TWI244689B - Wafer dryers for semiconductor cleaning apparatuses - Google Patents

Abstract

A wafer dryer for use in a semiconductor cleaning apparatus includes an internal bath 210, an external bath 220, a solution supply line 250, a solution drain line, a pump 280, and drying means. The solution drain line has a first drain line 270 and a second drain line 260. A pump 280 for constantly maintaining a speed of a drained solution is installed on the first drain line 270. The drying means has an isopropyl alcohol (IPA) nozzle 310, a first gas spray nozzle 330 for spraying N2 gas, and a second spray nozzle 320. The second spray nozzle 320 is installed on all inner sidewalls of the external bath 220 and has a plurality of holes. Thus, no wave is produced at a surface of the drained solution.

Description

1244689 V. Description of the invention (i) [Technical field to which the invention belongs] The present invention relates to a cleaning device for a semiconductor process, and more particularly to a wafer dryer for a wafer after cleaning. [Prior Art] As far as the tendency of semiconductor elements to high accumulation is concerned, particles remaining on the surface of the wafer will seriously affect the characteristics of these elements. Therefore, the wafer cleaning process to remove particles on the wafer surface has recently become increasingly important in the semiconductor process. In order to uniformly clean the surface of the wafer without causing damage to it, generally wet cleaning techniques are mainly used. As wafer diameters increase and wafer sizes shrink, soaking systems using wet conditions are widely used. The cleaning device used for the wafer cleaning process includes a solution tank containing different solutions to clean the wafer in several steps. The cleaning process of the wafer is completed by passing through these solution tanks. The final step in the cleaning process is to dry the cleaned wafer, which is performed using a wafer dryer. FIG. 1 illustrates a conventional wafer dryer. Please refer to Fig. 1. The wafer dryer 100 includes an inner solution tank 10, an outer solution tank 20, a wafer guide 30, a direction adjustment valve 40, a dry object, and a solution supply line 50 and Solution drain line. The wafer dryer 100 is used for the final wafer cleaning and drying process. The dry object includes an isopropyl alcohol (IPA) nozzle 90 and a gas nozzle 80 that ejects nitrogen. The solution discharge pipeline includes a first discharge pipeline 60 and a second discharge pipeline 70, wherein the second discharge pipeline 70 can discharge the solution faster than the first discharge pipeline 60.

10553pi f.ptd Page 6 1244689 V. Description of the invention (2) 'One by one — The solution used to clean the wafer will be supplied from the solution supply line 50 to the inner solution tank 10' This solution supply line 50 has Valve 5 2 for adjusting solution supply. The solution overflowing from the inner solution tank will flow into the outer solution tank 200. The solution overflowing from the external solution tank 20 is sent out through the open bottom of the external solution tank 20. The wafer guide 30 in the internal solution tank can accept multiple wafers, so multiple wafers can be cleaned and dried at the same time. If a plurality of wafers are mounted on the circular guide rod 30 of the internal solution tank containing the solution, the particles remaining on the wafer will float on the surface of the internal solution ^ 10. These floating particles will mix with the solution and overflow into the external solution tank 20, and then be sent to the outside. After removing the particles with the solution overflowing to the outer solution tank 20, isopropyl alcohol (IPA) will be sprayed into the inner solution tank 10 from the IPA nozzle 90. The solution in the inner solution tank 10 where a layer of isopropyl alcohol film is formed will be slowly discharged through the first discharge pipe ^.阙 6 2 Chuan Anmeng right flute used to adjust the amount of discharge solution-The discharge pipe is edited. When the internal solution tanker's solution: slow; == k ', the particles on the wafer surface will be removed by deionized (D I) water and the surface tension of I p a. The deionized water on the surface of the wafer will be replaced by a 1.8 film and will be evaporated. At this time, the difference in surface tension between the IPA liquid film and deionized water can prevent particles from adhering to the wafer surface again, and can remove moisture from the wafer surface, which is called the " Maragani effect ( marangoni effect) " ° If the solution in the inner solution tank 10 runs to the bottom of the wafer through the first discharge pipe 60, the remaining solution can be quickly discharged through the second discharge pipe 70. The valve 72 for adjusting the amount of discharged solution is installed in the second discharge

1244689 V. Description of the invention (3) On pipeline 70. The diameter of the second discharge pipe 70 is larger than that of the first discharge pipe 60, so the solution discharge speed of the second discharge pipe 70 will be faster than that of the first discharge pipe 60. After the solution in the internal solution tank 10 has been completely discharged, heated nitrogen gas is sprayed from a gas nozzle 80 installed in the upper part of the internal solution tank 10 to dry the wafers. The gas nozzle 80 sprays heated nitrogen to dry the wafer in order to suppress the formation of an oxide layer on the wafer surface. In addition, during the entire process, the gas nozzle 80 will continuously inject nitrogen at normal temperature into the internal solution tank 10, so the surrounding oxygen will be removed to avoid the formation of an oxide layer on the wafer surface. Unfortunately, the above-mentioned wafer dryer has the following problems. First, the first and second discharge lines 60 and 70 both use gravity to discharge the solution, so the discharge rate will change with the amount of solution in the inner solution tank 10, that is, with the inner solution tank 10 The solution in the solution is discharged, and the discharge rate of the solution is slowed down. As a result, more time is needed to clean and dry the wafer, and the reliability of the wafer may be deteriorated. Secondly, when the gas nozzle 80 directly sprays nitrogen at a normal temperature on the surface of the solution in the internal solution tank 10, and when the solution is discharged through the first discharge pipe 60, a solution such as The wave shown in Figure 2. Therefore, the I PA liquid film formed on the surface of the deionized water will be broken, and it is difficult to remove the particles and dry the crystal circle by the Marangoni effect. [Summary of the Invention] In view of this, one object of the present invention is to provide a wafer dryer, which can maximize the horsepower by maintaining a fixed solution release rate.

10553pif.ptd Page 8 1244689 V. Description of the invention (4) Marangoni effect. Another object of the present invention is to provide a wafer dryer in which the discharged solution can maintain a smooth surface without wave. According to the above and other objects of the present invention, the present invention provides a wafer dryer applied to a semiconductor cleaning device, including an inner solution tank containing a solution, an outer solution tank containing a solution overflowing from the inner solution tank, and providing a solution. A solution supply line to the internal solution tank, a solution discharge line that discharges the solution from the internal solution tank when the wafer is dried, and a device is installed on the solution discharge line to maintain the discharged solution fixed A speed of pumps, as well as dry objects used to dry wafers. The wafer dryer further includes a directional adjustment valve, which is connected to the inner solution tank, and is used to select one of the solution supply line and the solution discharge line and open it to the inner solution tank. This solution supply line and solution discharge line are connected to a directional control valve. The solution discharge line includes a first discharge line and a second discharge line that discharges the solution contained in the internal solution tank faster than the first discharge line. The pump system is installed in the first discharge line. Valve systems for adjusting the amount of discharged solution are installed on the first and second discharge lines, respectively. The dry object includes an IPA nozzle installed on the internal solution tank and spraying isopropanol into the internal solution tank, a first nozzle installed on the internal solution tank and sprayed gas into the internal solution tank, and installed outside The entire inner wall of the solution tank is provided with a plurality of openings for injecting gas to a second nozzle of the outer solution tank. The wafer dryer further includes a speed conversion device for adjusting the

10553pi f. Ptd p. 9 Ϊ244689 'Explanation of invention (5) The rotation speed of the pump, by which water is removed. At the rate at which the solution is discharged. This solution is demystified, in order to make the above-mentioned objects, features, and advantages of the present invention more obvious and easy to say ^ such as ^ wenwen cite a preferred embodiment, and in conjunction with the accompanying drawings, will be described in detail [Embodiment] Figure f and Figure 4, wafer dry for semiconductor cleaning devices = including an internal solution tank 210, external solution tank 2 2 0, wafer guides, direction adjustment valve 2 4 0, solution supply tube Road 250, solution discharge line, pump 280, and dry items.

j The liquid holding supply line 2 50 supplies a solution for cleaning and drying the wafer to the internal solution tank 2 1 0. The solution in the inner solution tank 2 10 will overflow and then flow to the outer> valley tank 2 2 0. The overflowed solution is discharged to the outside through a drain line (not shown). A wafer guide 23 for receiving a plurality of wafers is installed in the internal solution tank 21.

When a plurality of wafers to be cleaned and dried are placed on the wafer guide 230, isopropyl alcohol is sprayed onto the surface of the solution in the inner solution tank 2 10 from the IpA nozzle 31 of one of the dried objects. on. This method uses the surface tension of ionized water and IPA. The solution in the inner solution tank 210 with the IPA liquid film is slowly discharged through the first discharge pipe 270. The valve 2 7 2 for adjusting the discharge amount of the solution is installed on the first discharge line 2 70. The pump 280, which is used to keep the discharge solution at a fixed speed, is installed on the first discharge pipe 270. Therefore, the present invention can maintain a constant solution discharge speed compared to the conventional method using gravity. In addition, it is used to adjust the rotation of the pump 280.

l〇553pi f. ptd page 10 1244689 V. Description of the invention (6) ^ / 2 2 0 in 2 10 can switch the discharge speed of the solution. When the maximum effect of the internal solution tank is slowly discharged, the Maragoni effect can be rounded. '' The solution to remove the particles on the wafer surface and the dry crystals to I is reliably removed through the first discharge line 270 and the second discharge total 9 β n °, the knife, the remaining in the inner solution tank 21 〇 The solution is drained by gravity, and then discharged quickly. The second discharge pipe 26 can open and bite the dual-use valve 2 6 2 is installed on the second discharge pipe 2 60. It is discharged after the drying process, and the solution in the night tank 21〇 The wafer is cleaned and the objects are dried. I = 1 This wafer is sprayed with gas for drying. In the above, you A, several gas nozzles 3 3 0 are installed in the internal solution tank 2 1 0 through the flute σ ”, and turbulent gas is sprayed to the internal solution tank 2 1 0 to dry the wafer. Until the body discharge pipe 27G discharge Out of this solution, the third-gas nozzle is only penetrated when the liquid in the tank passes through the first; the discharge line 2 7 0 discharges #, the nitrogen day at normal temperature mJ · # a rolling leg nozzle 32 and sprays to the outer solution Tank 22〇. This is to dry the oxygen in the device 200 to avoid the formation of an oxide layer on the wafer surface. According to the results, when the solution is discharged through the first discharge pipe 27, the solution is on the surface of the solution There will be no wave. Wafer dryer 200 has a directional adjustment valve 24, which is installed and connected to the lower part of inner solution tank 210. Solution supply line 25, first and second discharge pipes The circuits 2 7 0 and 2 6 0 are connected to the directional control valve 2 4 0. The directional control valve 2 4 0 is a three-way control valve which is designed so that when this valve is in a certain direction

10553pi f. Ptd Page 11 1244689 V. Description of the invention (7) When it is turned on, it will be closed in other directions, that is, the solution is supplied to the inner solution tank 2 through the 'valley / night supply line 2 5 0'. At 10, the part of the directional control valve 2 40 connected to the solution supply line 2 50 will be opened to allow the solution to flow through, and the directional control valve 2 40 is connected to the first and second discharge lines. 2 7 0, 2 6 0 will be closed. As illustrated in FIG. 4, the second gas nozzle 3 2 0 sprays nitrogen at a normal temperature to the outer solution tank 2 2 0 to remove the oxygen in the wafer dryer 2 0. The second gas nozzle 3 2 0 is installed on the four inner side walls of the outer solution tank 2 20 and has a plurality of openings 3 2 2 to spray gas to the outer solution tank 2 2 0. When the solution is discharged through the first-aid discharge pipe 270, the gas system is ejected to the external solution tank 2 2 0 through the second gas nozzle 3 2 0. Therefore, no waves are generated on the surface of the discharged solution. 'As a result, the damage of the I p A liquid film formed on the surface of the deionized water can be avoided.' The particles on the wafer surface can be removed more stably, and the crystal circle. ~ Wafer dryer 400 series without directional control valve (shown in Figure 3) is shown in Figure 5. Referring to Fig. 5, the solution supply line 4 40, the first discharge line 4 60, and the second discharge line 4 50 are independently connected to the inner solution tank 4 1 0. The flow of the solution is adjusted by the valves 442, 462, and 45 2 installed on the solution supply line 440, the first discharge line 460, and the second discharge line 460. This wafer dryer 400 has the same composition as that of FIG. 3, so further detailed description is omitted. In short, by installing a pump on the solution discharge pipeline, the discharge solution can be maintained at a fixed speed, and the speed of the solution discharge can be adjusted. As a result, the time required to dry the wafer can be shortened, and the optimal drying time can be met.

〇553pi f. ptd Page 12 1244689 V. Description of the invention (8) Drying process conditions to improve quality, and to clean and dry wafers. Furthermore, when the solution is discharged, nitrogen is not sprayed directly on the solution surface, and no wave is generated on the solution surface, so a stable environment can be realized for the cleaning and drying process. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make various changes and decorations without departing from the spirit and scope of the present invention. The scope of protection of the invention shall be determined by the scope of the attached patent application.

10553pif.ptd Page 13 1244689 Brief description of the drawings [Simplified description of the drawings] Figure 1 shows a conventional wafer dryer; Figure 2 shows the problems that occur when the solution in the internal solution tank has waves; FIG. 3 shows a wafer drying according to a preferred embodiment of the present invention. FIG. 4 shows a top view of the wafer dryer of FIG. 3; and FIG. 5 shows a comparison of the wafer dryer according to the present invention. A schematic diagram of a modified example of the wafer dryer of the preferred embodiment. [Illustration of standard diagrams] 1 0 0, 2 0 0, 4 0 0 Wafer dryer 1 0, 2 1 0, 4 1 0 Inner solution tank 2 0, 2 2 0 Outer solution tank 3 0, 2 3 0 Wafer guide 40, 2 4 0 Directional adjustment valve 90, 310 IPA nozzle 80, 320, 330 Gas nozzle 280 Pump 60, 270, 460 First discharge line 290 Speed conversion device 70, 260, 450 Second discharge pipe Line 5 0, 2 5 0, 4 4 0 Solution supply lines 52, 62, 72, 252, 262, 272, 442, 452, 462 Valve 3 2 2 Opening

10553pif. Ptd Page 14

Claims (1)

1244689 6. Scope of patent application 1. A wafer dryer for a cleaning device for a semiconductor process, comprising: an inner solution tank for holding a solution, and a wafer system to be cleaned and dried is placed in the solution An outer solution tank for receiving the solution flowing out of the inner solution tank; a solution supply pipeline for supplying the solution to the inner solution tank; a solution discharge pipeline for drying the wafer At the same time, drain the solution from the inner solution tank; a pump to maintain the discharged solution at a fixed speed, the pump system is installed on the solution discharge pipeline; and a drying object to dry the crystal circle. 2. The wafer dryer described in item 1 of the scope of the patent application, further comprising a wafer guide bar installed in the inner solution tank to receive a plurality of wafers. 3. The wafer dryer described in item 1 of the scope of patent application, further comprising a directional adjustment valve, which is installed to be connected with the inner solution tank, and determines the solution supply pipeline and the solution discharge pipe One of the paths is to open the inner solution tank, wherein the solution supply line and the solution discharge line are connected to the direction adjustment valve. 4. The wafer dryer according to item 3 of the scope of the patent application, wherein the solution discharge pipeline includes: a first discharge pipeline; and a second discharge pipeline for the solution in the inner solution tank. The solution is discharged at a faster rate than the first discharge line, 10553pi f. Ptd Page 15 1244689 6. Scope of patent application Where the pump system is installed on the first discharge pipe. 5. The wafer dryer as described in item 4 of the scope of patent application, further comprising a first valve installed on the first discharge pipe to adjust the amount of the discharge solution. 6. The wafer dryer according to item 4 of the scope of patent application, further comprising a second valve, which is installed on the second discharge pipeline to adjust the amount of the discharge solution. In the wafer dryer, the drying objects include: an I PA nozzle installed on the inner solution tank to spray isopropyl alcohol to a middle portion of the inner solution tank; a first nozzle installed on the inner solution tank; A gas is sprayed onto the inner solution tank, and a second nozzle is installed on the entire inner side wall of the outer solution tank. The second nozzle has a plurality of openings for spraying. A gas is discharged to the external solution tank. 8. The wafer dryer according to item 7 of the scope of patent application, wherein the gas is nitrogen. 9. The wafer dryer according to item 3 of the scope of patent application, further comprising a speed conversion device for adjusting a speed of the pump to convert a speed of the discharged solution. 10. The wafer dryer according to item 1 of the scope of patent application, wherein the solution is deionized water. 10553pif.ptd Page 16