TWI381507B - Manufacturing method of lead frame - Google Patents

Description

Lead frame manufacturing method

The present invention relates to a method of manufacturing a lead frame, and more particularly to a method of manufacturing a lead frame having a protective structure.

With the continuous advancement of technology, light-emitting diodes (LEDs) have been widely used in various fields of lighting, lamps and the like. The solid-state lighting of the light-emitting diode has the advantages of small volume, good luminous efficiency, long life, high reliability, not easy to break, no heat radiation, no mercury pollution, low energy consumption, etc., and is not only energy-saving, environmentally friendly and safe lighting, but also Because of its high chroma characteristics, it has also become a generation of backlight sources under the flat-panel display, and has become an important research field of production, education and research in various countries, and is also a star industry that has attracted much attention.

In the use of a general light-emitting diode, the light-emitting diode system is fixed on a metal bracket, and the metal bracket is used to connect the electrical signal/control signal and heat dissipation. The metal bracket is provided with a wafer mold base for the solid crystal of the light-emitting diode and the subsequent resin packaging process.

However, since the manufacture of the wafer mold base is made by the injection molding method on the metal bracket by the plastic injection mold, and the rubber stopper structure on the mold is used to block the plastic flow to the gap between the conductive terminals, but the plastic is injected. The resulting turbulent flow of the liquid plastic and the injection pressure may cause structural deformation of the wafer mold base. In addition, in the above-described process of injection molding, there may be cases where the broken position is unstable, and the glue or the like is improperly caused.

On the other hand, since the metal objects such as the conductive terminals may be directly contacted by the plastic injection mold, the metal surface is scratched, which affects the quality of the conductive terminals on the current or signal.

The reason is that the inventors have felt that the above-mentioned deficiency can be improved, and proposes a present invention which is rational in design and effective in improving the above-mentioned deficiency.

The main object of the present invention is to provide a method for manufacturing a lead frame, which is to fill a bare space between adjacent conductive terminals in an ejection step to reinforce the strength of the wafer carrier during blanking. , thereby improving the quality of the lead frame strip produced.

In order to achieve the above object, the present invention provides a method for manufacturing a lead frame, the steps are as follows: First, a stamping step is performed on a substrate to form a plurality of lead frames on the substrate, each of the lead frames including at least A functional area and a plurality of conductive terminals are disposed on the two sides of the functional area correspondingly, and a bare space is formed between the adjacent conductive terminals. Then, a plastic material is injected on each of the lead frames to form a wafer carrier on each of the lead frames, and the plastic material is further filled into the bare space between the adjacent conductive terminals. To form a protective structure; next, a bending step is performed to bend the conductive terminals and remove the protective structure.

The invention also provides a method for manufacturing another lead frame, the steps are as follows: a stamping step is performed on a substrate to form a plurality of lead frames, each of the lead frames including at least one functional area and a plurality of conductive lines Terminals, the conductive terminals are correspondingly arranged in two of the functional areas A bare portion is formed between the adjacent conductive terminals, and the conductive terminals are simultaneously bent in the punching step. Then, a plastic material is injected on each of the lead frames to form a wafer carrier, and the plastic material is further filled into the bare space between the adjacent conductive terminals to form a protective structure.

The present invention has the following beneficial effects: the manufacturing method proposed by the present invention, the wafer carrier is formed by an injection method, and a plastic material is filled in a bare space between adjacent conductive terminals to form the protection structure. The structure can increase the strength of the wafer carrier and avoid damage to the surface of the metal object.

For a better understanding of the features and technical aspects of the present invention, reference should be made to the accompanying drawings.

Please refer to the first to third figures. The present invention provides a method for manufacturing a lead frame. The present invention provides a method for manufacturing a lead frame, which is used to manufacture a lead frame 10, which is regularly arranged in a lead frame 10. On the substrate 1, to facilitate the subsequent production process. Each lead frame 10 has a wafer carrier 101 and a plurality of conductive terminals 102 arranged on both sides of the wafer carrier 101, and a bare space 103 is formed between the conductive terminals 102 on the same side of the wafer carrier 101. The bare space portion 103 is filled with a protective structure 105, which can reinforce the strength of the wafer carrier 101 when the material is cut, and the protection structure 105 can avoid the problem of crushing of the conductive terminal 102 or other metal material. its The manufacturing method includes the following steps:

The step (a) provides a substrate 1 which is substantially a metal thin plate and applies a stamping process on the substrate to form the plurality of lead frames 10 on the substrate 1. As shown in the second figure, the substrate 1 includes a plurality of lead frames 10 having a functional area 100 and conductive terminals 102. In the specific embodiment, a plurality of the lead frames 10 are regularly arranged on the lead frame. Each of the lead frames 10 includes a functional area 100 and three sets of conductive terminals 102. The three sets are arranged correspondingly on opposite sides of the functional area 100, and formed between adjacent conductive terminals 102. There is a bare portion 103, and each of the conductive terminals 102 has an outer end 1022 and an inner end 1021.

In addition, the substrate 1 can adopt a substrate sheet of iron or copper, and after the stamping process is performed, the substrate 1 can be further subjected to an electroplating step, for example, an electroplating process including plating copper, nickel plating, silver plating, etc. A better anti-rust effect can be obtained, and the hardness of the lead frame strip can also be increased.

Step (b) ejects a plastic material. Referring to FIG. 2A and FIG. 3 , a wafer carrier 101 is formed on each of the lead frames 10 by using an injection molding technique. The wafer carrier 101 covers the functional area 100 and exposes the functional area. The wafer carrier 101 further exposes the inner end 1021 of the conductive terminals 102 to the inside of the wafer carrier 101, and the outer ends 1022 of the conductive terminals 102 extend and protrude from the wafer carrier 101. The outside. Moreover, in this step, the plastic material is further filled into the bare space 10 between the outer ends 1022 of the adjacent conductive terminals 102. 3, to form a protective structure 105.

In another embodiment, in the specific embodiment, each of the lead frames 10 further includes four fixing legs 104 extending from the functional area 100 to the outside of the wafer carrier 101; and the fixing feet 104 is substantially formed in four corner positions of the wafer carrier 101, and each of the fixing legs 104 and the outer end 1022 of the adjacent conductive terminal 102 are also formed with the bare portion 103 described above, so the protection structure 105 then fills the bare space 103 between the fixed leg 104 and its adjacent conductive terminal 102.

As shown in FIG. 3A to FIG. 3D, in order to achieve a better protection function, the thickness D1 of the protection structure 105 is greater than the thickness D2 of the conductive terminals 102, so that the protection structure 105 can avoid the The metal surfaces of the conductive terminals 102 are crushed by the mold. For example, the thickness D1 of the protective structure 105 is greater than the thickness D2 of the conductive terminals 102, and the protective structure 105 may have various features such as upper convex flat, upper and lower convex, upper flat convex or upper and lower.

Therefore, after the above steps, a plurality of lead frames 10 can be formed on the substrate 1. Each lead frame 10 has a wafer carrier 101 and a plurality of conductive terminals 102 arranged on both sides of the wafer carrier 101. A bare portion 103 is formed between the conductive terminals 102 on the same side of the wafer carrier 101. The bare portion 103 is filled with a protective structure 105, which can avoid the conductive terminals 102 or other metal materials. The problem of crushing.

In the post-process portion, the conductive terminals 102 must be bent to form solder pads; and the protective structure 105 must also be removed. The following describes the three implementations:

Mode 1. The protective structure 105 is removed while the conductive terminals 102 are bent. In other words, in the same step, the conductive terminals 102 are bent at the same time by the tool and the protective structure 105 is broken to remove the protective structure 105 from the wafer carrier 101.

In the second embodiment, the protective structure 105 is removed, and the conductive terminals 102 are bent. In other words, the protective structure 105 is first broken by different process steps, and then the conductive terminals are bent.

In the third embodiment, the conductive terminals 102 are removed first, and then the protection structure 105 is bent.

Therefore, the final formed lead frame strip can be shipped to downstream manufacturers. After the downstream manufacturer cuts off the fixed leg 104 (as shown in the fourth figure), at least one light emitting diode chip can be fixed on the functional area 100 in the wafer carrier 101, and the light emitting diode chip is connected by using the wire. And the conductive terminal 102 is filled into the wafer carrier 101 by using a packaging material, and the LED body and the wire are coated inside the package material to form a light-emitting diode unit.

Please refer to the fifth figure, which is a second embodiment of the present invention, including the following steps (please refer to the sixth figure and the seventh figure at the same time):

The step (a) provides a substrate 1 which is substantially a thin metal plate, and a stamping process is applied to the substrate 1 to form a plurality of lead frames 10 on the substrate 1. As shown in the second figure of the first embodiment, on the substrate 1 The lead frame 10 includes at least one functional area 100 and a conductive terminal 102. In the embodiment, a plurality of the lead frames 10 are regularly arranged on the substrate 1. Each of the lead frames 10 includes a functional area. 100 and three sets of conductive terminals 102 are arranged on the two sides of the functional area 100 corresponding to each other, and a bare space 103 is formed between the adjacent conductive terminals 102. In this step, the conductive terminal 102 is further subjected to press forming; in other words, the stamping step of the present embodiment simultaneously press-forms the substrate 1 and the conductive terminal 102 so that the conductive terminal 102 has a bent structure.

In addition, the substrate 1 can adopt a substrate sheet of iron or copper, and after the stamping process is performed, the substrate 1 can be further subjected to an electroplating step, for example, an electroplating process including plating copper, nickel plating, silver plating, etc. A better anti-rust effect can be obtained, and the hardness of the lead frame strip can also be increased.

Step (b) ejects a plastic material. Referring to FIG. 6 and FIG. 7 , a wafer carrier 101 is formed on each of the lead frames 10 by using an injection molding technique. The wafer carrier 101 covers the functional area 100 and exposes the functional area 100. The inner end 1021 of the conductive terminals 102 is exposed to the inside of the wafer carrier 101, and the outer ends 1022 of the conductive terminals 102 are extended and protruded from the wafer carrier 101. external. Moreover, in this step, the plastic material is further filled into the bare space 103 between the outer ends 1022 of the adjacent conductive terminals 102 to form the protective structure 105.

In another embodiment, in the specific embodiment, each of the lead frames 10 further includes four fixing legs 104 extending from the functional area 100 to the outside of the wafer carrier 101; the four fixing feet 104 is substantially formed at four corner positions of the wafer carrier 101, and each of the fixing legs 104 and the adjacent conductive terminals 102 are also formed with the bare portion 103 described above, so the protective structure 105 is similarly The bare space 103 between the fixed leg 104 and the adjacent conductive terminal 102 is filled.

As shown in the fifth embodiment, as shown in the fifth to fifth figures, in order to achieve a better protection function, the thickness D1 of the protective structure 105 is greater than the thickness D2 of the conductive terminals 102, so that The protective structure 105 protects the metal surface of the conductive terminals 102 from being crushed by the mold, and the protective structure 105 can have various features such as upper convex flat, upper and lower convex, upper flat convex or upper and lower.

Therefore, after the above steps, a substrate 1 having a plurality of lead frames 10 thereon, each lead frame 10 having a wafer carrier 101 and a plurality of conductive terminals 102 arranged on both sides of the wafer carrier 101 can be fabricated. A bare portion 103 is formed between the conductive terminals 102 on the same side of the wafer carrier 101. The bare portion 103 is filled with a protective structure 105. The protective structure 105 can avoid the conductive terminals 102 or other. The problem of crushing of metal parts.

In the post-process portion, after the step of projecting the plastic material forming wafer carrier 101, an extrusion step is further included to remove the protective structure 105.

Finally, the formed lead frame strip can be shipped to downstream manufacturers. After the downstream manufacturer cuts off the fixed leg 104 (as shown in FIG. 8), at least one light emitting diode chip is fixed on the functional area 100 in the wafer carrier 101, and the light emitting diode chip is connected by using a wire. The inner end 1021 of the conductive terminal 102 is filled into the wafer carrier 101 by using a packaging material, so that the light emitting diode wafer and the wire are wrapped inside the package material to form a light emitting diode unit.

The above is only the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Therefore, the equivalents of the present invention and the equivalents of the drawings are all included in the present invention. Within the scope of protection, it is given to Chen Ming.

1‧‧‧Substrate

10‧‧‧ lead frame

100‧‧‧ functional area

101‧‧‧ wafer carrier

102‧‧‧Electrical terminals

1021‧‧‧Inside

1022‧‧‧Outside

103‧‧‧ naked room

104‧‧‧Fixed feet

105‧‧‧Protection structure

D1, D2‧‧‧ meat thick

The first figure is a flow chart of a method of manufacturing a lead frame according to a first embodiment of the present invention.

The second figure is a schematic view of the lead frame strip of the first embodiment of the present invention.

The second A is a schematic view of the portion A of the second figure showing the bare space between the conductive terminals.

The third figure shows a schematic view of the protective structure formed on the bare portion.

The third to third D drawings are the four structural aspects of the protective structure of the present invention.

The fourth figure shows a schematic view of the conductive terminals of the single lead frame of the first embodiment of the present invention after being bent.

The fifth figure is a flow chart of a method for manufacturing a lead frame strip according to a second embodiment of the present invention.

Figure 6 is a schematic view of a lead frame of a second embodiment of the present invention showing bare spaces between the conductive terminals.

The seventh figure shows a schematic view of the protective structure formed on the bare portion.

Figure 8 is a schematic view showing a single lead frame of a second embodiment of the present invention.

The representative diagram of this case is a flow chart, so there is no component symbol description.

Claims (16)

A manufacturing method of a lead frame includes the following steps: applying a stamping step on a substrate, the substrate is formed with a plurality of lead frames, each of the lead frames having a functional area and a plurality of conductive terminals, the conductive terminals Correspondingly arranged on both sides of the functional area, and a bare space is formed between the adjacent conductive terminals, each of the conductive terminals has an outer end and an inner end; and a plastic material is ejected in each Forming a wafer carrier on the lead frame, and the plastic material further fills the bare space between the adjacent conductive terminals to form a protective structure; and performing a bending step to bend The conductive terminals are removed and the protective structure is removed. The method of manufacturing a lead frame according to claim 1, wherein in the punching step, each of the lead frames is further formed with a plurality of fixed legs. The method of manufacturing a lead frame according to claim 2, wherein in the step of ejecting a plastic material, the wafer carrier covers the functional area, and the inner ends of the conductive terminals are exposed to the wafer Inside the carrier, the outer ends of the conductive terminals extend outside the wafer carrier, and between the adjacent outer ends of the conductive terminals and between the outer ends of the conductive terminals adjacent to the fixed pins The bare space is formed, and the plastic material is filled in the bare space to form the protective structure. The method of manufacturing a lead frame according to claim 1, wherein in the step of ejecting a plastic material, the wafer carrier covers the functional area, and the inner ends of the conductive terminals are exposed to the wafer Inside the carrier, the outer ends of the conductive terminals extend outside the wafer carrier, and the bare portions are formed between the adjacent side ends of the adjacent conductive terminals, and the plastic material is filled in the bare space. The protective structure is formed. The method of manufacturing a lead frame according to claim 3, wherein the protective structure has a thickness greater than a thickness of the conductive terminals. The method for manufacturing a lead frame according to claim 5, wherein the protective structure is a structure in which the upper convex portion is flat, the upper and lower sides are convex, the upper flat is convex, or the upper and lower sides are flat. The method of manufacturing a lead frame according to claim 1, wherein in the bending step, the protective structure is removed while bending the conductive terminals. The method of manufacturing a lead frame according to claim 1, wherein in the bending step, the protective structure is removed before the conductive terminals are bent. The method of manufacturing a lead frame according to claim 1, wherein in the bending step, the protective structure is removed after bending the conductive terminals. A method for manufacturing a lead frame, comprising the steps of: applying a stamping step on a substrate to form a plurality of substrates a lead frame, each lead frame has a functional area and a plurality of conductive terminals, the conductive terminals are correspondingly arranged on two sides of the functional area, and a bare space is formed between the adjacent conductive terminals Each of the conductive terminals has an outer end and an inner end, and at the same time, the conductive terminals are bent; and a plastic material is injected on each lead frame to form a wafer carrier, and the plastic material is further The bare space between the adjacent conductive terminals is filled to form a protective structure. The method of manufacturing a lead frame material according to claim 10, wherein in the punching step, each of the lead frames is further formed with a plurality of fixed legs. The method of manufacturing a lead frame according to claim 11, wherein in the step of ejecting a plastic material, the wafer carrier covers the functional area, and the inner ends of the conductive terminals are exposed to the Inside the wafer carrier, the outer ends of the conductive terminals extend outside the wafer carrier, and the outer ends of the adjacent conductive terminals and the outer ends of the conductive terminals adjacent to the fixed pins The bare space is formed therebetween, and the plastic material is filled in the bare space to form the protective structure. The method of manufacturing a lead frame according to claim 10, wherein in the step of ejecting a plastic material, the wafer carrier covers the functional area, and the inner ends of the conductive terminals are exposed to the wafer Inside the carrier, the outer ends of the conductive terminals extend outside the wafer carrier, and adjacent to the adjacent conductive terminals The bare space is formed between the side ends, and the plastic material is filled into the bare space to form the protective structure. The method of manufacturing a lead frame according to claim 12, wherein the protective structure has a thickness greater than a thickness of the conductive terminals. The method for manufacturing a lead frame according to claim 14, wherein the protective structure is a structure in which the upper convex portion is flat, the upper and lower sides are convex, the upper flat is convex, or the upper and lower sides are flat. The method of manufacturing a lead frame material according to claim 10, wherein after the step of ejecting a plastic material, an extrusion step is further included to remove the protective structure.