TWI236708B - Method and apparatus for filtering out metal chips from lift-off - Google Patents

Abstract

The present invention disclosed a method and apparatus for removing metal chips from lift-off of metal, comprising: a metal lift-off wet bench, dissolving the photo-resist by using organic solvent to lift-off the stencil layer of the metal; a magnetic metal removing tank for collecting the metal chips; a filter for filtering out the remaining photo-resist and non-magnetic metal chips; a pump for pumping the solvent through the filter and reclaiming the solvent; a DI water supply, supplying DI water to rinse the magnetic metal chips out of the tank; a waste solvent tank for storing the waste solvent; a new solvent tank for supplying new solvent; multiple of valves for controlling the flow of the solvent; a controller, controlling the overall operation.

Description

1236708 V. Description of the invention (1)-1 · 1 · FIELD OF THE INVENTION The present invention relates to a device and method for a semiconductor process, and particularly to stripping using a 1 if t-of f method Apparatus and method for removing metal fragments in solvent after removing metal pattern. 2 · Prior art The tearing method is a method of forming a pattern on a wafer in a semiconductor process, which is different from an etching method. The main purpose is to use photoresist to form a pattern that is opposite to the desired pattern. The metal film required for the pattern is then plated. The so-called hollow layer (Stenci 1 layer) on the photoresist pattern and no photoresist on the wafer. Immersed in the solution of the photoresist of the dissolving solution to tear off the metal on the hollow layer, and the remaining metal patterns on the wafer where there is no photoresist. This method is simpler than the etching method, eliminating the need for an etching process and saving time and labor. The removed metal fragments are discharged with the solvent, which is easy to pollute the environment. Generally, the solvent is recovered and reused, and the metal is usually filtered by filtration to recycle the solvent. Conventional device for removing photoresist and metal fragments 100 As shown in the prior art of FIG. 1, the photoresist and metal fragments removed from the wafer soaked in the photoresist tearing processing tank 10 are filtered through the filter 1 〇8 After filtering, return it to the processing tank 102. Switch 1 〇6 can be closed during immersion. After processing, turn on the switch 106 to allow the solvent to be pumped through the pipeline 1 0 4 to the filter 1 0 8 filter, but the filter 1 0 8 is easy to be blocked by metal fragments and needs to be replaced frequently, and the fine metal fragments can still pass the filter.

1236708 V. Description of the invention (2) The device 108 wears the pump. Another example is the application filed by the applicant of this case on October 4, 91. The Republic of China Patent Application No.

"Placement and method" refers to the method of using a filter to remove photoresist particles. However, for the photoresist with metal particles generated by the tearing method, the filter is easily blocked by metal fragments. If it is not completely removed, the pump is likely to wear And reduce service life. Among the methods for removing metals in sewage treatment technology are methods of using magnetic maggots to attract magnetic metals, so that the metal in the sewage passing through magnetic maggots is absorbed, and only water and solvents are discharged to remove magnetic metals. However, there is no equipment for semiconductor manufacturing. In the tearing process, 'metals such as chromium (Cr), gold / chromium (au / cr), Al / Cr composite layers, Al / Cu alloys / Cr, etc., some of which are ferromagnetic metals', require composite layer metals One layer is made of magnetic metal and can be held by magnetic poles. And the completely non-magnetic metal fragments can also be provided by the traditional filter screen. Therefore, a device that can remove the magnetic and non-magnetic metal fragments generated by the tearing method can be used to reduce the blocking of the filter screen and increase the use of the pump. life. 3. Summary of the Invention An object of the present invention is to provide a metal pattern tearing device for removing gold.

1236708 ~ — V. Description of the Invention (3) Fragmented Device 'to prevent metal fragments from flowing into the wastewater treatment tank to form pollution. A second object of the present invention is to provide a device for removing metal fragments by a metal pattern tearing device, so as to prevent the metal fragments from blocking the filter screen, thereby increasing the service life of the filter screen. Another object of the present invention is to provide a device for removing metal fragments from a metal pattern tearing device to prevent metal fragments from entering the pump to increase the service life. • 丨 Another object of the present invention is to provide a device for removing metal fragments from a metal pattern tearing device to recover precious metals. In order to achieve the above and other objects, a preferred embodiment of the present invention is to provide a metal pattern lift-off device to remove at least a package of metal fragments. 3-The metal pattern tear off processing tank is used to dissolve the photoresist. A stencil layer with a metal pattern torn off; a magnetic metal removal slot to attract magnetic metal debris with a magnetic reed; a metal debris collection slot to collect metal debris; a filter to filter the peeled photoresist and Non-magnetic Lu metal fragments; a pump that pumps the treatment fluid to a filter to recover the treatment fluid; a pure water supply source that supplies pure water that has been rinsed out of the magnetic metal to remove the magnetic metal in the tank; a waste liquid pool that has been invalidated for storage Used processing liquid; a new processing liquid storage tank 'for replenishing new processing liquid; a plurality of switches to control the processing liquid

Page 8 1256708 V. Description of the invention (4) — — — Flow direction; a controller that controls the operation of the entire device. Another preferred embodiment of the present invention provides a method for removing metal fragments by a metal pattern tearing device, which includes at least the following steps: (a) dissolving a photoresist with a treatment liquid to remove a metal hollow layer; (b) driving The pump causes the treatment liquid to flow through the magnetic metal removal tank to attract the magnetic metal by magnetic convection; (c) The treatment liquid is continuously circulated through the chestnut drive until the magnetic metal is completely removed by the reaction; (d) After the circulation is stopped, the magnetic metal is cut off Remove the magnetic force of the tank, and provide a set of pure water (DI water) to rinse and remove the magnetically attached metal material in the tank. The debris collection tank has been recovered and processed so far; (e) If the treatment solution is still effective, continue to continue. Then drain it into the waste liquid tank, and replenish the processing liquid from the new processing liquid storage tank. The other objects, features, and advantages of the present invention described above will make the present invention more comprehensible through the detailed description of the drawings < comparative illustrations. Resistance batch wet erosion resistance: slot 1 =: general ^ ^,, 202, 2 1 4, ^, 2)

I2367〇r V. Description of the invention (5) Open when removing the photoresist and metal, so that magnetic metal fragments are held in the magnetic metal removal groove 204 by the magnetic maggot. The magnetic coil of the magnetic metal removal slot 2 04 is also controlled by the controller 22 0 and should be kept constantly and closed only when metal fragments are removed. The solution for removing the magnetic metal is driven by the pump Π 〇 to keep the circulation state, and at the same time, the solution still having the non-magnetic metal and the photoresist is passed through the filter 8 to remove the non-magnetic metal and the photoresist. The solution is sent back to the photoresist tear-off processing tank 102 for recycling. After the metal removal process time is reached, turn off the power of the magnetic coil, and turn on the switches 205 and 208, so that pure water flushes the magnetic metal substance in the magnetic metal removal tank 204 to the collection tank 206. After the removal is completed, the magnetic metal treatment liquid will continue to circulate and wait for the next batch of goods to be processed. If the processing fluid has been used for a period of time or a certain wafer has been processed, it should be replaced with a new processing fluid. The solution after the transition can no longer be used. At this time, you can turn off the switch 2 丨 4 and stop the pumping action. Turn on the switch 2 0 2. 2 1 2 The waste liquid has been introduced into the waste liquid tank 2 1 8 by gravity. The processing liquid storage tank 1 is replenished with a new processing liquid, and the filter 1 08 may be a general filter screen, or may be, for example, the Republic of China Patent Application No. 0 9 1 1 2 2 93 9 filed by the applicant of this case. Replaceable multilayer filter. The controller 2 2 0 controls the operation of the entire device. FIG. 3 (A) is a top view of the magnetic metal removing groove 204 according to an embodiment of the present invention. Figure 3 (B) is a sectional view taken from the N pole to the full in Figure (A). The tank 302 is made of a material resistant to the erosion of the treatment liquid, and may be cylindrical, square, or other shapes' to facilitate the formation of the magnetic pole 304. The magnetic pole is excited by the coil 30 6. The upper part of the tank has an inlet for the metal treatment liquid. The upper part of the tank has a slope-shaped liquid disperser M?

Page 10 1236708 V. Description of the invention (6) ^ The treatment liquid 310 is guided to the periphery of the tank, so that the metal fragments 30 9 are indeed sucked by the n-pole and S-pole magnetic poles 3 0 4. However, this is not necessary. If the magnetic field 3 0 8 is strong enough, the liquid disperser 3 1 2 may be omitted. The treated liquid which has been separated and removed by the metal is recycled through the discharge port 3 1 8. The part of the removed metal substance after the adsorption is from the pure water supply source 2 1 9 The pure water flows into the inlet 3 1 4 and the pressure of the pure water is used to flush the adsorbed metal material down and then through the discharge port 3 1 9 Discharge to metal debris collection tank for recovery. FIG. 4 is a flowchart of an operation method of a metal debris removing device according to an embodiment of the present invention. The method of removing debris starts at step 402, the fiber is turned on and the cycle switch 2 0 2, 2 1 4 and the pump 1 10 are set. The process conditions are set. At step 404, the wafer is placed in the processing tank 1 〇 In 2, this tank can be a batch or single-chip processing tank. Immerse the wafer with the treatment solution to remove the photoresist and metal. If it is a single piece, inject the treatment solution and slowly rotate to remove the photoresist and metal. In step 406, a magnetic metal removal tank electrode power is provided to remove the magnetic metal. In step 408, filter the non-magnetic metal and photoresist with a filter. At step 4100, determine whether the process time has arrived. If not, return to step 4 06, continue to remove magnetic metals, filter non-magnetic metals and photoresist. If yes, go to step 4 1 2 and take out the wafer. Turn off the cycle switch and pump in step 4 1 4. At step 416, cut off the electrode power to the magnetic metal removal tank. In step 4 and 8, turn on the switches 2 0 8 and 2 5 and rinse the magnetic metal removing tank 2 0 4 with pure water from the pure water supply source 2 1 9 to discharge the metal fragments to the collecting tank 2 06. At step 4 2 0, it is judged whether the flushing time is up. If not, return to step 4 8 and continue to rinse the magnetic metal removal tank 204 with pure water to discharge metal fragments to the collection tank 206. If

1236708 — V. Description of the invention (7) Yes, judge whether the processing liquid usage time or the processing batch has arrived. If not, go back to step 402 and continue to operate another wafer. If yes, then in step 4 2 4 turn off the cycle switch 2 0 2, 2 1 4 and the pump to discharge the waste liquid to the waste liquid tank 2 1 8 and in step 4 2 6 from the new treatment liquid storage tank 1 0 1 New processing liquid, return to step 402, and continue to operate another wafer. Although the present invention has been disclosed in specific embodiments, those skilled in the art will understand that the form and details of this specific embodiment may be slightly changed, and modifications and changes made without departing from the spirit and concept of the present invention are The scope of the invention, the embodiments of the invention described above are for illustrative purposes only, and one is not intended to limit the scope of the attached patent application.

Page 12 1236708 Brief description of the drawings 5. Brief description of the drawings Figure 1 (prior art) Conventional device for removing photoresist and metal fragments. Fig. 2 is a block diagram of a device for removing metal fragments by a metal pattern tearing method according to an embodiment of the present invention. FIG. 3 (A) is a top view of a magnetic metal removing groove according to an embodiment of the present invention. FIG. 3 (B) is a sectional view taken from the N-pole to the S-pole in (A). FIG. 4 is a flowchart of an operation method of a metal debris removing device according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 100 Removal of photoresist and metal fragments 102 Photoresist tearing processing tank 106 Switch 110 Pump 200 Metal pattern removal method 2 2 2, 2 0 5, 2 0 8, 2 1 2, 2 1 4 2 04 Magnetic Metal removal tank 2 1 8 Waste liquid tank 2 2 0 Controller 3 04 Magnetic pole 3 0 8 Magnetic field device 104 Pipe 1 0 8 Filter metal debris device off 2 0 6 Metal debris collection tank 219 Pure water supply source 3 0 2 tank body 3 0 6 coil 310 processing fluid

123 ^ 708 Brief description of the diagram 312 Liquid disperser 314 Discharge cover 315 Discharge metal cover 316 Controller 317 Controller 318 Discharge V 319 Metal discharge port 40 2- 426 Steps

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Claims (1)

1236708 VI. Scope of patent application 5 • For the device in the scope of patent application item 1, the filter is a filter. 6 • The device according to item 1 of the scope of patent application, wherein the filter is a multi-layer filter screen that can be replaced. 7. The device according to item 1 of the scope of patent application, wherein the magnetic metal removal tank further comprises: a tank body made of a material resistant to the erosion of the treatment liquid; the draining officer has a switch, which is located at the bottom of the tank, and The controller shuts it down during maintenance to prevent metal fragments from falling into the processing liquid storage tank; a row of metal tubes has switches, which are opened by the controller during maintenance to allow metal fragments to fall into the metal debris collection tank; The liquid inlet is used to introduce the treatment liquid; a pure water inlet is used to introduce pure water when magnetic metals are washed; a liquid disperser is located on the top of the tank to form a slope, and the falling processing liquid is guided around the tank; A plurality of magnetic poles are excited by a coil to generate magnetic maggots to attract metal fragments, and are demagnetized during maintenance to collect metal fragments. 8 · If the device of claim 7 is declared, wherein the tank system is Page 16 丄 人 30 / 呢 六 '㈣Patent fan garden shape. ^ Earthquake position 10 in the scope of patent application of claim 7 'where the groove system has a square prism shape. For example, the device in the scope of patent application for item 7, wherein the slot system is more in which the N pole of the magnetic pole is rectified: for the device in scope 7, the twelve kinds of metal pattern tearing into t include less the following steps: The method of removing metal fragments, to) dissolve the photoresist with a treatment solution to tear the car > + α to remove the hollowed-out layer of the metal; hold the magnetic metal; and two magnetic metal removal grooves to magnetically suck the magnetic metal completely (c) The treatment liquid is removed by the reaction through the pump drive; after stopping the circulation with %% (d), the magnetic supply is completely cut off-the group of pure water (water) rushes to the magnetic force of the v groove f, and raises ^ s wa er; Jin, the magnetically attached metal substance in the light removal tank is recycled to the metal debris collection tank; (e) if the processing liquid is still effective, continue processing, if the processing liquid has been helmeted, 'then drain it into the waste liquid tank' The treatment tank is replenished with the treatment fluid. P.17