TW449819B - Semiconductor wafer cleaning system - Google Patents

Abstract

The present invention provides a semiconductor wafer cleaning system to remove the stain inked n the surface of the semiconductor wafer. The cleaning system comprises the first cleaning station, the second cleaning station and a drying station. The ink stain is dissolved by N-methyl-pyrolidone solution in the way of emerging and spinning in the first cleaning station. The surface of the wafer is washed by a cleaning solution in a spinning way in the second cleaning station after the processing of the first cleaning station. The wafer processed by the second cleaning station is blown dry to be matched with gas in a way of spinning dry in the drying station to remove the residual cleaning solution on the surface of the wafer.

Description

^ 4981 9 &5; Description of the Invention (υ Field of Inventioni) The present invention provides a cleaning system for semiconductor wafers, especially a cleaning system that uses I to remove ink breaks printed on the surface of a semiconductor wafer. Background In the integrated circuit (1C) industrial order, in order to enable the active device to properly perform the function of the intended design, ceramic or plastic is generally used on the outer layer of the integrated circuit I After encapsulation, the packaged wafers are sold to the market. Before the wafers are packaged, each electrical chip on the wafer must be tested for electrical functions to ensure the integrity of the factory 1C function. Because general wafer manufacturing plants and wafer packaging plants are carried out by different manufacturers or even in different regions, countries, and homes, the current semiconductor industry often uses ink _ printed on the surface of the wafer to mark wafers that have failed electrical tests. (Defective I die), in order to facilitate the subsequent packaging factory can clearly distinguish the electrical function test i: chips with good test results to avoid manufacturing It is a waste of packaging cost. At present, most of the operations in the industry to mark chips after electrical testing are performed by automated processes. The automated process uses a program built-in in a control unit to identify chips that do not meet electrical standards. And print it, so that the subsequent packaging | assembly factory can correctly screen defective wafers and eliminate them, to avoid packaging defective wafers and increase costs. However, sometimes it can be

Page 4 I. V. Description of the invention (2) It is possible that the machine is malfunctioning or there is a problem with the built-in program of the electrical test in the control unit. For example, there may be displacement or deviation of the print pins, which causes the mark data on each chip to be displaced accordingly. In this case, the correct information cannot be provided to the package manufacturer. In addition, because chip manufacturers may have different electrical functional requirements for each batch of products, the electrical standards that need to be entered in the preset program are different, and the printer station simply uses the character | No, so when the customer requests to change the electrical | standard, it is necessary to test and change the program one by one. At this time, the previous: mark must be removed and marked with the retest. 1! When the aforementioned problem occurs, there is an error in the printed mark on the wafer that needs to be added to 1 to remove it. Because there is no automatic equipment for this wafer cleaning process, the conventional method is to manually clean the wafer. The general cleaning method is that the operator uses acetone as the cleaning agent, and directly cleans the surface of the wafer with the | I hand brocade, and uses the dissolving power of acetone to the ink to remove the ink on the wafer surface. Collapse. This method of cleaning the surface of a person ____ cleans round surfaces, which not only requires a large number of cleaning agents to be constantly washed, but also consumes many human resources, which is very inconsistent with economic cost and efficiency considerations. In addition, acetone is a cleaning agent containing chemical component I, which may cause harm to human hands or other parts that come into contact with the cleaning agent, and will affect the health of the operator. On the other hand, because the amount of force and the position of the point of control during the wafer scrubbing process are not the same for everyone, it may cause the appearance quality of the wafer to be adversely affected, or even possible.

I | In the process of manual brushing, due to improper application of force, the inside of the wafer has been completed. The electrical function of the component is destroyed, which affects the yield of the process.

Page 5 449819-V. Description of Invention (3) i

I i i SUMMARY OF THE INVENTION Therefore, the main object of the present invention is to provide a cleaning system for semiconductor wafers, which is used to remove ink breaks printed on the surface of semiconductor wafers, so as to solve the problems of the conventional techniques. |!

In the embodiment provided by the present invention, the cleaning system includes a first I cleaning station, a second cleaning station, and a drying station. The first cleaning station utilizes an N-Methyi-Pyrolidone (NMP) solution to dissolve the ink on the wafer surface in an immersion and rotation manner. The second cleaning station uses a rotating method to rinse the surface of the wafer processed by the first cleaning station with a cleaning solution. The drying station uses a spin dry method and cooperates with a gas to blow dry the wafer processed by the second cleaning station to remove the residual cleaning liquid on the wafer surface. The cleaning system provided by the present invention uses an automated operation process to proceed: therefore, it can save human resources and reduce the consumption of cleaning agents, and does not easily affect the appearance of the wafer or the internal components of the wafer, which can ensure that Cleaning | \! 丨 The quality of the process. Detailed description of the invention Please refer to FIG. 1. FIG.

Page 6 449819 V. Description of the invention (4) Schematic diagram of ink collapse on a round surface. As shown in FIG. 1, the cleaning system 10 for removing ink rupture printed on the surface of a semiconductor wafer 18 according to the present invention includes a solution tank 12, a rotatable base 14 provided inside the solution tank 12, a The discharge hole 24 is provided at the bottom of the solution tank 12 and a supply nozzle 26 is used to supply various solutions required for cleaning the wafer 18. In the cleaning method of the present invention, first, a wafer 18 having an ink mark on the surface is horizontally placed on the base 14. The base 14 sucks the wafer 18 'in a vacuum i mode so that the wafer 18 can be fixed on the base 12 and rotated with the base 14. Then, the solution tank 12 is filled with N-Methyl-Pyrolidone (NMP) solution 16 and the entire wafer 18 is covered so that the wafer 18 can be immersed in the NMP solution 16. This step is mainly beneficial: the NMP solution 16 is used to dissolve the ink on the surface of the wafer 18. Then provide a power | rotate the base 14 in the direction of the arrow 20 on the base 14 and the solution tank 12 ', and: the NM P solution is rotated in the direction of the arrow 22 ", which is contained in the NM of the solution tank 12 The P solution | liquid 16 can increase the reaction area between the wafer 18 and the NMP solution 16 by flowing in a direction opposite to the direction of the base 14 and strengthen the dissolution rate of the NMP solution on the surface of the wafer 18. After a period of time, the circle 18 was cleaned by spin soaking, and then the NMP solution 16 in the solution tank 12 was drained through the drain hole 24. Or the susceptor 14 is designed as a device that can be raised, and the susceptor is used to raise the wafer to the original immersion; the NMP solution is above the liquid level 16 for the next cleaning step. Please refer to ^ 'FIG. 2 is a schematic diagram of rinsing the wafer surface by spin in the present invention. At this time, the susceptor 14 for carrying the wafer 18 continues to spin the spine in the direction of the arrow 20, and the spray nozzle-washing solution is sprayed from the supply nozzle 26 to rinse the above-mentioned 449819. V. Description of the invention ¢ 5)丨 the surface of the wafer. The cleaning solution can still be rinsed with fluorenone (NMP) solution or acetone (Acetone) solution. Next, DI water is sprayed onto the surface of the wafer 18 from the supply nozzle 26. In this step, I is mainly used to remove impurities or ink residues remaining on the surface of the wafer 18. I Please refer to Figure 3. Figure 3 is a schematic diagram of the wafer surface drying by spin-drying method of the present invention. In this step, the susceptor 14 for carrying the wafer 18 continues to rotate in the direction of the i arrow 20, and a dry air or an air is provided from the supply nozzle 26. That is, a spin dry method and a gas i are used to blow dry the cleaned wafer 18 to remove the residual cleaning solution or deionized water on the surface of the wafer 18 to ensure the drying of the wafer 18 In order to prevent water vapor from affecting the electrical properties of the I components in the wafer. At this time, the ink rupture on the surface of the wafer 18 has been completely removed.

I i Perform the electrical test again and mark it with a new mark. 1 In addition, the above-mentioned preferred embodiment of the present invention performs all steps in the same solution tank 12 to save equipment costs. However, in order to meet the requirements of different processes or equipment, three chemical stations can be set in the cleaning system, which can be used for different steps in different solution tanks using different supply nozzles. For example, the first cleaning station uses an immersion rotation method to dissolve ink collapse on the wafer surface with NMP solution. Then, the second cleaning station uses a rotation: rotation method to supply a cleaning solution with a supply nozzle to rinse the surface of the wafer processed by the first i cleaning station. Finally, the wafer is sent to a drying station. 丨 A spin-drying method is used, and a gas supply device is used to provide gas to blow dry the wafer processed by the second cleaning station to remove the remaining residue on the wafer surface.

笫 Page 8 ^ 4981 9; V. Description of the invention (6) 丨: Cleaning solution. This cleaning system can also achieve the same cleaning of semiconductor wafers |

; I 丨 washing effect.丨 I!

I

I I The semiconductor wafer cleaning system provided by the present invention mainly uses an automatic jr iization process to remove ink breaks printed on the wafer surface. It is known that the method of using a user to clean the wafer is relatively uneconomical and labor-intensive. In contrast, the system provided by the present invention can integrate all steps in a solution tank, and only needs to use the supply nozzle to provide different The washing solution is ready for each step. The cleaning solution in the solution i tank can be reused repeatedly or used to clean multiple wafers. Not only can I reduce the consumption of cleaning agents, but also save human resources. And the present invention; the main cleaning agent is mainly NMP falling liquid, compared with the conventionally used: acetone can remove the ink on the wafer surface, but the conventional method is limited by NMP ΐ: the solution is more than acetone May cause greater harm to the human body, can not be directly used by humans: the wafer is washed with NMP solution, and all _ steps of the present invention are automated processes 丨

I: There is no such concern when it is controlled, so a more effective NMP solution can be used for cleaning. In addition, in the present invention, the wafer is cleaned by steps such as immersion rotation, rinsing, spin-drying, etc., the water or gas that contacts the wafer surface, and the wafer is evenly rotated by the susceptor, so that the wafer is washed by the water or airflow The force is quite uniform, so it is not easy to affect the appearance of the wafer or the internal components of the wafer, which can ensure the quality of the cleaning process.丨 Compared with the conventional method for cleaning the ink on the surface of a semiconductor wafer, the present invention: The provided cleaning system is performed using an automated operation process, so it can: save human resources and reduce the consumption of cleaning agents, and it is not easy to cause wafer damage

Page 9 449819: V. Description of the invention σ) The appearance or the influence of the internal components of the wafer can ensure the quality of the cleaning process. The above is only the preferred embodiment of the present invention.

All equal changes and modifications made within the scope of the invention shall fall within the scope of the invention patent. 4 4 9 81-9 i Simple illustration of the diagram Simple illustration of the diagram | Figure 1 is a schematic diagram of dissolving ink on the wafer surface by immersion rotation in the present invention. i FIG. 2 is a schematic diagram of washing the wafer surface by spin in the present invention. Figure 3 is a schematic diagram of drying the wafer surface by a spin-drying method according to the present invention. Explanation of symbols in the diagram 10 Cleaning system 12 Solution tank 14 Base 16 NMP solution 18 Wafer 20 Rotation direction 22 Rotation direction 24 Drain hole 26 Supply nozzle

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Claims (1)

449819 6. Application for patent Fan Yuan 1. A cleaning system for semiconductor wafers (wafer), which is used to remove ink breaks on the surface of semiconductor wafers. The cleaning system includes: a first cleaning station, The first cleaning station uses an immersion rotation method to dissolve the ink on the wafer surface with N-Methyl-Pyrolidone (NMP) solution, and a cleaning solution surface; and a drying Station, and cooperate with a second cleaning station. The second cleaning station uses a rotating method to rinse the surface of the wafer processed by the first cleaning station. The drying station uses a spin dry (spin) dry) square gas to blow dry the wafer processed by the second cleaning station to remove the residual cleaning solution on the wafer surface. 2. If the first item of the scope of the patent application fails, the "first .._" system, wherein the first cleaning station includes a solution tank for containing the N-methylpyrrolidone (NMP) solution to soak the wafer And a pedestal for fixing and rotating the wafer. 3. For example, the cleaning system of claim 2 in which the N ~ fluorenyl ketone (NMP) solution contained in the solution tank flows in a direction opposite to the rotation direction of the first base to increase the wafer. Reaction area with lotion. 4. The cleaning system according to item 1 of the patent application scope, wherein the second cleaning station includes a second base for fixing and rotating the wafer, and a first supply device for spraying an N- Fluorenyl ketone (NMP) solution or acetone Page 12 449819 6. Apply for patent (Acetone) or deionized water (DI water) to remove the ink breakage remaining on the wafer surface. 5. The cleaning system according to item 1 of the patent application scope, wherein the drying station includes a third base for fixing and rotating the wafer, and a second supply device for supplying dry air or nitrogen to Remove the remaining cleaning solution on the wafer surface. 6. As described in the first patent application, the first and second cleaning stations and the drying station are the same cleaning device. The cleaning device further includes a fourth base for fixing and rotating the wafer. And a plurality of third supply devices for supplying the NMP lotion, the cleaning solution, and the gas, respectively. 7. A method for cleaning a semiconductor wafer, which is used to remove ink bursts printed on the semiconductor wafer. The cleaning method includes the following steps: fixing the wafer on a rotating base; soaking the crystal with NMP lotion Round; rinse the wafer with NMP detergent; spray-wash the wafer with deionized water; and blow the wafer with gas. 8. The cleaning method according to item 7 of the scope of patent application, wherein the rotating base carrying the wafer is set in a solution tank, and the solution tank contains a plurality of Page 13 449819 6. Scope of patent application The device should be used to supply NMP lotion, deionized water and the gas, and a drain hole to discharge the brewed NMP lotion or deionized water. 9. The cleaning method according to item 7 of the patent application scope, wherein the rotating base absorbs the wafer in a vacuum manner. 10. The cleaning method according to item 8 of the scope of patent application, wherein the gas is dry Page 14