will decrease. 【0006】 One aspect of the embodiment has been made in view of the above, and an object thereof is to provide a lead frame and a method for manufacturing a lead frame that can improve productivity. [Means for solving the problem] 【0007】 A lead frame according to one embodiment comprises a die pad, leads arranged around the die pad, and a support bar supporting the die pad. The support bar has a coated portion covered with needle-shaped oxide and an exposed portion not covered with the needle-shaped oxide on one of its main surfaces. The exposed portion is located at a bent portion of the support bar that is inclined in a side view relative to the leads. 【0008】 A method for manufacturing a lead frame according to one embodiment includes the steps of forming a pattern, forming a covering portion, forming an exposed portion, and bending. The pattern forming step involves forming a pattern on a metal plate that includes a die pad, leads arranged around the die pad, and a support bar that supports the die pad. The covering portion forming step involves forming a covering portion covered with needle-shaped oxide on one main surface of the support bar. The exposed portion forming step involves removing a portion of the covering portion formed on the one main surface with a laser to form an exposed portion. The bending step involves bending the support bar so that the portion where the exposed portion is provided is inclined relative to the leads in a side view. [Effects of the Invention] 【0009】 According to one embodiment, the productivity of lead frames can be improved. [Brief explanation of the drawing] 【0010】 [Figure 1A] Figure 1A is a schematic diagram of a lead frame according to an embodiment. [Figure 1B] Figure 1B is a cross-sectional view of a semiconductor device according to an embodiment. [Figure 1C] Figure 1C is a cross-sectional view taken along the line AA shown in Figure 1A. [Figure 2]Figure 2 is a flowchart showing an example of the manufacturing process for a lead frame according to this embodiment. [Figure 3A] Figure 3A is a diagram illustrating the oxide formation process according to the embodiment. [Figure 3B] Figure 3B is a diagram illustrating the oxide removal process according to the embodiment. [Figure 3C] Figure 3C is a diagram illustrating the bending process according to the embodiment. [Modes for carrying out the invention] 【0011】 The lead frame and the method for manufacturing the lead frame disclosed herein will be described below with reference to the attached drawings. However, the embodiments described below do not limit this disclosure. 【0012】 Furthermore, it should be noted that drawings are schematic representations, and the dimensional relationships and proportions of each element may differ from reality. Moreover, there may be discrepancies in dimensional relationships and proportions between drawings themselves. 【0013】 <Lead frames and semiconductor devices> First, the lead frame 1 and semiconductor device 100 according to the embodiment will be described with reference to Figures 1A to 1C. Figure 1A is a schematic diagram of the lead frame 1 according to the embodiment, and Figure 1B is a cross-sectional view showing the semiconductor device 100 according to the embodiment. 【0014】 The lead frame 1 shown in Figure 1A is a lead frame used in the manufacture of a QFP (Quad Flat Package) type semiconductor device 100. The technology of this disclosure may also be applied to lead frames used in the manufacture of other types of semiconductor devices, such as SOP (Small Outline Package). 【0015】 The lead frame 1 according to the embodiment has, for example, a strip shape in plan view, and a plurality of unit lead frames 10 are arranged side by side along the longitudinal direction. Such a unit lead frame 10 is a part corresponding to each semiconductor device 100 manufactured using the lead frame 1. Note that a plurality of unit lead frames 10 may be arranged side by side not only along the longitudinal direction of the lead frame 1 but also along the width direction. 【0016】 As shown in FIG. 1A, the unit lead frame 10 has a die pad 11, a plurality of leads 12, a plurality of support bars 13, and a dam bar 14. Although not shown in FIG. 1A, pilot holes may be provided side by side on the side surface of the long side of the lead frame 1. 【0017】 The die pad 11 is provided, for example, at the central portion of the unit lead frame 10. As shown in FIG. 1B, a semiconductor element 101 can be mounted on the front surface side of such a die pad 11. 【0018】 The die pad 11 is connected to the outer edge of the unit lead frame 10 by a plurality of support bars 13 and is supported by the unit lead frame 10. Such a plurality of support bars 13 are connected to the four corners of the die pad 11, for example. 【0019】 The plurality of leads 12 are arranged side by side around the die pad 11, and the tip portions 12a of each extend from the outer edge of the unit lead frame 10 toward the die pad 11. Such a lead 12 functions as a connection terminal of the semiconductor device 100 as shown in FIG. 1B. 【0020】 The lead 12 has a tip portion 12a and a base portion 12b. As shown in FIG. 1B, in the semiconductor device 100, a bonding wire 102 made of Cu, a Cu alloy, Au, an Au alloy, or the like is connected to the tip portion 12a of the lead 12. Therefore, high bonding characteristics with the bonding wire 102 are required for the lead frame 1. The dam bar 14 connects between adjacent leads 12. 【0021】 In addition to the lead frame 1, semiconductor element 101, and bonding wire 102, the semiconductor device 100 has a sealing resin 103. The sealing resin 103 is made of, for example, an epoxy resin and is molded into a predetermined shape by a molding process or the like. The sealing resin 103 seals the surfaces of the semiconductor element 101, bonding wire 102, die pad 11, and the tip portion 12a of the lead 12. 【0022】 Also, the base end portion 12b of the lead 12 functions as an external terminal (outer lead) of the semiconductor device 100 and is soldered to the substrate. In the semiconductor device 100 of the type where the back surface of the die pad 11 is exposed from the sealing resin 103 or the type provided with a heat slug, their back surfaces are soldered to the substrate. 【0023】 Note that the dam bar 14 has a function of a dam to prevent the resin used from leaking to the base end portion 12b (outer lead) side in the molding process of molding the sealing resin 103, and is finally cut in the manufacturing process of the semiconductor device 100. 【0024】 Also, in the lead frame 1 according to the embodiment, a plating layer 3 is formed on the tip portion 12a of the die pad 11 and the lead 12. Such a plating layer 3 is composed of, for example, Ag (silver) as a main component. 【0025】 Thereby, the joining of the lead frame 1 and the bonding wire 102 can be facilitated. 【0026】 FIG. 1C is a cross-sectional view taken along the line A-A shown in FIG. 1A, and is a view showing the cross-sectional structure of the die pad 11 and support bar 13 of the lead frame 1. We have provided the translation of the text you provided. If you have any other questions or need further assistance, please feel free to let us know. 【0027】 As shown in Figure 1C, the lead frame 1 according to this embodiment comprises a base material 2 and a plating layer 3. The base material 2 is made of a conductive material (for example, a metallic material such as copper or a copper alloy). The plating layer 3 is formed on the main surface 2a of the base material 2 and is a plating layer mainly composed of, for example, Ag. 【0028】 Furthermore, at least one undercoat plating layer, mainly composed of Cu, Ni, Pd, Au, Ag, etc., may be formed between the substrate 2 and the plating layer 3 for the purpose of preventing metal diffusion and improving heat resistance. Alternatively, a plating layer mainly composed of Au, Pt, Pd, Ag, etc., may be formed on the surface of the plating layer 3. 【0029】 As shown in Figure 1C, the support bar 13 has a base end 21, a flat portion 22, and a bent portion 23. The base end 21 is connected to the outer edge of the unit lead frame 10, as shown in Figure 1A. The flat portion 22 is located between the base end 21 and the bent portion 23 and is a flat portion having approximately the same height as the lead 12 (see Figure 1A). 【0030】 The bent portion 23 is located, for example, at or near the tip of the support bar 13 and is inclined with respect to the lead 12 (i.e., with respect to the flat portion 22) toward the main surface 2b of the base material 2. As a result, the die pad 11 protrudes toward the main surface 2b of the base material 2 relative to the lead 12. 【0031】 In this embodiment, the support bar 13 has exposed portions 32 on the main surface 2a, specifically on the bent portion 23 and the flat portion 22a adjacent to the outside of the bent portion 23. That is, the support bar 13 has exposed portions 32 in the region P on the main surface 2a side shown in Figure 1C. 【0032】 On the other hand, the support bar 13 has a covering portion 31 in areas other than the main surface 2a side region P shown in Figure 1C (for example, the base end portion 21 and the flat portion 22b located between the base end portion 21 and the flat portion 22a). 【0033】 The coated portion 31 is the area where the main surface 2a of the substrate 2 is covered with needle-shaped oxide 4 (see Figure 3A). The needle-shaped oxide 4 is, for example, needle-shaped copper oxide. The exposed portion 32 is the area where the main surface 2a of the substrate 2 is not covered with needle-shaped oxide 4, and the substrate 2 is exposed. 【0034】 In this way, by arranging needle-shaped oxides 4 on the main surface 2a of the substrate 2, the adhesion between the lead frame 1 and the sealing resin 103 (see Figure 1B) can be improved. Therefore, according to this embodiment, the reliability of the semiconductor device 100 can be improved. 【0035】 In this embodiment, needle-shaped oxides 4 may be arranged on at least a portion of the main surface 2b of the substrate 2. This further improves the adhesion between the lead frame 1 and the sealing resin 103. 【0036】 Furthermore, in this embodiment, the exposed portion 32 is positioned on the bent portion 23 of the main surface 2a of the support bar 13. In other words, in this embodiment, the needle-shaped oxide 4 is not provided on the bent portion 23 on the main surface 2a side. 【0037】 This prevents the needle-shaped oxides 4 on the bent portion 23 from being scraped off by the punch 41 and adhering to the punch 41 when the punch 41 (see Figure 3C) is pressed against the main surface 2a to form a bent portion 23 in the substrate 2. 【0038】 Therefore, according to this embodiment, the frequency of cleaning the needle-shaped oxides 4 deposited on the punch 41 can be reduced, thereby improving the productivity of the lead frame 1. 【0039】 Furthermore, in this embodiment, it is preferable that the exposed portion 32 be positioned on the flat portion 22a adjacent to the bent portion 23 on the main surface 2a of the support bar 13. In other words, in this embodiment, it is preferable that the needle-shaped oxide 4 is not provided on the flat portion 22a on the main surface 2a side. 【0040】 This makes it possible to suppress the adhesion of needle-shaped oxides 4 on the flat portion 22a that comes into contact with the stripper 43 to the stripper 43 when forming the bent portion 23 on the substrate 2 while supporting the substrate 2 with the stripper 43 (see Figure 3C). 【0041】 Therefore, according to this embodiment, the frequency of cleaning the needle-shaped oxides 4 deposited on the stripper 43 can be reduced, thereby further improving the productivity of the lead frame 1. 【0042】 Furthermore, in this embodiment, the exposed portion 32 may have an uneven surface. This improves the adhesion between the lead frame 1 and the sealing resin 103 at the exposed portion 32. Therefore, according to this embodiment, the reliability of the semiconductor device 100 can be improved. 【0043】 The uneven surface shape of the exposed portion 32 can be formed, for example, by the heat generated when the oxide is removed by laser irradiation to form the exposed portion 32 during the manufacturing process of the lead frame 1 shown below. 【0044】 <Lead frame manufacturing process> Next, the manufacturing process of the lead frame 1 according to the embodiment will be described with reference to Figures 2 to 3C. Figure 2 is a flowchart showing an example of the steps in the manufacturing process of the lead frame 1 according to the embodiment. Note that in the manufacturing process shown below, the illustration of the plating layer 3 and the explanation of the process for forming the plating layer 3 will be omitted. 【0045】 As shown in Figure 2, first, a pattern forming process is performed to form a pattern on a metal plate that includes a die pad 11 (see Figure 1A), a lead 12 (see Figure 1A), and a support bar 13 (see Figure 1A) (step S1). Such a pattern is, for example, the pattern shown in Figure 1A in plan view. 【0046】 This pattern formation process may be carried out by etching the metal plate or by stamping the metal plate. 【0047】 Next, an oxide formation process is performed on the metal plate on which a predetermined pattern has been formed (step S2). Figure 3A is a diagram illustrating the oxide formation process according to the embodiment. As shown in Figure 3A, in the oxide formation process according to the embodiment, needle-shaped oxides 4 are formed on the main surface 2a of the substrate 2, and a coating portion 31 is provided on the main surface 2a. 【0048】 Such needle-shaped oxides 4 can be formed, for example, by immersing a substrate 2 in a strongly oxidizing alkaline solution, connecting the anode side of a rectifier to the substrate 2, and connecting the cathode side to an electrode plate placed in a solution tank, and performing anodic oxidation. The needle-shaped oxides 4 formed in this way contain cuprous oxide (Cu2O) and cupric oxide (CuO), and do not necessarily have a layered structure. 【0049】 Returning to the explanation of Figure 2, in the manufacturing process of the lead frame 1 according to this embodiment, an oxide removal step is performed following the oxide formation step (step S3). Figure 3B is a diagram illustrating the oxide removal step according to this embodiment. 【0050】 As shown in Figure 3B, in the oxide removal process according to this embodiment, a spot-shaped laser L is irradiated onto predetermined locations on the main surface 2a of the substrate 2. Specifically, the spot-shaped laser L is irradiated onto the portion of the main surface 2a of the substrate 2 corresponding to the bent portion 23 (see Figure 3C) and the portion corresponding to the flat portion 22a (see Figure 3C). 【0051】 As a result, as shown in Figure 3B, the needle-shaped oxide 4 is removed in the area corresponding to the bent portion 23 and the area corresponding to the flat portion 22a, and the exposed portion 32 is formed. 【0052】 In this embodiment, the wavelength of the laser L is preferably 1000 nm to 1100 nm. By setting the wavelength of the laser L within this range, the absorption rate of the laser L for the needle-shaped oxide 4 can be made higher than the absorption rate of the laser L for Cu, the main component of the substrate 2, and for Ag, the main component of the plating layer 3. 【0053】 Therefore, according to this embodiment, the needle-shaped oxide 4 can be efficiently removed by the laser L, and the alteration of areas where the needle-shaped oxide 4 is not present (for example, areas where the substrate 2 is exposed, or areas where the plating layer 3 is placed) by the laser L can be suppressed. 【0054】 In this disclosure, it was confirmed that by irradiating the needle-shaped oxide 4 with a laser L under the following conditions, the needle-shaped oxide 4 is removed and an exposed portion 32 is formed on the main surface 2a of the substrate 2. Equipment: KEYENCE MD-X2500 laser marker Laser wavelength: 1064 (nm) Laser power: 80% Scan speed: 1000 (mm / s) Pulse frequency: 80 (kHz) Spot variable: -40 Number of prints: 1 (times) Quality adjustment level: Standard Type: Fill Pattern: Cross Direction: Alternate Fill line spacing: 0.030 (mm) 【0055】 It is generally known that the glossy surfaces of metals (such as Cu and Ag) have low absorption of laser light, while oxides have high absorption. Based on this, the inventors of this application have diligently discovered that a laser wavelength of 1000 to 1100 nm is preferable, as it allows for the removal of the oxide film formed on the lead frame while minimizing the impact on the substrate 2 and the plating layer 3. 【0056】 Returning to the explanation of Figure 2, in the manufacturing process of the lead frame 1 according to this embodiment, a bending process is performed following the oxide removal process (step S4). Figure 3C is a diagram illustrating the bending process according to this embodiment. 【0057】 As shown in Figure 3C, a base material 2, having an exposed portion 32 and a covered portion 31 formed on its main surface 2a, is placed between the punch 41 and the die plate 42. The die plate 42 has a recess 42a formed therein that has a shape complementary to the shape of the punch 41. 【0058】 The punch 41 is inserted into the recess 42a of the die plate 42 while pressing the base material 2 downwards. At this time, the base material 2 is fixed in place by being sandwiched between the stripper 43, which is positioned around the punch 41, and the outer peripheral portion 42b that forms the recess 42a of the die plate 42. 【0059】 As the punch 41 descends, the support bar 13 bends, causing the die pad 11 of the base material 2 to protrude downward and be pressed against the bottom of the recess 42a of the die plate 42. This bending process forms a bent portion 23 on the support bar 13. 【0060】 Alternatively, instead of the punch 41 descending, the die plate 42 may rise to perform the bending process described above. Or, the punch 41 may descend while the die plate 42 rises to perform the bending process described above. 【0061】 In this way, a lead frame 1 having a die pad 11 protruding toward the main surface 2b is obtained, and the manufacturing process of the lead frame 1 according to the embodiment is completed. 【0062】 In this embodiment, as described above, the exposed portion 32 is positioned in the area of ​​the main surface 2a corresponding to the bent portion 23. This prevents the needle-shaped oxide 4 on the bent portion 23 from being scraped off by the punch 41 and adhering to the punch 41 when the punch 41 is pressed against the main surface 2a to form the bent portion 23 in the substrate 2. 【0063】 Therefore, according to this embodiment, the frequency of cleaning the needle-shaped oxides 4 deposited on the punch 41 can be reduced, thereby improving the productivity of the lead frame 1. 【0064】 Furthermore, in this embodiment, the exposed portion 32 is positioned on the flat portion 22a adjacent to the bent portion 23 on the main surface 2a of the support bar 13. This makes it possible to suppress the adhesion of needle-shaped oxides 4 on the flat portion 22a that come into contact with the stripper 43 when forming the bent portion 23 on the base material 2 while supporting the base material 2 with the stripper 43. 【0065】 Therefore, according to this embodiment, the frequency of cleaning the needle-shaped oxides 4 deposited on the stripper 43 can be reduced, thereby further improving the productivity of the lead frame 1. 【0066】 For example, in this disclosure, the productivity of lead frame 1 was 30% when the oxide removal process was not performed, but by performing the oxide removal process, the productivity of lead frame 1 could be improved to 82%. 【0067】 Furthermore, this disclosure confirms that there is no change in the heat resistance of the semiconductor device 100 (see Figure 1B) (i.e., the absence of peeling of the oxide film on the substrate generated by the heat during the assembly process of the semiconductor device 100) between the case where the oxide removal process is not performed and the case where the oxide removal process is performed. 【0068】 Furthermore, this disclosure confirms that there are no morphological changes, etc., to the plated layer 3 and substrate 2 that were mistakenly irradiated with the laser L, in both cases: when the oxide removal process is not performed and when the oxide removal process is performed. 【0069】 Furthermore, this disclosure confirms that there is no change in the adhesion of the bonding wire 102 (see Figure 1B) to the plating layer 3 that was mistakenly irradiated with the laser L, whether the oxide removal process is not performed or is performed. 【0070】 Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention. For example, in the above embodiments, an example was shown in which the substrate 2 is exposed in the exposed portion 32, but the present disclosure is not limited to such an example, and a substance other than the needle-shaped oxide 4 may be attached to the exposed portion 32. 【0071】 Furthermore, although the above embodiment describes a semiconductor device 100 in which the main surface 2b side of the die pad 11 is not exposed from the sealing resin 103, the present disclosure is not limited to such an example, and the main surface 2b side of the die pad 11 may be exposed from the sealing resin 103. This can improve the heat dissipation of the semiconductor element 101. 【0072】 In this case, it is preferable that needle-shaped oxides 4 are not provided on the main surface 2b side of the lead frame 1. This is because, in the sealing process in which the die pad 11 etc. is sealed with sealing resin 103, the needle-shaped oxides 4 prevent sufficient contact between the mold and the main surface 2b side of the die pad 11, causing the sealing resin 103 to leak to the main surface 2b side and preventing sufficient exposure of the die pad 11. 【0073】 As described above, the lead frame 1 according to this embodiment comprises a die pad 11, leads 12 arranged around the die pad 11, and a support bar 13 that supports the die pad 11. The support bar 13 has a covered portion 31 on one main surface 2a that is covered with needle-shaped oxide 4, and an exposed portion 32 that is not covered with needle-shaped oxide 4. In addition, the exposed portion 32 is arranged on the bent portion 23 of the support bar 13 that is inclined in a side view relative to the leads 12. This makes it possible to improve the productivity of the lead frame 1. 【0074】 Furthermore, in the lead frame 1 according to this embodiment, an exposed portion 32 is provided on the flat portion 22a adjacent to the outside of the bent portion 23 of the support bar 13. This further improves the productivity of the lead frame 1. 【0075】 Furthermore, in the lead frame 1 according to this embodiment, the exposed portion 32 has an uneven surface shape. This improves the reliability of the semiconductor device 100. 【0076】 Furthermore, the manufacturing method of the lead frame 1 according to the embodiment includes a step of forming a pattern (step S1), a step of forming a covering portion 31 (step S2), a step of forming an exposed portion 32 (step S3), and a bending step (step S4). The step of forming a pattern (step S1) involves forming a pattern on a metal plate that includes a die pad 11, leads 12 arranged around the die pad 11, and a support bar 13 that supports the die pad 11. The step of forming the covering portion 31 (step S2) involves forming a covering portion 31 covered with needle-shaped oxide 4 on one main surface 2a of the support bar 13. The step of forming the exposed portion 32 (step S3) involves removing a part of the covering portion 31 formed on one main surface 2a with a laser L to form an exposed portion 32. The bending step (step S4) involves bending the support bar 13 so that the portion where the exposed portion 32 is provided is inclined with respect to the leads 12 in a side view. This makes it possible to improve the productivity of the lead frame 1. 【0077】 Furthermore, in the manufacturing method of the lead frame 1 according to the embodiment, the step of forming the exposed portion 32 (step S3) also forms the exposed portion 32 on the flat portion 22a adjacent to the outside of the bent portion 23 that is inclined in a side view with respect to the lead 12. This makes it possible to further improve the productivity of the lead frame 1. 【0078】 Furthermore, in the method for manufacturing the lead frame 1 according to this embodiment, the laser L has a wavelength of 1000 nm to 1100 nm. This allows for efficient removal of needle-shaped oxides 4 by the laser L, while also suppressing alteration of areas where needle-shaped oxides 4 are not present (for example, areas where the substrate 2 is exposed, or areas where the plating layer 3 is placed) by the laser L. 【0079】 Further effects and modifications can be readily derived by those skilled in the art. Therefore, broader aspects of the present invention are not limited to the specific details and representative embodiments expressed and described above. Accordingly, various modifications are possible without departing from the spirit or scope of the overall concept of the invention as defined by the appended claims and their equivalents. [Explanation of Symbols] 【0080】 1 Lead frame 2 Base material 2a Main surface (an example of one of the main surfaces) 3 Plating layer 4 Needle-shaped oxides 11 Die Pad 12 Reeds 13 Support Bar 21 Proximal end 22, 22a, 22b flat part 23. Bending section 31 Covering part 32 Exposed part L Laser

Claims

[Claim 1] Die pad and, Leads arranged around the die pad, A support bar that supports the die pad, Equipped with, The support bar has, on one main surface, a coated portion in which the substrate is covered with needle-shaped oxides, and an exposed portion in which the substrate is exposed. In the support bar, the exposed portion is positioned at the bent portion that is inclined in a side view relative to the lead. Lead frame. [Claim 2] In the support bar, the exposed portion is positioned on the flat portion adjacent to the outside of the bent portion. The lead frame according to claim 1. [Claim 3] A die pad and Leads arranged around the die pad, A support bar that supports the die pad, Equipped with, The support bar has, on one main surface, a coated portion covered with needle-shaped oxide and an exposed portion not covered with the needle-shaped oxide. In the support bar, the exposed portion is positioned at the bent portion that is inclined in a side view relative to the lead. The exposed portion has an uneven surface. Lead frame. [Claim 4] A process of forming a pattern on a metal plate that includes a die pad, leads arranged around the die pad, and a support bar that supports the die pad, The process involves forming a coating portion on one main surface of the support bar, which is covered with needle-shaped oxides. A step of removing a portion of the covering formed on one of the main surfaces with a laser to form an exposed portion, The steps include bending the support bar so that the portion where the exposed part is provided is inclined in a side view with respect to the lead, A method for manufacturing a lead frame, including the lead frame itself. [Claim 5] The process of forming the exposed portion also includes forming the exposed portion on a flat portion adjacent to the outside of the bent portion that is inclined in a side view with respect to the lead. A method for manufacturing a lead frame according to claim 4. [Claim 6] The laser has a wavelength of 1000 nm to 1100 nm. A method for manufacturing a lead frame according to claim 4 or 5.

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