Testing machine and wafer testing method

Abstract

The invention provides a testing machine and a wafer testing method. The testing machine comprises a base, a testing mechanism and a first detection element. The testing mechanism comprises a bearing part, a force transmission part and a force application part; the bearing piece is arranged on the base; the force transmission piece is located on the side, away from the base, of the bearing piece. First teeth are arranged on the surface, facing the bearing piece, of the force transmission piece. The force application piece is connected with the force transmission piece, drives the force transmission piece to be close to or away from the bearing piece and enables the force transmission piece to apply pressure to the bearing piece; the first detection element is arranged on the base and / or the bearing part and used for detecting the pressure borne by the wafer on the bearing part. When the wafer is tested by using the testing machine, the wafer is firstly placed between the bearing part and the force transmission part, then the force transmission part is controlled by the force application part to apply pressure to the wafer until the wafer is broken, the pressure borne by the wafer when the wafer is broken is obtained based on the detection value of the first detection element, and the withstand voltage value of the wafer is obtained. The method is easy and convenient to operate and high in feasibility.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductors, and in particular relates to a testing machine and a wafer testing method. Background Art

[0002] In the semiconductor manufacturing process, the withstand voltage value of the wafer represents the strength of the wafer itself and is an extremely important parameter. Obtaining the withstand voltage value of the wafer can, on the one hand, control the various energy ranges applied to the wafer in subsequent processing to reduce the occurrence of wafer breakage, and on the other hand, perform defect analysis on the wafer to adjust the wafer growth process to improve the strength of the wafer.

[0003] However, there is no method in the prior art that can intuitively and quickly obtain the withstand voltage value of a wafer. Summary of the invention

[0004] The object of the present invention is to provide a testing machine and a wafer testing method, which is intended to test the wafer to obtain the withstand voltage value of the wafer.

[0005] To achieve the above object, the present invention provides a testing machine for testing the withstand voltage value of a wafer; the testing machine comprises:

[0006] Base;

[0007] A testing mechanism, comprising a bearing member, a force transmitting member and a force applying member; the bearing member is arranged on the base and used to bear the wafer; the force transmitting member is located on a side of the bearing member away from the base, and a first tooth is arranged on a surface of the force transmitting member facing the bearing member; the force applying member is connected to the force transmitting member and is configured to drive the force transmitting member to move in a direction approaching or away from the bearing member, and to enable the force transmitting member to apply pressure to the wafer carried by the bearing member; and,

[0008] The first detection element is disposed on the base and / or the carrier and is configured to detect the pressure exerted on the wafer.

[0009] Optionally, the end surface of the first tooth close to the end of the bearing member is at least partially located on a first circle; a second tooth is provided on the surface of the bearing member facing the force transmission member, and the end surface of the second tooth away from the base is at least partially located on a second circle, and the second circle is of equal diameter and coaxial with the first circle; the second tooth is staggered with the first tooth in the circumferential direction of the first circle;

[0010] The first detection element is arranged between the base and the supporting member.

[0011] Optionally, the number of the first teeth is at least one, and the number of the second teeth is at least three.

[0012] Optionally, the testing mechanism also includes a limit member, which is disposed on the base and / or the supporting member; the limit member is arranged around the axis of the first circle, and the limit member has a preset position on the surface of the side facing the axis of the first circle, and the preset position is located on a third circle; the third circle is coaxial with the first circle, the diameter of the third circle is larger than the diameter of the first circle, and the third circle is coplanar with the end face of the second tooth away from the base.

[0013] Optionally, the test machine further comprises a frame, which is arranged on the base and at least partially located on a side of the force transmission member away from the bearing member;

[0014] The force-applying member includes a force-generating part, a telescopic shaft, a first connecting member and a second connecting member; the force-generating part is connected to the frame and is located on the side of the force-transmitting member away from the bearing member; the telescopic shaft is connected to the force-generating part and is coaxially arranged with the first circle; the first connecting member is perpendicular to the telescopic shaft, and the first connecting member is connected to the side of the telescopic shaft away from the force-generating part; a plurality of the second connecting members all extend along the axial direction of the telescopic shaft, and a plurality of the second connecting members are spaced apart around the axis of the telescopic shaft; one end of the second connecting member is connected to the first connecting member, and the other end is connected to the force-transmitting member.

[0015] Optionally, the testing machine further includes an image capturing element, wherein the image capturing element is disposed on a side of the force transmitting member facing away from the supporting member, and a field of view of the image capturing element covers an area defined by a third circle, wherein the third circle is coaxial with the first circle, a diameter of the third circle is greater than a diameter of the first circle, and the third circle is coplanar with an end portion of the second tooth away from the base.

[0016] Optionally, the force transmission member is a circular ring structure coaxial with the first circle; and the lens of the image acquisition element is coaxially arranged with the force transmission member.

[0017] Optionally, the force transmission member is a transparent structural member.

[0018] Optionally, the testing machine further includes a second detection element, and the second detection element is configured to detect whether the distance between the force transmission member and the support member is less than or equal to a preset distance.

[0019] To achieve the above object, the present invention further provides a wafer testing method, which is performed based on the testing machine as described in any of the preceding items, and the testing method comprises:

[0020] placing a wafer on the carrier and making the target area of ​​the wafer correspond to the first tooth;

[0021] Controlling the force applying member to operate and driving the force transmitting member to move in a direction close to the supporting member, so that the first tooth contacts the target area of ​​the wafer, and then the force transmitting member applies pressure to the target area of ​​the wafer until the wafer breaks;

[0022] The pressure applied by the force transmission member to the wafer when the wafer is broken is obtained through the first detection element as the withstand pressure value of the wafer at the target area.

[0023] Optionally, the pressure applied by the force transmission member to the wafer changes in a step-like manner;

[0024] The process of the force transmission member applying pressure to the wafer includes a plurality of sub-processes; in any of the sub-processes, the pressure applied by the force transmission member to the wafer first increases uniformly from zero to a preset pressure of the corresponding sub-process, then maintains the pressure for a preset time, and finally the force transmission member instantly releases the pressure applied to the wafer;

[0025] In two adjacent sub-processes, the preset pressure corresponding to the latter sub-process is greater than the preset pressure corresponding to the former sub-process.

[0026] Optionally, the force transmission member and the bearing member are arranged in a vertical direction, and the bearing member is below the force transmission member; and the first detection element is arranged between the base and the bearing member;

[0027] The wafer testing method further includes:

[0028] When the pressure detected by the first detection element decreases instantaneously and then increases again, and the minimum pressure after the decrease is greater than the sum of the gravity of the carrier and the gravity of the wafer, the force applying member is controlled to stop running.

[0029] Optionally, the test machine further includes a second detection element;

[0030] The wafer testing method further includes:

[0031] The second detection element is used to detect whether the distance between the force transmission member and the support member is less than or equal to a preset distance. If so, the force application member is controlled to stop running; the preset distance is less than the thickness of the wafer.

[0032] Optionally, the test machine further includes an image acquisition element;

[0033] The test method also includes:

[0034] The image acquisition element is used to acquire a video of crack growth on the wafer.

[0035] Optionally, the distance from any point on the target area to the edge of the wafer is no more than 20 mm.

[0036] Compared with the prior art, the testing machine and wafer testing method of the present invention have the following advantages:

[0037] The aforementioned test machine includes a base, a test mechanism, and a first detection element; the test mechanism includes a carrier, a force transmission member, and a force applying member; the carrier is arranged on the base and is used to carry a wafer; the force transmission member is located on the side of the carrier away from the base, and the force transmission member is provided with a first tooth on the surface of the carrier facing the carrier; the force applying member is connected to the force transmission member, and is configured to drive the force transmission member to move in a direction approaching or away from the carrier, and to make the force transmission member apply pressure to the wafer carried by the carrier; the first detection element is arranged on the base and / or the carrier, and is configured to detect the pressure exerted on the wafer. When the wafer is tested using the test machine, the wafer is first placed on the carrier, and then the force-applying member is controlled to operate so that the first tooth of the force-transmitting member contacts the target area of ​​the wafer, and then pressure is applied to the target area of ​​the wafer until the wafer breaks. The pressure applied by the force-transmitting member to the wafer when the wafer breaks can be obtained through the detection value of the first detection element, and this is used as the withstand voltage value of the wafer at the target area. This test method has the advantages of simple and convenient operation, strong feasibility, and the ability to quickly obtain the withstand voltage value of the target area of ​​the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings are used to better understand the present invention and do not constitute an improper limitation of the present invention.

[0039] Figure 1 is a schematic structural diagram of a test machine provided according to an embodiment of the present invention;

[0040] Figure 2 is a schematic diagram of the wafer;

[0041] Figure 3 is a schematic structural diagram of a force transmission member of a test machine provided according to an embodiment of the present invention;

[0042] Figure 4 yes Figure 3 AA cross-sectional view of the force transmission member of the test machine shown;

[0043] Figure 5 It is a schematic diagram of the change in pressure applied by the force transmission member to the wafer when the wafer is subjected to strength testing using the test machine provided by the embodiment of the present invention.

[0044] [Description of reference numerals is as follows]:

[0045] 100-base, 200-test mechanism, 210-carrying member, 211-second tooth, 220-force transmission member, 221-first tooth, 230-force application member, 231-force generating part, 232-telescopic shaft, 233-first connecting member, 234-second connecting member, 240-limiting member, 241-preset position, 201-first circle, 300-first detection element, 400-second detection element, 410-light emitting module, 420-light receiving module, 500-frame, 600-image acquisition element, 10-wafer, 11-target area, DETAILED DESCRIPTION

[0046] The following is an explanation of the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the present embodiment only illustrate the basic concept of the present invention in a schematic manner, and only the components related to the present invention are shown in the figure instead of being drawn according to the number, shape and size of the components in the actual implementation. The type, quantity and proportion of each component in the actual implementation can be a random change, and the component layout type may also be more complicated.

[0047] In addition, each embodiment of the following description has one or more technical features, but this does not mean that the user of the present invention must implement all the technical features in any embodiment at the same time, or can only implement part or all of the technical features in different embodiments separately. In other words, under the premise that implementation is possible, those skilled in the art can selectively implement part or all of the technical features in any embodiment according to the disclosure of the present invention and according to the design specifications or implementation requirements, or selectively implement a combination of part or all of the technical features in multiple embodiments, thereby increasing the flexibility of the implementation of the present invention.

[0048] As used in this specification, the singular forms "one", "an", and "the" include plural objects, and the plural form "a plurality" includes more than two objects, unless the content clearly indicates otherwise. As used in this specification, the term "or" is generally used in a sense that includes "and / or", unless the content clearly indicates otherwise, and the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be directly connected or indirectly connected through an intermediate medium, and it can be a connection between two elements or an interactive relationship between two elements. Relational terms such as the terms "first", "second", etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations, nor do they indicate or imply relative importance or implicitly indicate the number of technical features indicated. It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] The object of the present invention is to provide a testing machine, which can test the strength of a wafer to obtain the withstand voltage value of the wafer, and then quantify the strength level of the wafer, so as to facilitate quality management of the wafer in actual production.

[0050] In order to make the purpose, advantages and features of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings. It should be noted that the drawings are all in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. The same or similar reference numerals in the drawings represent the same or similar components.

[0051] Figure 1 FIG. 1 is a schematic diagram showing the structure of a test machine provided by some embodiments of the present invention. Figure 1As shown, the test machine at least includes a base 100, a test mechanism 200, and a first detection element 300. The test mechanism 200 includes a carrier 210, a force transmission member 220, and a force application member 230. The carrier 210 is arranged on the base 100 and is used to carry the wafer 10 to be tested. The force transmission member 220 is located on the side of the carrier 210 away from the base 100, and a first tooth 221 is also provided on the surface of the force transmission member 220 facing the carrier 210. The force application member 230 is connected to the force transmission member 220, and is configured to drive the force transmission member 220 to move in a direction close to or away from the carrier 210, and to make the force transmission member 220 apply pressure to the wafer 10 carried by the carrier 210. The first detection element 300 is arranged on the base 100 and / or the carrier 210, and is configured to detect the pressure on the wafer 10.

[0052] The testing machine can be used to test the strength of the wafer 10 to obtain the withstand voltage value of the wafer 10 at the target area 11. The specific testing method is as follows: First, under the premise that the distance between the carrier 210 and the force transmission member 220 is greater than the thickness of the wafer 10, the wafer 10 is placed on the carrier 210, and the target area 11 of the wafer 10 corresponds to the first tooth 221. Then, the force-applying member 230 is controlled to operate to drive the force transmission member 220 to move in a direction close to the carrier 210 until the first tooth 221 contacts the target area 11 of the wafer 10, and further the force transmission member 220 applies pressure to the target area 11 of the wafer 10 until the wafer 10 breaks. The distance between the force transmission member 220 and the carrier 210 refers to the distance from the end of the first tooth 221 close to one end of the carrier 210 to the end of the carrier 210 away from the base 100.

[0053] The first detection element 300 may be any suitable pressure detection element in the prior art, and is used to detect the pressure exerted on the wafer 10 in real time during the entire test process. Thus, the pressure exerted on the wafer 10 when the wafer 10 is broken can be obtained according to the detection value of the first detection element 300, and then the withstand voltage value of the wafer 10 at the target area 11 can be obtained. The withstand voltage value of the wafer 10 at the target area 11 is used to characterize the strength of the wafer 10 at the target area 11.

[0054] In practice, for the same batch of wafers 10, a strength test can be performed on a preset number of wafers 10 to obtain the strength distribution of the preset number of wafers 10 at the target area 11. Then, the quality management standard of the wafers 10 of this batch can be formulated according to the strength distribution of the wafers 10 at the target area 11, so that when the wafers 10 of this batch are subsequently processed, the energy applied to the wafers 10 can be controlled according to the quality management standard to reduce the breakage rate of the wafers 10. In addition, the growth process of the wafers 10 can be analyzed and regulated according to the strength distribution of the wafers 10 of this batch at the target area 11, and the strength of the subsequently grown wafers 10 can be regulated. The preset number is determined according to needs, for example, 25 wafers.

[0055] Preferably, the target area 11 is located near the edge of the wafer 10. This is because, compared with the middle area, the edge area of ​​the wafer 10 is more prone to defects, and therefore the edge area of ​​the wafer 10 is more fragile and more prone to breakage. Optionally, the distance L1 (e.g., Figure 2 The contact area between each first tooth 221 and the wafer 10 is not less than 1 mm. 2 , and no more than 4mm 2 .

[0056] The number of the first teeth 221 is at least one. Figure 2 As shown, the target area 11 is a circle concentric with the wafer 10. At this time, it is expected that the number of the first teeth 221 is as large as possible, for example, 90 or more. All the first teeth 221 are arranged along a first circle 201 (such as Figure 3 The first teeth 221 are arranged at intervals (as shown by the red dotted line in FIG. 1 ), for example, are distributed at equal intervals along the first circle 201. This is because the more the first teeth 221 there are, the easier it is for the first teeth 221 to contact the surface of the wafer 10 on the side facing the force transmission member 220 and the defects located in the target area 11, so that the wafer 10 can be broken at a smaller pressure, thereby improving the accuracy and reliability of the strength test of the wafer 10. All the first teeth 221 are arranged at intervals along a first circle 201 corresponding to the target area, which means that the end surface of the first tooth 221 close to one end of the carrier 210 is at least partially located on the first circle 201.

[0057] When the target area 11 is a circle, a circular ring line can be used to mark the target area 11 on the wafer 10, and the line width of the circular ring line is set according to the width of the target area 11 in the radial direction of the wafer 10. In this way, the first circle 201 corresponds to the target area 11, which means that the diameter of the first circle 201 is greater than or equal to the diameter of the circle where the edge of the circular ring line on the side close to the axis of the wafer 10 (that is, the inner edge of the circular ring line) is located, and is less than or equal to the diameter of the circle where the edge of the circular ring line on the side away from the axis of the wafer 10 (that is, the outer edge of the circular ring line) is located. Therefore, during the test process, as long as the first circle 201 is coaxial with the wafer 10, each of the first teeth 221 can be made to contact the target area 11. It can be understood that the distance from the inner edge of the circular ring line to the edge of the wafer 10 is not more than 20 mm, preferably not more than 10 mm.

[0058] Optionally, the testing mechanism 200 further includes a stopper 240, which is disposed on at least one of the base 100 and the carrier 210. The stopper 240 is used to constrain the position of the wafer 10 on the carrier 210 so that the wafer 10 is coaxially arranged with the first circle 201.

[0059] Specifically, the stopper 240 is arranged around the axis of the first circle 201, and the stopper 240 has a preset position 241 (( Figure 1 The preset position 241 is shown in red in the figure, and the preset position 241 is located on the third circle. In other words, the stopper 240 defines the third circle at the preset position 241. The third circle is coaxial with the first circle 201, the diameter of the third circle is greater than the diameter of the first circle 201, and the third circle is also located on the same plane as the end of the carrier 210 away from the base 100. In practice, the diameter of the third circle is equivalent to the diameter of the wafer 10, so that when the wafer 10 is placed on the carrier 210, the wafer 10 contacts the preset position 241 and is located at the third circle, so that the wafer 10 is coaxial with the first circle 201 under the constraint of the stopper 240. It should be understood that the preset position 241 includes a plurality of spaced sub-positions, and all of the plurality of sub-positions are on the third circle; or, the preset position 241 extends along the third circle.

[0060] In some examples, the position-limiting member 240 includes a plurality of position-limiting columns, the plurality of position-limiting columns are arranged at intervals around the axis of the first circle 201, for example, at equal intervals, and each of the position-limiting columns is provided with one sub-position, and the sub-positions on all the position-limiting columns together constitute the preset position 241. In other examples, the position-limiting member 240 includes a retaining wall, the retaining wall extends in the circumferential direction of the first circle 201, and preferably, the retaining wall extends at an angle greater than 180° around the axis of the first circle 201, and the preset position 241 is the same as the angle at which the retaining wall extends around the axis of the first circle 201.

[0061] Preferably, the distance from the surface of the stopper 240 on the side close to the axis of the first circle 201 to the axis of the first circle 201 gradually decreases along the direction from the force transmission member 220 to the carrier 210. Thus, when the wafer 10 is placed on the carrier 210, the surface of the stopper on the side close to the axis of the first circle 201 can guide the wafer 10.

[0062] Typically, the bearing member 210 and the force transmission member 220 are arranged in a vertical direction, and the bearing member 210 is disposed on the upper surface of the base 100 . Thus, the force transmission member 220 is located above the bearing member 210 .

[0063] Preferably, please refer back to Figure 1 , the carrier 210 is provided with second teeth 211 on the surface facing the force transmission member 220. When the carrier 210 carries the wafer 10, the wafer 10 contacts all the second teeth 211. It can be understood that the number of the second teeth 211 is at least three, and at least three second teeth 211 are arranged at intervals along a second circle (not shown in the figure), for example, arranged at equal intervals, and the second circle is equal in diameter and coaxial with the first circle 201. The second teeth 211 are also staggered with the first teeth 221 in the circumferential direction of the first circle 201. In this way, when the wafer 10 contacts all the second teeth 211, the wafer 10 can be stably carried on the carrier 210, and all the second teeth 211 are in contact with the target area 11 of the wafer 10, so that the wafer 10 is only subjected to force at the target area 11, so as to ensure that the withstand voltage value of the wafer 10 at the target area 11 is obtained through the test. In addition, the second teeth 211 can also make it easier for the wafer 10 to break when there is a defect on the surface of the wafer 10 facing the carrier 210 and located in the target area 11, so as to improve the reliability of the strength test. The contact area between the second teeth 211 and the wafer 10 is not less than 1mm 2 And no more than 4mm 2 .

[0064] The number of the second teeth 211 is as large as possible, so that the second teeth 211 can more easily contact the surface of the wafer 10 facing the force transmission member 220 and the defects located in the target area 11, so that the wafer 10 can be broken under a smaller pressure, thereby improving the accuracy and reliability of the strength test of the wafer 10. Further preferably, the second teeth 211 and the first teeth 221 are staggered on the circumference of the first circle 201, so that the test mechanism 200 can contact more defects on the wafer 10, thereby enabling the wafer 10 to be broken under a smaller pressure. The number of the second teeth 211 can be more than the number of the first teeth 221, or less than the number of the first teeth 221. Of course, the number of the second teeth 211 can also be the same as the number of the first teeth 221.

[0065] It should be noted that the rupture of the wafer 10 refers to the occurrence of cracks on the wafer 10. Specifically, for the case where the second tooth 211 is not provided on the carrier 210 and there is only one first tooth 221 on the force transmission member 220, the rupture of the wafer 10 refers to the occurrence of cracks on the portion of the wafer 10 in contact with the first tooth 221; for the case where the second tooth 211 is not provided on the carrier 210 and a plurality of first teeth 221 are provided on the force transmission member 220, the rupture of the wafer 10 refers to the occurrence of cracks on the portion of the wafer 10 in contact with any one of the first teeth 221; for the case where the second tooth 211 is provided on the carrier 210 and the first tooth 221 is provided on the force transmission member 220, the rupture of the wafer 10 refers to the occurrence of cracks on the portion of the wafer 10 in contact with any one of the first teeth 221, and / or the occurrence of cracks on the portion of the wafer 10 in contact with any one of the second teeth 211.

[0066] It should also be noted that, when the second tooth 211 exists, the end of the carrier 210 away from the base 100 refers to the end of the second tooth 211 away from the base 100 .

[0067] Optionally, in the presence of the second teeth 211, the first detection element 300 is disposed between the base 100 and the carrier 210. In this way, when the force transmission member 220 has not applied pressure to the wafer 10, the first detection element 300 detects a basic pressure due to the gravity of the carrier 210 and the wafer 10, and the basic pressure is equal to the sum of the gravity of the carrier 210 and the gravity of the wafer 10. When the force transmission member 220 applies pressure to the wafer 10, the pressure applied by the force transmission member 220 to the wafer 10 is transmitted to the carrier 210 through the wafer 10, and thus, what is detected by the first detection element 300 is the sum of the basic pressure and the pressure applied by the force transmission member 220 to the wafer 10. Therefore, the pressure applied by the force transmission member 220 to the wafer 10 is equal to the difference between the pressure detected by the first detection element 300 and the basic pressure. In other words, the withstand voltage value of the wafer 10 at the target area 11 is equal to the difference between the pressure detected by the first detection element 300 when the wafer 10 is broken and the base pressure.

[0068] It should also be noted that the first detection element 300 is in communication connection with a control unit, and the control unit receives the pressure value detected by the first detection element 300 and can directly calculate the withstand voltage value of the wafer 10. The control unit can also display the withstand voltage value of the wafer 10. The test machine can include the control unit.

[0069] It is understood that after the wafer 10 is broken, the force applying member 230 can be controlled to stop operating. In some examples, an operator manually observes whether the wafer 10 is broken, and in other examples, a monitoring element is used to monitor whether the wafer 10 is broken.

[0070] When monitoring whether the wafer 10 is broken by a monitoring element, the first detection element 300 can be used as the monitoring element. This is because, when the wafer 10 is broken, the pressure applied by the force transmission member 220 to the carrier 210 through the wafer 10 is instantly reduced to a minimum pressure. Moreover, the essence of the force transmission member 220 applying pressure to the wafer 10 is that the force transmission member 220 is subjected to a force directed from itself in the direction of the carrier 210, so that the force transmission member 220 has a tendency to move in a direction close to the carrier 210. Therefore, once the wafer 10 is broken, the force transmission member 220 can continue to move in a direction close to the carrier 210. Since the thickness of the wafer 10 is extremely small, the force transmission member 220 can contact the carrier 210 in a very short time, causing the pressure on the carrier 210 to rise rapidly. Experiments have found that the minimum pressure is greater than the base pressure. Therefore, when the pressure detected by the first detection element 300 decreases instantaneously to a minimum pressure greater than the base pressure and then increases rapidly, it can be determined that the wafer 10 is broken.

[0071] The control unit is configured to automatically determine whether the wafer 10 is broken according to the pressure value detected by the first detection element 300. Furthermore, the control unit generates and displays a prompt message after the wafer 10 is broken to prompt the operator. The control unit can display the prompt message in the form of sound prompt, flashing light, text, etc.

[0072] Alternatively, if Figure 1 As shown, the test machine may further include a second detection element 400, and monitor whether the wafer 10 is broken by the second detection element 400. The second detection element 400 may be set at any suitable position, and is configured to detect whether the distance between the force transmission member 220 and the carrier 210 is less than or equal to a preset distance. If so, it can be determined that the wafer 10 is broken, and if not, it is determined that the wafer 10 is not broken. The preset distance is less than the thickness of the wafer 10. This is because, when the wafer 10 is not broken, the distance between the force transmission member 220 and the carrier 210 is greater than or equal to the thickness of the wafer 10, and when the wafer 10 is broken, the force transmission member 220 moves in a direction close to the carrier 210, so that the distance from the force transmission member 220 to the carrier 210 is less than the thickness of the wafer 10.

[0073] The control unit is communicatively connected to the second detection unit 400 and is configured to generate and display a prompt message to prompt an operator that the wafer 10 is broken when the second detection unit 400 detects that the distance between the force transmission member 220 and the carrier 210 is less than or equal to the preset distance.

[0074] In an exemplary example, the second detection element 400 is a photoelectric sensor, and the photoelectric sensor includes a split light emitting module 410 and a light receiving module 420. The light emitting module 410 is disposed on one side of the carrier 210 in any suitable manner, and the light receiving module 420 is disposed on a side of the force applying member 230 or the force transmitting member 220 away from the axis of the first circle 201. Viewed in the circumferential direction of the first circle 201, the light receiving module 420 is aligned with the light emitting module 410, and viewed in the axial direction of the first circle 201, the propagation path of the detection light emitted by the light emitting module 410 is above the carrier 210, and when the wafer 10 is not broken and the first tooth 221 is in contact with the wafer 10, the difference between the distance L2 from the light emitting position of the light emitting module 410 to the end of the carrier 210 away from the base 0 and the distance L3 from the light receiving position of the light receiving module 420 to the end of the carrier 210 away from the base 100 is a preset value, and the preset value is greater than zero and less than the thickness of the wafer 10. Thus, when the wafer 10 is not broken, the light receiving module 420 cannot receive the detection light emitted by the light emitting module 410. When the wafer 10 is broken and the distance that the force transmitting member 220 moves in the direction close to the carrier 210 is the preset value, the light receiving position of the light receiving module 420 is directly opposite to the light emitting position of the light emitting module 410 so that the light receiving module 420 can receive the detection light emitted by the light emitting module 410. In other words, when the light receiving module 420 receives the detection light, it indicates that the wafer 10 has been broken. Of course, the positions of the light emitting module 410 and the light receiving module 420 are interchangeable.

[0075] It should be understood that the control unit can also determine whether the wafer 10 is broken based on the change in the pressure value detected by the first detection element 300 and the signal detected by the second detection element 400 at the same time.

[0076] In addition, when the wafer 10 is broken, the operator can manually control the force applying member 230 to stop running. Alternatively, the control unit is also in communication connection with the force applying member 230 so that the control unit automatically controls the force applying member 230 to stop running when the wafer 10 is broken.

[0077] Optionally, in the embodiment of the present invention, the force applying member 230 may include any suitable linear motion element, such as a combination of a motor and a lead screw nut, and the nut sleeved on the lead screw is connected to the force transmitting member (not shown in the figure).

[0078] For example, Figure 1 As shown, the force-applying member 230 includes a force-generating portion 231 and a telescopic shaft 232, wherein the telescopic shaft 232 extends along the axial direction of the first circle 201, and one axial end of the telescopic shaft 232 is connected to the force-generating portion 231, and the other axial end of the telescopic shaft 232 is connected to the force-transmitting member 220 in any appropriate manner. The force-generating portion 231 is used to generate force, and the force is transmitted to the force-transmitting member 220 through the telescopic shaft 232, so as to achieve the purpose of driving the force-transmitting member 220 to move, or causing the force-transmitting member 220 to apply pressure to the wafer 10. Specifically, when the force generating part 231 generates force and controls the telescopic shaft 232 to extend and retract in the axial direction of the testing mechanism 200, the force transmitting member 220 is driven to move in a direction approaching or away from the supporting member 210; when the first tooth 221 of the force transmitting member 220 contacts the wafer 10 and the telescopic shaft 232 has a tendency to elongate under the action of the force generated by the force generating part 231, the force transmitting member 220 applies pressure to the wafer 10.

[0079] In the embodiment of the present invention, the force-applying member 230 preferably includes the force-generating portion 231 and the telescopic shaft 232. When there are multiple first teeth 221 and the multiple first teeth 221 are arranged at intervals along the circumference of the first circle 201, the telescopic shaft 232 is preferably arranged coaxially with the first circle 201. The advantage of this is that when the force-transmitting member 220 applies pressure to the wafer 10 and the carrier 210, the force balance of the wafer 10 in the entire circumference of the target area 11 is improved.

[0080] To achieve the above-mentioned purpose, the test machine further includes a frame 500, which is arranged on the base 100 and is at least partially located on the side of the force transmission member 220 away from the support member 210. The force generating part 231 is connected to the part of the frame 500 located on the side of the force transmission member 220 away from the support member 210. At the same time, the force applying member 230 further includes a first connecting member 233 and a second connecting member 234. The force generating part 231 is connected to the frame 500 and is at least partially located on the side of the force transmission member 220 away from the support member 210, thereby making the telescopic shaft 232 coaxial with the first circle 201. The first connecting member 233 is perpendicular to the telescopic shaft 232, and the first connecting member 233 is connected to the end of the telescopic shaft 232 away from the force generating part 231. There are multiple second connecting members 234, each of which extends along the axial direction of the telescopic shaft 232 and is arranged at intervals around the axis of the telescopic shaft 232, for example, at equal intervals, and each of the second connecting members 234 is connected to the force transmission member 220. In other words, the telescopic shaft 232 is indirectly connected to the force transmission member 220 through the first connecting member 233 and the second connecting member 234. In addition, the provision of multiple second connecting members 234 can also facilitate observation of the state of the wafer 10 and cleaning of the test mechanism 200 after the wafer 10 is broken.

[0081] In an optional example, the force applying member 230 includes a hydraulic cylinder, so that the force generating part 231 is the cylinder body of the hydraulic cylinder, and the telescopic shaft 232 is the piston rod of the hydraulic cylinder. In other examples, the hydraulic cylinder can be replaced by a pneumatic cylinder or an electric telescopic rod.

[0082] In addition, the second detection element 400 may be at least partially disposed on the frame 500 , for example, one of the light emitting element 410 and the light receiving element 420 may be disposed on the frame 500 .

[0083] Furthermore, if Figure 1As shown, the test machine also includes an image acquisition element 600. The image acquisition element 600 is arranged on the side of the force transmission member 220 away from the carrier 210, and the field of view of the image acquisition element 600 covers the circular area defined by the third circle. Thus, when the wafer 10 is carried on the carrier 210, the field of view of the image acquisition element 600 covers the wafer 10. The purpose of such a setting is that the image acquisition element 600 can be used to record the growth video of the crack when the wafer 10 is broken. Therefore, those skilled in the art can know at least part of the growth path of the crack of the wafer 10 when it is broken according to the crack growth video, and then analyze the defects on the wafer 10 based on the crack growth path, which is conducive to targeted regulation of the growth process of the wafer 10.

[0084] In some examples, the force transmission member 220 is an entire transparent structure to prevent the force transmission member 220 from blocking the field of view of the image acquisition element 600 .

[0085] In other examples, such as Figure 3 and Figure 4 As shown, the force transmission member 220 is an annular structure, and the annular structure is coaxial with the first circle 201. At the same time, the lens of the image acquisition element 600 is arranged coaxially with the first circle 201. In this case, the force transmission member 220 is allowed to be made of an opaque material. At this time, the force transmission member 220 will constitute an obstruction, so that the image acquisition element 600 cannot capture the complete image of the wafer 10, but the image acquisition element 600 can still capture at least part of the growth path of the crack on the wafer 10 when it grows toward the center area of ​​the wafer 10, and capture part of the growth path of the wafer 10 when it grows toward the edge of the wafer 10.

[0086] It should be noted that when the force-applying member 230 includes the first connecting member 233 and the second connecting member 234, the image capturing element 600 can be connected to the side of the first connecting member 233 that is away from the telescopic shaft 232. In this way, the second connecting member 234 will not block the field of view of the image capturing element 600.

[0087] Furthermore, an embodiment of the present invention also provides a wafer testing method, which is performed based on the aforementioned testing machine. The testing method comprises the following steps:

[0088] Step S10 , placing the wafer 10 on the carrier 210 , and making the target area 11 of the wafer 10 correspond to the first tooth 221 .

[0089] Step S20: Control the force applying member 230 to operate, so as to drive the force transmitting member 220 to move in a direction close to the carrier 210, so that the force transmitting member 220 contacts the wafer 10, and then the force transmitting member 220 applies pressure to the wafer 10 until the wafer 10 is broken. At the same time, the first detection element 300 detects the pressure applied by the force transmitting member 220 to the wafer 10 in real time.

[0090] Step S30 , obtaining the pressure applied by the force transmission member 220 to the wafer 10 when the wafer 10 is broken according to the pressure detected by the first detection element 300 , as the withstand pressure value of the wafer 10 at the target area 11 .

[0091] It can be understood that in the step S10 , the wafer 10 is coaxial with the first circle 201 , so that in the step S20 , the first teeth 221 of the force transmission member 220 are in contact with the target area 11 of the wafer 10 .

[0092] When the carrier 210 is disposed below the force transmission member 220, and the first detection element 300 is disposed between the base 100 and the carrier 210, the first detection element 300 continuously detects pressure during the execution of step S10 and step S20. Before the force transmission member 220 applies pressure to the wafer 10, the pressure detected by the first detection element 300 is a basic pressure, which is equal to the sum of the gravity of the wafer 10 and the pressure of the carrier 10. During the process of the force transmission member 220 applying pressure to the wafer 10, the pressure detected by the first detection element 300 is equal to the sum of the basic pressure and the pressure applied by the force transmission member 220 to the wafer 10.

[0093] Optionally, the pressure applied by the force transmission member 220 to the wafer 10 changes in a step-like manner. Figure 5 FIG. 2 shows a pressure variation curve recorded by the first detection element 300 during the process in which the force transmission member 220 applies pressure to the wafer 10 in a stepwise manner. Figure 5, the entire process of the force transmission member 220 applying pressure to the wafer 10 is divided into a plurality of sub-processes, and the pressure applied by the force transmission member 220 to the wafer 10 in each sub-process has the same change process, specifically, the change process is: the pressure applied by the force transmission member 220 to the wafer 10 first rises from zero to the preset pressure of the corresponding sub-process at a constant rate, and then maintains the pressure for a preset time, after which the force transmission member 220 instantly releases the pressure applied to the wafer 10. In two adjacent sub-processes, the preset pressure corresponding to the latter sub-process is greater than the preset pressure corresponding to the former sub-process. Such a force application method can ensure that the initial pressure to which the wafer 10 is subjected in each sub-process is zero, eliminating the interference caused by the pressure of the previous sub-process, and by maintaining the pressure at the preset pressure, it can ensure that the corresponding preset pressure of each sub-process has a sufficient action time, thereby improving the accuracy and reliability of the test results.

[0094] To achieve the above purpose, when the force transmission member 220 instantly releases the pressure applied to the wafer 10, the retraction speed of the telescopic shaft 232 is as fast as possible. When the force application member 230 includes the hydraulic cylinder, the instantaneous retraction of the telescopic shaft 232 can be basically achieved. In addition, the constant rate, the preset pressure of each sub-process, and the pressure holding time are all set according to actual conditions. The constant rates in each sub-process are preferably equal, and the pressure holding time of each sub-process is also preferably equal.

[0095] In an alternative embodiment, the pressure applied by the force transmission member 220 to the wafer 10 in each sub-process may be varied as follows: first, the pressure of the current sub-process is increased at a constant rate to the preset pressure of the current sub-process, and then the pressure is maintained for a preset time. In two adjacent sub-processes, the preset pressure of the latter sub-process is greater than the preset pressure of the former sub-process. In another alternative embodiment, the pressure applied by the force transmission member 220 to the wafer 10 always increases at a constant rate until the wafer 10 breaks.

[0096] Furthermore, the testing method further includes controlling the force applying member 230 to stop operating after the wafer 10 is broken.

[0097] The judgment logic of whether the wafer 10 is broken may be that when the pressure detected by the first detection element 300 decreases instantaneously and then increases again, and the minimum pressure after the decrease is greater than the basic pressure, it is determined that the wafer 10 is broken.

[0098] Alternatively, when the test machine includes the second detection element 400, the judgment logic of whether the wafer 10 is broken is to use the second detection element 400 to detect whether the distance between the force transmission member 220 and the carrier 210 is less than the preset distance, and if so, it is determined that the wafer 10 is broken. Alternatively, it is determined whether the wafer 10 is broken based on the pressure detected by the first detection element 300 and the distance between the force transmission member 220 and the carrier 210 detected by the second detection element 400. That is, redundant conditions are used for judgment to improve the judgment accuracy.

[0099] It is understandable that before the next test starts, it is necessary to control the operation of the force-applying member 230 to drive the force-transmitting member 220 to move in a direction away from the carrier 210 so that the distance between the force-transmitting member 220 and the carrier 210 is greater than the thickness of the wafer 10.

[0100] Furthermore, when the test machine further includes the image acquisition element 600, the test method further includes: using the image acquisition element to acquire a crack growth video on the wafer 10. Thus, the control unit or any other suitable automated device can analyze the defects of the wafer 10 based on the crack growth video of the wafer 10, and then obtain the growth process control strategy of the wafer 10, or a technician can manually watch the crack growth video and manually analyze the defects of the wafer 10, so as to obtain the growth process control strategy of the wafer 10.

[0101] Although the present invention is disclosed as above, it is not limited thereto. Those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A test machine for testing the withstand voltage value of a wafer; characterized in that: The test machine comprises: Base; A testing mechanism, comprising a bearing member, a force transmitting member and a force applying member; the bearing member is arranged on the base and used to bear the wafer; the force transmitting member is located on a side of the bearing member away from the base, and a first tooth is arranged on a surface of the force transmitting member facing the bearing member; the force applying member is connected to the force transmitting member and is configured to drive the force transmitting member to move in a direction approaching or away from the bearing member, and to enable the force transmitting member to apply pressure to the wafer carried by the bearing member; and, The first detection element is disposed on the base and / or the carrier and is configured to detect the pressure exerted on the wafer.

2. The test machine according to claim 1, characterized in that: The end surface of the first tooth close to the bearing member is at least partially located on a first circle; a second tooth is provided on the surface of the bearing member facing the force transmission member, and the end surface of the second tooth away from the base is at least partially located on a second circle, and the second circle is of equal diameter and coaxial with the first circle; the second tooth is staggered with the first tooth in the circumferential direction of the first circle; The first detection element is arranged between the base and the supporting member.

3. The test machine according to claim 2, characterized in that: The number of the first teeth is at least one, and the number of the second teeth is at least three.

4. The test machine according to claim 2, characterized in that: The testing mechanism also includes a limit member, which is disposed on the base and / or the supporting member; the limit member is arranged around the axis of the first circle, and the limit member has a preset position on the surface of the side facing the axis of the first circle, and the preset position is located on a third circle; the third circle is coaxial with the first circle, the diameter of the third circle is larger than the diameter of the first circle, and the third circle is coplanar with the end face of the second tooth away from the base.

5. The test machine according to claim 2, characterized in that: The test machine further comprises a frame, which is arranged on the base and at least partially located on a side of the force transmission member away from the bearing member; The force-applying member includes a force-generating part, a telescopic shaft, a first connecting member and a second connecting member; the force-generating part is connected to the frame and is located on the side of the force-transmitting member away from the bearing member; the telescopic shaft is connected to the force-generating part and is coaxially arranged with the first circle; the first connecting member is perpendicular to the telescopic shaft, and the first connecting member is connected to the side of the telescopic shaft away from the force-generating part; a plurality of the second connecting members all extend along the axial direction of the telescopic shaft, and a plurality of the second connecting members are spaced apart around the axis of the telescopic shaft; one end of the second connecting member is connected to the first connecting member, and the other end is connected to the force-transmitting member.

6. The test machine according to claim 2, characterized in that: The testing machine also includes an image capture element, which is arranged on a side of the force transmitting member facing away from the supporting member, and the field of view of the image capture element covers an area defined by a third circle, the third circle is coaxial with the first circle, the diameter of the third circle is larger than the diameter of the first circle, and the third circle is coplanar with an end of the second tooth away from the base.

7. The test machine according to claim 6, characterized in that: The force transmission member is a circular ring structure coaxial with the first circle; the lens of the image acquisition element is coaxially arranged with the force transmission member.

8. The test machine according to claim 6 or 7, characterized in that: The force transmission member is a transparent structural member.

9. The test machine according to claim 1, characterized in that: The testing machine further includes a second detection element, which is configured to detect whether the distance between the force transmission member and the support member is less than or equal to a preset distance.

10. A wafer testing method, performed based on the testing machine according to any one of claims 1 to 9, characterized in that: The test method includes: placing a wafer on the carrier and making the target area of ​​the wafer correspond to the first tooth; Controlling the force applying member to operate and driving the force transmitting member to move in a direction close to the supporting member, so that the first tooth contacts the target area of ​​the wafer, and then the force transmitting member applies pressure to the target area of ​​the wafer until the wafer breaks; The pressure applied by the force transmission member to the wafer when the wafer is broken is obtained through the first detection element as the withstand pressure value of the wafer at the target area.

11. The wafer testing method according to claim 10, characterized in that: The pressure applied by the force transmission member to the wafer changes in a step-like manner; The process of the force transmission member applying pressure to the wafer includes a plurality of sub-processes; in any of the sub-processes, the pressure applied by the force transmission member to the wafer first increases uniformly from zero to a preset pressure of the corresponding sub-process, then maintains the pressure for a preset time, and finally the force transmission member instantly releases the pressure applied to the wafer; In two adjacent sub-processes, the preset pressure corresponding to the latter sub-process is greater than the preset pressure corresponding to the former sub-process.

12. The wafer testing method according to claim 10, characterized in that: The force transmission member and the bearing member are arranged in a vertical direction, and the bearing member is below the force transmission member; the first detection element is arranged between the base and the bearing member; The wafer testing method further includes: When the pressure detected by the first detection element decreases instantaneously and then increases again, and the minimum pressure after the decrease is greater than the sum of the gravity of the carrier and the gravity of the wafer, the force applying member is controlled to stop running.

13. The wafer testing method according to claim 10 or 12, characterized in that: The test machine also includes a second detection element; The wafer testing method further includes: The second detection element is used to detect whether the distance between the force transmission member and the support member is less than or equal to a preset distance. If so, the force application member is controlled to stop running; the preset distance is less than the thickness of the wafer.

14. The wafer testing method according to claim 10, characterized in that: The test machine also includes an image acquisition component; The test method also includes: The image acquisition element is used to acquire a video of crack growth on the wafer.

15. The wafer testing method according to claim 10, characterized in that: The distance from any point on the target area to the edge of the wafer is no more than 20 mm.

Images