Semiconductor cleaning equipment

Abstract

The invention provides semiconductor cleaning equipment which is characterized in that a dry cleaning cavity and a wet cleaning cavity are integrated in one cleaning equipment, a wafer transfer cavity is arranged, photoresist on a wafer is removed in the dry cleaning cavity through dry cleaning, and then the wafer transfer cavity is arranged in the wet cleaning cavity; and then the wafer transfer cavity is utilized to quickly transfer the wafer subjected to dry cleaning into the wet cleaning cavity for wet cleaning, so that the photoresist can be efficiently removed, the time interval between the dry cleaning process and the wet cleaning process of the wafer is improved, the cleaning efficiency and effect of the wafer are improved, and in addition, the wafer transfer cavity is utilized to quickly transfer the wafer subjected to dry cleaning into the wet cleaning cavity for wet cleaning. A mixed solution of sulfuric acid and hydrogen peroxide is used as a cleaning solution for wet cleaning, a rotating device and a spraying device are arranged in a wet cleaning cavity, and the rotating device is arranged to drive the wafer to rotate while the spraying device sprays the cleaning solution to the wafer, so that the cleaning solution is uniformly distributed on the wafer; and the wet cleaning effect is further improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to semiconductor cleaning equipment. Background Art

[0002] With the development of modern semiconductor technology, in large-scale integrated circuit manufacturing (LSI) and even very large-scale integrated circuit manufacturing (VLSI), the key dimensions of components produced are getting smaller and smaller, while the accumulated components are increasing. Removing the photomask (i.e., photoresist) after etching and continuous ion implantation is a very important and frequently performed step. Depending on the complexity of the front-end device manufacturing, the number of photolithography cycles ranges from 10 to 30 times. Each photolithography cycle requires a process to remove the photoresist without damaging the already made components, and requires excellent performance. Therefore, the repeated photoresist cleaning (PR-Strip) in the front-end component manufacturing process is particularly important in the wafer cleaning process.

[0003] At present, the cleaning of photoresist on the wafer usually first uses a dry cleaning device to dry clean the photoresist on the wafer, and then uses a wet cleaning device to wet clean the wafer after dry cleaning, so as to completely remove the photoresist on the wafer. However, since the existing cleaning equipment can usually only perform dry cleaning or wet cleaning, a long waiting time will occur during the transfer of the wafer between the dry cleaning equipment and the wet cleaning equipment, thereby increasing the difficulty of subsequent wet cleaning and affecting the effect of wet cleaning. In addition, the existing wet cleaning is usually to directly spray the cleaning liquid on the stationary wafer, and wet cleaning the wafer, which is easy to cause the cleaning liquid to be unable to be evenly dispersed on the surface of the wafer, thereby affecting the cleaning effect, and the existing cleaning liquid usually uses a mixture of ammonia and hydrogen peroxide, which cannot completely remove the photoresist on the wafer.

[0004] Therefore, there is an urgent need for a semiconductor cleaning device to improve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a semiconductor cleaning device for solving the problems of long transfer time between dry cleaning and wet cleaning and poor wet cleaning effect.

[0006] The present invention provides a semiconductor cleaning device, comprising:

[0007] A dry cleaning chamber, wherein the dry cleaning chamber removes the photoresist on the wafer by dry cleaning;

[0008] A wet cleaning chamber, wherein the wet cleaning chamber removes the photoresist on the wafer by wet cleaning;

[0009] A wafer transfer chamber, wherein the wafer transfer chamber is connected to the dry cleaning chamber and the wet cleaning chamber, so that the wafer can be transferred between different cleaning chambers through the wafer transfer chamber;

[0010] A rotating device and a spraying device are provided in the wet cleaning chamber. When the wafer transfer chamber places the wafer after dry cleaning on the rotating device, the spraying device sprays the cleaning liquid on the wafer. At the same time, the rotating device drives the wafer to rotate so that the cleaning liquid is evenly distributed on the wafer, so as to remove the photoresist on the wafer by cleaning with the cleaning liquid.

[0011] The cleaning solution is a mixture of sulfuric acid and hydrogen peroxide.

[0012] The beneficial effects of the present invention are as follows: by integrating a dry cleaning chamber and a wet cleaning chamber into one cleaning device, and providing a wafer transfer chamber, firstly, dry cleaning is used in the dry cleaning chamber to remove the photoresist on the wafer, and then the wafer transfer chamber is used to quickly transfer the dry-cleaned wafer to the wet cleaning chamber for wet cleaning, so that the photoresist can be efficiently removed, the time interval between the dry and wet cleaning processes of the wafer is improved, and the cleaning efficiency and effect of the wafer are improved. In addition, by using a mixed liquid of sulfuric acid and hydrogen peroxide as a cleaning liquid for wet cleaning, a rotating device and a spraying device are provided in the wet cleaning chamber, and while the spraying device sprays the cleaning liquid onto the wafer, a rotating device is provided to drive the wafer to rotate, so that the cleaning liquid is evenly distributed on the wafer, thereby improving the effect of wet cleaning.

[0013] Optionally, the cleaning liquid is a mixture of sulfuric acid and hydrogen peroxide, and the volume ratio of sulfuric acid to hydrogen peroxide in the cleaning liquid is 1:1 to 20:1. Its beneficial effect is that the main components of the photoresist are carbon, hydrogen and oxygen organic matter. When sulfuric acid and hydrogen peroxide are mixed in a volume ratio of 2:1, "Carro's acid" is generated. Carro's acid decomposes to form free radicals and reacts chemically with the photoresist to achieve the purpose of removing the photoresist. Compared with the existing cleaning liquid components and their ratios, the effect of wet cleaning can be improved, especially when the current dry cleaning is based on the oxygen plasma ashing principle, the use of sulfuric acid and hydrogen peroxide in a volume ratio of 2:1 as a cleaning liquid has a better cleaning effect and can completely remove the photoresist on the wafer.

[0014] Optionally, when the cleaning liquid is used to clean and remove the photoresist on the wafer, the temperature range of the cleaning liquid is 60 to 120 degrees Celsius. The beneficial effect is that when sulfuric acid and hydrogen peroxide with a volume ratio of 2:1 are used as the cleaning liquid, and the temperature range of the cleaning liquid is set to 60 to 120 degrees Celsius, the wet cleaning time is short and the cleaning effect is good.

[0015] Optionally, when spraying the cleaning liquid, the rotation speed of the rotating device is 10 to 1000 rpm. The beneficial effect is that when the rotating device rotates at a speed of 200 to 1000 rpm, the cleaning liquid sprayed by the spraying device on the wafer can be evenly covered on the wafer, thereby improving the efficiency and effect of wet cleaning.

[0016] Optionally, after the photoresist on the wafer is removed by the cleaning liquid, the spraying device sprays clean water onto the wafer, and the rotating device drives the wafer to rotate at the same time, so that the clean water is evenly distributed on the wafer, so as to remove the cleaning liquid on the wafer by the clean water. The beneficial effect is that after the photoresist on the wafer is removed by the cleaning liquid, the spraying device sprays clean water onto the wafer, and the rotating device drives the wafer to rotate at the same time, so that the clean water is evenly distributed on the wafer, thereby cleaning and removing the residual cleaning liquid and its reactants on the wafer, preventing the cleaning liquid from over-cleaning and preventing the reactants generated during cleaning from adhering to the wafer.

[0017] Optionally, the clean water is deionized water, and when spraying deionized water, the rotation speed of the rotating device is 800-1500rpm, and the time for removing the cleaning liquid on the wafer by cleaning with clean water is 1-5 minutes. The beneficial effect is that the cleaning liquid is cleaned with deionized water, and when cleaning with deionized water, the rotation speed of the rotating device is 800-1500rpm and the cleaning time is 1-5 minutes, which can completely clean and remove the residual cleaning liquid and its reactants on the wafer.

[0018] Optionally, after the cleaning liquid on the wafer is removed by washing with clean water, the rotating device drives the wafer to rotate to dry the wafer;

[0019] During drying, the rotation speed of the rotating device is 2000-3000 rpm. The beneficial effect is that after the cleaning liquid on the wafer is removed by washing with clean water, the rotating device continues to drive the wafer to rotate at a speed of 2000-3000 rpm, thereby drying the wet-cleaned wafer, which is convenient for subsequent processing of the dried wafer.

[0020] Optionally, the dry cleaning chamber utilizes the oxygen plasma ashing principle to decompose and oxidize the photoresist on the wafer in an environment of nitrogen and oxygen at a preset temperature, so as to remove the photoresist on the wafer by dry cleaning;

[0021] The wafer transfer chamber first places the wafer to be cleaned in the dry cleaning chamber for dry cleaning, and takes out the dry-cleaned wafer after the dry cleaning is completed; then places the dry-cleaned wafer in the wet cleaning chamber for wet cleaning, and retrieves the wet-cleaned wafer after the wet cleaning is completed. Its beneficial effect is that by setting up a dry cleaning chamber to remove the photoresist on the wafer using the oxygen plasma ashing principle, and then first placing the wafer to be cleaned in the dry cleaning chamber through the wafer transfer chamber for dry cleaning, and taking out the dry-cleaned wafer after the dry cleaning is completed; then placing the dry-cleaned wafer in the wet cleaning chamber for wet cleaning, and retrieving the wet-cleaned wafer after the wet cleaning is completed, the time interval between the dry and wet cleaning processes of the wafer is improved, and the cleaning efficiency and effect of the wafer are improved.

[0022] Optionally, a robotic arm is provided in the wafer transfer chamber, and the robotic arm is used to take and place wafers into different cleaning chambers to realize transfer and transmission of wafers between different cleaning chambers.

[0023] Optionally, the time for introducing the nitrogen into the dry cleaning chamber is 20 to 60 seconds, the gas flow rate of the nitrogen is 200 to 1000 sccm, the pressure in the dry cleaning chamber is 1 to 10 torr, and the preset temperature in the dry cleaning chamber ranges from 240 to 275 degrees Celsius. The beneficial effect is that the efficiency and effect of removing the photoresist on the wafer by dry cleaning is improved by setting the time and flow rate of introducing the nitrogen as well as the pressure and temperature in the dry cleaning chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the structure of a semiconductor cleaning device provided by an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of a wafer cleaning process in a semiconductor cleaning device provided in an embodiment of the present invention.

[0026] Numbers in the figure:

[0027] 1. Dry cleaning chamber; 2. Wet cleaning chamber; 3. Wafer transfer chamber; 4. Wafer loading area; 5. Wafer transfer area. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0029] like Figure 1 As shown, the present invention provides a semiconductor cleaning device, comprising: a dry cleaning chamber 1, a wet cleaning chamber 2, and a wafer transfer chamber 3 connected between the dry cleaning chamber 1 and the wet cleaning chamber 2;

[0030] Among them, the dry cleaning chamber 1 is provided with a nitrogen inlet, an oxygen inlet and a heater. The oxygen plasma ashing principle is used to decompose and oxidize the photoresist on the wafer in an environment of nitrogen and oxygen at a preset temperature, so as to remove the photoresist on the wafer by dry cleaning.

[0031] In some specific embodiments, the time for introducing the nitrogen gas into the dry cleaning chamber 1 is 20 to 60 seconds, the gas flow rate of the nitrogen gas is 200 to 1000 sccm, the pressure in the dry cleaning chamber 1 is 1 to 10 torr, and the preset temperature range in the dry cleaning chamber 1 is 240 to 275 degrees Celsius. The introduction of nitrogen gas first can improve the polymer residue on the side wall of the metal wire on the wafer, and then the introduction of oxygen can remove the photoresist on the wafer, thereby improving the effect of dry cleaning.

[0032] In this embodiment, a rotating device and a spraying device are provided in the wet cleaning chamber 2. When the wafer transfer chamber 3 places the wafer after dry cleaning on the rotating device, the spraying device sprays the cleaning liquid onto the wafer. At the same time, the rotating device drives the wafer to rotate so that the cleaning liquid is evenly distributed on the wafer, so as to remove the photoresist on the wafer by cleaning with the cleaning liquid; the cleaning liquid is a mixture of sulfuric acid and hydrogen peroxide.

[0033] In some specific embodiments, the cleaning solution is a mixture of sulfuric acid and hydrogen peroxide, and the volume ratio of sulfuric acid to hydrogen peroxide in the cleaning solution is 1:1 to 20:1. In some preferred embodiments, the volume ratio of sulfuric acid to hydrogen peroxide in the cleaning solution is 2:1.

[0034] In some specific embodiments, when the cleaning solution is used to clean and remove the photoresist on the wafer, the temperature of the cleaning solution is in the range of 60 to 120 degrees Celsius.

[0035] In some specific embodiments, when spraying the cleaning liquid, the rotation speed of the rotating device is 10-1000 rpm.

[0036] In this embodiment, a robotic arm is disposed in the wafer transfer chamber 3, and the robotic arm is used to take and place wafers into different cleaning chambers to realize the transfer of wafers between different cleaning chambers.

[0037] In this embodiment, the wafer transfer chamber 3 first places the wafer to be cleaned into the dry cleaning chamber 1 for dry cleaning, and takes out the dry-cleaned wafer after the dry cleaning is completed; then places the dry-cleaned wafer into the wet cleaning chamber 2 for wet cleaning, and retrieves the wet-cleaned wafer after the wet cleaning is completed.

[0038] In some embodiments, clean water is also provided in the wet cleaning chamber 2. After the cleaning liquid is used to clean and remove the photoresist on the wafer, the spraying device sprays the clean water onto the wafer. At the same time, the rotating device drives the wafer to rotate so that the clean water is evenly distributed on the wafer, so as to remove the cleaning liquid on the wafer through cleaning with clean water.

[0039] In some specific embodiments, the clean water is deionized water. When spraying deionized water, the rotation speed of the rotating device is 800-1500 rpm, and the time for removing the cleaning liquid on the wafer by cleaning with clean water is 1-5 minutes.

[0040] In some specific embodiments, after the cleaning liquid on the wafer is removed by washing with clean water, the rotating device drives the wafer to rotate to dry the wafer; during drying, the rotating speed of the rotating device is 2000-3000 rpm.

[0041] In some specific embodiments, Figure 1 As shown, the semiconductor cleaning equipment also includes a wafer loading area 4 and a wafer transfer area 5, wherein the wafer loading area 4 is used to store wafers, and the wafer transfer area 5 is arranged between the wafer loading area 4 and the wafer transfer chamber 3 to realize the transfer and transmission of wafers between the wafer loading area 4 and the wafer transfer chamber 3.

[0042] like Figure 1 As shown, the semiconductor cleaning equipment comprises a dry cleaning chamber 1, a wet cleaning chamber 2, a wafer transfer chamber 3, a wafer loading area 4 and a wafer transfer area 5. The whole process of cleaning the wafer in the semiconductor equipment is described below by way of example. Figure 2 As shown, the details are as follows:

[0043] S201, taking out a wafer to be cleaned from the wafer loading area 4 and putting it into the wafer transfer area 5, wherein the wafer to be cleaned has a photoresist to be removed.

[0044] S202, transferring the wafer to be cleaned from the wafer transfer area 5 to the wafer transfer chamber 3. For example, the wafer to be cleaned in the wafer transfer area 5 can be taken out by a robot arm in the wafer transfer chamber 3.

[0045] S203, transfer the wafer in the wafer transfer chamber 3 to the dry cleaning chamber 1, and use the oxygen plasma ashing principle to dry clean the wafer to remove the photoresist on the wafer. In the dry cleaning chamber 1, first adjust the temperature in the dry cleaning chamber 1 to 240 to 275 degrees Celsius through a heater, then introduce nitrogen into the dry cleaning chamber through a nitrogen inlet, and then introduce oxygen into the dry cleaning chamber 1 through an oxygen inlet, wherein the time for introducing nitrogen is 20 to 60 seconds, the gas flow rate of the nitrogen is 200 to 1000 sccm, and then introduce oxygen so that the pressure in the dry cleaning chamber 1 is 1 to 10 torr. Since the removal of the photoresist only requires the introduction of nitrogen and oxygen in a high temperature environment, the generated emissions are very friendly to the environment, reducing the use of electronic industrial-grade chemicals and achieving environmentally friendly production.

[0046] S204 , taking the wafer in the dry cleaning chamber 1 out to the wafer transfer chamber 3 . For example, the wafer in the dry cleaning chamber 1 may be taken out by a robotic arm in the wafer transfer chamber 3 .

[0047] S205, transferring the wafer in the wafer transfer chamber 3 to the wet cleaning chamber 2 for wet cleaning to remove the photoresist on the wafer. In the wet cleaning chamber 2, the nozzle of the spraying device first sprays a cleaning solution of sulfuric acid and hydrogen peroxide in a volume ratio of 2:1 onto the wafer, and at the same time, the rotating device drives the wafer to rotate at a speed of 200 to 1000 rpm, so that the cleaning solution is evenly distributed on the wafer, so as to remove the photoresist on the wafer by cleaning. In this process, the temperature range of the cleaning solution is 60 to 120 degrees Celsius. After the cleaning solution removes the photoresist on the wafer, the nozzle of the spraying device sprays deionized water onto the wafer again. At the same time, the rotating device drives the wafer to rotate at a speed of 800 to 1500 rpm, and the time for removing the cleaning solution on the wafer by cleaning with deionized water is 1 to 5 minutes. After the cleaning solution on the wafer is removed by cleaning with deionized water, the rotating device drives the wafer to rotate at a speed of 2000 to 3000 rpm to dry the wafer.

[0048] S206 , transferring the cleaned wafer to the wafer transfer chamber 3 . For example, the wafer in the wet cleaning chamber 2 can be taken out by a robotic arm in the wafer transfer chamber 3 .

[0049] S207 , transferring the cleaned wafer to the wafer transfer area 5 .

[0050] S208, transferring the cleaned wafers in the wafer transfer area 5 to the wafer loading area 4, completing the wafer cleaning process.

[0051] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A semiconductor cleaning device, characterized in that: include: A dry cleaning chamber, wherein the dry cleaning chamber removes the photoresist on the wafer by dry cleaning; A wet cleaning chamber, wherein the wet cleaning chamber removes the photoresist on the wafer by wet cleaning; A wafer transfer chamber, wherein the wafer transfer chamber is connected to the dry cleaning chamber and the wet cleaning chamber, so that the wafer can be transferred between different cleaning chambers through the wafer transfer chamber; A rotating device and a spraying device are provided in the wet cleaning chamber. When the wafer transfer chamber places the wafer after dry cleaning on the rotating device, the spraying device sprays cleaning liquid onto the wafer. At the same time, the rotating device drives the wafer to rotate so that the cleaning liquid is evenly distributed on the wafer, so as to remove the photoresist on the wafer by cleaning with the cleaning liquid.

2. The semiconductor cleaning equipment according to claim 1, characterized in that: The cleaning solution is a mixture of sulfuric acid and hydrogen peroxide, and the volume ratio of sulfuric acid to hydrogen peroxide in the cleaning solution is 1:1 to 20:

1.

3. The semiconductor cleaning equipment according to claim 1, characterized in that: When the cleaning liquid is used to clean and remove the photoresist on the wafer, the temperature range of the cleaning liquid is 60 to 120 degrees Celsius.

4. The semiconductor cleaning equipment according to claim 1, characterized in that: When spraying the cleaning liquid, the rotation speed of the rotating device is 10 to 1000 rpm.

5. The semiconductor cleaning equipment according to claim 1, characterized in that: After the cleaning liquid removes the photoresist on the wafer, the spraying device sprays clean water onto the wafer, and the rotating device drives the wafer to rotate so that the clean water is evenly distributed on the wafer, so as to remove the cleaning liquid on the wafer through cleaning with clean water.

6. The semiconductor cleaning equipment according to claim 5, characterized in that: The clean water is deionized water. When spraying the deionized water, the rotation speed of the rotating device is 800-1500 rpm, and the time for removing the cleaning liquid on the wafer by cleaning with clean water is 1-5 minutes.

7. The semiconductor cleaning equipment according to claim 5, characterized in that: After the cleaning liquid on the wafer is removed by washing with clean water, the rotating device drives the wafer to rotate to dry the wafer; During drying, the rotation speed of the rotating device is 2000-3000 rpm.

8. The semiconductor cleaning equipment according to any one of claims 1 to 7, characterized in that: The dry cleaning chamber uses the oxygen plasma ashing principle to decompose and oxidize the photoresist on the wafer in a nitrogen and oxygen environment at a preset temperature, so as to remove the photoresist on the wafer by dry cleaning; The wafer transfer chamber first places the wafer to be cleaned into the dry cleaning chamber for dry cleaning, and takes out the dry-cleaned wafer after the dry cleaning is completed; then places the dry-cleaned wafer into the wet cleaning chamber for wet cleaning, and takes back the wet-cleaned wafer after the wet cleaning is completed.

9. The semiconductor cleaning equipment according to claim 8, characterized in that: A robotic arm is arranged in the wafer transfer chamber, and the robotic arm is used to take and place wafers into different cleaning chambers, so as to realize the transfer and transmission of wafers between different cleaning chambers.

10. The semiconductor cleaning equipment according to claim 8, characterized in that: The nitrogen gas is introduced into the dry cleaning chamber for 20 to 60 seconds, the nitrogen gas flow rate is 200 to 1000 sccm, the pressure in the dry cleaning chamber is 1 to 10 torr, and the preset temperature range in the dry cleaning chamber is 240 to 275 degrees Celsius.

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