阅读说明：本技术 晶圆晶边清洗装置及晶圆晶边清洗方法 (Wafer edge cleaning device and wafer edge cleaning method ) 是由 邢磊 于 2018-09-12 设计创作，主要内容包括：本发明提供一种晶圆晶边清洗装置及晶圆晶边清洗方法,清洗装置包括：晶圆卡盘；位置传感装置,设置于晶圆卡盘上,用于感测晶圆的边缘的至少三个边缘位置坐标；数据处理终端,用于接收各边缘位置坐标,并基于各边缘位置坐标换算出圆心位置坐标,继而将圆心位置坐标与晶圆卡盘中心的位置进行比对,以基于比对结果判断是否继续进行晶圆的晶边光刻胶清洗。本发明可以实时监测晶圆与晶圆卡盘之间的位置关系,判断晶圆是否发生偏移,及时发现缺陷并进行处理,从而在晶圆晶边清洗工艺之前及时调整晶圆的位置,保证在晶圆清理时具有精确的洗边宽度,提高洗边效果,改善了晶圆边缘脱落缺陷,提高产品性能及产品良率。(The invention provides a wafer edge cleaning device and a wafer edge cleaning method, wherein the cleaning device comprises: a wafer chuck; the position sensing device is arranged on the wafer chuck and used for sensing at least three edge position coordinates of the edge of the wafer; and the data processing terminal is used for receiving the edge position coordinates, converting the circle center position coordinates based on the edge position coordinates, comparing the circle center position coordinates with the position of the center of the wafer chuck, and judging whether to continue to clean the wafer edge photoresist of the wafer based on the comparison result. The invention can monitor the position relation between the wafer and the wafer chuck in real time, judge whether the wafer deviates or not, and timely find and process the defects, thereby timely adjusting the position of the wafer before the wafer edge cleaning process, ensuring the accurate edge cleaning width during the wafer cleaning process, improving the edge cleaning effect, improving the edge falling defect of the wafer, and improving the product performance and the product yield.)

1. A wafer edge cleaning device is used for cleaning edge photoresist of a wafer and is characterized by comprising:

the wafer chuck is used for bearing a wafer;

the wafer chuck comprises at least three position sensing devices arranged below the wafer and used for correspondingly sensing at least three edge position coordinates of the edge of the wafer relative to the center of the wafer chuck, wherein the edge position coordinates are used for determining circle center position coordinates of the circle center of the wafer relative to the center of the wafer chuck; and

and the data processing terminal is used for receiving the edge position coordinates, converting the center position coordinates of the wafer based on the edge position coordinates, comparing the center position coordinates of the wafer with the center position of the wafer chuck, and judging whether to continue to clean the wafer edge photoresist of the wafer based on the comparison result.

2. The wafer edge cleaning device as claimed in claim 1, wherein each of the position sensing devices is configured to correspondingly determine the edge position coordinates of the wafer, which are passed by a projection of a connecting line between each of the position sensing devices and the center of the wafer chuck on a plane where the wafer is located, and a sensing range of each of the position sensing devices is between-10 mm and 10 mm.

3. The wafer edge wafer cleaning device according to claim 1, wherein the position sensor comprises a photosensitive sensor, the photosensitive sensor comprises a light source and a photosensitive element, wherein the light source emits emission light which is irradiated onto the wafer and reflected onto the photosensitive element to obtain the edge position coordinate, an acute emission included angle is formed between the emission light and a plane where the wafer is located, an acute photosensitive included angle is formed between reflection light reflected from the wafer and the photosensitive element, and the acute emission included angle is 30-60 degrees; the acute photosensitive included angle is between 30 and 60 degrees.

4. The wafer edge wafer cleaning device according to claim 3, wherein the photosensor further comprises a light wave filter disposed on an outgoing light path of the light source for filtering out an infrared band in the emitted light from the light source; the wavelength of the emitted light is between 500nm and 700 nm.

5. The wafer edge cleaning device according to any one of claims 1 to 4, further comprising an exception handling device, wherein the exception handling device is connected to the data processing terminal, and the data processing terminal controls the exception handling device to perform alarm, wafer replacement or wafer placement position adjustment according to the comparison result of the data processing terminal.

6. A wafer edge cleaning method is characterized by comprising the following steps:

1) providing a wafer and placing the wafer on a wafer chuck;

2) sensing at least three edge position coordinates of the edge of the wafer relative to the center of the wafer chuck by using a position sensing device, wherein the edge position coordinates are used for determining circle center position coordinates of the circle center of the wafer relative to the center of the wafer chuck; and

3) transmitting each edge position coordinate obtained in the step 2) to a data processing terminal, converting the center position coordinate based on each edge position coordinate by the data processing terminal, and then comparing the center position coordinate with the position of the center of the wafer chuck to judge whether to continue to clean the wafer edge photoresist of the wafer.

7. The wafer edge cleaning method according to claim 6, wherein in step 2), the position sensing device is disposed below the wafer, and at least three position sensing devices are disposed, wherein each of the position sensing devices is configured to determine the edge position coordinates of the edge position of the wafer through which a projection of a connecting line between the position sensing device and the center of the wafer chuck on a plane where the wafer is located passes; the sensing range of each position sensing device is between-10 mm and 10 mm.

8. The wafer edge cleaning method as claimed in claim 7, wherein the number of the position sensing devices is four, and a coordinate system with the center of the wafer chuck as a coordinate origin is defined, and the step of converting the center position coordinates based on the edge position coordinates in step 2) comprises:

2-1) correspondingly acquiring four edge position coordinates by adopting the four position sensing devices respectively;

2-2) obtaining a first straight line through two of the edge position coordinates, obtaining a second straight line through the other two edge position coordinates, obtaining a first perpendicular bisector in the circle where the wafer is located based on the first straight line, and obtaining a second perpendicular bisector in the circle where the wafer is located based on the second straight line, wherein the first perpendicular bisector and the second perpendicular bisector both pass through the center of the circle where the wafer is located; and

2-3) obtaining the intersection point coordinates of the first perpendicular bisector and the second perpendicular bisector to obtain the center position coordinates of the wafer.

9. The wafer edge wafer cleaning method according to claim 8, wherein in step 2), the position sensor comprises a photosensitive sensor, the photosensitive sensor comprises a light source and a photosensitive element, wherein the light source emits a light beam to the wafer and reflects the light beam onto the photosensitive element to obtain the edge position coordinate, an acute angle emission included angle is formed between the light beam and a plane where the wafer is located, and an acute angle photosensitive included angle is formed between the light beam reflected from the wafer and the photosensitive element, and the acute angle emission included angle is 30-60 °; the acute photosensitive included angle is between 30 and 60 degrees; the light sensor also comprises an optical wave filter, wherein the optical wave filter is arranged on an emergent light path of the light source and is used for filtering out an infrared wave band in emitted light from the light source; the wavelength of the emitted light emitted by the light source is between 500nm-700 nm.

10. The wafer edge wafer cleaning method according to any one of claims 6 to 9, wherein the step of determining whether to continue the wafer edge photoresist cleaning based on the comparison result in step 3) comprises:

the data processing terminal compares the position coordinate of the center of the circle of the wafer with the position of the center of the wafer chuck, if the distance between the center of the circle of the wafer and the center of the wafer chuck is smaller than or equal to a set distance, the wafer edge photoresist cleaning process of the wafer is continued, and if the distance between the two points is larger than the set distance, the adjustment processing is carried out; the adjusting process is selected from at least one of the group consisting of controlling a machine platform device to give an alarm and stop to wait for processing, taking out the wafer by using a mechanical arm and placing the wafer in a buffer carrying disc to wait for processing, and controlling the mechanical arm to adjust the position of the wafer by the data processing terminal based on the comparison result so as to perform sensing comparison again.

11. The method as claimed in claim 10, wherein when the adjusting process adopts a manner that the data processing terminal controls a robot arm to adjust the position of the wafer based on the comparison result to perform sensing comparison again, the method includes the following specific steps:

a) controlling the mechanical arm to adjust the position of the wafer based on the comparison result;

b) sequentially repeating the step 2) and the step 3), if the distance between the circle center of the wafer and the center of the wafer chuck is smaller than or equal to the set distance, continuing to perform the wafer edge photoresist cleaning process of the wafer, and if the distance between the two points is larger than the set distance, performing the step c);

c) and sequentially repeating the step a) and the step b) until the distance between the circle center of the wafer and the center of the wafer chuck is smaller than or equal to the set distance.

12. The wafer edge cleaning method as claimed in claim 11, wherein in the step c), the step a) is repeated no more than twice, and if the distance between the center of the wafer and the center of the wafer chuck is still larger than the set distance after the step a) is repeated twice, the wafer is taken out by using a robot arm and placed in a buffer tray to wait for processing.

Technical Field

The invention belongs to the technical field of integrated circuit manufacturing, and particularly relates to a wafer edge cleaning device and a wafer edge cleaning method.

Background

In a semiconductor production process, a wafer is detected to be defective, most peeling defects appear on the edge of the wafer and form a circle, and in order to avoid the peeling of the edge of the wafer from producing hardness to the yield of products, the conventional method is to remove the peeling source by means of wafer edge cleaning.

Currently, for removing the photoresist on the Edge of the wafer, an Edge Bead removal process (EBR) is usually performed after the photoresist coating, and the general process of EBR is as follows: the edge-washing solvent is sprayed in an edge-washing area at the edge of the wafer through the nozzle to dissolve residual photoresist, in addition, in the EBR process, the width of the edge-washing needs to be set according to the process requirement, and in actual production, because the wafer deviates from the central position on an edge-washing machine, the actual edge-washing effect is inconsistent with the setting, and the yield and the performance of the product are influenced.

Therefore, it is necessary to provide a wafer edge cleaning apparatus and a wafer edge cleaning method to solve the above-mentioned problems in the prior art.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a wafer edge cleaning apparatus and a wafer edge cleaning method, which are used to solve the problems in the prior art that it is difficult to effectively monitor the position deviation during the wafer edge cleaning process, so that the defects cannot be found in time, and the product yield and performance are affected.

To achieve the above and other related objects, the present invention provides a wafer edge cleaning apparatus for cleaning edge photoresist of a wafer, including:

the wafer chuck is used for bearing a wafer;

the wafer chuck comprises at least three position sensing devices arranged below the wafer and used for correspondingly sensing at least three edge position coordinates of the edge of the wafer relative to the center of the wafer chuck, wherein the edge position coordinates are used for determining circle center position coordinates of the circle center of the wafer relative to the center of the wafer chuck; and

and the data processing terminal is used for receiving the edge position coordinates, converting the center position coordinates of the wafer based on the edge position coordinates, comparing the center position coordinates of the wafer with the center position of the wafer chuck, and judging whether to continue to clean the wafer edge photoresist of the wafer based on the comparison result.

As an alternative of the present invention, each of the position sensing devices is configured to determine the edge position coordinates of the edge position of the wafer, where a projection of a connecting line between each of the position sensing devices and the center of the wafer chuck on a plane where the wafer is located passes through, in correspondence with the edge position coordinates, and a sensing range of each of the position sensing devices is between-10 mm and 10 mm.

As an alternative of the present invention, the position sensing device includes a photosensitive sensor including a light source and a photosensitive element, wherein the light source emits a light to irradiate the wafer and reflect the light to the photosensitive element to obtain the edge position coordinates; an acute-angle emission included angle is formed between the emitted light and a plane where the wafer is located, and an acute-angle photosensitive included angle is formed between the reflected light reflected from the wafer and the photosensitive element, wherein the acute-angle emission included angle and the acute-angle photosensitive included angle are approximately the same, and the acute-angle emission included angle is between 30 degrees and 60 degrees; the acute photosensitive included angle is between 30 and 60 degrees.

As an alternative of the present invention, the light sensor further includes a light wave filter, disposed on an emergent light path of the light source, for filtering out an infrared band in the emitted light from the light source; the wavelength of the emitted light is between 500nm and 700 nm.

As an alternative of the invention, the wafer edge cleaning device further comprises an exception handling device, the exception handling device is connected to the data processing terminal, and the exception handling device performs alarming, wafer replacement or wafer placement position adjustment according to the comparison result of the data processing terminal.

The invention also provides a wafer edge cleaning method, which comprises the following steps:

1) providing a wafer and placing the wafer on a wafer chuck;

2) sensing at least three edge position coordinates of the edge of the wafer relative to the center of the wafer chuck by using a position sensing device, wherein the edge position coordinates are used for determining circle center position coordinates of the circle center of the wafer relative to the center of the wafer chuck; and

3) transmitting each edge position coordinate obtained in the step 2) to a data processing terminal, converting the center position coordinate based on each edge position coordinate by the data processing terminal, comparing the center position coordinate with the center position of the wafer chuck, and judging whether to continue to clean the wafer edge photoresist of the wafer based on the comparison result.

As an alternative of the present invention, in step 2), the position sensing device is disposed below the wafer, and at least three position sensing devices are disposed, where each of the position sensing devices is configured to correspondingly determine the edge position coordinates of the edge position of the wafer, where a projection of a connecting line between the position sensing device and the center of the wafer chuck on a plane where the wafer is located passes through; the sensing range of each position sensing device is between-10 mm and 10 mm.

As an alternative of the present invention, the number of the position sensing devices provided is four, and a coordinate system having the center of the wafer chuck as a coordinate origin is defined, wherein the step of converting the center position coordinates based on the edge position coordinates in step 2) includes:

2-1) correspondingly acquiring four edge position coordinates by adopting the four position sensing devices respectively;

2-2) obtaining a first straight line through two of the edge position coordinates, obtaining a second straight line through the other two edge position coordinates, obtaining a first perpendicular bisector in the circle where the wafer is located based on the first straight line, and obtaining a second perpendicular bisector in the circle where the wafer is located based on the second straight line, wherein the first perpendicular bisector and the second perpendicular bisector both pass through the center of the circle where the wafer is located; and

2-3) obtaining the intersection point coordinates of the first perpendicular bisector and the second perpendicular bisector to obtain the center position coordinates of the wafer.

As an alternative of the present invention, in step 2), the position sensing device includes a photosensitive sensor, the photosensitive sensor includes a light source and a photosensitive element, wherein the light source emits a light to irradiate the wafer and reflect the light to the photosensitive element to obtain the edge position coordinate; an acute-angle emission included angle is formed between the emitted light and a plane where the wafer is located, and an acute-angle photosensitive included angle is formed between the emitted light reflected from the wafer and the photosensitive element, wherein the acute-angle emission included angle and the acute-angle photosensitive included angle are approximately the same, and the acute-angle emission included angle is between 30 degrees and 60 degrees; the acute photosensitive included angle is between 30 and 60 degrees; the light sensor also comprises an optical wave filter, wherein the optical wave filter is arranged on an emergent light path of the light source and is used for filtering out an infrared wave band in emitted light from the light source; the wavelength of the emitted light emitted by the light source is between 500nm-700 nm.

As an alternative of the present invention, in step 3), the step of determining whether to continue the wafer edge photoresist cleaning of the wafer based on the comparison result includes:

the data processing terminal compares the position coordinates of the circle center of the wafer with the position of the center of the wafer chuck, if the distance between the circle center of the wafer and the center of the wafer chuck is smaller than or equal to a set distance, the wafer edge photoresist cleaning process of the wafer is continued, and if the distance between the two points is larger than the set distance, the adjustment processing is carried out; the adjusting process is selected from at least one of the group consisting of controlling a machine platform device to give an alarm and stop to wait for processing, taking out the wafer by using a mechanical arm and placing the wafer in a buffer carrying disc to wait for processing, and controlling the mechanical arm to adjust the position of the wafer by the data processing terminal based on the comparison result so as to perform sensing comparison again.

As an alternative of the present invention, when the adjusting process adopts a manner that the data processing terminal controls the robot arm to adjust the position of the wafer based on the comparison result so as to perform sensing comparison again, the specific steps include:

a) controlling the mechanical arm to adjust the position of the wafer based on the comparison result;

b) sequentially repeating the step 2) and the step 3), if the distance between the circle center of the wafer and the center of the wafer chuck is smaller than or equal to the set distance, continuing to perform the wafer edge photoresist cleaning process of the wafer, and if the distance between the two points is larger than the set distance, performing the step c);

c) and sequentially repeating the step a) and the step b) until the distance between the circle center of the wafer and the center of the wafer chuck is smaller than or equal to the set distance.

As an alternative of the present invention, in the step c), the number of times of repeating the step a) is not more than two, and if the distance between the center of the wafer and the center of the wafer chuck is still greater than the set distance after repeating the step a) twice, the wafer is taken out by using a robot arm and placed in a buffer tray to wait for processing.

As described above, the wafer edge cleaning apparatus and the wafer edge cleaning method according to the present invention have the following advantageous effects:

the wafer edge cleaning device and the wafer edge cleaning method provided by the invention can monitor the position relation between the wafer and the wafer chuck in real time, judge whether the wafer deviates or not, and timely find and process the defects, so that the position of the wafer can be timely adjusted before the wafer edge cleaning process, the accurate edge cleaning width is ensured during wafer cleaning, the edge cleaning effect is improved, the defect of wafer edge falling is improved, and the product performance and the product yield are improved.

Drawings

FIG. 1 is a schematic diagram illustrating wafer-to-wafer chuck misalignment during wafer edge cleaning in the prior art.

FIG. 2 is a schematic top view of a wafer edge cleaning apparatus according to the present invention.

Fig. 3 is a schematic structural diagram of a wafer chuck in the wafer edge cleaning apparatus according to the present invention.

Fig. 4 is a schematic diagram illustrating wafer edge cleaning performed by the wafer edge cleaning method according to the present invention.

Fig. 5 is a process flow chart of the wafer edge cleaning method according to the present invention.

Fig. 6 is a schematic diagram illustrating the edge position coordinates obtained in the wafer edge cleaning method according to the present invention.

Fig. 7 is a schematic diagram illustrating that the straight line k1 and the straight line k2 are obtained in the wafer edge cleaning method provided by the invention.

Fig. 8 is a schematic diagram illustrating the vertical bisectors k3 and k4 obtained in the wafer edge cleaning method provided by the present invention.

Fig. 9 is a schematic diagram illustrating the edge position coordinate acquisition of the photosensor in the wafer edge cleaning according to the present invention.

Fig. 10 is a schematic diagram illustrating the edge position coordinate acquisition of the photo sensor during wafer edge cleaning according to the present invention when the wafer is shifted.

FIG. 11 is a schematic diagram illustrating the effect of an IR-cut filter on the light absorption level in wafer edge cleaning according to the present invention.

Description of the element reference numerals

100 wafer

101 wafer chuck

200 wafer chuck

201 position sensing device

202 wafer chuck center

203 nozzle

300 wafer

301 center of wafer

400 photosensitive sensor

401 light source

402 photosensitive element

403 sensitive region

S1-S3 Steps 1) to 3)

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

Please refer to fig. 1 to 11. It should be noted that the drawings provided in the present embodiment are only schematic and illustrate the basic idea of the present invention, and although the drawings only show the components related to the present invention and are not drawn according to the number, shape and size of the components in actual implementation, the form, quantity and proportion of the components in actual implementation may be changed arbitrarily, and the layout of the components may be more complicated.

As shown in fig. 2-4, the present invention provides a wafer edge cleaning apparatus for cleaning edge photoresist of a wafer, including: wafer chuck 200, position sensing device 201 and data processing terminal, wherein:

for the wafer chuck (chuck)200, as shown in fig. 2 and 3, the wafer chuck 200 is used for carrying a wafer 300, for example, in a step of removing edge glue after a glue coating process in a cleaning process of a wafer edge, the wafer chuck 200 may be driven to rotate, and the edge glue cleaning apparatus starts to operate, at this time, as shown in fig. 4, the nozzle 203 is close to the wafer 300 and adjusts a position of the nozzle according to a set edge washing width, and when the position is appropriate, an edge washing solution is sprayed out from the nozzle 203 to perform a photoresist cleaning operation on the wafer edge, where the edge washing width refers to a width of the washed photoresist, that is, a distance from the wafer edge to a photoresist edge after edge washing, and the photoresist cleaning also refers to cleaning a source of peeling, so as to prevent peeling defects, where the peeling defects refer to PR peeling, which may occur in a developing process and a subsequent Etch (etching) process, thereby generating defect when Etch, the edge washing width is set according to practical situation, such as 0-2mm, such as 1mm, of course, a certain range of error, such as +0.3mm error relative to 1mm, can be accepted.

In addition, as for the position sensing device 201, it may be a position sensor, as shown in fig. 2, the position sensing device 201 is disposed below the wafer 300, in an example, the wafer chuck is smaller than the wafer, the position sensing device is preferably disposed on the wafer chuck 200, in an example, a fixing device may be fixed on the wafer chuck 200, so that space may be saved and work of other components may not be affected, in other examples, the position sensing device 201 may be disposed on the wafer chuck 200 in a mosaic manner. In the present invention, the position sensing device 201 is configured to sense at least three edge position coordinates of the wafer 300 relative to the center of the wafer chuck 200, so as to determine a center position coordinate of the center of the wafer relative to the center of the wafer chuck 200 based on the edge position coordinates, where the edge position coordinates refer to position coordinates of the edge of the wafer, so as to determine a position coordinate of the center of the wafer based on the coordinate position of the edge, where the edge position coordinates and the center position coordinates of the wafer refer to a same coordinate system, for example, a coordinate system using the center of the wafer chuck 200 as an origin of the coordinate system, and the center of the wafer refers to a center position of a circle where the wafer is located, that is, the center of the wafer.

In addition, the data processing terminal (not shown in the figure) may be a PC terminal, and is configured to receive each edge position coordinate, convert the circle center position coordinate of the wafer based on each edge position coordinate, and compare the circle center position coordinate with the position of the center of the wafer chuck to determine whether to continue the wafer edge photoresist cleaning of the wafer.

Specifically, after the position sensing device 201 detects the boundary position of the wafer, the boundary position is fed back to the data processing terminal (PC end), and the processing and comparison operations of the coordinate position data can be performed at the PC end, after the comparison, if the result after the comparison is within the actually set range, the edge washing process of the wafer can be continued, so that the wafer can be ensured to have a proper edge washing width, and if the comparison result is outside the set range, it indicates that the deviation of the wafer 300 relative to the wafer chuck 200 cannot be received, and at this time, the edge washing process of the wafer cannot be continued, and the edge washing process is performed after waiting for the operation of an engineer.

In addition, the wafer edge cleaning apparatus includes at least three position sensing devices 201 for correspondingly sensing at least three edge position coordinates of the edge of the wafer relative to the center of the wafer chuck, wherein in an optional example, a preset distance s is respectively provided between each position sensing device 201 and the center 202 of the wafer chuck, the preset distance s is only required to achieve the sensing of the edge position coordinates, in a preferred example, the size of each preset distance s is approximately the same, so that the measurement and the installation design can be facilitated, further, the preset distance s is not greater than the radius of the wafer, so that the position sensing devices can be installed on the wafer chuck smaller than the wafer, and the operation is facilitated.

As an example, the numerical size of the preset spacing s includes the size of the radius of the wafer 300.

Specifically, in an optional example, at least three sensing devices are provided, wherein each of the position sensing devices 201 correspondingly tests edge position coordinates of an edge of a wafer, and accordingly correspondingly feeds back the edge position coordinates to the data processing terminal, further, it is preferable to set the centers of the position sensing devices 201 relative to the wafer chuck 200 to be consistent, that is, the position sensing devices 201 are located on the same horizontal plane and have equal distances (the preset distances) from the wafer chuck center 202, and in a further preferred example, the value of the preset distance is set to be a radius value of the wafer, so that not only data feedback but also better operation can be facilitated, and comparison of coordinate positions can be facilitated.

As an example, each of the position sensing devices 201 is configured to determine the edge position coordinates of the edge position of the wafer 300, which are passed by the projection of the connection line between the position sensing device 201 and the wafer chuck center 202 on the plane where the wafer is located.

Specifically, the position sensing device 201 acquires a required edge position coordinate, in an example, the position sensing device 201 acquires an edge position coordinate on an edge of the wafer 300 at a position where a projection of a connecting line between the position sensing device and a center of the wafer chuck on a plane where the wafer is located passes, see M1, M2, M3, and M4 in fig. 6, so that the position sensing device can directly perform a test, and the position sensing device corresponds to the measured edge position coordinate one to one, thereby ensuring convenience and accuracy of the test.

In addition, in an example, referring to fig. 9 and 10, the position sensing apparatus 201 includes a photosensitive sensor 400, and the photosensitive sensor 400 includes a light source 401 and a photosensitive element 402, wherein the light source 401 emits a light to irradiate the wafer 300 and reflect the light to the photosensitive element 402 to obtain the edge position coordinates.

In particular, in this example, the position sensing means 201 is chosen as a light sensitive sensor 400, which may be a CCDSensor, may be a position sensing sensor as is well known in the art, in this example, the light source is integrated with the sensor in the same device, i.e. the light source 401 and the light sensitive element 402, may be integrated in the same device, as shown in figures 9 and 10, during the measurement process, the incident light is ensured to strike the wafer, the reflected light can return to the sensor to realize distance measurement, the emission angle of the light source is more than 0 degree and less than 90 degrees, preferably between 30 degrees and 60 degrees, the emission light emitted by the light source 401 can irradiate the surface of the wafer, the reflected light reflected by the wafer irradiates the photosensitive element 402, the edge position coordinate of the wafer is judged through the sensitivity area 403, wherein, the CCD Sensor senses the light receiving degree% of the Wafer boundary in the range of 0 to 100%. In addition, the position of the photosensitive sensor 400 can be determined according to actual conditions, in a preferred example, the photosensitive sensor 400 is located right below the wafer 300, that is, the projection of the center of the photosensitive sensor 400 is right on the edge of the wafer 300, and preferably the projection of the center of the photosensitive element 402 is right on the edge of the wafer 300, so as to be beneficial to practical application.

As an example, the emitted light and the plane of the wafer have an acute emission angle β therebetween, and the reflected light reflected from the wafer and the photosensitive element have an acute photosensitive angle δ therebetween, wherein the acute emission angle β and the acute photosensitive angle δ are substantially the same.

As an example, the acute included emission angle β is greater than 0 ° and less than 90 °, preferably between 30 ° and 60 °, and preferably 45 ° in this example, and the acute included sensitization angle δ is greater than 0 ° and less than 90 °, preferably between 30 ° and 60 °, and preferably 45 ° in this example, wherein "between …" in this document refers to a range of values inclusive.

By way of example, each of the position sensing devices 201 has a sensing range between-10 mm and 10mm, preferably between-8 mm and 8mm, wherein the sensing range refers to an effective range that can be sensed by a sensor, and the meaning of-10 mm and 10mm here refers to the meaning of two symmetrical directions with respect to the position sensing device 201 itself.

Specifically, as shown in fig. 9, an acute emission angle β is defined for the photo sensor 400, wherein an angle α of CCDSensor, that is, a light receiving angle of a sensor, an angle of incident light relative to a surface of a wafer is equal to the acute emission angle β, and in a preferred example, the acute emission angle β is substantially the same as the acute photo angle δ, that is, it is preferable to ensure that a photo sensing surface of the photo sensing element 402 is parallel to a plane where the surface of the wafer 300 is located, so that the test accuracy can be further ensured.

In one example, the light sensor further includes a light wave filter (not shown) disposed on an outgoing light path of the light source for filtering out an infrared band in the emitted light from the light source.

As an example, the light source emits emitted light having a wavelength between 500nm and 700 nm.

Specifically, the optical wave filter is disposed on an outgoing light path of the light source, that is, a light path between the light source and the wafer or a light path between the light source and the photosensitive element, in an example, the optical wave filter includes an infrared cut filter, the infrared cut filter is disposed on the photosensitive element 402, and is used for obtaining excellent emitted light and improving the absorption degree of the photosensitive element to the light, and the optical wave filter is preferably disposed on a photosensitive surface of the photosensitive element, in an example, the wavelength of the emitted light emitted by the light source 401 is between 500nm and 700nm, and is preferably 600nm, as shown in fig. 11, when the incident light of the wavelength band is selected, the absorption degree to the light finally approaches 100% when the infrared cut filter is present.

As an example, the wafer edge cleaning device further includes an exception handling device, the exception handling device is connected to the data processing terminal, and the data processing terminal controls the exception handling device to perform alarm, wafer replacement, or wafer placement position adjustment according to the comparison result of the data processing terminal.

Specifically, the wafer edge cleaning device further comprises an exception handling device connected with the data processing terminal, the exception handling device makes a corresponding response according to the comparison result of the data processing terminal, and the response includes at least one of alarming, sending a wafer replacement instruction and sending a wafer square position adjustment instruction, in one example, if the distance between the center of the wafer and the center of the wafer chuck is greater than a set distance, the exception handling device may send an alarm signal to alarm to remind an operator of next processing, or the distance between the center of the wafer and the center of the wafer chuck is greater than the set distance, the exception handling device controls a machine equipment to send an alarm and stop to wait for processing; in another example, when the distance between the center of the wafer and the center of the wafer chuck is greater than a set distance, the exception handling device controls the robot arm to perform wafer replacement, that is, controls the robot arm to take out the wafer and place the wafer in a buffer tray to wait for processing, where the robot arm may be a robot arm provided in a machine station itself or a robot arm in the exception handling device; in another example, when the distance between the center of the wafer and the center of the wafer chuck is greater than a set distance, the abnormality processing device controls the robot arm to adjust the wafer placement position, that is, controls the robot arm to move the wafer, and further, after the wafer moves, controls the data processing terminal to perform sensing comparison, so that the final wafer is adjusted to a proper position, where the robot arm may be a robot arm provided in a machine station itself or a robot arm in the abnormality processing device.

It should be noted that, this embodiment provides a wafer edge cleaning apparatus, based on the apparatus, first place a wafer on the wafer chuck of the apparatus, then use the set position sensing apparatus to obtain edge position coordinates, transmit the obtained coordinates to the data processing terminal, perform conversion comparison, and then guide the wafer edge cleaning process based on the conversion comparison result, that is, in any existing wafer edge cleaning apparatus, the problem of poor wafer edge cleaning effect can be solved by the position sensing apparatus and the data processing terminal of the present invention, the wafer edge cleaning apparatus of the present invention can monitor the position relationship between the wafer and the wafer chuck in real time, determine whether the wafer is deviated, find defects and process in time, adjust the position of the wafer in time before the wafer edge cleaning process, the wafer cleaning device has the advantages that the accurate edge cleaning width is ensured during wafer cleaning, the edge cleaning effect is improved, the defect of wafer edge falling is overcome, and the product performance and yield are improved.

As shown in fig. 5, the present invention further provides a wafer edge cleaning method, wherein the wafer edge cleaning method is preferably completed by using the wafer edge cleaning apparatus of the present invention, and the wafer edge cleaning method includes the following steps:

1) providing a wafer and placing the wafer on a wafer chuck;

2) sensing at least three edge position coordinates of the edge of the wafer relative to the center of the wafer chuck by using a position sensing device, wherein the edge position coordinates are used for determining circle center position coordinates of the circle center of the wafer relative to the center of the wafer chuck; and

3) transmitting each edge position coordinate obtained in the step 2) to a data processing terminal, converting the center position coordinate based on each edge position coordinate by the data processing terminal, comparing the center position coordinate with the center position of the wafer chuck, and judging whether to continue to clean the wafer edge photoresist of the wafer based on the comparison result.

The steps of the wafer edge cleaning method according to the present invention will be described in detail with reference to the accompanying drawings.

First, as shown in S1 in fig. 5 and fig. 6, step 1) is performed to provide a wafer 300, and the wafer is placed on a wafer chuck 200, wherein the wafer after being coated with glue may be placed on the wafer chuck 200 by using a robot ARM (ARM) to wait for wafer edge cleaning, and preferably, the wafer edge cleaning apparatus provided in this embodiment may be used, see fig. 3 and fig. 4;

next, as shown in S2 of fig. 5 and fig. 6, step 2) is performed, and the position sensing device 201 is used to sense at least three edge position coordinates (M1, M2, M3, M4) of the wafer 300 relative to the wafer chuck center 202, so as to determine a circle center position coordinate N of the wafer circle center 301 relative to the wafer chuck center 202 based on the edge position coordinates (M1, M2, M3, M4).

As an example, in step 2), at least three position sensing devices 201 are provided, the position sensing devices 201 are disposed below the wafer 300, in one example, the wafer chuck is smaller than the wafer, the position sensing devices are preferably disposed on the wafer chuck 200, and each position sensing device 201 measures the edge position coordinates of the edge position of the wafer 300 where a connecting line between the position sensing device 201 and the center 202 of the wafer chuck passes.

Specifically, in this step, the position sensing device 201 acquires the required edge position coordinates, in an example, the position sensing device 201 acquires the edge position coordinates on the edge of the wafer 300 at the position where the position sensing device is connected with the center of the wafer chuck, such as M1, M2, M3 and M4 in fig. 6, so that the position sensing device can be directly tested, and the position sensing device corresponds to the measured edge position coordinates one to one, thereby ensuring the convenience and accuracy of the test.

As an example, each of the position sensing devices 201 has a predetermined distance s from the center 202 of the wafer chuck 200, and the predetermined distance s is only required to realize the sensing of the edge position coordinates, and in a preferred example, the predetermined distances s are substantially the same in size, so that the measurement and installation design can be facilitated, and further, the predetermined distance s is not larger than the radius of the wafer, so that the position sensing devices can be installed on the wafer chuck smaller than the wafer, thereby facilitating the operation.

As an example, the size of the preset spacing s includes the size of the radius of the wafer.

Specifically, in an example, the position sensing device 201 is designed, wherein the position of the position sensing device (Sensor)201 is consistent with the center of the wafer chuck 200, that is, has the same preset distance s, for example, the preset distance s can be simultaneously disposed on the edge of the wafer chuck 200 with the same distance, and in a preferred example, the preset distance s is selected as the radius of the wafer, so that not only the feedback of data but also better operation can be facilitated, and the comparison of the coordinate positions can be facilitated.

As shown in fig. 6 to 8, an example is provided in which the number of the position sensing devices 201 is four, wherein the step of defining a coordinate system with the center of the wafer chuck 200 as the origin of coordinates and determining the center position coordinates (N) of the wafer center based on the edge position coordinates (M1, M2, M3, M4) comprises:

firstly, performing step 2-1), acquiring four edge position coordinates m1(x1, y1), m2(x2, y2), m3(x3, y3) and m4(x4, y4) by using four position sensing devices 201, and correspondingly acquiring edge position coordinates of each boundary point by using the position sensing devices in the step, as shown in fig. 6, wherein the wafer 300 is already obviously deviated from the center of the wafer chuck 200, and the wafer center 301 is not coincident with the wafer chuck center 202;

next, performing step 2-2), as shown in fig. 7, making a first straight line k1 through m1 and m2, making a second straight line k2 through m3 and m4, obtaining a first perpendicular bisector k3 in the circle where the wafer is located based on the first straight line k1, and obtaining a second perpendicular bisector k4 in the circle where the wafer is located based on the second straight line k2, where the first perpendicular bisector k3 and the second perpendicular bisector k4 both pass through the center of the circle where the wafer is located;

specifically, in this step, the coordinates of each edge position are known, so that in a coordinate system with the center 202 of the wafer chuck 200 as the origin of coordinates, a straight line equation passing through any two points therein can be obtained, as shown in fig. 7, such as a first straight line k1 passing through m1 and m2 points, for example, y1 ═ a1 × 1+ z1, where a1 and z1 are constants of straight lines; a second line k2 can be obtained that passes through points m3 and m4, such as y2 ═ a2 × 2+ z2, where a2 and z2 are constants of the lines. Then, in the plane of the coordinate system, the coordinates of the point k1, m1 and m2 are known to obtain an equation of a straight line k3 where the first perpendicular bisector of the segment m1m2 is located, y3 is a3 x3+ z3, where a3 and z3 are constants of the straight line, and similarly, an equation of a straight line k4 where the second perpendicular bisector of the segment m3m4 is located, y4 is a4 x4+ z4, where a4 and z4 are constants of the straight line, as shown in fig. 8. In this example, four edge position coordinates are taken as an example, and certainly, three edge position coordinates may be selected, in this case, one edge position coordinate of the three coordinates is shared when two straight lines are defined, and in addition, six or eight edge position coordinates may be selected in order to further ensure the accuracy of measuring the center position of the wafer circle.

Finally, as shown in fig. 8, performing step 2-3) to obtain the coordinates of the center of the circle based on the intersection point of the first perpendicular bisector y3 and the second perpendicular bisector y4, and as shown in fig. 8, obtaining a center position N (x5, y5) as the center position of the wafer 300 that is shifted according to the intersection point of the straight line k3/k 4.

In addition, in an example, as shown in fig. 9 to 11, an obtaining manner of the edge position coordinates (M1, M2, M3, M4) is provided, in step 2), the position sensing apparatus 200 includes a photosensitive sensor 400, the photosensitive sensor includes a light source 401 and a photosensitive element 402, wherein the light emitted by the light source 401 is irradiated onto the wafer 300 and reflected onto the photosensitive element 402 to obtain the edge position coordinates.

Specifically, in this example, the position sensing device 201 is selected as the photo Sensor 400, which may be a CCDSensor, the light source and the Sensor are integrated on the same device, that is, the light source 401 and the photo Sensor 402 may be integrated on the same device, as shown in fig. 9 and 10, during the measurement process, it is ensured that incident light hits on the Wafer, reflected light can return to the Sensor to achieve distance measurement, the emission angle of the light source is greater than 0 ° and less than 90 °, and preferably between 30 ° and 60 °, the emission light emitted by the light source 401 irradiates on the surface of the Wafer, the reflected light reflected by the Wafer irradiates on the photo Sensor 402, and the edge position coordinate of the Wafer is determined by the sensitivity region 403, wherein the range of the CCD Sensor sensing the% of the light receiving degree of the Wafer boundary is between 0% and 100%. In addition, the position of the photosensitive sensor 400 can be determined according to actual conditions, in a preferred example, the photosensitive sensor 400 is located right below the wafer 300, that is, the projection of the center of the photosensitive sensor 400 is right on the edge of the wafer 300, and preferably the projection of the center of the photosensitive element 402 is right on the edge of the wafer 300, so as to be beneficial to practical application.

By way of example, the emitted light from the light source 401 has an acute emission angle β with respect to the plane of the wafer 300, and the reflected light reflected from the wafer 300 has an acute photosensitive angle δ with respect to the photosensitive element 402, wherein the acute emission angle β is substantially the same as the acute photosensitive angle δ, and as an example, the acute emission angle β is greater than 0 ° and less than 90 °, preferably between 30 ° and 60 °, and in this example, is preferably 45 °, and the acute photosensitive angle δ is greater than 0 ° and less than 90 °, preferably between 30 ° and 60 °, and in this example, is preferably 45 °.

By way of example, the sensing range of the position sensor device 200 is between-10 mm and 10mm, preferably between-8 mm and 8mm, wherein the sensing range refers to the effective range that can be sensed by the sensor, and the meaning of-10 mm and 10mm here refers to the meaning of two symmetrical directions with respect to the position sensor device 201 itself.

Specifically, as shown in fig. 9, an acute emission angle β is defined for the photosensor 400, wherein an angle α of CCDSensor, i.e., a light receiving angle of a sensor, an angle of incident light relative to a surface of a wafer is equal to the acute emission angle β, and in a preferred example, the acute emission angle β is substantially the same as the acute light receiving angle δ, i.e., it is preferable to ensure that a light receiving surface of the photosensitive element 402 is parallel to a plane of the surface of the wafer, so as to further ensure the accuracy of the test, in addition, as shown in fig. 10, a change of light receiving condition when the wafer is shifted is shown, such as showing three positions of the wafer, when the middle wafer is shifted to the left, a light receiving area on the photosensitive element 402 is reduced, so as to sense the shift of the position, wherein, in an example, the acute emission angle β ° to 60 °, the acute light receiving angle δ is between 30 ° to 60 °, and a sensing range of the position sensing device 201 is between-10 mm to-10 mm, so as to further ensure the effectiveness of the wafer shift in the present invention.

As an example, in step 2), the position sensing device 201 includes a photosensitive sensor, wherein the step of filtering an infrared band in the emitted light of the photosensitive sensor is further included in the process of acquiring the edge position coordinates by using the photosensitive sensor.

In one example, if the photosensitive sensor is used to obtain the edge position coordinates in step 2), in a preferred example, the method further includes a step of filtering light emitted by the photosensitive sensor in an infrared band, and in one example, the photosensitive sensor further includes a light wave filter (not shown in the figure) disposed on an outgoing light path of the light source and configured to filter out the infrared band in the emitted light from the light source.

As an example, the light source 401 emits emission light having a wavelength between 500nm and 700 nm;

specifically, in one example, the optical wave filter is disposed on the light path emitted from the light source, i.e., the light path between the light source and the wafer or the light path between the light source and the photosensitive element, in one example, the optical wave filter includes an infrared cut filter disposed on the photosensitive element 402 for obtaining excellent emitted light and improving the light absorption degree of the photosensitive element, and the infrared cut filter is preferably disposed on the photosensitive surface of the photosensitive element, and in one example, the wavelength of the emitted light emitted from the light source 401 is between 500nm and 700nm, and is preferably 600nm, as shown in fig. 11, when the incident light of the wavelength band is selected, the light absorption degree of the light finally approaches 100% when the infrared cut filter is present.

In addition, in an example, in step 3), the step of determining whether to continue the wafer edge photoresist cleaning of the wafer based on the comparison result includes:

referring to fig. 6, the data processing terminal compares the circle center position coordinate 301 with the position of the wafer chuck center 202, if the distance between the circle center of the wafer and the center of the wafer chuck is smaller than or equal to a set distance, the wafer edge photoresist cleaning process of the wafer is continued, and if the distance between the two points is larger than the set distance, the adjustment process is performed; the adjusting process is selected from at least one of the group consisting of controlling a machine platform device to give an alarm and stop to wait for processing, taking out the wafer by using a mechanical arm and placing the wafer in a buffer carrying disc to wait for processing, and controlling the mechanical arm to adjust the position of the wafer by the data processing terminal based on the comparison result so as to perform sensing comparison again. In an example, the adjustment processing process may be performed based on the abnormality processing apparatus in the present embodiment.

Specifically, in this example, a position comparison method is provided, in which a center position (coordinate N is obtained) of the wafer is compared with a center of the wafer chuck, and a set distance is set according to actual requirements, where when a distance between two points is within a range of the set distance, it indicates that an error is within a permissible range, a process of cleaning a wafer edge photoresist of the wafer may be performed, that is, EBR is performed normally, where in one example, Spec is set to (0, ± 0.5mm), and the set distance is less than or equal to 0.5mm, which indicates that subsequent cleaning may be performed, and if the distance between two points is greater than the set distance, adjustment is required.

In addition, as an example, when the adjustment processing adopts a manner that the data processing terminal controls the robot arm to adjust the position of the wafer based on the comparison result so as to perform sensing comparison again, the specific steps include:

a) controlling the mechanical arm to adjust the position of the wafer based on the comparison result;

b) sequentially repeating the step 2) and the step 3), if the distance between the circle center of the wafer and the center of the wafer chuck is smaller than or equal to the set distance, continuing to perform the wafer edge photoresist cleaning process of the wafer, and if the distance between the two points is larger than the set distance, performing the step c);

c) and sequentially repeating the step a) and the step b) until the distance between the circle center of the wafer and the center of the wafer chuck is smaller than or equal to the set distance.

As an example, in the step c), the number of times of repeating the step a) is not more than two, and if the distance between the center of the wafer and the center of the wafer chuck is still larger than the set distance after repeating the step a) twice, the wafer is taken out by using a robot arm and placed in a buffer tray to wait for processing.

That is, the position of the wafer is adjusted by controlling the mechanical arm until the distance between the circle center and the center of the wafer chuck is less than or equal to the set distance, the adjustment times are less than or equal to 3 times, and the wafer is not qualified after exceeding 3 times, and the wafer is taken out by adopting the mechanical arm and is placed in a buffer loading disc to wait for processing.

In an alternative example, three processing manners beyond the set distance range are provided:

the equipment of the machine station is controlled to send the Alarm, the equipment stops and waits for the treatment of an engineer; the Wafer (Wafer) with the offset can be removed by controlling a mechanical Arm (Arm), and the Wafer (Wafer) is placed in a Buffer tray (Buffer) of a machine station, and the machine station carries out the next Wafer (Wafer) operation, and in addition, the wafers stored in the Buffer can be processed by engineers in a unified way; the data processing terminal (PC) may control the robot Arm (Arm) to place the wafer at the wafer placing position according to the position information detected by the position sensing device (Sensor), and reposition the wafer, and in a preferred example, the data processing terminal controls the robot Arm to reposition and then performs the operations of step 1) to step 3) of the present invention, and if the wafer is still unqualified, the wafer may be repositioned, and in a preferred example, the wafer may be repeated for 3 times, that is, the number of repetitions may be 1, 2, or 3 times, and if the wafer (position after repositioning is qualified), the EBR is normally performed; if the Spec out is still (the position still exceeds the allowable error range after the relocation), the Wafer is placed in a Buffer of the machine, and the machine performs the next Wafer (Wafer) operation, thereby ensuring the working efficiency of the machine.

In summary, the present invention provides a wafer edge cleaning apparatus and a wafer edge cleaning method, wherein the cleaning apparatus includes: the wafer chuck is used for bearing a wafer; the position sensing device is arranged on the wafer chuck and used for sensing at least three edge position coordinates of the edge of the wafer relative to the center of the wafer chuck, wherein the edge position coordinates are used for determining the circle center position coordinates of the circle center of the wafer relative to the center of the wafer chuck; and the data processing terminal is used for receiving the edge position coordinates, converting the circle center position coordinates based on the edge position coordinates, comparing the circle center position coordinates with the position of the center of the wafer chuck, and judging whether to continue to clean the wafer edge photoresist of the wafer based on the comparison result. By the scheme, the wafer edge cleaning device and the wafer edge cleaning method provided by the invention can monitor the position relation between the wafer and the wafer chuck in real time, judge whether the wafer deviates or not, find the defect in time and process the defect, so that the position of the wafer can be adjusted in time before the wafer edge cleaning process, the accurate edge cleaning width is ensured during wafer cleaning, the edge cleaning effect is improved, the defect of wafer edge falling is improved, and the product performance and the product yield are improved. Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.