TWI237068B - Metal finishing apparatus and metal finishing method using the same - Google Patents

Abstract

A metal finishing apparatus and a metal finishing method using the same are provided. The metal finishing apparatus includes an electrolytic bath, an electrolyte contained in the electrolytic bath, a positive electrode dipped into the electrolyte, a negative electrode dipped into the electrolyte, and a membrane installed between the positive electrode and the negative electrode, and having fine pores to selectively permeate particular ions dissolved in the electrolyte during an electrode reaction from one electrode to another electrode.

Description

1237068 V. Description of the Invention Case No. (1) 91122241 Amendment [Fields related to the invention] The present invention is a metal finishing device, especially a membrane (membrane) capable of separating cathode and anode from each other, and the membrane is provided A metal finishing device in an "electrolytic bath" to avoid electrolytic precipitation of foreign matter on the electrodes and the use of another metal finishing method. [Previous description of technology] Generally speaking, semiconductor lead frames have different shapes depending on the high density and integration of semiconductor wafers and the way they are installed. Semiconductors are made of copper or iron alloys, and different types of impurities easily adhere to the surface of their raw materials.

^ Therefore, in order to obtain the desired shape of the semiconductor lead frame, it is necessary to use the engraving, stamping, and electrolytic polishing methods to remove the oxide from the surface of the material to increase its horizontal effect. of. When performing a wire bonding (write-bonding) process outside, it is also necessary to electrically connect a semiconductor lead frame having a different shape to a semiconductor wafer. Furthermore, the plating process is necessary to improve the bonding performance, corrosion resistance, and coating efficiency. Figure \ is an electrolytic polishing device 10 of a conventional metal finishing device.

As shown in FIG. 1, the electrolytic polishing device 10 includes an electrolytic cell, having an anode 12, a cathode 13, and a 5 'liquid 14 placed on the anode 12 and the cathode 13. The electrode 12 is a copper or iron alloy The fabricated semiconductor is made of metal, and the cathode 13 is a stainless steel (sus) or platinum plate. In addition, the electrolyte 14 is a water bath (aqueous sooiutiori) containing 60 ± "3.

Page 6 1237068

The leaning tank 16 communicates with the electrolytic tank 11 through a supply channel 7 and a return channel 8. A nozzle 9 capable of ejecting the electrolyte 丨 4 is arranged at the bottom of the electrolytic cell ^ ^. The conventional electrolytic polishing apparatus having the above structure has the following reaction modes. The oxidation reaction of Nippon Steel atoms that loses electrons and dissolves into copper ions occurs on anode 12, and the reduction reaction of copper ions receiving electrons to reduce to copper atoms occurs on cathode 13. However, the conventional metal finishing device has the following disadvantages: First, a sludge is formed in the electrolytic cell, and electrolytically precipitates on the surface of the anode 2 along the flow of the electrolytic solution 14. The coagulated precipitate that reacts between the metal ions decomposed by the anode 1 2 and the electrolytic solution 4 on the surface of the cathode 13 is an impurity containing a large amount of jj20 components. In addition, the precipitates on the product used as the anode 12 cannot be completely removed through the surface cleaning process, which leads to the inferiority of the product. Second, the precipitate deposited on the surface of the cathode 13 by electrolytic deposition will continue to increase until the cathode 13 is completely covered by the precipitate. As a result, the current (cu r r e n t) efficiency drops rapidly, reducing the speed of electropolishing. Therefore, in order to remove the sediment, the metal finishing device must regularly repeat the washing process, and the device must be stopped and driven temporarily. Especially in-line devices, such as semiconductor lead frames, must completely stop driving. Thirdly, the electrolyte solution 14 is deteriorated due to deposits, and the degree is reduced. Therefore, the solution must be filled at all times.

Fourth, the reaction byproducts (byproducts) generated from the anode are on the surface of the cathode, and a plating layer is formed during metal plating, which seriously affects the electrolytic layer and reduces the service life of the electrolyte. [Objective of the Invention] In order to solve the above problems, the main object of the present invention is to invent an improvement of a metal finishing device and a method for metal finishing using the same. The structure is provided with a thin film and its function is to selectively allow The specific ions penetrate from the two anodes to the one cathode, and the film is set in an electrolytic cell, and suppresses the generation reaction of foreign matter and prevents the electrolytic precipitation of the foreign matter on the electrode. /,

Another object of the present invention is to provide a metal finishing device and a metal finishing method using the same, which collect the specific ions of the electrolytic solution to deconcentrate the tank. [Solution] In order to achieve the first device mentioned above, it includes an electrolytic cell, an anode submerged in the electrolyte, and a thin film submerged between the anode and the cathode. It is decomposed in the electrode reaction by the electrolyte. To another electrode. The rabbit does not include a metal-refined electrolytic solution placed in an electrolytic cell, a cathode inserted into the electrolytic solution, and a device having many pores to selectively permeate special ions in it from an electrode. The second plate is a polished structure, and the cathode is-the surface of the metal anode. = = The electrode is decomposed from the anode by the electric polishing process to flatten the clothes, and the metal ions penetrate into the cathode to prevent metal precipitation. Products are generated on the surface of the cathode and cannot be separated

； 外 全 ::::: genus and the cathode system is-the junction of the acceptor bond ^^ is decomposed from the% electrode and the electrode surface is ^^, and 1237068 amended MM 9119.99 / 11 V. Description of the invention (4 ) The reaction brake product of the anode cannot penetrate into the negative metal ^ A metal finishing device because of the barrier of the thin film. The metal finishing device further includes an ion collection part, which can collect metal ions or reaction byproducts in the electrolytic solution on the side of the electrolysis h. A metal finishing method using a metal finishing device according to the present invention includes the following steps: & ^^^ An electrolytic cell having an anode and a cathode, both of which are immersed in an electrolyte W ^: Thin film, which has numerous pores to selectively allow specific ions to penetrate from one electrode to another: $: Electric current flows into the electrolytic cell to generate an electrode reaction, and 3 = # definite ions from one electrode can avoid penetration To other electric #; and, 子 7 ▲ Collects a specific ion holder generated in the electrode reaction by an ion collection part. The part is connected to one side of the electrolytic cell to maintain the electrolyte. Refer to 3 For the structural features, technical contents and functions of the invention, please send them to the writer; for the detailed description and drawings of the present invention, the attached diagram is for reference only, and is not intended to explain the drawing. ^ The figure is a schematic diagram of a conventional metal finishing device. The picture series is a creative metal finishing Luo Yi — The third picture series is based on the metal finishing package, its ^ yt "

^ Relation to time. X Figure 4 is a metal finishing device based on the second circle, and its Phosphoric acid concentration and time change. R Figure 4 is a metal finishing device based on Figure 2. 2 :: Figure. -A graph of the relationship between copper ion concentration and time change in the well. Mouth 1237068

Fig. 6 is a graph showing the relationship between the pollution value and the variation of the metal finishing device according to Fig. 2. [Details] FIG. 2 is a schematic diagram of a preferred embodiment of the electrolytic polishing device in the metal finishing device of the present invention. As shown in FIG. 2, the electrolytic polishing device 20 includes an electrolytic cell 21 having an anode therein. 22, a cathode 23 and an electrolyte 24 interposed between the anode 22 and the cathode 23. The anode 22 is a semiconductor lead frame, which is a polishing material made of copper or iron, and the cathode 23 is a stainless steel (Sus) or platinum grid. In addition, the electrolyte 24 is an acidic solution using a high current, and an aqueous solution containing 60 ± 5% H3P03 (-^ Q.uθ〇Us solution) / ^ 7 Fortunately, ^ []. In addition, a thin film 20 0 provided in the electrolytic cell 21 is used to avoid the precipitate formed by the reaction between the dissolved copper ions of the anode 2 2 and the electrolyte 24 on the surface of the cathode 23. Electrolytically deposited on the anode 22. The film 200 is located at a position where the anode 22 and the cathode 23 can be separated, and it is a thin layer of material like filter paper or gelatin (ce 1 1 u 1 oid). It has countless fine pores and selectively allows only specific ions to penetrate therethrough. Moreover, the film 200 The copper ion dissolved by the anode 22 is prevented from being electrolyzed on the cathode 23, and only thallium + ions are selectively penetrated through. A first storage tank 26 having a first pump 25 is disposed below the electrolytic tank 21. The first A storage tank 26 includes a first supply passage 27 and a first return passage 28 that communicate with the anode chamber 30 _ (_ positive electrode cell), and is used to supply and recover the electrolyte 24 in the anode chamber 30. The anode chamber 30 It is separated from the cathode chamber 40 by a thin film 200. Via the first supply

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Emperor 9112mi V. Description of the Invention (6) The emperor supplied by channel 27, X. 0, spouts from mouth 29. The% solution 24 can be connected through a spray provided at the bottom of the electrolytic cell 21-the second supply channel 2 70 and a third return channel 2 80, 220, 220, Λ tank, one to two, one to one The ion collector-secondary collector 220 of the third pump 260 supplies the copper ions in the electricity during the electrolytic polishing process, so that it is reduced to copper, thus avoiding copper 94η / person / has—the second pump 23 °, And the second storage channel 1 is connected to the first flow channel 2501 to connect the second storage tank 21o of the procedure for applying and recovering the electrolyte 24 from the cathode chamber 4o ^ to the electrolytic tank. Electrolysis: The solution 24 has the same composition, and is supplied to the anode chamber 30, and / or the electropolishing solution is collected in the second storage tank 2. * Pre: i t The electrolytic polishing device 20 of the present invention has the following reaction mechanism: Two, the anode 22 and the cathode 23 lose the rain electrons of copper atoms and decompose into lice, and the lice reaction occurs on the anode 22. At this time, the cathode ions are thin. However, the copper ions still decomposed by the anode 22 at Ξi cannot pass through, and the pores to the membrane move into the cathode chamber 40. Because of this, the copper ions precipitated from the thin film '-/ m' cannot be moved, but cannot be deposited on the surface of the cathode 23 because the copper ions and the second electrode 22 are separated. Therefore, avoid the generation of reactants in electrolysis and electrolysis of the precipitate in :::: precipitation. % Can be given on the anal surface

1237068 ------ Room number 91122ΑΠ 5. Description of the invention (7) The return channel 2 8 0 flows to the ion collection part 2 2 0 The concentration of copper ions in the electrolyte 24 can be avoided 2 8. The first storage tank 2 6th and 1st to collect copper ions. So avoid raising. One example = method can also be applied to borrow-suitable metal as anode and σ + V body lead frame plating structure as cathode for electroplating process in place of T, even if by-products of anode reaction are generated during electroplating, for anode The plating solution of the chamber and the cathode chamber can be controlled individually and independently. By setting a thin film between the anode and the cathode in the electrolytic cell, the plating by-products produced by the anode chamber cannot affect the cathode chamber. = The results of the application of the electrolytic polishing device 20 by the applicant of the present invention can be concluded as follows: For each container, the concentration of the electrolytic product in the container and the time schedule for the change between the copper deposits and the copper deposits. Table 1 Electrolyte precipitation in anode and cathode compartments of the cathode room] τ) W acid (%) copper (%) disc acid (%) copper (%) Shen Dian at the cathode 64. 3 益 64. 2 0 · 75 益 4 \\\ 64. 3 62. 3 1. 23 Yi 0, 64. 6 Yi 4 59. 7 1 · 71 62. 9 Yi 58. 7 2. 36 Μ is the gate—τ = shown in Table 1, the anode 22 is A semiconductor lead frame, and the cathode is made of non-recording steel (S Π S, a / solution 24 contains # 于) or a plate (Platinum grid) ° Furthermore, the electro-optical time gate K times ° In the electrolytic cell 2 1 supply 60 A / dm2 electric current 'and throw-, the length is 2 hours. This is used to avoid specific ions, such as

Case number

Internal anode 1237068 V. Description of the invention (8) The thin film 200 through which copper ions permeate is set between the electrolytic cell 2 j 22 and the cathode 23. 9 According to the results of the inspection, when the polishing process was performed for two hours, the phosphoric acid concentration in the anode chamber 30 changed from 64.2% to 62.3%, and 59.7 changed to ^ 58.7%. However, copper The ions change from 0.75 g / 1 to 1.7, change, in other words, with the passage of time, the "30 = 1" acid / Chen degree gradually decreases, and the copper ion concentration gradually increases. This is because the pole 22 The decomposed copper ions cannot penetrate through the thin film 200, and < ~ within the anode chamber 30. 远

_ on '— w The radon concentration from the main gate changed from 64.3% to A 64.W' from 64.6% to 62.9%, in other words, the change in the concentration of linoleic acid is also known as Membrane 2: Wider. There are copper ions present This means that copper ions cannot be changed from yang α to Shendian because of the blocking film 200. Shen Dian can not move on the surface of the cathode 23 to 40. Therefore, copper

Fig. 3 shows the axis of change in copper ion concentration and time representing time, and the γ axis represents copper ion 1 yang_middle 'X conversion. The connection B is the change of the copper ion concentration in the cathode chamber 40. As shown in the figure, the concentration gradually increases, and the copper ion concentration in the evanescent copper ion within the anode chamber 30 does not change. ": No 2: T facet" in the cathode chamber 40 ρ ions can not be moved to the messenger. The mouth is the second solution between the famous solution decomposed by the depolarizer 22, and the copper precipitate cannot be caused by the copper ions and ^ ^ ㈤ ^ formed on the surface of the cathode 23. Figure 4 shows the relationship between stone dance acid and time, γ car seven books, another inch of day, and double digitization, where X car Y glaze represents phosphoric acid concentration level

1237068 余 91 体 41 V. Description of the invention (9) The change in degree (9), the connection B is the change of phosphoric acid concentration in the cathode chamber 40. As shown in the figure, as time passes, the degree of anodicity gradually decreases. On the other hand, the phosphoric acid concentration within the range of ^ to 30 is the concentration of scale acid in the cathode chamber 40: In other words, the copper ion noise 撗 a * in the anode 22 does not change. low. The hafnium ion spread increases, and the phosphoric acid concentration decreases. Figure 5 shows the concentration of steel ions in the electrolytic cell 21 and the first storage tank 26. The line c represents the change in copper ion concentration in the electrolytic cell 21. Changes in copper ion concentration in a storage tank 26. ΛΙ), agricultural production ", the passage of time, the copper ions in the electrolytic cell 21 spread and gradually increase. On the other hand, the copper ions in the first storage tank 26 are doped: the copper ions in a storage tank 26 The reason for the decrease in concentration is that the copper ion is collected into the ion collection unit 220. The tenth and sixth graphs are the dirt maps in the first storage tank 26, where the X-axis represents time and the Y-axis represents pollution value 々 line binary value "The relationship diagram of the change in time. At this time, the intensity of the current supplied is: As shown in the figure, 'the pollution in the first storage tank ^ has a tendency to decrease' with the passage of time. This is because it is decomposed by the electrolytic tank 21 The ratio of the collected copper ions is relatively increased in the ion collection section 22. ^ As mentioned above, according to the metal finishing device of the present invention and the use of the metal ^ and production method, by providing a between the anode and the cathode Thin films and collection of specific ions can have the following advantages: First, the ions decomposed by the anode cannot be Jiang Xu

Page 14 1237068 91122241 V. Description of Invention (10) Formation. Furthermore, Shen Dianwu greatly reduced the rate of defective products.

The electrolysis of Shen Dian on the anode was avoided because of the second, because the precipitates had no fixed electric power, the third, the extension was possible, and the fourth, they could not be moved, but they were only used to cover the cover. The special flow rate was accurate. This is due to the electric length. Since the equality of the limited editions launched above Yin can be avoided first, the promotion is promoted. Xieye was born at the anode, the electric narrator, the hair. Mingshi changed 4 knives and Chen Ming. Electrolytic precipitation on the surface of the anode, called 丄 is relatively low compared to I1. As a result, the polishing speed can be maintained—reduced fugitive cleaning steps are reduced, production degradation is reduced, electrolyte replacement time, and the by-products of the anode reaction are effectively controlled during the battery process. It is only one preferred embodiment of the present invention, and the scope of implementation is only. That is, any modification according to the patent application scope of the present invention is included in the scope of the patent application for the invention

Page 15 1237068 _ Case No. 91122241 Simple description of the drawing Amendment [Simplified illustration of the picture] Figure 1 is a schematic diagram of a conventional metal finishing device. Fig. 2 is a schematic diagram of a preferred embodiment of a creative metal finishing device. Fig. 3 is a relationship diagram of copper ion concentration and time change according to the metal finishing device according to Fig. 2. Fig. 4 is a graph showing the relationship between the concentration of phosphoric acid (p h ○ s p h ○ r i c a c i d) and time according to the metal finishing device according to Fig. 2. Fig. 5 is a graph showing the relationship between the concentration of copper ions in an electrolytic cell and a storage tank and the time change according to the metal finishing device of Fig. 2.

Fig. 6 is a graph showing the relationship between the pollution value and the time change of the metal finishing device according to Fig. 2. [Main component symbol. Explanation]

1 0 electrolytic polishing device 11 electrolytic cell 1 2 anode 13 cathode 1 4 electrolyte 1 5 pump 16 storage tank 1 7 supply channel 1 8 return channel 1 9 nozzle 2 0 electrolytic polishing device 2 1 electrolytic cell 22 anode 23 cathode 2 4 Electrolyte 2 5 First pump 2 6 First storage tank 2 7 First supply channel 2 8 First return channel 2 9 Nozzle 3 0 Anode chamber 4 0 Cathode chamber 2 0 0 Thin film 2 1 0 Second tank

Case No. 91122241 1237068 on page 16 Brief description of the diagram 2 2 0 Ion collection section 240 Second supply channel 2 6 0 Third pump 2 8 0 Third return channel correction 2 3 0 Second pump 2 5 0 Second return Channel 2 7 0 Third supply channel

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Claims (1)

1 · A metal finishing device, mainly comprising: · an electrolytic cell; a valley electrolyte placed in the electrolytic cell; an anode submerged in the electrolyte; a cathode submerged in the electrolyte; and an anode and a cathode provided The thin film between them allows the electrode to decompose into the electrolyte ^^ in the reaction of the electrode selectively and permeate one electrode to the other electrode. ; And the metal ion or reaction by-product from the special ion 2_ As described in the metal patent application No. 丨, the anode system is a polished structure, and the cathode system is another, and the metal ion is provided by The electrolytic polishing process is flattened from the anode to the surface, and metal ions prevent the formation of metal deposits on the surface of the cathode by the anode and cathode of the thin film. &quot; 、, France penetrates into China, China and China. 3. The metal anode according to item 2 of the patent application scope is a lead frame. "H complete device, 4. The metal electrolyte described in item 2 of the scope of the patent application Λ electrolyte solution is an aqueous solution containing phosphoric acid as the main component: mobile device, and 5. The metal as described in item 1 of the scope of the patent application The anode system is a metal plate, while the cathode system is a two-or-thorium device. The metal ions are decomposed from the anode and electroplated to the danger: the structure of the plating; the reaction byproducts of the electrode cannot be blocked by the film; 6. Enter the cathode 1 h as described in item 5 of the scope of patent application. <It is a finishing facility, its case number is 1237068-. The case number is 2241 ^^ _ 6. The scope of patent application ~-In addition, it also includes an ion collection part, Tachimachi collects metal ions in the electrolyte of the electrolytic cell side Or respond to by-products. 7. The metal finishing device according to item 1 of the scope of the patent application, wherein the ion collection unit is connected to the first storage tank connected to the electrolytic cell, which supplies and recovers the electrolyte of the anode chamber, and the anode chamber It is separated from the cathode chamber through a thin film. 8. The metal finishing device according to item 6 of the scope of the patent application, wherein the ion collection unit is a first storage tank that is easily connected to the electrolytic cell, and supplies and recovers the electrolyte of the anode chamber, and the anode chamber It is separated from the cathode chamber through a thin film. 9. The metal finishing device according to item 7 in the scope of the patent application, wherein a second storage tank is connected to the other side of the electrolytic tank, which supplies and recovers the electrolyte to the cathode, and the cathode chamber is connected via a thin film. Separated from the anode compartment. 1 〇. # The metal finishing device described in item 8 of the scope of the patent application, whose snow A and storage are connected to the other side of the electrolytic cell, which supplies and recovers the cathode to the second liquid M〃, and the The cathode compartment is separated from the anode compartment via a thin film. • A metal finishing method, which mainly includes the following steps: The electrolysis of quasi-U t anode and cathode electrolysis, Cao's both submerged to selectively allow specific impurities;% u to the membrane, which has countless fine孔 Η 徂 ί penetrates from the electrode to another electrode; thunder; ^ ^ π I, ° current into the electrolytic cell to generate an electrode reaction, and; r specific ion decomposed by the electrode: and You-〇 by- Ion collection = two = internal; and specific ions, the ions are collected = wood mouth generated in the electrode reaction is connected to one side of the electrolytic cell to maintain electricity 1237068 _ Case No. 91122241 6. Scope of patent application Fixed concentration of solution. Correction Page 20