JP2005142333A - Method of manufacturing lead frame - Google Patents

Method of manufacturing lead frame Download PDF

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JP2005142333A
JP2005142333A JP2003376708A JP2003376708A JP2005142333A JP 2005142333 A JP2005142333 A JP 2005142333A JP 2003376708 A JP2003376708 A JP 2003376708A JP 2003376708 A JP2003376708 A JP 2003376708A JP 2005142333 A JP2005142333 A JP 2005142333A
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lead frame
roller
manufacturing
base material
frame base
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JP4383828B2 (en
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Shinji Honda
真二 本田
Takahiro Ishibashi
貴弘 石橋
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Mitsui High Tec Inc
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Mitsui High Tec Inc
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a lead frame which generates no metal strip from a lead frame in a post-process by crushing ends of a thin metal bar after an etching process in manufacturing the lead frame. <P>SOLUTION: In the method of manufacturing the lead frame wherein the thin metal bar formed with a resist film is dipped in an etchant to form a prescribed pattern, a lead frame base material 11 which has finished with etching process is passed between rollers 15 and 16 which are located opposite to each other to crush the end parts in the width direction of the material. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、所定のパターンがエッチング処理によって製造されたリードフレームの製造方法に関する。 The present invention relates to a method for manufacturing a lead frame in which a predetermined pattern is manufactured by an etching process.

図3(A)に示すように、半導体装置に用いるリードフレーム50は、例えば銅又は銅合金等からなる薄板金属条材51の表裏面に、図3(B)に示すように、所定のパターンを形成したレジスト膜52、53が形成された状態でエッチング液に浸漬されて製造される。なお、特許文献1にも、同様な方法で製造したリードフレームが開示されている。 As shown in FIG. 3A, a lead frame 50 used in a semiconductor device has a predetermined pattern on the front and back surfaces of a thin metal strip 51 made of, for example, copper or a copper alloy, as shown in FIG. The resist films 52 and 53 formed with the film are dipped in an etching solution in a state where the resist films 52 and 53 are formed. Patent Document 1 also discloses a lead frame manufactured by a similar method.

特公平7−50765号公報Japanese Patent Publication No. 7-50765

しかしながら、薄板金属条材51の端部は図3(B)に示すように、一般にレジスト膜は形成されず、露出しているので、エッチング液に浸漬した場合、図3(C)に示すように、端部に表裏面方向に徐々に薄くなった中央窪みの凹部54が形成される。
この凹部54はそのまま放置すると、搬送の途中や別工程(例えば、めっき処理や洗浄処理)でこの薄くなった部分が外れて、図3(D)に示すように、ヒゲ状の金属片55が発生し製品に付着したりする等の問題が発生する。特に、近年においては、リードフレームのファインピッチ化が進み、非常に微細な金属片もリードショートを発生させる原因となる。
However, as shown in FIG. 3B, the end portion of the sheet metal strip 51 is generally exposed without being formed with a resist film. Therefore, when immersed in an etching solution, as shown in FIG. In addition, a concave portion 54 having a central recess that is gradually thinned in the front and back direction is formed at the end.
If the concave portion 54 is left as it is, the thinned portion is removed in the middle of conveyance or in another process (for example, plating treatment or cleaning treatment), and as shown in FIG. Problems that occur and adhere to the product occur. In particular, in recent years, lead frames have become finer, and very fine metal pieces also cause lead shorts.

本発明はかかる事情に鑑みてなされたもので、リードフレームの製造工程でエッチング処理後の薄板金属条材の端部を押し潰して、後工程でリードフレームから金属片が発生しないリードフレームの製造方法を提供することを目的とする。 The present invention has been made in view of such circumstances. The lead frame is manufactured by crushing the end of the sheet metal strip after the etching process in the lead frame manufacturing process so that no metal pieces are generated from the lead frame in the subsequent process. It aims to provide a method.

前記目的に沿う請求項1記載のリードフレームの製造方法は、レジスト膜が形成された薄板金属条材をエッチング液に浸漬して所定のパターンを形成するリードフレームの製造方法において、
エッチング処理が完了したリードフレーム基材を、対向配置されたローラの間を通過させて、その幅方向端部を押し潰している。
これによって、リードフレーム基材の両端に形成されるエッジ部分が押し潰されて、鈍化し、その後の処理で剥離しなくなる。
The lead frame manufacturing method according to claim 1, wherein the lead frame manufacturing method according to claim 1, wherein a predetermined pattern is formed by immersing a thin metal strip on which a resist film is formed in an etching solution.
The lead frame base material that has been subjected to the etching process is passed between rollers arranged to face each other, and the widthwise ends thereof are crushed.
As a result, the edge portions formed at both ends of the lead frame base material are crushed and blunted, and do not peel off in subsequent processing.

また、請求項2記載のリードフレームの製造方法は、請求項1記載のリードフレームの製造方法において、前記ローラは軸方向の両側にフランジ部を有する溝形ローラであって、前記リードフレーム基材を前記ローラの溝部に嵌入させて、前記リードフレーム基材の端部処理を行う。
これによって、リードフレーム基材の端部はローラの両側のフランジ部に挟まれて拘束されるので、逃げが無くなり、端部処理が安定して行える。
The lead frame manufacturing method according to claim 2 is the lead frame manufacturing method according to claim 1, wherein the roller is a grooved roller having flange portions on both sides in the axial direction, and the lead frame base material Is inserted into the groove of the roller, and the end portion of the lead frame substrate is processed.
As a result, the end portion of the lead frame base material is sandwiched and restrained by the flange portions on both sides of the roller, so that there is no escape and the end processing can be performed stably.

そして、請求項3記載のリードフレームの製造方法は、請求項1及び2記載のリードフレームの製造方法において、前記ローラは弾性部材又はシリンダーによって、前記リードフレーム基材の内側に付勢されている。
これによって、リードフレーム基材の幅に多少のバラツキがあっても、ローラが弾性部材又はシリンダーによってリードフレーム基材の端部に押しつけられるので、押し潰し処理が確実に行える。
The lead frame manufacturing method according to claim 3 is the lead frame manufacturing method according to claim 1 or 2, wherein the roller is biased to the inside of the lead frame base material by an elastic member or a cylinder. .
Thus, even if there is some variation in the width of the lead frame base material, the roller is pressed against the end portion of the lead frame base material by the elastic member or the cylinder, so that the crushing process can be performed reliably.

なお、請求項1〜3記載のリードフレームの製造方法において、ローラの材質は金属(例えば、ステンレス、鉄、銅、真鍮)やセラミック等の硬質の材料であってもよいが、これよりも弾性力を有するプラスチック素材(例えば、ナイロン、PP、アクリル、ポリカーボネイト、ABS、強化プラスチック)であってもよい。
ローラの取付け位置を固定する場合には、リードフレーム基材の両端部に形成されたエッジの高さ(中央部の一番低い位置から両側の一番高い位置までの幅方向距離)の0.3〜1倍(更に好ましくは、0.4〜0.8倍)を両側のローラによって押し潰すようにするのがよい。
In the lead frame manufacturing method according to any one of claims 1 to 3, the material of the roller may be a hard material such as metal (for example, stainless steel, iron, copper, brass) or ceramic, but is more elastic than this. It may be a plastic material having strength (for example, nylon, PP, acrylic, polycarbonate, ABS, reinforced plastic).
When fixing the mounting position of the roller, the height of the edge formed at both ends of the lead frame substrate (the distance in the width direction from the lowest position in the center to the highest position on both sides) is 0. 3 to 1 times (more preferably 0.4 to 0.8 times) may be crushed by the rollers on both sides.

請求項1〜3記載のリードフレームの製造方法においては、エッチング処理過程で発生したリードフレーム基材の幅方向端部が押し潰されるので、薄くなった金属片の分離がなくなり、リードフレームの製造不良が無くなり、これによって、最終的な製品の不良率が減少する。
特に、請求項2記載のリードフレームの製造方法は、リードフレーム基材の端部がローラから逃げることなく、端部の押し潰し処理が確実に行える。
そして、請求項3記載のリードフレームの製造方法においては、端部にローラが強制的に押し当てられるので、より確実にリードフレーム基材の端部処理が行える。
In the lead frame manufacturing method according to any one of claims 1 to 3, since the width direction end portion of the lead frame base material generated in the etching process is crushed, there is no separation of the thin metal piece, and the lead frame manufacturing Defects are eliminated, thereby reducing the final product defect rate.
In particular, the lead frame manufacturing method according to claim 2 can reliably perform the crushing process of the end portion without the end portion of the lead frame base material escaping from the roller.
In the lead frame manufacturing method according to the third aspect, since the roller is forcibly pressed against the end portion, the end portion of the lead frame base material can be more reliably processed.

続いて、添付した図面を参照しつつ、本発明を具体化した実施の形態につき説明し、本発明の理解に供する。
ここに、図1は本発明の一実施の形態に係るリードフレームの製造方法を示す斜視図、図2は同リードフレームを製造する装置の断面図である。
Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
FIG. 1 is a perspective view showing a lead frame manufacturing method according to an embodiment of the present invention, and FIG. 2 is a sectional view of an apparatus for manufacturing the lead frame.

図1に示すように、本発明の一実施の形態に係るリードフレームの製造方法を適用する装置10は、エッチング処理後のリードフレーム基材11を搬送するローラコンベア12と、ローラコンベア12の中間位置に配置された押し潰しローラ群13とを有している。
ローラコンベア12は、平行に隙間を有して配置された小径の送りローラ14によって構成され、送りローラ14の一部又は全部が回転駆動されていてもよい。
As shown in FIG. 1, an apparatus 10 to which a lead frame manufacturing method according to an embodiment of the present invention is applied includes a roller conveyor 12 that conveys a lead frame substrate 11 after an etching process, and an intermediate between the roller conveyor 12. The crushing roller group 13 is disposed at the position.
The roller conveyor 12 is constituted by a small-diameter feed roller 14 arranged with a gap in parallel, and a part or all of the feed roller 14 may be rotationally driven.

押し潰しローラ群13は、リードフレーム基材11の左右に所定間隔をおいて配置された複数の右ローラ15と複数の左ローラ16(何れもローラの一例)からなっている。右ローラ15と左ローラ16とは、リードフレーム基材11を中央にして左右対となって対向配置されてもよいし、場合によって千鳥状に配置されてもよい。
右ローラ15及び左ローラ16は、この実施の形態ではプラスチック素材(例えば、ナイロン)等であって、所定位置に設けられた垂直シャフト(図示せず)に回転自由に取付けられている。また、右ローラ15及び左ローラ16は、それぞれ軸方向の両側にフランジ部を有する溝形ローラであって、フランジ間の隙間(溝部)の寸法はリードフレーム基材11の厚みの1.5〜5倍程度がよい。
The crushing roller group 13 includes a plurality of right rollers 15 and a plurality of left rollers 16 (all of which are examples of rollers) disposed on the left and right sides of the lead frame substrate 11 at a predetermined interval. The right roller 15 and the left roller 16 may be arranged to face each other in a left-right pair with the lead frame base material 11 at the center, or may be arranged in a zigzag pattern in some cases.
In this embodiment, the right roller 15 and the left roller 16 are made of a plastic material (for example, nylon) or the like, and are freely attached to a vertical shaft (not shown) provided at a predetermined position. Each of the right roller 15 and the left roller 16 is a grooved roller having flange portions on both sides in the axial direction, and the size of the gap (groove portion) between the flanges is 1.5 to 1.5 of the thickness of the lead frame substrate 11. About 5 times is good.

右ローラ15及び左ローラ16の間隔は、図2に示すように、右ローラ15及び左ローラ16の溝部の押し潰し面17、18が、リードフレーム基材11の幅方向両端部にそれぞれ形成されるエッジ高さhの0.3〜1倍(好ましくは、0.4〜0.8倍)程度食い込むように配置する。
即ち、リードフレーム基材11の幅をW(外側端部間距離)、右ローラ15及び左ローラ16の半径をr1、r2、右ローラ15及び左ローラ16の軸心距離(リードフレーム基材11の幅方向に対する)をdとすると、以下の式のようになる(なお、リードフレーム基材11の両端部のエッジ高さhは同じとしている)。
(W−2h)≦(d−r1−r2)≦(W−0.6h)
As shown in FIG. 2, the crushing surfaces 17 and 18 of the groove portions of the right roller 15 and the left roller 16 are formed at both ends in the width direction of the lead frame base material 11. It arrange | positions so that it may bite about 0.3 to 1 time (preferably 0.4 to 0.8 times) of the edge height h.
That is, the width of the lead frame base material 11 is W (distance between outer end portions), the radii of the right roller 15 and the left roller 16 are r1, r2, and the axial distance between the right roller 15 and the left roller 16 (lead frame base material 11). If d is (with respect to the width direction), the following equation is obtained (note that the edge height h at both ends of the lead frame substrate 11 is the same).
(W-2h) ≦ (d−r1−r2) ≦ (W−0.6h)

従って、本発明の一実施の形態に係るリードフレームの製造方法においては、レジスト膜が形成された薄板金属条材をエッチング液に浸漬して、所定のパターンを形成するエッチング処理が完了したリードフレーム基材11を、図1に示すようにこの装置10に通すことになるが、これによって、リードフレーム基材11の両端は押し潰されて平滑化し(端部処理)、その後の工程でこのエッジ部分が金属片として剥離しない。
なお、リードフレーム基材11はエッチング処理後、リジスト膜を剥離してもよいし、レジスト膜を剥離しないでそのまま付着した状態で処理を行ってもよい。
リードフレーム基材11の搬送は手動であってもよいし、自動送りしてもよい。自動送りの場合は、例えば、0.3〜5m/秒で送るのがよい。
Therefore, in the lead frame manufacturing method according to an embodiment of the present invention, the lead frame in which the thin plate metal strip on which the resist film is formed is immersed in an etching solution and the etching process for forming a predetermined pattern is completed. As shown in FIG. 1, the base material 11 is passed through the apparatus 10, whereby both ends of the lead frame base material 11 are crushed and smoothed (end processing), and this edge is used in the subsequent steps. The part does not peel off as a metal piece.
The lead frame substrate 11 may be peeled off the resist film after the etching process, or may be processed with the resist film attached as it is without peeling off.
The lead frame substrate 11 may be conveyed manually or automatically. In the case of automatic feeding, for example, the feeding is preferably performed at 0.3 to 5 m / second.

本発明は前記実施の形態の形状や寸法に限定されず、本発明の要旨を変更しない範囲での変更は本発明の技術的範囲となる。例えば、前記実施の形態においては、リードフレーム基材をローラコンベアによって搬送しているが、例えば、ベルトコンベアやチェーンコンベアによって搬送することもできる。
また、前記実施の形態においては、右ローラと左ローラの位置は固定であったが、例えば、弾性部材の一例であるバネ、ゴムやシリンダーによって右ローラと左ローラをリードフレーム基材に押しつけることもできる。この場合の加圧力は、リードフレーム基材が幅方向に座屈等の曲がり変形が生じない範囲で、かつエッジ部の40〜80%が押し潰される荷重とするのがよい。
The present invention is not limited to the shapes and dimensions of the above-described embodiments, and changes within a range that does not change the gist of the present invention are within the technical scope of the present invention. For example, in the above-described embodiment, the lead frame base material is transported by a roller conveyor, but may be transported by, for example, a belt conveyor or a chain conveyor.
In the above embodiment, the positions of the right roller and the left roller are fixed. For example, the right roller and the left roller are pressed against the lead frame substrate by a spring, rubber, or cylinder, which is an example of an elastic member. You can also. In this case, the applied pressure is preferably a load in which the lead frame base material is in a range in which bending deformation such as buckling does not occur in the width direction and 40 to 80% of the edge portion is crushed.

本発明の一実施の形態に係るリードフレームの製造方法を示す斜視図である。It is a perspective view which shows the manufacturing method of the lead frame which concerns on one embodiment of this invention. 同リードフレームを製造する装置の断面図である。It is sectional drawing of the apparatus which manufactures the same lead frame. (A)〜(D)は従来例に係るリードフレームの製造方法の説明図である。(A)-(D) are explanatory drawings of the manufacturing method of the lead frame which concerns on a prior art example.

符号の説明Explanation of symbols

10:装置、11:リードフレーム基材、12:ローラコンベア、13:押し潰しローラ群、14:小径の送りローラ、15:右ローラ、16:左ローラ、17、18:押し潰し面 10: device, 11: lead frame base material, 12: roller conveyor, 13: crushing roller group, 14: small diameter feed roller, 15: right roller, 16: left roller, 17, 18: crushing surface

Claims (3)

レジスト膜が形成された薄板金属条材をエッチング液に浸漬して所定のパターンを形成するリードフレームの製造方法において、
エッチング処理が完了したリードフレーム基材を、対向配置されたローラの間を通過させて、その幅方向端部を押し潰すことを特徴とするリードフレームの製造方法。
In the lead frame manufacturing method of forming a predetermined pattern by immersing a thin metal strip with a resist film formed in an etching solution,
A lead frame manufacturing method comprising: passing a lead frame base material having undergone an etching process between rollers arranged opposite to each other, and crushing an end in a width direction thereof.
請求項1記載のリードフレームの製造方法において、前記ローラは軸方向の両側にフランジ部を有する溝形ローラであって、前記リードフレーム基材を前記ローラの溝部に嵌入させて、前記リードフレーム基材の端部処理を行うことを特徴とするリードフレームの製造方法。 2. The lead frame manufacturing method according to claim 1, wherein the roller is a groove-shaped roller having flange portions on both sides in the axial direction, and the lead frame base material is fitted into the groove portion of the roller. A method for manufacturing a lead frame, comprising performing an end treatment of a material. 請求項1及び2のいずれか1項に記載のリードフレームの製造方法において、前記ローラは弾性部材又はシリンダーによって、前記リードフレーム基材の内側に付勢されていることを特徴とするリードフレームの製造方法。 3. The lead frame manufacturing method according to claim 1, wherein the roller is urged to the inside of the lead frame base material by an elastic member or a cylinder. 4. Production method.
JP2003376708A 2003-11-06 2003-11-06 Lead frame manufacturing method Expired - Fee Related JP4383828B2 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116646278A (en) * 2023-05-29 2023-08-25 天水华洋电子科技股份有限公司 Lead frame roll-type etching equipment

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116646278A (en) * 2023-05-29 2023-08-25 天水华洋电子科技股份有限公司 Lead frame roll-type etching equipment
CN116646278B (en) * 2023-05-29 2023-10-20 天水华洋电子科技股份有限公司 Lead frame roll-type etching equipment

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