Device and method for collecting metal on surface of silicon wafer

Abstract

The invention provides a silicon wafer surface metal collecting device and method, and belongs to the technical field of semiconductor manufacturing. The device comprises a sampling pipeline, a contact angle tester and a driving mechanism, a suction nozzle at one end of the sampling pipeline sucks scanning liquid with a set volume through a first suction hole and a second suction hole, and the scanning liquid is suspended in the suction nozzle to collect metal ions on the surface of a silicon wafer to be tested; the contact angle tester is arranged on the sampling pipeline, and a signal monitoring area of the contact angle tester is arranged around the suction nozzle; the driving mechanism is used for driving the sampling pipeline to lift according to the contact angle collected by the contact angle tester. Through real-time feedback of the contact angle and dynamic regulation and control of the driving mechanism on the position of the sampling pipeline, silicon wafers with different characteristics and surface forms of different positions of the same silicon wafer can be adapted, the loss of scanning liquid is effectively reduced, and the contact area of the scanning liquid and the surface of the to-be-detected silicon wafer is increased, so that the recovery rate of metal on the surface of the silicon wafer is improved, and the detection accuracy is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor manufacturing, and in particular to a silicon wafer surface metal collection device and method. BACKGROUND

[0002] With the rapid development of semiconductor manufacturing technology, the requirements for chip manufacturing are also increasing. In the process of manufacturing chips, metal contamination may occur on the surface of the silicon wafer. If the contaminated silicon wafer is not detected in time, the entire production line may be contaminated, which greatly affects the product quality. Therefore, it is particularly important to detect the metal on the surface of the silicon wafer.

[0003] Currently, when detecting the metal on the surface of the silicon wafer, the surface of the silicon wafer usually needs to be collected for metal. The collection method is generally as follows: a nozzle is used to suck scanning liquid, and the scanning liquid is moved on the surface of the silicon wafer to collect the metal solution, and then the metal contamination is detected on an inductively coupled plasma mass spectrometer (ICP-MS). However, different silicon wafers may have different thicknesses, different hydrophilic and hydrophobic properties, and even the same silicon wafer may have different surface flatness. In the existing silicon wafer surface metal collection process, when facing the differences in the surface of the silicon wafer, the scanning liquid is prone to fall off and the recovery rate of the metal on the surface of the silicon wafer is low, resulting in poor detection accuracy. SUMMARY

[0004] To solve the above technical problems, the present application provides a silicon wafer surface metal collection device and method, which can improve the recovery rate of the metal on the surface of the silicon wafer and thus improve the detection accuracy.

[0005] To achieve the above purpose, the technical solution adopted by the embodiments of the present application is as follows:

[0006] The embodiments of the present application provide a silicon wafer surface metal collection device, which comprises:

[0007] A sampling pipeline, one end of the sampling pipeline is provided with a nozzle, the sampling pipeline comprises a first sleeve and a second sleeve, the first sleeve is sleeved in the second sleeve, the end of the first sleeve is a first air inlet, and the end of the first sleeve and the end of the second sleeve are connected through an arc-shaped plate, the arc-shaped plate is provided with a second air inlet, the nozzle sucks a certain volume of scanning liquid through the first air inlet and the second air inlet, and the scanning liquid is suspended in the nozzle to collect metal ions on the surface of the silicon wafer to be detected;

[0008] a contact angle tester arranged on the sampling pipe and having a signal monitoring area of the contact angle tester arranged around the suction nozzle, the contact angle tester being configured to collect a contact angle between the scanning liquid and the silicon wafer to be tested;

[0009] a driving mechanism configured to drive the sampling pipe to move up and down according to the contact angle between the scanning liquid and the silicon wafer to be tested collected by the contact angle tester.

[0010] In some embodiments, a plurality of the sampling pipes are arranged side by side along a radius of the silicon wafer to be tested.

[0011] In some embodiments, the device further comprises:

[0012] a first pressure regulator arranged in the first sleeve to adjust a suction force of the first suction hole;

[0013] a second pressure regulator arranged in the second sleeve to adjust a suction force of the second suction hole.

[0014] The embodiments of the present application also provide a method for collecting metal on a surface of a silicon wafer, which is applied to the device for collecting metal on a surface of a silicon wafer and comprises the following steps:

[0015] adjusting a suction force of the suction nozzle to suck the scanning liquid to the suction nozzle and drive the sampling pipe to suspend the scanning liquid on the surface of the silicon wafer to be tested by the driving mechanism;

[0016] In the process of collecting metal ions on the surface of the silicon wafer to be tested by the scanning liquid, the contact angle tester collects a contact angle between the scanning liquid and the silicon wafer to be tested to obtain a first contact angle corresponding to a first contact position on the silicon wafer to be tested, the first contact position being any position on the surface of the silicon wafer to be tested;

[0017] In the case that the first contact angle is smaller than a second contact angle, the sampling pipe is driven to move towards the silicon wafer to be tested with the scanning liquid until the first contact angle reaches the second contact angle, the second contact angle being a preset contact angle determined according to the silicon wafer to be tested.

[0018] In some embodiments, before the sampling pipe is driven to move towards the silicon wafer to be tested with the scanning liquid until the first contact angle reaches the second contact angle, the method further comprises:

[0019] obtaining first parameter information of the silicon wafer, the first parameter information including a silicon wafer thickness and silicon wafer surface state information, the silicon wafer surface state information including hydrophilicity, hydrophobicity and roughness;

[0020] The second contact angle is determined according to the first parameter information and priori data, where the priori data includes parameter information of sample silicon wafers and preset contact angles corresponding to the sample silicon wafers.

[0021] In some embodiments, during the process of collecting metal ions on the surface of the silicon wafer to be tested by the scanning liquid, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested to obtain a first contact angle corresponding to a first contact position on the silicon wafer to be tested, including:

[0022] The contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested with the scanning liquid scanning a preset distance on the surface of the silicon wafer to be tested as a period, and obtains a first contact angle corresponding to a first contact position on the silicon wafer to be tested.

[0023] In some embodiments, during the process of collecting metal ions on the surface of the silicon wafer to be tested by the scanning liquid, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested to obtain a first contact angle corresponding to a first contact position on the silicon wafer to be tested, including:

[0024] Performing a flatness test on the surface of the silicon wafer to be tested to obtain a test result;

[0025] When the detection result indicates that the difference between the flatness of the first surface and the flatness of the second surface exceeds a preset threshold, when the scanning liquid scans to the first contact position on the surface of the silicon wafer to be tested, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested to obtain a first contact angle corresponding to the first contact position on the silicon wafer to be tested;

[0026] The first surface flatness is the surface flatness at the first contact position of the silicon wafer to be tested, and the second surface flatness is the surface flatness at the second contact position of the silicon wafer to be tested, where the second contact position is the upper position adjacent to the first contact position.

[0027] In some embodiments, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested to obtain a first contact angle corresponding to a first contact position on the silicon wafer to be tested, including:

[0028] The contact angle tester collects a plurality of contact angles between the scanning liquid and the silicon wafer to be tested, wherein the plurality of contact angles are contact angles collected around the first contact position;

[0029] The smallest contact angle among the plurality of contact angles is determined as the first contact angle.

[0030] In some embodiments, the method further comprises:

[0031] In some embodiments, the method further comprises:

[0032] In some embodiments, the method further comprises:

[0033] In some embodiments, the method further comprises:

[0034] In some embodiments, the second contact angle is greater than or equal to 90 degrees.

[0035] The present application has the following advantages:

[0036] In the present embodiment, the sampling pipeline adopts a double-sleeve structure of a first sleeve sleeved on a second sleeve, and the end portions are connected by an arc-shaped plate. The first air inlet at the end portion of the first sleeve and the second air inlet on the arc-shaped plate work together to enable the suction nozzle to form double negative pressure adsorption of the scanning liquid, thereby improving the adsorption force of the suction nozzle on the scanning liquid. When the scanning liquid is suspended in the suction nozzle to collect metal ions on the surface of the silicon wafer to be tested, the situation of the scanning liquid falling due to gravity, uneven surface tension, or contact pressure change is effectively reduced. In addition, a contact angle tester is arranged on the sampling pipeline to collect the contact angle between the scanning liquid and the silicon wafer to be tested. The spreading state of the scanning liquid on different surfaces of the silicon wafer or on different surfaces of the same silicon wafer can be determined through the contact angle. The driving mechanism dynamically adjusts the position of the sampling pipeline according to the contact angle, so that the scanning liquid maintains a droplet shape that fully contacts the surface of the silicon wafer to be tested. In this way, through the real-time feedback of the contact angle and the dynamic adjustment of the position of the sampling pipeline by the driving mechanism, the silicon wafer surface metal collection device provided by the present application can adapt to silicon wafers with different characteristics and the surface morphology of different positions of the same silicon wafer, effectively reducing the loss of the scanning liquid, increasing the contact area between the scanning liquid and the surface of the silicon wafer to be tested, thereby improving the recovery rate of the metal on the surface of the silicon wafer and improving the detection accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 FIG. 1 shows a structural schematic diagram of a silicon wafer surface metal collection device according to an embodiment of the present application;

[0038] Figure 2 FIG. 2 shows a structural schematic diagram of a suction nozzle of a silicon wafer surface metal collection device according to an embodiment of the present application;

[0039] Figure 3 Fig. 8 shows a schematic diagram of the contact angle between the scanning liquid and the silicon wafer in the embodiment of the present application;

[0040] Figure 4 Fig. 9 shows a schematic diagram of the structure of the silicon wafer surface metal collection device in the embodiment of the present application;

[0041] Figure 5 Fig. 10 shows a flow chart of the silicon wafer surface metal collection method in the embodiment of the present application. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by those skilled in the art belong to the scope of protection of the present application.

[0043] Different silicon wafers may have different thicknesses, and there are differences in hydrophilicity and hydrophobicity. Even the same silicon wafer may have different surface flatness. In the existing silicon wafer surface metal collection process, when facing the differences in the surface of the silicon wafer, the scanning liquid is prone to falling off and has a low silicon wafer surface metal recovery rate, resulting in poor detection accuracy.

[0044] The present application provides a silicon wafer surface metal collection device and method, which can improve the silicon wafer surface metal recovery rate and thus improve the detection accuracy.

[0045] The embodiments of the present application provide a silicon wafer surface metal collection device, as shown in Figure 1 and Figure 2 , comprising:

[0046] A sampling pipeline 10 is provided with a suction nozzle 101 at one end. The sampling pipeline 10 comprises a first sleeve and a second sleeve. The first sleeve is sleeved in the second sleeve. The end of the first sleeve is a first air inlet hole 102. The end of the first sleeve and the end of the second sleeve are connected by an arc-shaped plate 103. A second air inlet hole 104 is formed in the arc-shaped plate 103. The suction nozzle 101 sucks a certain volume of scanning liquid through the first air inlet hole 102 and the second air inlet hole 104, and suspends the scanning liquid in the suction nozzle 101 to collect metal ions on the surface of the silicon wafer to be tested;

[0047] A contact angle tester 20 is arranged on the sampling pipeline 10, and the signal monitoring area of the contact angle tester 20 is arranged around the suction nozzle 101. The contact angle tester 20 is used to collect the contact angle θ between the scanning liquid and the silicon wafer to be tested;

[0048] a driving mechanism for driving the sampling pipeline 10 to move up and down according to the contact angle θ between the scanning liquid and the silicon wafer under test collected by the contact angle tester 20.

[0049] In this embodiment, the sampling pipeline 10 adopts a double-sleeve structure of a first sleeve sleeved on a second sleeve, and the end portions are connected by an arc-shaped plate 103. The first air suction hole 102 at the end portion of the first sleeve and the second air suction hole 104 on the arc-shaped plate 103 work together to enable the suction nozzle 101 to form double negative pressure adsorption of the scanning liquid, thereby improving the adsorption force of the suction nozzle 101 on the scanning liquid. When the scanning liquid is suspended on the suction nozzle 101 for collecting metal ions on the surface of the silicon wafer under test, the situation that the scanning liquid falls due to gravity, uneven surface tension or contact pressure change is effectively reduced.

[0050] Moreover, the sampling pipeline 10 is provided with a contact angle tester 20, which collects the contact angle θ between the scanning liquid and the silicon wafer under test, as shown in Figure 3 The spreading state of the scanning liquid on different silicon wafer surfaces or different settings on the same silicon wafer surface can be determined by the contact angle θ. The driving mechanism dynamically adjusts the position of the sampling pipeline 10 according to the contact angle θ, so that the scanning liquid maintains a droplet shape that sufficiently contacts the surface of the silicon wafer under test. In this way, the real-time feedback of the contact angle θ and the dynamic adjustment of the position of the sampling pipeline 10 by the driving mechanism enable the silicon wafer surface metal collection device provided by the present application to adapt to silicon wafers with different characteristics and the surface morphology of different positions on the same silicon wafer, effectively reducing the loss of scanning liquid and increasing the contact area between the scanning liquid and the surface of the silicon wafer under test, thereby improving the recovery rate of the metal on the surface of the silicon wafer and improving the detection accuracy.

[0051] Specifically, when the contact angle θ between the scanning liquid and the silicon wafer under test collected by the contact angle tester 20 is less than a preset range, it can be considered that the scanning liquid does not completely contact the silicon wafer under test. The driving mechanism controls the sampling pipeline 10 to move towards the silicon wafer under test (i.e. to descend), so that the contact angle between the scanning liquid and the silicon wafer under test increases, thereby increasing the contact area between the scanning liquid and the surface of the silicon wafer under test, so that the scanning liquid completely contacts the silicon wafer under test, thereby improving the recovery rate of the metal on the surface of the silicon wafer.

[0052] When the silicon wafer under test is rotated and the sampling pipeline 10 is controlled to move along the radius of the silicon wafer under test to collect other metal ions on the surface of the silicon wafer under test, the contact angle θ between the scanning liquid and the silicon wafer under test collected by the contact angle tester 20 may be greater than the preset range. At this time, it can be considered that the scanning liquid excessively contacts the silicon wafer under test. The driving mechanism controls the sampling pipeline 10 to move away from the silicon wafer under test (i.e. to ascend), so that the contact angle between the scanning liquid and the silicon wafer under test decreases, thereby reducing the situation that the scanning liquid is excessively spread and spills, thereby improving the recovery rate of the metal on the surface of the silicon wafer.

[0053] In some embodiments, as shown in Figure 4 The plurality of sampling pipes 10 are arranged side by side along the radius of the silicon wafer to be tested.

[0054] In this embodiment, the plurality of sampling pipes 10 are arranged side by side along the radius of the silicon wafer to be tested, and the spacing between the plurality of sampling pipes 10 and the width of each suction nozzle 101 are adjusted to adapt to the radius of the silicon wafer to be tested. One contact angle tester 20 is arranged on each sampling pipe 10 to monitor the surface state of the silicon wafer to be tested in real time according to the radius direction. The up and down movement heights of each sampling pipe 10 can be different, and the same target contact angle can be set. When the contact angle of each sampling pipe 10 at the corresponding position reaches the target contact angle, the respective scanning liquid also makes contact. After the silicon wafer rotates one circle, the whole scanning of the silicon wafer surface is completed, and the testing efficiency and uniformity are improved.

[0055] Compared with the mode of sequentially scanning from the center to the edge by a single sampling pipe 10, the plurality of sampling pipes 10 arranged side by side can simultaneously perform the adsorption of scanning liquid and the collection of metal on different radius regions of the silicon wafer, and the collection time is greatly shortened through parallel operation. At the same time, since the contact angle detection and sampling parameters of each pipe can be independently controlled, the hydrophilic and hydrophobic properties and the flatness difference of different positions on the silicon wafer surface can be better adapted, and problems such as uneven distribution of scanning liquid and fluctuation of metal recovery rate caused by changes in the surface characteristics of the silicon wafer can be avoided, so that the metal contaminants on the whole silicon wafer can be efficiently and uniformly collected, thereby improving the accuracy and consistency of the ICP-MS detection results.

[0056] In some embodiments, the method further comprises:

[0057] A first pressure regulator is arranged in the first sleeve to adjust the adsorption force of the first air suction hole 102.

[0058] A second pressure regulator is arranged in the second sleeve to adjust the adsorption force of the second air suction hole 104.

[0059] In this embodiment, the first pressure regulator and the second pressure regulator are arranged in the first sleeve and the second sleeve of the sampling pipe 10, respectively, to independently adjust the adsorption forces of the first air suction hole 102 and the second air suction hole 104. In this way, the size of the double negative pressure can be flexibly adjusted according to different characteristics of the silicon wafer and the surface morphology of different positions on the same silicon wafer. For example, when facing a silicon wafer with strong hydrophobicity, the adsorption forces of the two air suction holes are increased to stabilize the liquid droplets; when processing a hydrophilic silicon wafer, the adsorption forces are appropriately reduced to avoid excessive spreading of the scanning liquid, so as to accurately control the morphology and contact area of the scanning liquid on the silicon wafer surface, reduce the loss of scanning liquid, and improve the metal collection efficiency and detection accuracy.

[0060] The first suction hole 102 forms a basic liquid drop shape by adsorbing the scanning liquid through negative pressure, and adjusts the adsorption force according to the volume and type of the scanning liquid, and controls the contact area of the scanning liquid and the silicon wafer; the second suction hole 104 further adjusts the adsorption force to finely control the liquid drop spreading state according to the local roughness and hydrophilic-hydrophobic mutation area of the surface of the silicon wafer to be measured, reduces the loss and splashing of the scanning liquid, and forms a main and auxiliary control mechanism to realize the overall dynamic management of the scanning liquid shape and ensure the stable and efficient collection of the scanning liquid.

[0061] The embodiment of the present application also provides a silicon wafer surface metal collection method, as shown in the figure, applied to the silicon wafer surface metal collection device, the method comprises: Figure 5

[0062] Step 501, the adsorption force of the suction nozzle is adjusted to adsorb the scanning liquid to the suction nozzle, and the scanning liquid is suspended on the surface of the silicon wafer to be measured by driving the sampling pipeline through the driving mechanism;

[0063] In the embodiment, the suction nozzle is located at the end of the sampling pipeline, the sampling pipeline adopts a double-sleeve structure of a first sleeve sleeved on a second sleeve, the end is connected through an arc plate, and the first suction hole at the end of the first sleeve and the second suction hole on the arc plate cooperate to form double negative pressure adsorption of the scanning liquid by the suction nozzle, thereby improving the adsorption force of the suction nozzle to the scanning liquid. When the scanning liquid is suspended on the suction nozzle to collect metal ions on the surface of the silicon wafer to be measured, the situation that the scanning liquid falls due to gravity, uneven surface tension or contact pressure change is effectively reduced.

[0064] In some embodiments, the method for adjusting the adsorption force of the suction nozzle to adsorb the scanning liquid to the suction nozzle comprises:

[0065] The second parameter information of the scanning liquid is obtained, and the second parameter information includes the volume of the scanning liquid and the type of the scanning liquid;

[0066] The first adsorption force of the first suction hole and the second adsorption force of the second suction hole are determined according to the second parameter information, and the adsorption force of the suction nozzle includes the first adsorption force and the second adsorption force;

[0067] The adsorption force of the first suction hole is adjusted to the first adsorption force, and the adsorption force of the second suction hole is adjusted to the second adsorption force, so that the scanning liquid is adsorbed to the suction nozzle, and the scanning liquid is attached to the arc plate.

[0068] ​In this embodiment, the second parameter information of the scanning liquid, such as the volume and type of the scanning liquid, directly affects the surface tension and fluidity of the scanning liquid (for example, a larger volume of scanning liquid requires greater adsorption force to maintain the shape); then, the basic adsorption force of the first suction hole is determined based on the second parameter information of the scanning liquid, and the auxiliary adsorption force of the second suction hole is adjusted according to the type of the scanning liquid (such as hydrophilic or hydrophobic solution), and the liquid drop spreading state is optimized in advance for the possible mutation area on the surface of the silicon wafer; finally, by independently regulating the adsorption forces of the two suction holes, the scanning liquid is stably adsorbed to the suction nozzle while being closely attached to the arc-shaped plate. In this way, under different scanning liquid characteristics and different surface conditions of the silicon wafer to be tested, the liquid drop shape can be dynamically managed in all directions, and the stability and efficiency of metal collection are improved.

[0069] In step 502, during the process of collecting metal ions on the surface of the silicon wafer to be tested by the scanning liquid, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested, and obtains a first contact angle corresponding to a first contact position on the silicon wafer to be tested, the first contact position being any position on the surface of the silicon wafer to be tested;

[0070] In this embodiment, a contact angle tester is arranged on the sampling pipeline. The contact angle tester collects the contact angle θ between the scanning liquid and any position on the silicon wafer to be tested. The spreading state of the scanning liquid on different silicon wafer surfaces or different settings on the same silicon wafer surface can be determined by the contact angle θ. The spreading state of the scanning liquid on different positions of the silicon wafer is dynamically monitored, which provides data support for subsequent feedback control of the sampling pipeline position and adsorption force based on the contact angle, ensures sufficient contact between the scanning liquid and the silicon wafer surface, and improves the metal ion collection efficiency and detection accuracy.

[0071] In step 503, when the first contact angle is less than the second contact angle, the sampling pipeline carrying the scanning liquid is driven to move towards the silicon wafer to be tested until the first contact angle reaches the second contact angle, and the second contact angle is a preset contact angle determined according to the silicon wafer to be tested.

[0072] In this embodiment, when the first contact angle between the scanning liquid and the silicon wafer to be tested collected by the contact angle tester is less than the second contact angle (i.e. the preset contact angle determined according to the surface state of the silicon wafer to be tested), it can be considered that the scanning liquid and the silicon wafer to be tested are not in complete contact. The sampling pipeline carrying the scanning liquid is controlled by the driving mechanism to move (i.e. descend) towards the silicon wafer to be tested, so that the contact angle between the scanning liquid and the silicon wafer to be tested increases until the first contact angle reaches the second contact angle, thereby increasing the contact area between the scanning liquid and the silicon wafer to be tested, so that the scanning liquid and the silicon wafer to be tested are in complete contact, thereby improving the recovery rate of the silicon wafer surface metal.

[0073] When the rotation of the to-be-tested silicon wafer and the control of the sampling pipeline moving along the radius of the to-be-tested silicon wafer are performed to collect other metal ions on the surface of the to-be-tested silicon wafer by scanning liquid, the contact angle between the scanning liquid and the to-be-tested silicon wafer collected by the contact angle tester can be greater than a preset range, at this time, it can be considered that the scanning liquid excessively contacts the to-be-tested silicon wafer, and the driving mechanism is controlled to move the sampling pipeline away from the to-be-tested silicon wafer (that is, upward), so that the contact angle between the scanning liquid and the to-be-tested silicon wafer is reduced, thereby reducing the situation that the scanning liquid is prone to excessive spreading and overflow, and the metal recovery rate on the surface of the silicon wafer is improved.

[0074] In the embodiment of the present application, the suction nozzle can form double negative pressure adsorption of the scanning liquid, and when the scanning liquid is suspended in the suction nozzle to collect metal ions on the surface of the to-be-tested silicon wafer by adjusting the adsorption force of the suction nozzle, the situation that the scanning liquid falls due to gravity, uneven surface tension or contact pressure change is effectively reduced; and the contact angle between the scanning liquid and the to-be-tested silicon wafer collected by the contact angle tester can determine the spreading state of the scanning liquid on different silicon wafer surfaces or different settings on the same silicon wafer surface, and the position of the sampling pipeline is dynamically adjusted according to the contact angle, so that the scanning liquid maintains the droplet shape of sufficient contact with the surface of the to-be-tested silicon wafer, which can adapt to silicon wafers with different characteristics and the surface morphology of different positions of the same silicon wafer. The loss of the scanning liquid is effectively reduced, the contact area between the scanning liquid and the surface of the to-be-tested silicon wafer is increased, and thus the metal recovery rate on the surface of the silicon wafer is improved, and the detection accuracy is improved.

[0075] In some embodiments, the second contact angle is greater than or equal to 90 degrees.

[0076] In the embodiment, when the first contact angle between the scanning liquid and the to-be-tested silicon wafer collected by the contact angle tester is less than 90 degrees, it can be considered that the scanning liquid does not completely contact the to-be-tested silicon wafer at this time, the driving mechanism is controlled to move the sampling pipeline carrying the scanning liquid towards the to-be-tested silicon wafer (that is, downward), so that the contact angle between the scanning liquid and the to-be-tested silicon wafer is increased, until the first contact angle reaches 90 degrees, thereby increasing the contact area between the scanning liquid and the surface of the to-be-tested silicon wafer, so that the scanning liquid completely contacts the to-be-tested silicon wafer, and thus the metal recovery rate on the surface of the silicon wafer is improved. The contact angle greater than or equal to 90 degrees increases the contact area between the scanning liquid and the surface of the to-be-tested silicon wafer, so that the scanning liquid completely contacts the to-be-tested silicon wafer, and the dissolution efficiency of metal ions is improved, thereby ensuring sufficient dissolution and efficient recovery of metal ions under complex surface conditions.

[0077] In some embodiments, before driving the sampling pipeline to move the scanning liquid towards the to-be-tested silicon wafer until the first contact angle reaches the second contact angle, the method further comprises:

[0078] obtaining first parameter information of the silicon wafer, the first parameter information including silicon wafer thickness and silicon wafer surface state information, the silicon wafer surface state information including hydrophilicity, hydrophobicity and roughness;

[0079] determining the second contact angle according to the first parameter information and prior data, the prior data including parameter information of a sample wafer and a preset contact angle corresponding to the sample wafer respectively.

[0080] In this embodiment, before driving the sampling pipeline to contact the scanning liquid with the wafer to be tested, the first parameter information of the wafer to be tested, such as the thickness and surface state (hydrophilicity, hydrophobicity, roughness), is obtained, and then the second contact angle suitable for the wafer to be tested is determined by combining the parameter of the sample wafer with the prior data of the corresponding preset contact angle, so as to provide accurate basis for the subsequent operation of moving the sampling pipeline to the first contact angle to reach the second contact angle, and ensure that the scanning liquid forms the best contact state on the surface of the wafer to be tested, thereby laying a foundation for efficient collection of metal ions.

[0081] The prior data is based on the test results of historical samples, and provides matched preset contact angles for sample wafers with different parameter information. When the first parameter information of the wafer to be tested matches the parameter information of the wafer, the prior data can be directly used as a basis for regulating the adsorption force and the contact angle. In this embodiment, the data-driven mode rather than the experience-based judgment mode can adapt to wafers with different characteristics, increase the contact area of the scanning liquid and the surface of the wafer to be tested, and thus improve the metal recovery rate on the surface of the wafer and the detection accuracy.

[0082] In some embodiments, during the process of collecting metal ions on the surface of the wafer to be tested by the scanning liquid, the contact angle tester collects the contact angle between the scanning liquid and the wafer to be tested, and obtains a first contact angle corresponding to a first contact position of the wafer to be tested, including:

[0083] The contact angle tester collects the contact angle between the scanning liquid and the wafer to be tested, and obtains a first contact angle corresponding to a first contact position of the wafer to be tested, with the scanning of the scanning liquid on the surface of the wafer to be tested as a period.

[0084] In this embodiment, during the process of collecting metal ions on the surface of the wafer to be tested by the scanning liquid, the contact angle tester collects the contact angle between the scanning liquid and the wafer to be tested at a first contact position (i.e. the current position) at a preset distance (such as every 1 mm) of the movement of the scanning liquid on the surface of the wafer to be tested, so as to dynamically track the spreading state of the scanning liquid at different positions. This periodic collection mode can ensure the continuity and full coverage of the contact angle data when scanning the whole area of the wafer to be tested, provide high-frequency feedback data for the real-time adjustment of the sampling pipeline position and the adsorption force by the driving mechanism, and ensure the stability of the whole collection process.

[0085] In some embodiments, during the process of collecting metal ions on the surface of the silicon wafer by the scanning liquid, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to obtain a first contact angle corresponding to a first contact position on the surface of the silicon wafer, including:

[0086] performing flatness detection on the surface of the silicon wafer to obtain a detection result;

[0087] In the case where the detection result indicates that the difference between the first surface flatness and the second surface flatness exceeds a preset threshold, when the scanning liquid scans to the first contact position on the surface of the silicon wafer, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to obtain a first contact angle corresponding to the first contact position on the surface of the silicon wafer.

[0088] wherein the first surface flatness is the surface flatness at the first contact position on the silicon wafer, and the second surface flatness is the surface flatness at a second contact position adjacent to the first contact position.

[0089] In this embodiment, the surface flatness of the silicon wafer is detected first, and when it is found that the difference between the surface flatness of the first contact position and the surface flatness of the adjacent last position (second contact position) exceeds a preset threshold (such as roughness change > 0.5 nm), the contact angle tester triggers the collection of the contact angle when the scanning liquid reaches the first contact position. In this way, the area where the surface flatness of the silicon wafer changes is focused on, and redundant collection in the flat area is avoided, which reduces the amount of data and improves the detection efficiency.

[0090] For example, at the position where the surface flatness differs, the spreading state of the scanning liquid is easily affected, and at this time the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to obtain a first contact angle corresponding to the first contact position on the silicon wafer, so as to accurately guide the driving mechanism to adjust the height of the sampling pipe or the adsorption force, and ensure that the scanning liquid can fully contact the silicon wafer in the complex topography area, thereby improving the metal ion recovery rate.

[0091] In some embodiments, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to obtain a first contact angle corresponding to a first contact position on the silicon wafer, including:

[0092] The contact angle tester collects a plurality of contact angles between the scanning liquid and the silicon wafer, and the plurality of contact angles are contact angles collected around the first contact position;

[0093] The smallest contact angle in the plurality of contact angles is determined as the first contact angle.

[0094] In the embodiment, during the contact angle acquisition process, the contact angle tester collects multiple contact angles around the first contact position of the silicon wafer to be measured. By obtaining the contact angle data at different angles around the position, the smallest contact angle is then determined as the first contact angle corresponding to the first contact position. In this way, the measurement deviation of the contact angle caused by local micro-defects (such as protrusions and pits) on the surface of the silicon wafer to be measured or uneven distribution of the scanning liquid can be effectively avoided. The smallest contact angle is used as a reference value for characterizing the actual spreading state of the scanning liquid at the position, which can reflect the morphology of the scanning liquid at the limited spreading position, provide a more reliable basis for subsequent adjustment of the sampling pipe position by the driving mechanism, and ensure accurate evaluation of the contact state between the scanning liquid and the silicon wafer under complex surface conditions, thereby improving the accuracy of metal collection. The smallest contact angle in the multiple contact angles is used as the reference value for subsequent adjustment, so that silicon wafers with different surface states (hydrophilic or hydrophobic) and different thicknesses (silicon wafers with EPI layer, polysilicon layer, SiO2 layer, or different thicknesses of the silicon wafer itself) can be dynamically adjusted, so that the scanning liquid maintains a droplet shape that fully contacts the surface of the silicon wafer to be measured, thereby expanding the application range.

[0095] It should be noted that in this document, the terms "comprising", "including", or any other variant thereof are intended to cover non-exclusive inclusions, so that a process, method, article or device that includes a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such a process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or device that includes the element.

[0096] From the above description of the embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be realized by software and a necessary general hardware platform, of course, they can also be realized by hardware, but in many cases the former is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes a plurality of instructions for causing a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in various embodiments of the present application.

[0097] In the method embodiments of the present disclosure, the serial numbers of the steps cannot be used to limit the sequence of the steps, and for those skilled in the art, the changes in the sequence of the steps without creative labor are also within the protection scope of the present disclosure.

[0098] It should be noted that each of the embodiments in the present specification is described in a progressive manner, and the same or similar parts between the embodiments can be mutually referred to, and each of the embodiments focuses on the differences from other embodiments. In particular, for the embodiments, since they are basically similar to the product embodiments, they are described more simply, and the related parts can be referred to the part of the description of the product embodiments.

[0099] The above is the preferred embodiment of the present disclosure, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the present disclosure, a number of improvements and refinements can be made, which should also be considered as the protection scope of the present disclosure.

Claims

1. A silicon wafer surface metal collection device, characterized in that: include: A sampling pipe, one end of which is provided with a suction nozzle, the sampling pipe comprising a first sleeve and a second sleeve, the first sleeve being sleeved in the second sleeve, the end of the first sleeve being a first suction hole, and the end of the first sleeve being connected to the end of the second sleeve via an arc-shaped plate, the arc-shaped plate being provided with a second suction hole, the suction nozzle sucking a set volume of scanning liquid through the first suction hole and the second suction hole, and suspending the scanning liquid in the suction nozzle to collect metal ions on the surface of the silicon wafer to be tested; A contact angle tester is provided on the sampling pipe, and a signal monitoring area of ​​the contact angle tester is arranged around the suction nozzle, and the contact angle tester is used to collect the contact angle between the scanning liquid and the silicon wafer to be tested; A driving mechanism is used to drive the sampling pipe to rise and fall according to the contact angle between the scanning liquid and the silicon wafer to be tested collected by the contact angle tester.

2. The device according to claim 1, characterized in that The plurality of sampling pipes are arranged side by side along the radius of the silicon wafer to be tested.

3. The device according to claim 1, characterized in that Also includes: a first pressure regulator, the first pressure regulator being provided on the first sleeve to adjust the adsorption force of the first suction hole; The second pressure regulator is provided on the second sleeve to adjust the adsorption force of the second suction hole.

4. A method for collecting metal from the surface of a silicon wafer, characterized in that: The method applied to the silicon wafer surface metal collection device according to any one of claims 1 to 3 comprises: regulating the adsorption force of the suction nozzle to adsorb the scanning liquid onto the suction nozzle, and driving the sampling pipe through the driving mechanism to suspend the scanning liquid on the surface of the silicon wafer to be tested; During the process of collecting the metal ions on the surface of the silicon wafer to be tested by the scanning liquid, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested to obtain a first contact angle corresponding to a first contact position on the silicon wafer to be tested, where the first contact position is any position on the surface of the silicon wafer to be tested; When the first contact angle is smaller than the second contact angle, the sampling pipe is driven to carry the scanning liquid toward the silicon wafer to be tested until the first contact angle reaches the second contact angle, which is a preset contact angle determined according to the silicon wafer to be tested.

5. The method according to claim 4, characterized in that Before driving the sampling pipe to carry the scanning liquid toward the silicon wafer to be tested until the first contact angle reaches the second contact angle, the method further includes: Acquiring first parameter information of the silicon wafer, the first parameter information including silicon wafer thickness and silicon wafer surface state information, the silicon wafer surface state information including hydrophilicity, hydrophobicity and roughness; The second contact angle is determined according to the first parameter information and priori data, where the priori data includes parameter information of sample silicon wafers and preset contact angles corresponding to the sample silicon wafers.

6. The method according to claim 4, characterized in that In the process of collecting metal ions on the surface of the silicon wafer to be tested by the scanning liquid, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested to obtain a first contact angle corresponding to a first contact position on the silicon wafer to be tested, including: The contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested with the scanning liquid scanning a preset distance on the surface of the silicon wafer to be tested as a period, and obtains a first contact angle corresponding to a first contact position on the silicon wafer to be tested.

7. The method according to claim 4, characterized in that In the process of collecting metal ions on the surface of the silicon wafer to be tested by the scanning liquid, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested to obtain a first contact angle corresponding to a first contact position on the silicon wafer to be tested, including: Performing a flatness test on the surface of the silicon wafer to be tested to obtain a test result; When the detection result indicates that the difference between the flatness of the first surface and the flatness of the second surface exceeds a preset threshold, when the scanning liquid scans to the first contact position on the surface of the silicon wafer to be tested, the contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested to obtain a first contact angle corresponding to the first contact position on the silicon wafer to be tested; The first surface flatness is the surface flatness at the first contact position of the silicon wafer to be tested, and the second surface flatness is the surface flatness at the second contact position of the silicon wafer to be tested, where the second contact position is the upper position adjacent to the first contact position.

8. The method according to any one of claims 6 and 7, characterized in that The contact angle tester collects the contact angle between the scanning liquid and the silicon wafer to be tested, and obtains a first contact angle corresponding to a first contact position of the silicon wafer to be tested, comprising: The contact angle tester collects a plurality of contact angles between the scanning liquid and the silicon wafer to be tested, wherein the plurality of contact angles are contact angles collected around the first contact position; The smallest contact angle among the plurality of contact angles is determined as the first contact angle.

9. The method according to claim 4, characterized in that The adjusting the adsorption force of the nozzle to adsorb the scanning liquid to the nozzle includes: Acquiring second parameter information of the scanning liquid, where the second parameter information includes a volume of the scanning liquid and a type of the scanning liquid; determining a first adsorption force of the first suction hole and a second adsorption force of the second suction hole according to the second parameter information, wherein the adsorption force of the suction nozzle includes the first adsorption force and the second adsorption force; The adsorption force of the first suction hole is adjusted to the first adsorption force and the adsorption force of the second suction hole is adjusted to the second adsorption force, so that the scanning liquid is adsorbed on the suction nozzle and the scanning liquid is adhered to the curved plate.

10. The method according to claim 4, characterized in that The second contact angle is greater than or equal to 90 degrees.

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