TWI611504B - Plasma etching device, wafer lifting device and lifting method thereof - Google Patents

Abstract

The invention discloses a plasma etching equipment, a wafer lifting device and a lifting method thereof. A first lifting element is used to complete a first lifting stage, and a micro-cylinder drives the ejector element to lift and lift the wafer to separate the wafer from the electrostatic chuck. The second jacking stage is completed using the second jacking element, and the cylinder further drives the micro-cylinder and the ejector element to jack the wafer to a set distance. The invention adopts a micro cylinder to realize the first stage lifting process. The micro cylinder is used to adjust the jacking height and jacking speed of the ejector rod to obtain the same jacking time and jacking force. The stroke of the micro cylinder is short and the micro cylinder is reasonably controlled. The amount of air intake can achieve a gentle and stable jacking process to prevent damage to the wafer. The micro-cylinder is small and saves space. Multiple micro-cylinders are used to achieve the first stage of jacking, and one cylinder is used to achieve the second stage of jacking. It is more flexible and reduces the cost. It does not need to use helium and avoids the risk of wafer contamination.

Description

Plasma etching equipment, wafer lifting device and lifting method

The invention relates to a plasma etching equipment, a wafer lifting device and a lifting method thereof.

In the plasma etching equipment, the electrostatic chuck uses static electricity to firmly adsorb and fix the wafer, and the wafer is fixed on the electrostatic chuck for a corresponding etching operation. After the etching operation is completed, the wafer needs to be taken out for subsequent processing. Only when the electrostatic charge is completely released, the electrostatic chuck no longer has an adsorption force on the wafer, and at this time, the wafer can be lifted from the electrostatic chuck by using a lifting device. Because it is difficult to ensure that the electrostatic charge is completely released, if there is still a static charge, there will still be a local adsorption force. Therefore, when the wafer is jacked up, it is easy for the wafer to occur under the interaction of the jacking force and the residual adsorption force. Broken, so a smart lifting device needs to be designed to ensure that the chip can be safely lifted.

Generally speaking, the jacking process includes two stages: the first jacking stage, which lifts the wafer to 0.5 to 3 mm to separate the wafer from the electrostatic chuck; the second jacking stage, which continues to jack the wafer to 9.5 to 15 mm, So that the robot can remove the wafer. The first lifting stage is very critical. The required lifting force is small, and it is best that the lifting force is adjustable, and the lifting process must be slow and gentle, otherwise the risk of wafer damage will be great.

At present, a variety of lifting devices and lifting methods have been applied to plasma etching equipment. For example, US patent US8628675B2 discloses a lifting device. As shown in FIG. 1, a semiconductor wafer 406 is placed on an electrostatic chuck 404. The wafer 406 is jacked by a jacking pin 428. The jacking pin 428 is connected to the pin lifting yoke 430. The pin lifting yoke 430 is connected to the motor 446 through the lead screw 444. When the wafer is required to be jacked, the motor 446 drives the pin lifting yoke 430. Drive the lifting pin 428 upward to lift the chip 406. During the lifting process, the strain gauge 442 detects the lifting force data in real time and transmits it to the digital signal processor (DSP) 450. The motor controller 452 transmits the control signal to the motor. 446. Adjust the lifting force and lifting speed of the motor in real time. In this way, both the lifting force and the lifting speed can be adjusted quickly and accurately to ensure the safety of the chip during the lifting process, but the system complexity and cost of this method are relatively high. The US patent case US8628675B2 also discloses a jacking device, which uses two cylinders to realize the two stages of the jacking process. As shown in FIG. 2A, the first cylinder 304 is provided with a first piston 301 and the second cylinder 305 is provided. A second piston 302 is provided. As shown in FIG. 2B, in the first lifting stage, the second cylinder 305 receives air, the second piston 302 moves upward, the plug 312 lifts upward, and at the same time drives the first piston 301 to lift upward. In the second lifting stage, as shown in FIG. 2C, the first cylinder 304 receives air, the first piston 301 moves upward, and the plug 311 lifts upward. Adopting this lifting method requires two cylinders, which takes up too much space, and the adjustment accuracy of large cylinders is not high. As shown in Figure 3, there is another way in the conventional technology, using helium to achieve the first jacking stage, and using cylinder 206 to achieve the second jacking stage. It can be judged by detecting the flow and pressure data of helium Whether the first stage of the wafer lifting is successful, and by adjusting the gas flow of the cylinder 206 to control the lifting speed and the lifting height. However, due to the introduction of helium in this method, the wafer will be contaminated, and the helium gas flow will cause the wafer to shift.

The invention provides a plasma etching device, a wafer lifting device and a lifting method, which can realize a stable and gentle lifting process, avoid damage and pollution to the wafer, save space, reduce costs, and have strong flexibility. And operability.

In order to achieve the above object, the present invention provides a wafer lifting device, which is arranged in a plasma etching chamber, an equipment disc is arranged in the etching chamber, an electrostatic chuck is arranged on the equipment disc, the wafer is adsorbed on the electrostatic chuck, the electrostatic chuck and the equipment The disks each have a plurality of through-holes. The through-holes on the equipment disk and the through-holes on the electrostatic chuck form a guide channel. The wafer lifting device includes: a plurality of first lifting elements that pass through the guide channel and are arranged below the wafer. It is used to complete the first jacking stage, to lift the wafer to be separated from the electrostatic chuck; the second jacking element, which is mechanically connected to all the first jacking elements, is used to complete the second jacking stage, and to continue to lift the wafer. The first jacking component includes: a micro cylinder and a jack member connected to the micro cylinder. The micro cylinder drives the jack member to lift the wafer by a piston; the second jack includes a cylinder and a connecting cylinder and A plurality of connection elements of the micro-cylinder. The cylinder uses the cylinder piston to further drive the micro-cylinder and the ejector element through the connection element to lift the wafer to the setting. Away.

Preferably, the micro-cylinder is arranged in the guide sleeve and can move up and down along the axial direction of the guide sleeve, and the guide sleeve is fixedly disposed below each guide channel.

Preferably, the number of the first jacking components is three or more.

Preferably, a stopper is provided in the miniature cylinder, and the stopper prevents the piston from continuing to move upward.

Preferably, the setting position of the stop block satisfies the following conditions: when the piston is located at the initial position of the bottom of the micro-cylinder, the distance between the bottom surface of the stop block and the top surface of the piston is H1 = 0.5 to 3 mm.

Preferably, the ejector element is disposed in the guide channel, and the ejector element includes an ejector main body and an ejector rod provided in the ejector main body, and the bottom of the ejector main body is sealedly connected to the top of the microcylinder by a bellows. The ejector pin is embedded in the top of the ejector body through a seal ring. The bottom of the ejector pin is fixedly connected to the piston of the microcylinder. With the drive of the piston, the ejector pin can be lifted upward. The tip of the ejector pin contacts the wafer and ejects the wafer. .

Preferably, the wafer lifting device further includes a control device. The control device includes a plurality of thrust detectors, which are respectively disposed at the bottom of each piston, and are used to detect thrust magnitude data. The number of the thrust detectors is similar to that of the first lifting component. The number is the same; a plurality of contact detectors, which are arranged at the bottom of the wafer and located above the ejector pins respectively, are used to detect the time when the ejector pins contact the wafer; the number of contact detectors is the same as the number of the first jacking elements; the controller, It is electrically connected to each thrust detector, each contact detector and each micro-cylinder, and the controller realizes the synchronous control of the plurality of first jacking elements to ensure that the thrust of each jack is the same, and that the jacks contact the chip at the same time. .

Preferably, the first jacking assembly further includes: a seal ring flange, which is disposed between the equipment plate and the guide sleeve for isolating and sealing.

Preferably, a cylinder stop block is provided in the cylinder, and the cylinder stop block prevents the cylinder piston from continuing to move upward.

Preferably, the setting position of the cylinder stop block satisfies the following conditions: when the cylinder piston is located at the initial position of the cylinder bottom, the distance between the bottom surface of the cylinder stop block and the top surface of the cylinder piston is H2 = 9.5 to 15 mm.

Preferably, the connecting elements in the second lifting element include: a plurality of lifting arms, each of which is fixedly connected to a cylinder piston, and the number of the lifting arms is the same as the number of the first lifting components; the plurality of plunger rods The upper end of each plunger rod is correspondingly connected to the bottom of the micro-cylinder, and the lower end of each plunger rod is fixedly connected to a lifting arm, respectively. The number of plunger rods is the same as the number of the first lifting components.

In order to achieve the above object, the present invention further provides a wafer lifting method realized by using the wafer lifting device described above, including the following steps: Step S1, using a first lifting element to complete a first lifting stage, in a plasma-on state The wafer is lifted to a distance of 0.5 to 3 mm from the electrostatic chuck to separate the wafer from the electrostatic chuck; the air inlet of the micro-cylinder inputs gas, and the piston drives the jack to lift up. During the lifting process, the control device controls the micro-cylinder's The amount of air intake to control the thrust of all ejectors is the same and all ejectors contact the wafer for the same time. When the piston contacts the stop block, it stops moving and the ejector stops lifting, keeping the current intake of the micro-cylinder unchanged. Step S2: Use the second jacking element to complete the second jacking stage, and continue to jack the wafer to 9.5 to 15mm away from the electrostatic chuck in the plasma closed state; the gas is input to the intake end of the cylinder, and the cylinder piston drives a plurality of jacks The lifting arm moves upward, and the lifting arm drives the plunger rod connected to it to move upward. A plurality of plunger rods respectively drive the miniature cylinder and the lifting rod to lift upward. When the cylinder until the piston contacts the stopper cylinder, cylinder-piston stops moving; step S3, the wafer is removed after the first and the second lifting member lifting element drops back to the initial position, waiting for a lifting process.

Preferably, the first jack-up phase is performed in a plasma-on state.

Preferably, the second jacking stage is performed in a plasma-off state.

Preferably, the first jacking element and the second jacking element descending and returning to the initial position specifically include the following steps: the air intake end of the micro-cylinder stops inputting gas, the gas in the cylinder is exhausted from the air-exiting end, and the piston descends to the initial position. The rod is lowered to the initial position. The top end of the ejector rod is lower than the bottom surface of the wafer. The air intake end of the cylinder stops inputting gas, the gas in the cylinder is exhausted from the outlet end, the cylinder piston descends to the initial position, and the lift arm and plunger rod descend to the initial position. The miniature cylinder descends to the initial position.

In order to achieve the above object, the present invention further provides a plasma etching device, including: an etching cavity, an equipment disc disposed in the etching cavity, an electrostatic chuck disposed on the equipment disc, a wafer being adsorbed on the electrostatic chuck, and an electrostatic chuck Both the device tray and the device tray have a plurality of through holes. The through holes on the device tray and the through holes on the electrostatic chuck form a guide channel. The plasma etching device further includes the wafer lifting device set in the plasma etching chamber.

The invention has the following advantages:

1. The use of a miniature cylinder to achieve the first stage of the jacking process, the use of a miniature cylinder to adjust the jacking height and jacking speed, to obtain the same jacking time and jacking force, short stroke of the miniature cylinder, reasonable control of the miniature cylinder The amount of air intake can achieve a gentle and stable jacking process to prevent damage to the wafer;

2. The miniature cylinder is small in size and saves space. The use of multiple miniature cylinders for the first stage of jacking up, and the use of one cylinder for the second stage of jacking up are more flexible and reduce costs;

3. No helium is needed, avoiding the risk of wafer contamination.

Hereinafter, preferred embodiments of the present invention will be described in detail based on FIGS. 4 to 8.

As shown in FIG. 4, the present invention provides a wafer lifting device, which is arranged in a plasma etching chamber, an equipment disc 3 is arranged in the etching chamber, an electrostatic chuck 2 is arranged on the equipment disc 3, and a wafer is adsorbed on the electrostatic chuck 2 On the electrostatic chuck 2 and the device tray 3, there are a plurality of through holes. The through hole on the device tray 3 and the through hole on the electrostatic chuck 2 form a guide channel 21. The wafer lifting device includes:

A plurality of first jacking elements, which are arranged below the wafer through the guide channel 21, for completing the first jacking stage, lifting the wafer to a distance of 0.5 to 3 mm from the electrostatic chuck to separate the wafer from the electrostatic chuck;

The second jacking element is mechanically connected to all the first jacking elements and is used to complete the second jacking stage, and continues to jack the wafer to a distance of 9.5 to 15 mm from the electrostatic chuck so that the robot can remove the wafer.

The first jacking assembly contains:

A guide sleeve 103, which is fixedly disposed below each guide channel 21;

The micro-cylinder 101 is arranged in the guide sleeve 103 and can move up and down along the axial direction of the guide sleeve 103. The micro-cylinder 101 has a piston 102. Under the impulse of the gas, the piston 102 can move up and down in the micro-cylinder 101. A stopper 107 is also provided in the cylinder 101, and the stopper 107 prevents the piston 102 from continuing to move upwards;

The ejector element is disposed in the guide channel 21. As shown in FIG. 5, the ejector assembly includes an ejector main body 1041 and an ejector 104 provided in the ejector main body 1041. The bottom of the ejector main body 1041 is corrugated. The tube 105 is hermetically connected to the top of the microcylinder 101. The rod 104 is embedded in the top of the rod main body 1041 through a seal ring 1042. The bottom of the rod 104 is fixedly connected to the piston 102 of the microcylinder 101. Driven by the piston 102, The ejector pin 104 can be lifted upward, and the top end of the ejector pin 104 contacts the wafer 1 and lifts the wafer 1.

The first jacking assembly further includes a sealing ring flange 106, which is disposed between the equipment plate 3 and the guide sleeve 103. Since the vacuum rod is above the ejector pin 104, the flange sealing ring 106 mainly isolates from the outside gas. Function, the sealing ring flange 106 contacts the bottom surface of the equipment tray 3 and the inner wall of the guide sleeve 103 to achieve a sealing effect.

As shown in Figure 4, the second jacking element includes:

The air cylinder 201 has a cylinder piston 202. The gas cylinder pushes the cylinder piston 202 up and down in the cylinder 201. The cylinder 201 is also provided with a cylinder stop block 205, which prevents the cylinder piston 202 from moving upwards. ;

A plurality of lifting arms 203, each of which is fixedly connected to the cylinder piston 202, and the number of the lifting arms 203 is the same as the number of the first lifting components;

A plurality of plunger rods 204, the upper end of each plunger rod 204 is correspondingly connected to the bottom of the microcylinder 101, the lower end of the plunger rod 204 is fixedly connected to a lifting arm 203, and the number of plunger rods 204 is the same as the first lifting The number of components is the same.

After the etching process is completed, the first lifting stage is first completed by the first lifting component, and the wafer is lifted to a distance of 0.5 to 3 mm from the electrostatic chuck to separate the wafer from the electrostatic chuck. Specifically, the intake end of the micro-cylinder 101 Input the gas, push the piston 102 to move upwards, and at the same time drive the ejector rod 104 in the ejector element to move upwards. The top of the ejector rod 104 contacts the wafer 1 and rises further, and lifts the wafer 1 until the piston 102 contacts the stopper 107. After stopping the movement, the ejector rod 104 also stops. Then the second lifting stage is completed by the second lifting element, and the wafer is continuously lifted to a distance of 9.5 to 15 mm from the electrostatic chuck so that the robot can remove the wafer. Specifically, the air inlet of the cylinder 201 inputs gas to push the cylinder piston 202 The upward movement drives multiple lifting arms 203 and multiple plunger rods 204 to move upward simultaneously, and simultaneously drives the micro cylinder 101 and the ejector rod 104 to move upward. During the ascent of the micro cylinder 101 and the ejector rod 104, the bellows 105 contracts until The cylinder piston 202 stops moving after contacting the cylinder stop block 205. At this time, the wafer is lifted to a distance of 9.5 to 15 mm from the electrostatic chuck, the air intake of the cylinder 201 stops inputting gas, and the cylinder 201 stops driving the piston 202 to complete the jacking process.

In order to ensure the uniform distribution of the lifting force, a plurality of first lifting elements are provided, and the number of the first lifting elements is three or more. As shown in FIG. 6, in this embodiment, three first jacking components are provided, which are distributed in isosceles triangles at the positions of the first hole, the second hole, and the third hole on the electrostatic chuck 2. If all the ejector elements are directly connected to the cylinder 201 according to the conventional setting, the first and second jacking stages are directly implemented. Since the ejector 204 is only bound by the elastic force of the seal ring 1042 during the jacking process, The lack of a stop device makes it difficult to control the jacking distances of multiple ejectors 204, and it is difficult to obtain the same jacking distance. When one of the ejectors 204 has already touched the wafer 1, the other ejectors 204 may not have touched the wafer yet. 1, or maybe all of the ejector pins 204 are in contact with wafer 1 at the same time, but because the electrostatic charge on electrostatic chuck 2 is not completely released, the charge distribution on electrostatic chuck 2 is uneven, and some holes are facing the wafer. The suction force is large, and the suction force on the wafer is small in some vacancies. At this time, the same jacking force is used to drive the ejector rod 204, which will cause the ejector rod 204 at some hole positions to be jacked up, but the ejector rods at some hole positions will be lifted. The lift is not enough to overcome the suction and cannot lift the wafer, which will inevitably cause the wafer to break. In the present invention, each first jacking element is individually configured with a micro cylinder 101, and each of the ejector elements is driven by the micro cylinder 101. The micro cylinder 101 has a small volume and can be disposed in a guide sleeve. The stroke is short. The micro-cylinder 101 is used to control the jacking force and jacking time of each ejector element, so that the ejection height of each ejector 104 is consistent, and the wafer and the electrostatic chuck are safely separated.

In order to better control the first jacking element to achieve the first jacking stage, the jacking time and jacking speed can be adjusted by a control device. As shown in Figure 7, the control device includes:

A plurality of thrust detectors 108, which are respectively disposed at the bottom of each piston 102 and are used to detect thrust magnitude data, and the number of the thrust detectors 108 is the same as the number of the first jacking components;

A plurality of contact detectors 109, which are arranged at the bottom of the wafer 1, respectively above the ejector pins 104, and are used to detect the time when the ejector pins 104 contact the wafer; the number of the contact detectors 109 is the same as the number of the first jacking elements;

A controller (not shown), which is electrically connected to each thrust detector 108, each contact detector 109, and each micro-cylinder 101. The controller realizes synchronous control of a plurality of first jacking components. In other words, the thrust detected by the thrust detector 108 and the contact time detected by the contact detector 109 are compared with the preset thrust and contact time, and the difference between the actual thrust and contact time and the set thrust and contact time is calculated. Through PID control calculation, the intake air pressure and speed of the micro-cylinder 101 can be adjusted in real time, so that the rising speed of the piston 102 can be adjusted in real time, and the lifting height and lifting force of the ejector rod 104 can be further controlled to ensure the same thrust of each ejector rod. , Each ejector contacts the wafer for the same time.

The invention also provides a plasma etching equipment, comprising: an etching cavity, an equipment disc 3 arranged in the etching cavity, an electrostatic chuck 2 arranged on the equipment disc 3, a wafer being adsorbed on the electrostatic chuck 2, and an electrostatic chuck 2 And the device tray 3 has a plurality of through holes, the through holes on the device tray 3 and the through holes on the electrostatic chuck 2 form a guide channel 21;

The plasma etching equipment further includes a wafer lifting device disposed in the plasma etching chamber. The wafer lifting device includes:

A plurality of first jacking elements, which are arranged below the wafer through the guide channel 21, for completing the first jacking stage, lifting the wafer to a distance of 0.5 to 3 mm from the electrostatic chuck to separate the wafer from the electrostatic chuck;

The second jacking element is mechanically connected to all the first jacking elements and is used to complete the second jacking stage, and continues to jack the wafer to a distance of 9.5 to 15 mm from the electrostatic chuck so that the robot can remove the wafer.

The first jacking assembly contains:

A guide sleeve 103, which is fixedly disposed below each guide channel 21;

The micro-cylinder 101 is arranged in the guide sleeve 103 and can move up and down along the axial direction of the guide sleeve 103. The micro-cylinder 101 has a piston 102. Under the impulse of the gas, the piston 102 can move up and down in the micro-cylinder 101. A stopper 107 is also provided in the cylinder 101, and the stopper 107 prevents the piston 102 from continuing to move upwards;

The ejector element is provided in the guide passage 21, and the ejector element includes an ejector main body 1041 and an ejector 104 provided in the ejector main body 1041. The bottom of the ejector main body 1041 is connected to The top is hermetically connected. The top rod 104 is embedded in the top of the top rod body 1041 through a seal ring 1042. The bottom of the top rod 104 is fixedly connected to the piston 102 of the microcylinder 101. With the drive of the piston 102, the top rod 104 can be jacked up. The top of the ejector pin 104 contacts the wafer 1 and lifts the wafer 1.

The first jacking assembly further includes a sealing ring flange 106, which is disposed between the equipment plate 3 and the guide sleeve 103. Since the vacuum rod is above the ejector pin 104, the flange sealing ring 106 mainly isolates from the outside gas. Function, the sealing ring flange 106 contacts the bottom surface of the equipment tray 3 and the inner wall of the guide sleeve 103 to achieve a sealing effect.

The second jacking element contains:

The air cylinder 201 has a cylinder piston 202. The gas cylinder pushes the cylinder piston 202 up and down in the cylinder 201. The cylinder 201 is also provided with a cylinder stop block 205, which prevents the cylinder piston 202 from moving upwards. ;

A plurality of lifting arms 203, each of which is fixedly connected to the cylinder piston 202, and the number of the lifting arms 203 is the same as the number of the first lifting components;

A plurality of plunger rods 204, the upper end of each plunger rod 204 is correspondingly connected to the bottom of the microcylinder 101, the lower end of the plunger rod 204 is fixedly connected to a lifting arm 203, and the number of plunger rods 204 is the same as the first lifting The number of components is the same.

The number of the first jacking components is three or more.

The wafer lifting device further includes a control device, and the control device includes:

A plurality of thrust detectors 108, which are respectively disposed at the bottom of each piston 102 and are used to detect thrust magnitude data, and the number of the thrust detectors 108 is the same as the number of the first jacking components;

A plurality of contact detectors 109, which are arranged at the bottom of the wafer 1, respectively above the ejector pins 104, and are used to detect the time when the ejector pins 104 contact the wafer; the number of the contact detectors 109 is the same as the number of the first jacking elements;

A controller (not shown), which is electrically connected to each thrust detector 108, each contact detector 109, and each micro-cylinder 101. The controller realizes synchronous control of a plurality of first jacking components. In other words, the thrust detected by the thrust detector 108 and the contact time detected by the contact detector 109 are compared with the preset thrust and contact time, and the difference between the actual thrust and contact time and the set thrust and contact time is calculated. Through PID control calculation, the intake air pressure and speed of the micro-cylinder 101 can be adjusted in real time, so that the rising speed of the piston 102 can be adjusted in real time, and the lifting height and lifting force of the ejector rod 104 can be further controlled to ensure the same thrust of each ejector rod. , Each ejector contacts the wafer for the same time.

The invention also provides a wafer lifting method, which includes the following steps:

Step S1, using the first jacking component to complete the first jacking stage, jacking the wafer to a distance of 0.5 to 3 mm from the electrostatic chuck to separate the wafer from the electrostatic chuck;

Step S2, using the second lifting element to complete the second lifting stage, and continuing to lift the wafer to a distance of 9.5 to 15 mm from the electrostatic chuck;

Step S3: After the wafer is removed, the first jacking element and the second jacking element are lowered and restored to the initial positions, and wait for the next jacking process.

As shown in FIG. 8A, in step S1, the first jacking stage is performed in a plasma-on state in order to better release the electrostatic charge on the electrostatic chuck. The first jacking stage specifically includes the following steps:

Air is input to the inlet of the micro-cylinder 101 (common dry air is generally used as the input air, and the independent CDA system circuit is used to provide dry air). The piston 102 drives the ejector 104 to lift upward. During the lift, the control device By controlling the air intake of the micro-cylinder 101, the thrust of all the ejectors is controlled to be the same, and all the ejectors are in contact with the wafer for the same time. When the piston 102 contacts the stopper 107, it stops moving and the ejector 104 stops lifting. The current intake amount of the micro-cylinder 101 is kept unchanged.

As shown in FIG. 8C, the setting position of the stopper 107 satisfies the following conditions: When the piston 102 is located at the initial position of the bottom of the miniature cylinder 101, the distance between the bottom surface of the stopper 107 and the top surface of the piston 102 is H1 = 0.5 to 3 mm .

After the entire first jacking stage is completed, the distance between the wafer and the electrostatic chuck is H1 = 0.5 to 3 mm.

As shown in FIG. 8B, in step S2, the second jacking stage is performed in a plasma off state, and the second jacking stage specifically includes the following steps:

Air is input to the intake end of the cylinder 201 (generally the input air is dry air, and the independent CDA system circuit is used to provide dry air). The cylinder piston 202 drives a plurality of lifting arms 203 to move upward, and the lifting arms 203 drive the connected The plunger rod 204 moves upward, and the plurality of plunger rods 204 respectively drive the micro-cylinder 101 and the ejector rod 104 to lift upward until the cylinder piston 202 stops moving when the cylinder piston 202 contacts the cylinder stop block 205.

The setting position of the cylinder stop block 205 satisfies the following conditions: When the cylinder piston 202 is located at the initial position of the bottom of the cylinder 201, the distance between the bottom surface of the cylinder stop block 205 and the top surface of the cylinder piston 202 is H2 = 9.5 to 15 mm.

After the entire second jacking phase is completed, the distance between the wafer and the electrostatic chuck is H2 = 9.5 to 15 mm.

As shown in FIG. 8C, in step S3, the intake end of the micro-cylinder 101 stops inputting gas, the gas in the cylinder is exhausted from the outlet end, the piston 102 descends to the initial position, the ejector 104 descends to the initial position, and the top of the ejector 104 Below the bottom surface of wafer 1, the air intake end of the cylinder 201 stops inputting gas, the gas in the cylinder is exhausted from the air exit end, the cylinder piston 202 descends to the initial position, the jacking arm 203 and the plunger rod 204 descend to the initial position, and the miniature cylinder 101 descends To the initial position.

The invention has the following advantages:

1. The use of a miniature cylinder to achieve the first stage of the jacking process, the use of a miniature cylinder to adjust the jacking height and jacking speed, to obtain the same jacking time and jacking force, short stroke of the miniature cylinder, reasonable control of the miniature cylinder The amount of air intake can achieve a gentle and stable jacking process to prevent damage to the wafer;

2. The miniature cylinder is small in size and saves space. The use of multiple miniature cylinders for the first stage of jacking up, and the use of one cylinder for the second stage of jacking up are more flexible and reduce costs;

3. No helium is needed, avoiding the risk of wafer contamination.

Although the content of the present invention has been described in detail through the above-mentioned preferred embodiments, it should be recognized that the above description should not be considered as limiting the present invention. Various modifications and alternatives to the present invention will be apparent to those skilled in the art after reading the foregoing. Therefore, the protection scope of the present invention should be defined by the scope of the attached patent application.

1,406‧‧‧chip
101‧‧‧Mini Cylinder
102‧‧‧Piston
103‧‧‧Guide sleeve
104‧‧‧ Jack
1041‧‧‧ Main body
1042‧‧‧Sealing ring
105‧‧‧ Bellows
106‧‧‧Seal ring flange
107‧‧‧stop block
108‧‧‧thrust detector
109‧‧‧contact detector
2.404‧‧‧Electrostatic Chuck
201, 206‧‧‧ cylinder
202‧‧‧cylinder piston
203‧‧‧Lifting arm
204‧‧‧ plunger rod
205‧‧‧cylinder stop
21‧‧‧Guideway
3‧‧‧ equipment tray
301‧‧‧first piston
302‧‧‧Second Piston
305‧‧‧Second cylinder
311, 312‧‧‧ plug
442‧‧‧ strain gauge
450‧‧‧ Digital Signal Processor
452‧‧‧Motor controller

FIG. 1 is a schematic structural diagram of a jacking device in the prior art. Figures 2A to 2C are schematic structural diagrams of another jacking device in the prior art. FIG. 3 is a schematic structural diagram of a third jacking device in the prior art. FIG. 4 is a schematic structural diagram of a wafer lifting device provided by the present invention. Fig. 5 is a partially enlarged schematic diagram of the jacking element. Fig. 6 is a plan view of a wafer lifting device. FIG. 7 is a schematic structural diagram of a first jacking element. 8A to 8C are schematic diagrams of a wafer jacking method.

1‧‧‧Chip

101‧‧‧Mini Cylinder

102‧‧‧Piston

103‧‧‧Guide sleeve

104‧‧‧ Jack

1041‧‧‧ Main body

105‧‧‧ Bellows

106‧‧‧Seal ring flange

107‧‧‧stop block

2‧‧‧ electrostatic chuck

201‧‧‧ Cylinder

202‧‧‧cylinder piston

203‧‧‧Lifting arm

204‧‧‧ plunger rod

205‧‧‧cylinder stop

21‧‧‧Guideway

3‧‧‧ equipment tray

Claims (16)

A wafer lifting device is arranged in a plasma etching cavity. An equipment disk (3) is arranged in the etching cavity, an electrostatic chuck (2) is arranged on the equipment disk (3), the electrostatic chuck (2) and the The device tray (3) has a plurality of through holes, and the wafer (1) is adsorbed on the electrostatic chuck (2). The through holes on the device tray (3) and the through holes on the electrostatic chuck (2) form a guide. Channel (21), the wafer lifting device comprises: a plurality of first lifting elements, which are arranged below the wafer through the guide channel (21), for completing the first lifting stage, and lifting the wafer to Separated from the electrostatic chuck; and a second jacking element, which is mechanically connected to all the first jacking elements, and is used to complete the second jacking stage, and continues to jack the wafer to a set distance; wherein, the first The jacking assembly includes a micro-cylinder (101) and an ejector element connected to the micro-cylinder (101). The micro-cylinder (101) drives the ejector element to raise and lift the wafer by a piston (102); The two jacking elements include a cylinder (201) and a plurality of connecting elements connecting the cylinder (201) and the miniature cylinder (101). The cylinder (201) using a cylinder-piston (202) by the connecting element further driving the Mini cylinder (101) and the top of the plunger element the wafer raised a set distance. The wafer lifting device according to item 1 of the scope of patent application, wherein the micro-cylinder (101) is provided in a guide sleeve (103) to move up and down along the axial direction of the guide sleeve (103), and the guide sleeve ( 103) Fixedly disposed below each of the guide channels (21). The wafer lifting device according to item 2 of the scope of patent application, wherein the number of the first lifting components is three or more. The wafer lifting device according to item 1 of the scope of the patent application, wherein the miniature cylinder (101) is provided with a stopper (107), and the stopper (107) prevents the piston (102) from continuing to move upward. The wafer lifting device according to item 4 of the scope of patent application, wherein the setting position of the stopper (107) satisfies the following conditions: when the piston (102) is located at the initial position of the bottom of the miniature cylinder (101), the The distance between the bottom surface of the stop block (107) and the top surface of the piston (102) is H1 = 0.5 to 3 mm. The wafer lifting device according to item 2 of the patent application scope, wherein the ejector element is disposed in the guide channel (21), and the ejector element includes an ejector body (1041) and the ejector body The jack (104) in (1041), the bottom of the jack body (1041) is sealedly connected to the top of the miniature cylinder (101) by a bellows (105), and the jack (104) is sealed by a seal ring ( 1042) is embedded in the top of the ejector main body (1041), and the bottom of the ejector (104) is fixedly connected to the piston (102) of the miniature cylinder (101). Driven by the piston (102), the ejector (102) The rod (104) can be jacked up, and the top of the rod (104) contacts the wafer (1) and jacks the wafer (1). The wafer lifting device according to item 6 of the patent application scope, wherein the wafer lifting device further includes a control device, the control device includes: a plurality of thrust detectors (108), which are respectively disposed on the pistons (102) The bottom is used to detect the magnitude of the thrust. The number of the thrust detectors (108) is the same as the number of the first jacking components; a plurality of contact detectors (109) are arranged at the bottom of the wafer (1), respectively Above the ejector pin (104) is used to detect when the ejector pin (104) contacts the wafer, and the number of the contact detectors (109) is the same as the number of the first jacking component; the controller, its electrical properties The thrust detectors (108), the contact detectors (109), and the miniature cylinders (101) are connected, and the controller implements synchronous control of the plurality of first jacking elements to ensure each of the jacks The thrust force is the same, and the time that each ejector pin contacts the wafer is the same. The wafer lifting device according to item 1 of the scope of patent application, wherein the first lifting assembly further comprises: a seal ring flange (106), which is disposed between the equipment plate (3) and the guide sleeve (103) For isolation seals. The wafer lifting device according to item 1 of the scope of patent application, wherein the cylinder (201) is provided with a cylinder stop block (205), and the cylinder stop block (205) prevents the cylinder piston (202) from continuing to move upward . The wafer lifting device according to item 9 of the scope of the patent application, wherein the setting position of the cylinder stop block (205) satisfies the following conditions: when the cylinder piston (202) is located at the initial position of the bottom of the cylinder (201), The distance between the bottom surface of the cylinder stop block (205) and the top surface of the cylinder piston (202) is H2 = 9.5 to 15 mm. The wafer lifting device according to item 1 of the patent application scope, wherein the connecting element in the second lifting element includes: a plurality of lifting arms (203), each of which is fixedly connected to the cylinder The number of pistons (202), the lifting arms (203) is the same as the number of the first lifting components; a plurality of plunger rods (204), and the upper ends of each of the plunger rods (204) are correspondingly connected to the miniature cylinders At the bottom of (101), a lower end of each of the plunger rods (204) is fixedly connected to one of the lifting arms (203), and the number of the plunger rods (204) is the same as the number of the first lifting components. A wafer lifting method implemented by using a wafer lifting device according to any one of claims 1 to 11 of the scope of patent application, comprising the following steps: Step S1, using the first lifting element to complete the first In the jacking-up phase, the wafer is jacked up to 0.5 to 3 mm from the electrostatic chuck in the plasma-on state, so that the wafer is separated from the electrostatic chuck; the gas inlet of the micro-cylinder (101) is supplied with gas, and the piston ( 102) Drive the ejector pin (104) to rise upward. During the ejection process, the control device controls the air intake of the micro-cylinder (101) to control the same thrust of all ejectors and all the ejector contacts. The time of the wafer is the same. When the piston (102) contacts the stop block (107), it stops moving, the ejector rod (104) stops jacking up, and the current air intake of the miniature cylinder (101) is kept unchanged. Step S2, using the second jacking element to complete the second jacking stage, and continuing to jack the wafer to a distance of 9.5 to 15 mm from the electrostatic chuck in the plasma closed state; the air inlet end of the cylinder (201) Input gas, the cylinder piston (202) drives the plurality of tops The arm (203) moves upward, the lifting arm (203) drives the plunger rod (204) connected to it to move upward, and the plurality of plunger rods (204) respectively drive the micro cylinder (101) and the ejector rod (204) 104) Lift upward until the cylinder piston (202) contacts the cylinder stop (205), the cylinder piston (202) stops moving; and step S3, after the wafer is removed, the first jack The element and the second jacking element are lowered back to the initial position, and wait for the next jacking process. The wafer jacking method according to item 12 of the patent application scope, wherein the first jacking stage is performed in the plasma-on state. The wafer jacking method according to item 12 of the patent application scope, wherein the second jacking stage is performed in the plasma off state. The wafer lifting method according to item 12 of the scope of patent application, wherein the first lifting element and the second lifting element descend to the initial position and specifically include the following steps: the intake end of the micro-cylinder (101) is stopped The gas is input, the gas in the cylinder is discharged from the gas outlet, the piston (102) is lowered to the initial position, the ejector (104) is lowered to the initial position, and the top of the ejector (104) is lower than the bottom surface of the wafer (2). The intake side of the cylinder (201) stops inputting gas, and the gas in the cylinder is exhausted from the exhaust side. The cylinder piston (202) descends to the initial position, and the jacking arm (203) and the plunger rod (204) descend to the initial position. The miniature cylinder (101) descends to the initial position. A plasma etching device includes an etching cavity, an equipment disk (3) disposed in the etching cavity, an electrostatic chuck (2) disposed on the equipment disk (3), and a wafer being adsorbed on the electrostatic chuck. (2), the electrostatic chuck (2) and the equipment tray (3) each have a plurality of through holes, and the through holes on the equipment tray (3) and the through holes on the electrostatic chuck (2) form a guide Channel (21); The plasma etching device further includes a wafer lifting device disposed in a plasma etching chamber as described in any one of claims 1 to 11 of the scope of patent application.