KR100572896B1 - Apparatus for electro deflash using barrels in semiconductor package device and thereof method - Google Patents

Abstract

The present invention relates to an apparatus and method for deflashing a semiconductor package device using a barrel to remove flashes and resin bleeds generated in an epoxy compound molding process of the semiconductor package device. Loading a plurality of rotating barrel means; An electrolytic deflash step of causing the flash and the resin bleed of the semiconductor package device to be peeled off from the semiconductor package device; First washing the semiconductor package device with conventional washing water; Surface etching and neutralizing the immersed semiconductor package device in an acidic chemical agent; Second cleaning the semiconductor package device; And unloading the semiconductor package device in an electrolytic deflash apparatus.

Semiconductor Package Devices, Deflash, Resin Breed, Barrel

Description

Apparatus for electro deflash using barrels in semiconductor package device and description method}

1 is an assembly flowchart of a general semiconductor device;

2 is a deflash flow chart of a conventional semiconductor package device;

3 is an electrolytic deflash flow chart of a semiconductor package device according to the present invention;

4 is a front sectional view showing an electrolytic deflash reaction means of a semiconductor package device according to the present invention;

5 is a side cross-sectional view showing an electrolytic deflash reaction means of a semiconductor package device according to the present invention;

6 is a perspective view schematically showing a rotating barrel system employing a plurality of polygon barrels according to the present invention;

7 is a perspective view illustrating a polygon barrel according to the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic deflash apparatus for a semiconductor package element using a barrel and a method thereof in a deflash process of a semiconductor package element.

In more detail, water jet (or conventional water) is a semiconductor package device to remove flash and resin bleed (e.g., leaking of epoxy compound resin between the lead) which occurs during epoxy compound molding. Electrolytic deflashing device of semiconductor package device using barrel which peels flash and resin bleed from lead frame of semiconductor package device in all stages of step) It is about a method.

In general, as shown in FIG. 1, the semiconductor package device assembly process includes a die bonding attaching a silicon chip to a die pad of a lead frame (S10), and a wire bonding electrically connecting the silicon chip and a lead of the lead frame ( S20), epoxy compound molding to protect the silicon chip and wire from the external environment (S30), deflash (S40) to remove the flash and resin bleed flowing into the lead frame after epoxy compound molding, and the lead is oxidized Plating (S50) for plating a metal such as lead (SnPb) on the surface of the lead to prevent it, and screening (S70) and packaging (S80) for screening the electrical characteristics of the semiconductor package device (60) and identifying and commercializing the semiconductor package Proceeds in the order of.

On the other hand, the semiconductor package device is typically the epoxy compound in the epoxy compound molding (S30) is made of a flowable material by pressing the epoxy compound at a high temperature and high pressure, and then run the runner (tube that induces the epoxy compound to melt and flow into the mold mold) in the mold. In this case, the dam bar of the lead frame (supporting the lead in the lead frame) prevents the molding compound from flowing out of the lead frame. However, even when the dam bar is formed in the lead frame as described above, some of the molding compound flows out of the dam bar, and as the temperature of the molding compound decreases, it hardens on the surface of the lead frame, which is called flash and resin bleed. do. Since the lead generated with the flash and the resin bleed is not plated on the surface of the lead frame in the plating S50, the lead is injected into the deflash S40. Here, the de-flash S40 is usually performed after the epoxy compound molding S30 of the semiconductor package device is completed, and after the de-flash S40 is completed, the plating for plating a metal such as lead (SnPb) is performed. Proceeds to).

As shown in FIG. 2, the de-flash (S40) step includes a semiconductor chip mounted on a lead frame in the on-load (S100) step to wire bond, and molded with an epoxy compound to form a package body. In order to immerse a semiconductor package device in a pretreatment chemical, it is a preparatory step of packaging in a chemical preprocessing basket.

Chemical pretreatment immersion (S110) step is to immerse the semiconductor package device for 25 minutes in a solution of M-pyrrole C ₅ J ₉ NO (1- Methyl-2- Pyrrolidinone) at a temperature of about 120 ℃ and then take out (Rinse) In step S120, the semiconductor package is washed for about 10 minutes twice with a conventional cleaning solution. After the cleaning is completed in the off load (S130) step, the cleaned semiconductor package device moves out of the basket (S140) to be taken out of the basket and packed in a packing box to move to the waterjet step of the next step.

In the water jet step (S150), conventional water is strongly sprayed at a pressure of approximately 500 kgf / cm ^{2 on} the surface of the semiconductor package device, that is, the lead frame surface exposed to the outside of the package body, and thus the body of the semiconductor package device. Allow the flash and resin bleed formed on the and leads to be completely removed.

The above described deflash (S40) process has many problems. In the chemical pretreatment immersion step (S110), the lead frame of the semiconductor package device typically causes a change in the color of the epoxy compound itself or a contamination of the epoxy compound surface when it is immersed for a long time at a high temperature in a pretreatment chemical agent made of an organic material, and the epoxy compound surface The softening causes pores, pores, cracks, etc. on the surface of the epoxy compound molded by the pressure of the water when spraying strong water in the waterjet (S150) step, causing a fatal defect that exposes the chip or die pad mounted therein. Such defects caused defects in printing or unclear printing marks when printing a unique number for identifying a semiconductor package element in a post-process printing (S70) process. In addition, the chemicals used in the chemical pretreatment dipping step (S110) contain an excessive amount of organic substances for peeling off the epoxy compound from the lead, and the wastewater generated in the cleaning (S120) step of the semiconductor package device contains a large amount of organic components. In the wastewater treatment, the biological oxygen demand (BOD) and chemical oxygen demand (COD) are high, which makes it difficult to treat the wastewater, and thus, the cost increase and environmental problems exist.

Among the prior art similar to the present invention, there was a technique using electrolysis (not shown).

The chemical deflashing device and the deflashing-plating using the same include the steps of: introducing one side of the lead frame of the semiconductor chip package into the body containing the deflash solution along the conveyor belt while the one side of the lead frame of the semiconductor chip package is fixed to the conveyor belt; The current is supplied while the cathode is connected to the lead frame of the semiconductor chip package introduced into the deflash solution, so that hydrogen gas generated on the surface of the lead frame by electrolysis of water in the deflash solution causes the flash to be read. Lifting at the surface of the frame; And degassing the flash on the surface of the lead frame by spraying high pressure water onto the semiconductor chip package passing through the conductive plate.

The prior art described above is similar to the present invention only in that it is deflashed through electrolysis, and there is a big difference in object, construction, and effect from the present invention using barrel. The amount of deflash that can be made was small and there was a problem in that it was not possible to deflash various kinds of semiconductor package devices.

The present invention is to solve the conventional problems as described above to damage the semiconductor package device flash and resin bleed formed in the lead exposed to the outside of the semiconductor package device, that is, the outside of the package body after completion of the epoxy compound molding (S30) process Provides a device and method for deflashing semiconductor package devices using barrels that can remove flashes and resin bleeds without waste, and can be processed in large quantities. Can be implemented.

The chemical deflashing device and the deflashing-plating method using the same can handle up to 60 frames per minute, but the present invention can process up to 300 frames per minute by using a rotary barrel. By using a plurality of barrels, it is possible to electrolytically flush several kinds of semiconductor devices at the same time, and by rotating the barrels, the fluidity of the electrolytic de-flashing chemicals is made possible, the processing efficiency is increased, and the air aeration (using the air aeration It is possible to eliminate the need for a separate stirring device). Conventional barrels were used for plating, polishing, etc., but they were made of non-conducting materials (eg polyethylene, polypropylene, etc.), and inevitably used media for supplying the cathodes and products by installing a cathode inside the barrel. Since the barrel of the present invention is made of a material capable of directly energizing the barrel surface (eg, stainless steel, titanium, etc.), the barrel may be directly energized with the semiconductor package device, thereby eliminating the need for a separate media, and greatly increasing the uniform treatment effect and the energization efficiency. The plurality of polygonal barrels may forcibly rotate and slip the semiconductor package element mounted therein during rotation, thereby smoothly forming electrodes between the barrel surface and the semiconductor package element during rotation.

In order to achieve the above object, the electrolytic deflashing method of the semiconductor package device according to the present invention will be described in detail as shown in FIG.

 In the loading (S200) step, a plurality of semiconductor package devices in which a semiconductor chip is mounted on a lead frame, wire-bonded, molded with an epoxy compound, a package body is formed, and the semiconductor lead frame is cut to a predetermined size in a lot unit In individual barrels.

In the barrel (S210) step after the loading step, the inlet of the barrel is opened to put the semiconductor package element and the inlet is closed by fixing.

In the electrolytic de-flashing step (S220), the semiconductor package device is immersed in an alkaline electrolytic de-flash chemical having a temperature of about 40 ° C. or more, and at the same time, the barrel is rotated, and the semiconductor package device (lead frame) is immersed in the negative electrode plate 420 during immersion. It touches to have a negative electrode (the positive electrode plate and the negative electrode plate can change the electrode to be applied). The positive electrode current is applied to the positive electrode plate 530 covering the inside of the alkaline reaction part 600. Due to the rotation of the barrel, the lead frame loaded on the barrel surface energized from the rotating barrel center axis is energized to the lead frame while repeating contact and short circuit sequentially. At this time, the semiconductor package device, that is, the flash and the resin bleed exposed to the outside of the package body and fixed to the lead are separated at regular intervals by the gas generated on the surface of the lead frame as the electrolytic chemical is ionized.

The first rinse step (Rinse) step (S230), the washing the semiconductor device for about 2-3 minutes with conventional washing water.

Etching and neutralization step S240 is performed by immersing the semiconductor package device in an acidic solution to remove and neutralize the smut of the lead frame surface generated during the electrolytic deflash process.

The second rinse step (S250) finally cleans the semiconductor package device over about 5 minutes to clean the chemical components and contaminants remaining on the surface of the semiconductor package device.

The unloading step (S260) is a step of separating the semiconductor device in which the electrolytic deflash is completed from the electrolytic deflash apparatus in order to move to the waterjet step (S150) at a later stage.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIG. 4 so that those skilled in the art may easily implement the present invention.

As shown in FIG. 4, a silicon chip is mounted on a lead frame to bond the wire, and an epoxy compound is molded to form a semiconductor package element having a package body, which is loaded by the loading means 300 into the plurality of barrel means 310. .

The loaded semiconductor package element is contained in the barrel means, and the plurality of barrel means containing the semiconductor package element is moved to and immersed in the electrolytic deflash reaction means 330 by the vertical and horizontal movement means 380.

In the deflash reaction means, the barrel means is rotated by the barrel rotating means 320 to electrosplash the semiconductor package device so that the flash and the resin bleed are separated from the semiconductor package device.

The deflashed semiconductor package device is moved to the first cleaning means 340 by the up, down, left and right moving means 380 to be immersed, and the deflashed semiconductor package device is first washed with normal washing water.

The first cleaned semiconductor package device is moved to the etching and neutralizing means 350 by the vertical and horizontal movement means 380 and is immersed, and the washed semiconductor package device is etched and neutralized by immersing the acidic chemicals.

The etched and neutralized semiconductor package element is moved to the second washing means 360 by the up, down, left, and right moving means 380 to secondly wash the etched and neutralized semiconductor package element with a normal wash water.

The secondary cleaned semiconductor package element is moved to the unloading means 370 by the vertical and horizontal moving means 380 and the semiconductor package element is unloaded by the barrel means by the unloading means.

  According to the electrolytic deflashing device of the semiconductor package device according to the present invention as described above to remove the flash and resin bleed from the lead without chemical pretreatment immersion (S110) such as M-pyrrole to be completely removed in the waterjet (S150) step of the rear stage Can be. That is, the chemical pretreatment immersion step (S110) is characterized in that the electrolytic deflashing.

  As shown in FIG. 6, the electrolytic deflashing device of the semiconductor package device using the barrel manufactured to realize the above process electrochemically removes the flash and resin bleed of the epoxy compound formed on the lead frame of the semiconductor package device. First cleaning 340 means for cleaning the alkaline reaction portion 600, the alkaline auxiliary tank portion 610 of the electrolytic deflash reaction means 330, the electrolytic deflashed semiconductor package, and the first cleaning The acid reaction part 700 and the acid auxiliary tank part 710 of the etching and neutralization means 350 are left on the surface of the semiconductor package device to neutralize the semiconductor package device that has passed through the means while simultaneously removing the spots on the surface of the leadframe. The second cleaning means 360 for removing the chemical components and contaminants, and the lead frame and the polygon that can form the electrical contact by loading Constitutes a lowering and lateral moving or capable of vertical and lateral movement means 380 is rotated - the mozzarella barrel means 310 and rising to go to each step combines a plurality.

In the electrolytic deflashing device of the semiconductor package element using the barrel configured as described above, the barrel 310 means having a plurality of polygonal barrels coupled to each other by pressing the start button after the semiconductor package elements have been completely loaded into the individual barrels. After rising by 380, it is moved to the left and right to be moved to the electrolytic deflash reaction 330 means, and lowered and immersed in the electrolytic deflash reaction means. The immersed barrel means includes a negative electrode plate (the negative electrode may be applied to the negative electrode plate to the positive electrode plate) 420 installed at the center of the upper portion of the electrolytic dip overflow plate 415, and the electrode plate 410 attached to the barrel means. This is automatic grounding. At this time, the barrel is rotated by the barrel rotating means 320 and the power is automatically applied after about 5 seconds to proceed the electrolytic deflash process. As the alkaline electrolyte is decomposed by the current applied to each, gas (hydrogen gas when the anode is applied and oxygen gas when the anode is applied) is dissociated and dissociated from the electrode frame 410 of the barrel means in which the anode or cathode is formed. Hydrogen exfoliates the flash and resin bleed formed in the lead frame. The electrolytic deflashing is performed for a predetermined time, and after completion of the electrolytic deflashing, the barrel means is raised by the vertical and horizontal moving means again and stops for a predetermined time at the upper end of the electrolytic reaction means and buried in the barrel means. Recover electrolyte to reduce unnecessary chemical consumption. Thereafter, the process proceeds sequentially while moving to the first washing means 340, the etching and neutralizing means 350, and the second washing means 360 by the vertical and horizontal moving means (first and second orders). The cleaning means and the etching and neutralizing means do not apply current). After completion of the process, the barrel means returns to the initial position, which is the loading position, and ends with the operation end buzzer ringing.

Each reaction means applied to the above is composed of the electrolytic deflash reaction means 330, the first cleaning means 340, the etching and neutralizing means 350, the second cleaning means 360, The interior of the flash reaction means will be described in detail with reference to FIGS. 4 and 5.

A positive electrode plate 530 made of stainless steel or titanium, which is perforated to a predetermined size to induce electrolysis of the alkaline electrolyte (the negative electrode and the pole may be interchanged with each other) is installed. A negative electrode plate 420 that can be energized is provided (even if the positive electrode plate and the pole are interchangeable). In addition, the electrolytic de-flash reaction means for proceeding the electrolytic de-flash process is composed of an alkaline reaction unit 600 filled with alkaline electrolyte and an alkaline auxiliary tank 610 in which the alkaline electrolyte overflowed therefrom.

Outside the alkaline reaction unit, there is an overflow plate 415 for temporarily storing the overflowing alkaline electrolyte solution and sending it to the alkaline auxiliary tank unit, and the alkaline reaction unit and the alkaline auxiliary tank unit have electrolytes stored in the overflow plate. An inflow pipe 450 for supplying the alkaline reaction unit is in communication with the inlet pipe, and the alkaline electrolyte supplied with the pump 460 for supplying the alkaline electrolyte filled in the alkaline auxiliary tank unit to the alkaline reaction unit is supplied. The valve 470 that can adjust the amount of is installed. In addition, the discharge pipe 480 through which the overflowed alkaline electrolyte is discharged to the alkaline auxiliary tank part is completely peeled from the lead frame to remove suspended substances (eg, flash and resin bleed) included in the alkaline electrolyte. Is installed.

In addition, a heater 500 for heating the alkaline electrolyte is installed in the alkaline auxiliary tank unit, and the alkaline electrolyte temperature is automatically detected while the heater repeats the on-off by sensing the temperature of the alkaline electrolyte by the temperature sensor 510. The level sensor 520 is installed to maintain a constant and detect the amount of alkaline electrolyte.

In the first washing means and the second washing means, the washing water is a water sole valve (not shown) installed in the washing water inlet pipe when the barrel means starts to move to the first washing means after the completion of the electrolytic deflash in the alkaline electrolyte As it is opened, the washing water flows into the second washing means through the inlet pipe, overflows from the second washing means, and flows into the first washing means. The washing water overflowed from the first washing means is discharged to a wastewater treatment plant along a discharge pipe (not shown) for treatment. In addition, the water solenoid valve (not shown) is automatically shut off at the end of the operation so that unnecessary waste of washing water is not wasted when the equipment is not running.

The etching and neutralizing means is an apparatus for immersing the semiconductor package element in an acidic electrolyte after passing through the first cleaning means. The etching and neutralizing means includes an acid reaction part 700 and an acid auxiliary tank part 710. It is designed in the same structure as the deflash reaction means. (Except apparatus for applying electricity)

As shown in FIG. 7, the barrel means 310 of the electrolytic deflashing apparatus for a semiconductor package device using the barrel is made of a polygon using a perforated conductor. The water inlet is installed in the barrel means so that the treated water (the respective chemicals and the washing water) can penetrate through the perforated hole in the barrel surface and the semiconductor package device can be loaded (300) or unloaded (370).

In addition, an electrode plate connected to the barrel surface is attached to the barrel surface to act as a barrel support and to apply current to the lead frame by energizing a positive electrode or a negative electrode (a negative electrode plate touching the barrel means, but the positive electrode plates may be reversed with each other). Can be. Each barrel produced as described above is manufactured in a structure capable of mass production by installing a plurality of barrels with the top of a rotating shaft.

And a barrel rotating means 320 is installed at the upper end of the barrel system is connected to the gear coupled to the electrode plate on the barrel system rotation center axis is configured to rotate the entire barrel. At this time, the semiconductor package lead frame inside the barrel means is electrolytically flushed by contacting and short-circuit with the barrel surface by the rotation of the barrel rotating means.

As described above, although the present invention has been described with reference to the above embodiments, various modifications may be made without departing from the scope and spirit of the present invention.

Therefore, the electrolytic deflashing method of the semiconductor package device according to the present invention is a process of removing the flash and the resin bleed formed on the lead by being exposed to the outside of the semiconductor package device, that is, the outside of the package body. After immersed in alkaline electrolyte, it is electrolytically decomposed and the flash and resin bleed adhered to the lead is removed in a short time by utilizing hydrogen gas generated from the cathode or anode (in detail, the lead frame surface loaded and energized). It can be processed without damaging the semiconductor package device, it is possible to improve the productivity by shortening the working time and is characterized by the quality stability and ease of operation that can drastically reduce the defects generated during the waterjet treatment step after the present invention. In addition, it is an eco-friendly system that is easy to treat wastewater by using chemicals that do not contain organic substances.

Claims (14)

In the electrolytic deflash device of a semiconductor package element using a barrel, Loading means for mounting a semiconductor package element molded with an epoxy compound and having a package body to the barrel means; The semiconductor package element is contained therein and the surface is perforated to pass through the treated water. The semiconductor package element, which is rotated by the rotating motor at the upper end of the barrel rotating means and loaded inside the barrel, is forcibly rotated and is prevented from slipping into a polygon. A plurality of barrel means adapted to; Vertical and horizontal movement means for moving the barrel means up, down, left and right; Alkaline electrolyte is contained to carry out the electrolytic deflash process by immersing the barrel means moved by the up, down, left and right moving means, conducting the perforated surface to induce electrolysis of the alkaline electrolyte and penetrate each treated water. Electrolytic deflash reaction means using a sieve; First cleaning means containing washing water for cleaning the semiconductor package device that has undergone the electrolytic deflash reaction means; Etching and neutralizing means for neutralizing the semiconductor package device that has undergone the first cleaning means while simultaneously removing the spots on the surface of the leadframe; Second cleaning means for removing chemical components and contaminants remaining on the surface of the semiconductor package device through the etching and neutralizing means; Electrolytic deflashing apparatus of the semiconductor package element using a barrel consisting of the unloading means for taking out the second washed semiconductor package element from the barrel means. delete The method of claim 1, The surface of the barrel means combines a plurality of polygonal barrels with the rotation center axis as a vertex, and an electrode plate connected from the rotation center axis is attached to apply a current to the barrel support and the rotation to energize the cathode or the anode to the lead frame. An electrolytic deflashing device for a semiconductor package element using a barrel that is capable of electrolytic deflashing of different kinds of semiconductor package elements at the same time. delete The method of claim 1, The barrel means is connected to the gear coupled to the electrode plate on the central axis of rotation so that the entire barrel means can be rotated, the lead frame of the semiconductor package element is in contact with the barrel surface by the rotation of the barrel rotation means Electrolytic deflashing device of a semiconductor package element using a barrel, characterized in that the electrolytic deflashing while repeating the short-circuit operation. delete delete The method of claim 1, The electrolytic de-flash reaction means includes an alkaline reaction part filled with an alkaline electrolyte and capable of electrolytic deflashing using a cathode or an electrolytic deflashing using an anode by alternately alternating polarities of currents applied to the anode and cathode plates; A temperature sensor part containing the alkaline electrolyte overflowed from the alkaline reaction part, the heater part capable of heating the alkaline electrolyte solution, and the temperature sensor part maintaining a constant temperature of the alkaline electrolyte solution; An alkaline auxiliary tank unit including a level sensor unit capable of sensing an amount of the alkaline electrolyte; The electrolytic deflash reaction means includes: an overflow plate for temporarily storing the alkaline electrolyte overflowing from the alkaline reaction unit and outputting the alkaline electrolyte to the alkaline auxiliary tank unit; A filter disposed inside the overflow plate and installed at an end of the discharge pipe communicating with the overflow plate and the alkaline auxiliary tank to remove suspended substances contained in the alkaline electrolyte; An inlet pipe for sending an alkaline electrolyte from the alkaline auxiliary tank unit to the alkaline reaction unit; Located in the middle of the inlet pipe and the pump for supplying an alkaline electrolyte; Electrolytic deflashing device of a semiconductor package device using a barrel, characterized in that the valve is located between the pump and the alkaline reaction portion and between the pump and the alkaline auxiliary tank to adjust the amount of the alkaline electrolyte. delete delete delete The method of claim 1, The first washing means and the second washing means are introduced into the second washing means through the washing water inlet pipe while the water sole valve installed in the washing water inlet pipe is opened when the barrel means having finished the electrolytic deflashing process starts to move. And the washing water overflowed from the second washing means flows into the first washing means, The washing water overflowed from the first washing means is discharged to the wastewater treatment plant through a discharge pipe, and when the work of the second washing means is completed, the water brush valve is automatically shut off and the water brush is shut off. Electrolytic deflash device for semiconductor package device. delete A loading step of mounting a semiconductor package element molded with an epoxy compound and having a package body in a barrel means; A plurality of barrel steps containing the semiconductor package element and manufactured to allow the treated water to penetrate the surface thereof; An electrolytic deflash reaction step in which an alkaline electrolyte is contained in order to proceed with the electrolytic deflash process by immersing the barrel moved by the vertical and horizontal movement means; A first washing step containing washing water to wash the semiconductor package device that has undergone the electrolytic deflash reaction; Etching and neutralizing the semiconductor package device that has undergone the first cleaning step to neutralize at the same time as removing the spots on the surface of the leadframe; A second cleaning step for removing chemical components and contaminants remaining on the surface of the semiconductor package device subjected to the etching and neutralization steps; Electrolytic flash of the semiconductor package device using a barrel consisting of the unloading step of taking out the second washed semiconductor package device from the barrel step.

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