System and method for reducing vacuum leakage and storage medium

Abstract

The invention discloses a system and method for reducing vacuum leakage and a storage medium, and the method comprises the following steps: S1, a pin system receives a wafer, and starts to descend; s2, the position detection system judges whether the distance between the wafer and the carrying table meets the requirement or not; s3, if the distance meets the requirement, a vacuum adsorption hole in the carrying table is opened; if the requirement is not met, returning to the second step until the distance between the two meets the requirement; and S4, receiving the wafer by the carrying table, and carrying out process treatment. According to the scheme, opening of the vacuum adsorption holes is delayed, so that the distance between the wafer and the table top of the carrying table is small, the vacuum adsorption holes are prevented from being directly communicated with the atmosphere, and the problem of vacuum leakage is solved. The problem that the adsorption force of the process unit which shares the same vacuum generation device with the process unit is weakened, so that the position of the wafer deviates and even flies is solved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor equipment, and more particularly to a system, method and storage medium for reducing vacuum leakage. Background Art

[0002] The device used by the process unit to obtain the wafer is generally composed of a pin and a chuck (a vacuum chuck, a tool for fixing and supporting the wafer). When the external robotic arm sends the wafer into the process unit, the pin rises, adsorbs the wafer, and drives the wafer to move closer to the chuck. When the pin adsorbs the wafer, the vacuum hole of the chuck also opens, and when the wafer approaches the chuck, it adsorbs the wafer.

[0003] In the prior art, the chuck opens the vacuum when the pin just absorbs the wafer. At this time, the wafer is far away from the chuck, and the vacuum hole of the chuck is connected to the atmosphere, causing vacuum leakage, which weakens the vacuum absorption force in other process units that share the vacuum generator with the chuck, causing the internal wafers of other process units to move or even fly during the process. This solution aims to reduce the vacuum leakage generated when the process unit receives the wafer and prevent it from affecting other process units. Summary of the invention

[0004] The object of the present invention is to provide a system, method and storage medium for reducing vacuum leakage, aiming to reduce the vacuum leakage generated when the process unit receives the wafer, prevent the impact on other process units, and solve the technical problems existing in the above-mentioned background technology.

[0005] The technical solution of the present invention provides a method for reducing vacuum leakage, comprising the following steps:

[0006] S1: The pin system receives the wafer and starts to descend;

[0007] S2: The position detection system determines whether the distance between the wafer and the mounting table meets the requirements;

[0008] S3: If the distance meets the requirement, the vacuum adsorption hole on the mounting table is opened; if it does not meet the requirement, return to the second step until the distance between the two meets the requirement;

[0009] S4: The stage receives the wafer and performs process processing.

[0010] In a preferred embodiment, when the requirements in step S3 are met, the distance between the wafer and the vacuum adsorption hole is no greater than 0.1 mm.

[0011] In a preferred embodiment, after step S3 and before step S4, the pressure of the vacuum adsorption hole is monitored. When the change value of the monitored vacuum pressure is greater than a threshold value, an alarm is sounded, the vacuum adsorption hole is closed, and the process unit flow is stopped.

[0012] A system for reducing vacuum leakage, comprising a pin system, a chuck system and a position detection system;

[0013] The pin needle system includes a plurality of pin needles and a driving device for driving the pin needles to rise and fall, and the pin needles are arranged on the driving device through a driving arm; the chuck system includes a loading platform and a vacuum channel, and a vacuum adsorption hole is arranged on the loading platform, and the vacuum adsorption hole is connected to the vacuum channel, and the vacuum channel is connected to a vacuum generator.

[0014] In a preferred embodiment, the position detection system comprises a distance sensor, and the distance sensor is arranged on the mounting platform.

[0015] In a preferred embodiment, the position detection system comprises a slide and a contact switch, and the slide is arranged on a driving arm of the pin system.

[0016] In a preferred embodiment, the position detection system is a software algorithm, which is calibrated in advance to calculate the distance between the top of the pin needle and the table surface, the speed at which the pin needle descends, and the position of the wafer when the vacuum adsorption hole is opened. Based on these three, the time required for the pin needle to descend to the target position is calculated by dividing the distance by the speed, and the time is used to determine whether the distance between the two meets the requirements.

[0017] In a preferred embodiment, before performing each calculation step, the parameters are self-calibrated.

[0018] In a preferred embodiment, it also includes a pressure sensing device for detecting vacuum pressure.

[0019] A storage medium storing a computer program, which implements the above method when executed by a processor.

[0020] The beneficial effects of the technical solution of the present invention are:

[0021] This solution delays the opening of the vacuum adsorption hole, making the distance between the wafer and the table surface smaller, and preventing the vacuum adsorption hole from being directly connected to the atmosphere, thereby solving the vacuum leakage problem. It also avoids the problem of the process unit that shares the same vacuum generating device with this process unit weakening its adsorption force, causing the wafer position to shift or even fly. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the system structure for reducing vacuum leakage of the present invention.

[0023] Figure 2 This is a diagram showing the arrangement of the distance sensor in the first embodiment of the present invention.

[0024] Figure 3 1 is a diagram showing the position relationship between the slide and the contact switch in the second embodiment of the present invention.

[0025] Explanation of the reference numerals: 1. pin; 2. chuck system; 3. vacuum adsorption hole; 4. vacuum generator; 5. vacuum channel; 6. driving device; 7. driving arm; 8. wafer; 9. pressure sensing device; 10. distance sensor; 11. slider; 12. contact switch. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below. The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and design various embodiments with various modifications suitable for specific uses.

[0027] like Figure 1 As shown, the technical solution of the present invention provides a system for reducing vacuum leakage, including a pin system, a chuck system 2 and a position detection system.

[0028] The pin needle system includes a plurality of pin needles 1 and a driving device 6 for driving the pin needles 1 to perform lifting motion. In this embodiment, three pin needles 1 are arranged, and the pin needles 1 are arranged on the driving device 6 through a driving arm 7. When the driving device 6 moves, it drives the driving arm 7 to move, thereby indirectly driving the pin needles 1 to lift and lower.

[0029] The chuck system 2 includes a mounting table and a vacuum channel 5. The mounting table is provided with a vacuum adsorption hole 3, and the vacuum adsorption hole 3 is connected to the vacuum channel 5, and the vacuum channel 5 is connected to a vacuum generator 4. Under the action of the vacuum generator 4, air is pumped outward through the vacuum pipe to form a negative pressure at the vacuum adsorption hole 3, thereby achieving adsorption and fixation of the wafer 8, and the end surface of the vacuum adsorption hole 3 is flush with the table surface of the mounting table.

[0030] The position detection system is used to detect the distance between the wafer 8 and the table surface to ensure that the wafer 8 is evacuated only when it is close to the vacuum adsorption hole 3, avoiding direct contact between the vacuum adsorption hole 3 and the atmosphere, resulting in vacuum leakage, thereby weakening the adsorption force of the process unit sharing the same vacuum generating device with this process unit, causing the position of the wafer 8 to shift or even fly.

[0031] like Figure 2 As shown, as the first embodiment of the present scheme, the position detection system includes a distance sensor 10, and the distance sensor 10 is arranged on the mounting table. When the pin needle 1 receives the wafer to descend, the distance sensor 10 detects the distance between the wafer and the mounting table in real time. When it is detected that the distance between the wafer 8 and the mounting table is lower than the threshold, the vacuum adsorption hole 3 is opened to adsorb the wafer 8.

[0032] like Figure 3 As shown in the figure, as the second embodiment of the present scheme, the position detection system includes a slide 11 and a contact switch 12, and the slide 12 is arranged on the driving arm 7 of the pin needle system. The contact switch is arranged at the target position of the chuck system 2, and the target position is a pre-calibrated position. When the pin needle 1 receives the wafer and descends, the driving arm 7 drives the slide 11 to descend at the same time. When the slide 11 reaches the contact switch 12 and triggers the contact switch 12, it indicates that the distance between the wafer 8 and the vacuum adsorption hole 3 is at the target distance. At this time, the vacuum adsorption hole 3 is opened to adsorb the wafer 8.

[0033] As the third embodiment of this scheme, the position detection system is a software algorithm. Through prior calibration, the distance between the top of the pin needle 1 and the table surface, the speed of the pin needle 1 falling, and the position of the wafer 8 when the vacuum adsorption hole 3 is opened are calculated. Based on the three, the time required for the pin needle 1 to fall to the target position is calculated by dividing the distance by the speed, and whether the distance between the two meets the requirements is judged according to the time. The timing starts when the pin needle 1 receives the wafer descent. When it is detected that the pin needle 1 descent time reaches the set time, the vacuum adsorption hole 3 is opened to adsorb the wafer 8. In this embodiment, due to the changes in the mechanical structure, the parameters are self-calibrated before each calculation step to avoid calculation errors.

[0034] The technical solution of the present invention provides a method for reducing vacuum leakage, comprising the following steps:

[0035] S1: The pin system receives wafer 8 and starts to descend;

[0036] S2: The position detection system determines whether the distance between the wafer 8 and the mounting table meets the requirement;

[0037] S3: If the distance meets the requirement, the vacuum adsorption hole 3 on the mounting table is opened; if not, the process returns to the second step until the distance between the two meets the requirement. When the requirement is met, the distance between the wafer 8 and the vacuum adsorption hole 3 is not greater than 0.1 mm.

[0038] If the distance between wafer 8 and vacuum adsorption hole 3 is too large, vacuum leakage will occur, which will weaken the adsorption force of chuck system in other process units. Therefore, when vacuum adsorption hole 3 is opened, the smaller the distance between wafer 8 and vacuum adsorption hole 3 is, the smaller the impact on other process units is. However, if the distance between wafer 8 and vacuum adsorption hole 3 is too small, there is a problem of inaccurate distance detection. If a high-precision position detection system is set in the process unit, it will increase the cost. The applicant has found through experiments that when the distance between wafer 8 and vacuum adsorption hole 3 is 0.1mm, although vacuum adsorption hole 3 is in contact with the atmosphere, due to the obstruction of wafer 8, the vacuum pressure in other process units fluctuates by about 10kpa, and this pressure fluctuation has little effect on the adsorption force of wafer 8. Therefore, the distance between wafer 8 and vacuum adsorption hole 3 in this scheme is set to be no more than 0.1mm.

[0039] Before performing step S4, the vacuum pressure value is detected by the pressure sensing device 9, and the pressure of the vacuum adsorption hole 3 is monitored. When the change value of the vacuum pressure is monitored to be greater than the threshold, an alarm is sounded, and the vacuum adsorption hole 3 is closed, and the process of this process unit is stopped. By monitoring the pressure of the vacuum adsorption hole 3, when the vacuum pressure change exceeds the threshold, it means that the process treatment in other process units will be affected. Therefore, the vacuum adsorption hole 3 is closed to first ensure the process flow of the process unit being carried out.

[0040] S4: When the vacuum pressure value is within the threshold range and the distance meets the requirement, the wafer 8 is received by the chuck system 2 for subsequent process processing.

[0041] The technical solution of the present invention provides a storage medium storing a computer program, and the program implements the above method when executed by a processor.

[0042] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field and related fields without creative work should fall within the scope of protection of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention are implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. A method for reducing vacuum leakage, characterized in that: The steps include: S1: The pin system receives the wafer and starts to descend; S2: The position detection system determines whether the distance between the wafer and the mounting table meets the requirements; S3: If the distance meets the requirement, the vacuum adsorption hole on the mounting table is opened; if it does not meet the requirement, return to the second step until the distance between the two meets the requirement; S4: The stage receives the wafer and performs process processing.

2. A method for reducing vacuum leakage according to claim 1, characterized in that: When the requirements in step S3 are met, the distance between the wafer and the vacuum adsorption hole is no greater than 0.1 mm.

3. A method for reducing vacuum leakage according to claim 1, characterized in that: After step S3 and before step S4, the pressure of the vacuum adsorption hole is monitored. When the change value of the vacuum pressure is monitored to be greater than a threshold value, an alarm is sounded, and the vacuum adsorption hole is closed, and the process unit flow is stopped.

4. A method for reducing vacuum leakage according to claim 1, characterized in that: The position detection system includes a distance sensor, and the distance sensor is arranged on the mounting table.

5. A method for reducing vacuum leakage according to claim 1, characterized in that: The position detection system comprises a slide and a contact switch, wherein the slide is arranged on a driving arm of a pin system.

6. A method for reducing vacuum leakage according to claim 1, characterized in that: The position detection system is a software algorithm. Through prior calibration, it calculates the distance between the top of the pin needle and the surface of the mounting table, the speed at which the pin needle descends, and the position of the wafer when the vacuum adsorption hole is opened. Based on these three, the time required for the pin needle to descend to the target position is calculated by dividing the distance by the speed, and the time is used to determine whether the distance between the two meets the requirements.

7. A method for reducing vacuum leakage according to claim 6, characterized in that: Before each calculation step, the parameters are self-calibrated.

8. A system for reducing vacuum leakage according to claim 1, characterized in that: Including pin system, chuck system and position detection system; The pin needle system includes a plurality of pin needles and a driving device for driving the pin needles to rise and fall, and the pin needles are arranged on the driving device through a driving arm; the chuck system includes a loading platform and a vacuum channel, and a vacuum adsorption hole is arranged on the loading platform, and the vacuum adsorption hole is connected to the vacuum channel, and the vacuum channel is connected to a vacuum generator.

9. A system for reducing vacuum leakage according to claim 8, characterized in that: A pressure sensing device for detecting vacuum pressure is also included.

10. A storage medium storing a computer program, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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