TW201800184A - Supply system and method for providing polishing liquids - Google Patents

Abstract

This invention provides a supply system and a method for providing polishing liquids. The supply system comprises at least one water supplying apparatus and a polishing liquid supplying apparatus. The water supplying apparatus and the polishing liquid supplying apparatus are respectively connected with at least one first container and at least one second container. At least the first container and at least the second container are respectively connected with at least one polishing machine. A prior polishing machine has a big volume, and its manufacturing cost is too high and it is not convenient to use a prior polishing machine.

Description

Polishing liquid supply system and method

The invention relates to a polishing liquid supply system and method, in particular to a semiconductor silicon wafer polishing liquid supply system and method.

The traditional semiconductor wafer polishing liquid supply system is Central Supply. As shown in FIG. 1, the conventional semiconductor silicon wafer polishing liquid supply system includes at least one central pure water supply device 1, and the pure water supply device 1 and the polishing liquid stock tank 3 are connected to at least one first central liquid storage tank 21. And at least one second central liquid storage tank 22, the first central liquid storage tank 21 and the second central liquid storage tank 22 are connected to at least one local liquid storage tank 4, and the local liquid storage tank 4 is connected to at least One polishing machine 5.

Specifically, in the conventional semiconductor wafer polishing liquid supply system, two central storage tanks (generally one for one use and one for backup) are set in the central supply system, and the polishing liquid stock solution is driven from the stock tank to the central storage tank, and the deionized water is purified by pure The water supply system hits the central storage tank. The polishing liquid stock solution and deionized water are mixed at a fixed ratio in the central storage tank. After a series of parameter tests (such as pH value and specific gravity), the mixed polishing liquid is supplied to the pump. The local liquid storage tank next to each polishing machine is then supplied to the polishing machine for polishing operations by the local liquid storage tank.

However, this traditional polishing liquid supply system has the following problems: it is necessary to set up a central supply system and a local liquid storage tank at the same time, which takes up space; The polishing liquid is generally a strong alkaline solution. Pumps and pipelines in the supply process need to use corrosion-resistant materials, and the supply of the polishing liquid is mixed with pure water in a low proportion. The supply is large, which makes the cost of the pump and pipeline in the central supply system relatively high. high.

The mixing ratio of the polishing liquid supplied by the central system is fixed, so that the polishing liquid mixing ratio of each polishing machine cannot be different, which is inconvenient when performing experiments for optimization.

In view of the shortcomings of the prior art described above, an object of the present invention is to provide a polishing liquid supply system for solving the problems that the polishing liquid supply system in the prior art has a large space occupation, a high production cost, and inconvenient use.

To achieve the above and other related objectives, the present invention provides a polishing liquid supply system, the polishing liquid supply system includes: at least one pure water supply device and at least one raw liquid supply device, the pure water supply device and the raw liquid supply The device is connected to at least one first liquid storage device and at least one second liquid storage device, and the first liquid storage device and the second liquid storage device are connected to at least one polishing machine.

Preferably, the pure water supply device and the original liquid supply device are connected to at least one liquid storage device group, and each of the liquid storage device groups includes a first liquid storage device and a second liquid storage device, and each storage device The liquid device group is connected to a polishing machine.

Preferably, the first liquid storage device and the second liquid storage device are provided with a first liquid level, a second liquid level, a third liquid level, a fourth liquid level, and a fifth liquid level which are sequentially lowered in liquid level. The liquid level is provided with a liquid level sensor.

Preferably, during the filling process, the liquid level sensor of the fifth liquid level is triggered, and the pure water supply device is supplemented with deionized water; the liquid level sensor of the fourth liquid level is triggered, and pure water is supplied. The device should be supplemented with deionized water; the third level liquid level sensor is triggered, the pure water supply device stops replenishing the deionized water, and the liquid storage device starts to replenish the polishing liquid; the second level liquid level sensor The detector is triggered, the liquid storage device stops replenishing the polishing liquid; the liquid level sensor of the first liquid level is triggered, the liquid storage device stops replenishing the polishing liquid, the liquid filling system is closed, and an alarm is given.

Preferably, during the liquid supply process, the liquid level sensor of the first liquid level is triggered, the liquid storage device stops liquid supply, the liquid supply system is shut down and an alarm is given; the liquid level sensor of the second liquid level Will not be triggered; the liquid level sensor of the third liquid level will not be triggered; the liquid level sensor of the fourth liquid level is triggered, and the liquid storage device of the liquid level sensor is triggered The liquid supply is stopped while another liquid storage device starts to supply liquid; the liquid level sensor of the fifth liquid level is triggered, the liquid storage device stops liquid supply, the liquid supply system is shut down and an alarm is given.

Preferably, the polishing liquid in the liquid storage device is a silicon wafer edge, and a polishing liquid used for polishing the front and back surfaces of the silicon wafer.

Preferably, it further comprises one or more combinations of a temperature control device and a stirring device provided in the liquid storage device.

Preferably, it further comprises one or more combinations of a circulation device and a filtering device connected to the liquid storage device.

The invention also provides a polishing liquid supply method. The polishing liquid supply method includes: step S1: receiving a liquid supply signal, the first liquid storage device starts liquid supply; step S2: judging whether the first liquid storage device has completed the liquid supply, If yes, go to step S3; if no, continue to step S2; step S3: the first liquid storage device stops liquid supply, the second liquid storage device starts liquid supply, and the first liquid storage device starts liquid filling; step S4: determine the second Whether the liquid supply of the liquid storage device is completed, if yes, go to step S5; if not, continue to step S4; Step S5: the second liquid storage device stops liquid supply, and the first liquid storage device Liquid supply was started, and the second liquid storage device began to be filled.

Preferably, the liquid filling includes the following steps: Step S01: adding deionized water to the liquid level in the liquid storage device, stopping replenishing the deionized water and recording the replenishing amount of the deionizing water; step S02: following the preset polishing liquid Proportion to deionized water, determine the supplemental amount of polishing liquid and the polishing liquid according to the supplemented amount of deionized water; step S03: online check whether the specification of the polishing solution in the liquid storage device reaches the preset specification of the polishing solution, and if so, Continue to step S03, if not, go to step S04; Step S04: alarm prompt.

Preferably, the supplemented amount of the deionized water is recorded using a pure water flow meter, and the supplemented amount of the polishing solution is recorded using an integrated flow meter.

Preferably, the setting parameters of the polishing liquid specification include one or more combinations of temperature, pH value and particle content.

As mentioned above, the polishing liquid supply system and method of the present invention have the following beneficial effects:

(1) There is no need to set a central supply system, which is conducive to reducing the space occupied by the polishing liquid supply system, and reduces the cost of pumps and pipelines in the polishing liquid supply system.

(2) The polishing liquid mixing ratio of different polishing machines can be different, which is more convenient when doing experiments to optimize, and is conducive to improving polishing quality.

(3) The automatic liquid filling and liquid supply of the first liquid storage tank and the second liquid storage tank are realized, which is beneficial to improving production efficiency.

1‧‧‧ Central Pure Water Supply Device

21‧‧‧First Central First Liquid Storage Tank

22‧‧‧Second Central Second Liquid Storage Tank

3‧‧‧ dope tank

4‧‧‧ local liquid storage tank

5‧‧‧Polishing machine

11‧‧‧Pure water supply device

121‧‧‧The first liquid storage device

122‧‧‧Second liquid storage device

13‧‧‧Polishing machine

14‧‧‧ dope supply device

101‧‧‧Fifth liquid level

102‧‧‧Fourth liquid level

103‧‧‧Third level

104‧‧‧Second level

105‧‧‧first level

FIG. 1 is a schematic diagram of a polishing liquid supply system according to the present invention (in the prior art).

FIG. 2 is a schematic diagram of a polishing liquid supply system according to the present invention.

FIG. 3 is a schematic diagram of a liquid level of a liquid storage device according to the present invention.

FIG. 4 is a schematic diagram of a polishing liquid supply method according to the present invention.

The following describes the embodiments of the present invention through specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through different specific implementations, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

Please refer to Figure 2 ~ Figure 4. It should be noted that the illustrations provided in this embodiment only illustrate the basic idea of the present invention in a schematic manner, and only the components related to the present invention are shown in the drawings, rather than the number, shape and For size drawing, the type, quantity, and proportion of each component can be changed at will in actual implementation, and the component layout type may be more complicated.

Embodiment one:

As shown in FIG. 2, this embodiment provides a semiconductor silicon wafer polishing liquid supply system. The polishing liquid supply system includes at least one pure water supply device 11 and at least one raw liquid supply device 14. The pure water supply device 11 and The raw liquid supply device 14 is connected to at least one first liquid storage device 121 and at least one second liquid storage device 122. The first liquid storage device 121 and the second liquid storage device 122 are connected to at least one polishing machine 13.

Preferably, the pure water supply device 11 and the raw liquid supply device 14 are connected to at least one liquid storage device group, and each of the liquid storage device groups includes a first liquid storage device 121 and a second liquid storage device. Device 122, each liquid storage device group is connected to a polishing machine 13.

Specifically, in this embodiment, there are three first liquid storage devices 121, three second liquid storage devices 122, and three polishing machines 13. One pure water supply device 11 and one raw liquid supply device 14 are commonly connected to three first liquid storage devices 121 and three second liquid storage devices 122, and the single first liquid storage device 121 and the single second liquid storage device The device 122 constitutes a liquid storage device group and is commonly connected to a single polishing machine 13. The polishing machines 13 are not connected to each other. The raw liquid supply device 14 is a polishing liquid stock solution supply device, which may include a first polishing liquid stock solution supply device 14A and a second polishing liquid stock solution supply device 14B, which facilitates the circulating supply of the polishing liquid stock solution.

Specifically, as shown in FIG. 3, the liquid storage device is provided with a first liquid level 105 (highest liquid level), a second liquid level 104 (high liquid level), and a third liquid level 103 ( Medium level), the fourth level 102 (low level) and the fifth level 101 (lowest level) five levels. A liquid level sensor is provided on each of the liquid levels. The liquid level can be adjusted in position and quantity as needed, which is not limited here. In this embodiment, the fifth liquid level 101 (lowest liquid level) is set between 2% and 5% of the tank capacity of the liquid storage tank. The fourth liquid level 102 (low liquid level) is set between 5% and 15% of the tank capacity. The third liquid level 103 (medium liquid level) is set between 80% and 90% of the tank capacity. The second liquid level 104 (high liquid level) is set between 90% and 95% of the tank capacity. The first liquid level 105 (the highest liquid level) is set between 95% and 98% of the tank capacity. In addition, the uppermost edge of the liquid storage tank has an overflow groove. When the actual liquid level of the polishing liquid is too high, the polishing liquid is discharged through the overflow groove to prevent overflow. In other embodiments, the liquid storage device may be further marked with a scale to facilitate setting the liquid level.

Specifically, during the liquid filling process, the liquid level sensor of the fifth liquid level 101 is triggered, and the pure water supply device 11 is supplemented with deionized water; the liquid level sensor of the fourth liquid level 102 is triggered The pure water supply device 11 supplements the deionized water; the liquid level sensor of the third liquid level 103 is touched. The pure water supply device 11 stops replenishing deionized water, and the liquid storage device triggered by the third liquid level 103 sensor starts to replenish the polishing liquid; the liquid level sensor of the second liquid level 104 is triggered, Stop the liquid filling; the liquid level sensor of the first liquid level 105 is triggered, the liquid storage device stops replenishing the polishing liquid, the liquid filling system is closed and an alarm is given.

During the liquid supply process, the liquid level sensor of the first liquid level 105 is triggered, the liquid supply system of the liquid storage device is closed and an alarm is prompted; the liquid level sensor of the second liquid level 104 is not triggered; The liquid level sensor of the third liquid level 103 is not triggered; the liquid level sensor of the fourth liquid level 102 is triggered, and the liquid storage device triggered by the fourth liquid level 102 sensor stops supplying. At the same time, another liquid storage device starts to supply liquid; the liquid level sensor of the fifth liquid level 101 is triggered, the liquid storage device stops liquid supply, the liquid supply system is closed, and an alarm is given. The first liquid storage device 121 is a liquid storage device that is supplying liquid, and the second liquid storage device 122 is a liquid storage device that is filled with liquid and is waiting for liquid supply.

This embodiment further includes one or more combinations of a temperature control device and a stirring device provided in the liquid storage device.

Specifically, the temperature control device may be a heating device or a cooling device. In this way, when the wafer is polished, a polishing liquid with a certain temperature can be obtained, thereby improving the polishing effect. The stirring device may be composed of a stirring motor and a stirring blade.

It also includes one or more combinations of a circulating device and a filtering device provided in the polishing liquid supply system. The polishing liquid is supplied to the polishing machine 13 after being processed by the filtering device or the circulating device to realize the recycling of the polishing liquid. The filtering device may be connected to an input port or an output port of the liquid storage device.

In this embodiment, the polishing liquid supplemented in the liquid storage device is a silicon wafer edge. Polishing liquid for polishing the front and back surfaces of the sheet.

Embodiment two:

As shown in FIG. 4, the present invention provides an effective method for supplying a polishing liquid for a semiconductor wafer, including:

Step S1: After receiving the liquid supply signal, the first liquid storage tank starts liquid supply.

Specifically, before the step S1, the first liquid storage device 121 may first perform a liquid filling step. After the first liquid storage device 121 is filled with liquid, the polishing liquid supply system receives a liquid supply signal, and the first liquid storage tank starts to supply liquid to the polishing machine 13.

Step S2: It is determined whether the liquid supply of the first liquid storage tank is completed, if yes, step S3 is performed; if not, step S2 is continued.

Specifically, it is determined whether the liquid in the first liquid storage tank reaches the fourth liquid level 102 (low liquid level) of the first liquid storage tank, and if yes, step S3 is performed; if not, step S2 is continued.

Step S3: the first liquid storage tank stops liquid supply, the second liquid storage tank starts liquid supply, and the first liquid storage device 121 starts liquid filling.

Specifically, the first liquid storage tank is supplied with liquid, the first liquid storage tank stops supplying liquid to the polishing machine 13, at the same time the second liquid storage tank starts supplying liquid to the polishing machine 13, and the original liquid supply device 14 starts to supply the first liquid storage device. 121 filled with liquid. Of course, before the second liquid storage tank is supplied with liquid, it may also be determined whether the second liquid storage tank has been filled with liquid, and the liquid supply to the polishing machine 13 is continued until the second liquid storage tank is filled with liquid, otherwise an alarm is issued.

Step S4: determine whether the liquid supply in the second liquid storage tank is completed, if yes, go to step S5; if not, continue to step S4; specifically, determine whether the liquid in the second liquid storage tank reaches the fourth liquid in the second liquid storage tank Bit 102 (low liquid level), if yes, go to step S5; if no, go to step S4.

Step S5: The second liquid storage tank stops supplying liquid, the first liquid storage tank starts supplying liquid, and the second liquid storage tank begins to fill with liquid.

Specifically, the second liquid storage tank stops supplying liquid to the polishing machine 13, while the first liquid storage tank starts supplying liquid to the polishing machine 13, and the original liquid supply device 14 starts to fill the second liquid storage device 122. Of course, before the first liquid storage tank is supplied with liquid, it can also be determined whether the first liquid storage tank has been filled with liquid, and the liquid supply to the polishing machine 13 is continued until the first liquid storage tank is filled with liquid, otherwise an alarm is given. Step S5 ends, and step S2 can be continued. In this embodiment, the liquid level sensor is used to automatically realize the circulating liquid filling and liquid supply of the first liquid storage tank and the second liquid storage tank, which is beneficial to improving production efficiency.

The liquid filling includes the following steps:

Step S01: replenish the deionized water to the liquid level in the liquid storage device, stop replenishing the deionized water and record the replenishment amount of the deionized water. The supplemental amount of deionized water was recorded using a pure water flow meter. The pure water flow meter is connected between the pure water supply system and the liquid storage device.

Step S02: According to the preset ratio of the polishing solution to the deionized water, determine the supplementary amount of the supplementary polishing solution and replenish the polishing solution according to the supplementary amount of the deionized water.

Specifically, the replenishment amount of the polishing liquid is recorded using an integrated flow meter. The totalizing flowmeter is connected between the raw liquid supply device 14 and the liquid storage device. The totalizing flowmeter can cumulatively calculate the replenishing amount of the polishing liquid, and can also calculate the replenishing amount of each polishing liquid individually.

Step S03: Online check whether the specification of the polishing solution in the liquid storage device reaches the preset specification of the polishing solution. If yes, continue to step S03; if no, execute step S04; specifically, set a standard polishing solution in advance according to the actual use situation Specifications, the online detection of whether the polishing liquid specifications in the liquid storage device reach the preset standard polishing liquid specifications, if If yes, continue to step S03, and keep the polishing liquid specification on-line detection until the liquid supply ends; if not, go to step S04. The polishing fluid specification can have a certain error range. Wherein, the setting parameters of the polishing liquid specification include one or more of temperature, pH value and particle content.

Step S04: an alarm prompt.

Specifically, if a situation occurs during the online detection of the specification of the polishing solution that cannot reach the preset standard specification of the polishing solution, the alarm prompts and the liquid supply can be stopped, and the liquid supply is restarted until it is repeatedly detected that the specification of the polishing solution reaches the preset standard.

In summary, the semiconductor silicon wafer polishing liquid supply system of the present invention is not provided with a central liquid storage device, and at least a liquid storage device group (the first liquid storage device 121 and the second liquid storage device 122) is directly provided near each polishing machine 13 ), The polishing liquid stock solution and deionized water are directly supplied to the liquid storage device group. Among them, each liquid storage device is provided with sensors of different liquid levels (first liquid level 105, second liquid level 104, third liquid level 103, fourth liquid level 102, and fifth liquid level 101), and Corresponding logic (such as water replenishment, liquid filling, liquid supply, liquid supply stop, etc.) is set for different liquid level elements to realize automatic sequential circulation of liquid filling and liquid supply of the two liquid storage devices. The invention does not need to provide a central liquid storage device, which is beneficial to reducing the occupied space and reducing the cost of pumps and pipelines in the supply system. In addition, the polishing liquid mixing ratio of each polishing machine can be different, which is more convenient when experimenting for optimization.

Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

The above-mentioned embodiments merely illustrate the principle of the present invention and its effects, but are not intended to limit the present invention. Anyone familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications completed by those with ordinary knowledge in the technical field to which they belong without departing from the spirit and technical ideas disclosed in the present invention Or changes should still be covered by the claims of the present invention.

11‧‧‧Pure water supply device

121‧‧‧The first liquid storage device

122‧‧‧Second liquid storage device

13‧‧‧Polishing machine

14‧‧‧ dope supply device

Claims (12)

A polishing liquid supply system includes: at least one pure water supply device; at least one raw liquid supply device; the pure water supply device and the raw liquid supply device are connected to at least one first liquid storage device and at least one second liquid storage device The at least one first liquid storage device and the at least one second liquid storage device are connected to at least one polishing machine. The polishing liquid supply system according to claim 1, wherein the pure water supply device and the raw liquid supply device are connected to at least one liquid storage device group, and the at least one liquid storage device group includes the at least one first storage device And at least one second liquid storage device, the at least one liquid storage device group is connected to the at least one polishing machine. The polishing liquid supply system according to claim 1, wherein the first liquid storage device and the second liquid storage device are respectively provided with a first liquid level, a second liquid level, and a third liquid which are sequentially lowered. Level, a fourth level, and a fifth level, respectively at the first level, the second level, the third level, the fourth level, and the fifth level Set up a level sensor. The polishing liquid supply system according to claim 3, wherein a liquid level sensor of the fifth liquid level is triggered during a liquid filling process, and the pure water supply device is supplemented with deionized water; the fourth The liquid level sensor of the liquid level is triggered, and the pure water supply device is supplemented with deionized water; the liquid level sensor of the third liquid level is triggered, and the pure water supply device stops being supplemented with deionized water, so The liquid storage device triggered by the liquid level sensor starts to replenish the polishing liquid; the liquid level sensor of the second liquid level is triggered, the liquid storage device replenishes the polishing liquid; the liquid level of the first liquid level The sensor is triggered, the liquid storage device is supplemented with polishing liquid and its liquid supply system The system shuts down and alerts. The polishing liquid supply system according to claim 3, wherein during the liquid supply process, the liquid level sensor of the first liquid level is triggered, the liquid storage device stops liquid supply and its liquid supply system is closed and an alarm is issued Prompt; the liquid level sensor of the second liquid level will not be triggered; the liquid level sensor of the third liquid level will not be triggered; the liquid level sensor of the fourth liquid level will be triggered A liquid storage device triggered by the liquid level sensor stops supplying liquid, while another liquid storage device starts supplying liquid; the sensor of the fifth liquid level is triggered, and the liquid storage device stops supplying liquid and Its liquid supply system is shut down and alarmed. The polishing liquid supply system according to claim 1, wherein the polishing liquid supplemented in the liquid storage device is a silicon wafer edge, and a polishing liquid used when the front and back surfaces of the silicon wafer are polished. The polishing liquid supply system according to claim 1, further comprising one or a combination of a temperature control device and a stirring device provided in the liquid storage device. The polishing liquid supply system according to claim 1, further comprising one or a combination of a circulation device and a filtration device connected to the liquid storage device. A polishing liquid supply method includes: step S1: receiving a liquid supply signal, a first liquid storage device starts liquid supply; step S2: judging whether the first liquid storage device has completed liquid supply, and if so, performing step S3; if If no, proceed to step S2; step S3: the first liquid storage device stops liquid supply, a second liquid storage device starts liquid supply, and the first liquid storage device starts liquid filling; Step S4: determine whether the liquid supply of the second liquid storage device is completed, if yes, go to step S5; if not, continue to step S4; step S5: the second liquid storage device stops liquid supply, and the first liquid storage The device starts to supply liquid, and the second liquid storage device starts filling. The polishing liquid supply method according to claim 9, wherein the liquid filling process includes the following steps: Step S01: replenish deionized water to a third liquid level of the liquid storage device, stop replenishing deionized water and record deionized water The replenishment amount of water; step S02: determining the replenishment amount of the replenishing polishing fluid and replenishing the refining liquid according to the preset ratio of the polishing fluid to the deionized water; Whether the specification of the polishing solution in the medium reaches the preset specification of the polishing solution, if yes, continue to step S03; if no, execute step S04; step S04: alarm prompt. The polishing liquid supply method according to claim 10, wherein the replenishment amount of the deionized water is recorded using a pure water flow meter, and the replenishment amount of the polishing liquid is recorded using an integrated flow meter. The polishing liquid supply method according to claim 10, wherein the setting parameters of the polishing liquid specification include one or a combination of temperature, pH value, and particle content.