Measuring device

Abstract

The utility model relates to the technical field of semiconductor detection, in particular to a measuring device. By arranging the light source assembly, a reflected light beam generated by the surface of the to-be-detected wafer can be split into two beams of reflected light, and imaging is carried out based on the two beams of reflected light, so that the scanning view field is enlarged, and the precision can be doubled under the same yield; and by arranging the adjusting assembly, the spatial position of the light source and the spatial position of the optical assembly can be adjusted, the degrees of freedom are relatively decoupled, and the adjusting mode is convenient.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor detection, and in particular to a measuring device. BACKGROUND

[0002] In the process of manufacturing semiconductor wafers, with the increasing demand and the progress of technology, wafer level packaging is more and more common compared with traditional packaging, and the packaging process inevitably involves multi-layer stacking or ball mounting process, which mostly needs to be judged whether there are defects or defects by detecting the spatial morphology, so the demand for 3D measurement in the wafer detection process is also increasing.

[0003] Laser triangulation is a common wafer 3D measurement method. Laser triangulation is a method that uses the law of optical reflection in the process of light space propagation and the principle of similar triangles to form a similar relationship between the object space and the image space of the receiving lens, and calculates the three-dimensional information by using the edge angle relationship. This method is a non-contact measurement method that does not damage the product surface, but its measurement accuracy is related to many factors, such as the selection of the camera, the stability of the laser emitter, the stability of the entire system, the scanning interval, etc. In the wafer online detection scene, yield and accuracy are usually contradictory indicators. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a measuring device that can increase the scanning field of view, thereby doubling the accuracy at the same yield, and has high adjustment freedom and relative decoupling between each degree of freedom, and the adjustment method is convenient.

[0005] In a first aspect, an embodiment of the present application provides a measuring device, comprising a light source and a light source assembly arranged on a back plate, the light source is used to generate a laser incident beam of a target attitude to the surface of a to-be-detected object, and form a reflected light beam via the surface of the to-be-detected object; the optical assembly is used to receive the reflected light beam and form two sub-beams with the same optical path, and the sub-beams enter the corresponding imaging assembly; further comprising an adjustment assembly, which is used to adjust the spatial position of the light source to make the laser incident beam be projected in the target attitude, and is also used to adjust the spatial position of the optical assembly to make the reflected light beam be completely received.

[0006] In some specific implementation manners, the optical assembly comprises at least one beam splitter arranged on the path of the reflected light beam, which is used to split the reflected light beam, and the two split sub-beams are received by the imaging assembly arranged at the end of the corresponding lens barrel.

[0007] In some specific implementation manners, the adjustment assembly comprises a light source adjustment assembly for adjusting the spatial position of the light source, and the spatial position of the light source comprises a translational position relative to the to-be-detected object and a rotational angle position.

[0008] In some embodiments, the adjusting assembly comprises a lens barrel adjusting assembly for adjusting the spatial position of the optical assembly, the spatial position of the optical assembly comprising a translational position relative to the object to be detected and a rotational angle position.

[0009] In some embodiments, the light source is fixed to a connecting plate by a fixing assembly, the connecting plate being fixedly arranged on the back plate; the light source adjusting assembly comprises a moving assembly on the connecting plate, the moving assembly comprising at least one horizontally arranged moving member and one vertically arranged moving member, the connecting plate being moved horizontally and vertically by external force.

[0010] In some embodiments, the light source is fixed to a first connecting plate by a fixing assembly, the first connecting plate being arranged on a second connecting plate, the second connecting plate being arranged on the back plate; the light source adjusting assembly comprises two moving assemblies arranged on the first connecting plate and the second connecting plate, the moving assemblies comprising horizontally arranged or vertically arranged moving members, the moving members of the two moving assemblies being arranged in different directions.

[0011] In some embodiments, the moving member comprises a screw, the screw moving the connecting plate in the force application direction by external force.

[0012] In some embodiments, the fixing assembly comprises a sleeve and a connecting seat extending laterally along the sleeve, the connecting seat extending axially along the light source and having a protrusion, the protrusion being rotated by external lateral force to change the rotational angle position of the fixing assembly and the light source.

[0013] In some embodiments, the lens barrel is arranged on a first mounting plate, the first mounting plate being arranged on a second mounting plate, the second mounting plate being arranged on the back plate; a moving groove is arranged on the second mounting plate along the vertical direction, the first mounting plate being arranged in the moving groove, the first mounting plate being moved in the direction of the moving groove by external force.

[0014] In some embodiments, a fixing block is arranged on each side of the second mounting plate, and two adjusting blocks are arranged on the first mounting plate, the two adjusting blocks being arranged on the same side of the fixing block and being symmetrically arranged relative to the fixing block; a through hole is arranged on each of the two adjusting blocks and a screw is arranged in the through hole, the screw being selectively in contact with the fixing block, the first mounting plate being moved by applying force to the screw to abut against the fixing block.

[0015] In some specific implementation manners, two rotary knob fixing seats are arranged on the back plate, and the two rotary knob fixing seats are arranged on the same side of the fixing block and symmetrically relative to the fixing block; a through hole is formed in each of the two rotary knob fixing seats and a screw is arranged in the through hole, the screw is selectively in contact with any one side of the fixing block, and the second mounting plate is driven to rotate by applying a force in a corresponding direction to the screw and abutting against the fixing block.

[0016] The embodiment of the present application brings the following beneficial effects:

[0017] The embodiment of the present application provides a measurement device, by arranging a light source assembly, the reflected light beams generated through the surface of a wafer to be detected can be split to form two reflected light beams, and imaging is performed based on the two reflected light beams, so that the scanning field of view is increased, and the precision can be doubled under the same yield; and by arranging an adjusting assembly, the spatial position of the light source and the spatial position of the optical assembly can be adjusted, and each degree of freedom is relatively decoupled, and the adjusting mode is convenient.

[0018] Other features and advantages of the present disclosure will be described in the following description, or some features and advantages can be inferred from the description or determined without doubt, or can be known by implementing the above-mentioned technologies of the present disclosure.

[0019] In order to make the above-mentioned purposes, features and advantages of the present disclosure more obvious and easy to understand, the following preferred embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0021] Figure 1 The measurement device provided by the embodiment of the present application is shown in the overall structure diagram;

[0022] Figure 2 The optical path structure schematic diagram provided by the embodiment of the present application is shown in the optical path structure schematic diagram;

[0023] Figure 3 One structure schematic diagram of the light source adjusting assembly provided by the embodiment of the present application is shown in the optical path structure schematic diagram;

[0024] Figure 4 Another structure schematic diagram of the light source adjusting assembly provided by the embodiment of the present application is shown in the optical path structure schematic diagram;

[0025] Figure 5The optical assembly structure schematic diagram provided by the embodiment of the present application is shown in the figure;

[0026] Figure 6 The optical assembly adjustment structure schematic diagram provided by the embodiment of the present application is shown in the figure;

[0027] Figure: 10-measuring device; 20-back plate; 30-wafer;

[0028] 11-light source; 12-optical assembly; 13-adjustment assembly;

[0029] 111-laser light source; 112-fixing assembly; 113-first connecting plate; 114-second connecting plate; 115-moving piece; 116-sleeve; 117-connecting seat; 118-bump;

[0030] 121-spectroscope; 122-reflector; 123-lens barrel; 124-first mounting plate; 125-second mounting plate; 126-lens barrel adjustment assembly; 127-fixing block; 128-adjusting block; 129-rotary fixing seat. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the embodiment of the present application more clear, the technical scheme of the present application will be described clearly and completely below in combination with the drawings. Obviously, the described embodiment is a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0032] The measuring device provided by the embodiment of the present application is applied to semiconductor optical detection, wherein the semiconductor product is a wafer product, including a patterned wafer and a non-patterned wafer. In other embodiments, it can also be applied to other precision component products. The measuring device is used for projecting an illumination light beam on the surface of the above product, and through other image acquisition devices, the surface image of the product is acquired based on the illumination light beam, and the surface of the above product is analyzed to determine whether the surface has visible defects, damages or other undesirable characteristics.

[0033] Alternatively, the measuring device in the embodiment can also be used in dark field / bright field defect detection scenarios, by projecting an illumination light beam on the surface of the product through the illumination device, and through the sensor, the scattered light / reflected light of the product surface is acquired, and according to the distribution characteristics of the scattered light / reflected light, it is determined whether the product surface has defects and the type of defects.

[0034] Wherein, for optical measurement using laser triangulation method, using the law of optical reflection in the process of light space propagation and the principle of similar triangles, the object space and the image space at the receiving end form a similar relationship, and the three-dimensional information is calculated by using the edge angle relationship. In the prior art, in order to consider the requirement of accuracy, a single receiving end is generally used to ensure the accuracy control of the overall optical propagation process and the accuracy control of the optical mechanical system.

[0035] But in this embodiment, in order to improve the overall processing efficiency of the optical system and thus improve the yield, a measuring device is provided, which can adjust the relative positions of multiple key device components to ensure the accuracy of measurement and improve the working efficiency and thus improve the overall process yield by setting two groups of receiving ends and adjusting components corresponding to the light source and the receiving end.

[0036] Wherein, referring to 1, the measuring device provided in this embodiment includes a back plate for fixedly connecting the measuring device with the optical mechanical system, and a light source and an optical component are arranged on the back plate. The light source in this embodiment is a laser light source, which is used to generate a laser incident beam of target attitude to the surface of the object to be detected and form a reflected beam. Wherein, the reflected beam is received by the optical component. In this embodiment, after the optical component receives the reflected beam, the reflected beam is split to form two sub-beams with the same optical path, and the sub-beams enter the corresponding imaging components.

[0037] Wherein, the target attitude has an incident angle with the surface of the object to be detected, and the incident angle is 45°, and the height of the light source relative to the object to be detected and the incident point of the incident beam on the object to be detected meet the pre-setting requirements.

[0038] The object to be detected in this embodiment is a wafer, including a patterned wafer and a non-patterned wafer and a silicon wafer after cutting. The imaging component in this embodiment is a 3D camera.

[0039] As can be seen from the above, the measuring device provided in this embodiment can split the reflected beam by setting the optical component, thereby increasing the scanning field of view, so that the accuracy is doubled under the same yield, or the yield is doubled under the same accuracy.

[0040] In this embodiment, for how the optical component splits the reflected beam and enters the imaging component, please refer to Figure 2 The optical propagation path corresponding to the measuring device provided in this embodiment and the optical device arranged in the optical component.

[0041] Specifically, the optical assembly includes at least one beam splitter arranged in the path of the reflected light beam, for splitting the reflected light beam to form a first sub-beam and a second sub-beam. The first sub-beam enters the first lens barrel along the original propagation direction, and the second sub-beam enters the second lens barrel along a propagation direction perpendicular to the original propagation direction after being split.

[0042] In the first lens barrel and the second lens barrel, a plurality of functional devices for shaping and focusing the light are arranged, which will not be described in detail in this embodiment and can be configured according to actual optical requirements.

[0043] Further, in order to realize the compactness of the device structure in this embodiment, a mirror is further arranged in the path of the second sub-beam to change the propagation direction of the second sub-beam to be parallel to the direction of the first sub-beam. Moreover, the total optical path of the two sub-beams is the same, and the imaging effect is the same.

[0044] The measurement device provided in the above embodiment can form two parallel reflected light beams by arranging the beam splitter and the mirror, and the two reflected light beams are received by the imaging assembly, thereby increasing the scanning field of view.

[0045] Moreover, in order to ensure that the light source and the optical assembly in the measurement device can be adjusted in attitude and adjusted when a position error occurs, an adjusting assembly is further configured in this embodiment, for adjusting the spatial position of the light source to make the laser incident light beam transmit in a target attitude, and adjusting the spatial position of the optical assembly to make the reflected light beam be completely received.

[0046] The adjusting assembly includes a lens barrel adjusting assembly for adjusting the spatial position of the optical assembly, and a light source adjusting assembly for adjusting the spatial position of the light source. Specifically, the adjustment of the spatial position of the optical assembly includes the translational attitude of the optical assembly relative to the wafer to be detected and the rotational angle position of the optical assembly relative to the wafer; and the adjustment of the spatial position of the light source includes the translational position of the light source relative to the wafer to be detected and the rotational angle position of the light source relative to the wafer.

[0047] Specifically, the structure of the light source adjusting assembly can be referred to Figure 3 , which includes a fixing assembly for fixing the laser source, and a connecting plate connected to the fixing assembly, wherein the connecting plate is fixed to the back plate by a fixing member, which is generally a bolt, and can realize the fixing and dismounting of the connecting plate.

[0048] In this embodiment, in order to achieve the change of translation position of the laser source relative to the object to be tested, i.e., the wafer, a moving component is provided on the connecting plate. The moving component includes at least one horizontally arranged moving part and one vertically arranged moving part. An external force is applied to the two moving parts to drive the connecting plate to move horizontally and vertically.

[0049] In this embodiment, the movable component includes a screw, one end of which is connected to the side end of the connecting plate. The screw can drive the connecting plate to move along the force direction by external force.

[0050] Furthermore, in this embodiment, to avoid interference errors caused by lateral and vertical movement, the connecting plate includes a first connecting plate and a second connecting plate. The light source is fixed to the first connecting plate via a fixing assembly. The first connecting plate is disposed on the second connecting plate, and the second connecting plate is disposed on the back plate. Furthermore, a laterally positioned moving member and a vertically positioned moving member are respectively disposed on the first and second connecting plates, and the two moving members have different directions; that is, the first and second connecting plates can respectively achieve lateral and vertical movement.

[0051] participate Figure 4 In this embodiment, the fixing component includes a sleeve, and a connecting seat extends laterally from the sleeve. A protrusion extends along the light source axis from the connecting seat, and the protrusion, through an external lateral force, causes the fixing component and the light source to rotate at different angles. In this embodiment, the sleeve is connected to the first connecting plate via a transition connecting plate, and an arc-shaped through hole is formed between the connecting seat and the transition connecting plate. This through hole is used to pass through a fixing bolt, thus forming a connection structure between the connecting seat and the transition connecting plate. Specifically, an external force is applied to the protrusion, causing the protrusion to move the connecting seat. The connecting seat is fixed to the connecting plate in the direction of the applied force and cannot move laterally. Furthermore, the arc-shaped through hole between the connecting seat and the transition connecting plate allows the force to be applied along its arc shape, thus changing the direction of the external force and causing rotational movement.

[0052] The light source adjustment component in this embodiment, through the aforementioned structure, enables the laser light source to perform corresponding translational movement and rotation angle adjustments. For the structure and adjustment mechanism of the lens barrel adjustment component, please refer to [reference needed]. Figure 5 As shown. The lens barrel is mounted on a first mounting plate, the first mounting plate is mounted on a second mounting plate, and the second mounting plate is mounted on a back plate. The positions of the first and second mounting plates relative to the back plate are adjusted by a lens barrel adjustment assembly, thereby causing a corresponding change in the position of the lens barrel relative to the back plate, and consequently, a corresponding change in the spatial position of the lens barrel relative to the wafer to be inspected.

[0053] In the embodiment, the lens barrel adjusting assembly is used to adjust the spatial position of the optical assembly, specifically, to adjust the translational position and the rotational angle position of the optical assembly relative to the wafer to be detected. The translational position of the optical assembly refers to the vertical movement relative to the height position of the wafer to be detected. The main structural unit of the optical assembly in the embodiment is the lens barrel, that is, the devices in the optical assembly are mounted in the lens barrel, and the number of the lens barrels in the embodiment is two and the lens barrels are connected by the connecting piece and arranged in parallel. Therefore, the adjustment of the optical assembly in the embodiment is the adjustment of the lens barrel.

[0054] Specifically, as shown in Figure 6 The lens barrel in the embodiment is arranged on the first mounting plate, the first mounting plate is arranged on the second mounting plate, and the second mounting plate is arranged on the back plate. The second mounting plate is vertically provided with a moving groove, and the first mounting plate is arranged in the moving groove and can move vertically along the moving groove based on an external force. That is, the vertical movement of the lens barrel in the embodiment can be realized by applying a force to the first mounting plate, and the movement of the first mounting plate drives the movement of the lens barrel.

[0055] The second mounting plate is provided with a fixed block on both sides, and the first mounting plate is provided with two groups of adjusting blocks. Each group of adjusting blocks includes two adjusting blocks and is symmetrically arranged with the fixed block. Through holes are formed in the two adjusting blocks and two screws pass through the through holes. The two screws respectively contact the two sides of the fixed block. By applying a force to any one of the screws and abutting against the fixed block, the first mounting plate is correspondingly moved, so that the first mounting plate drives the vertical movement of the lens barrel.

[0056] The adjustment of the rotational angle of the optical assembly in the embodiment is realized by arranging two knob fixing seats symmetrically with the fixed block on the back plate. Through holes are formed in the two knob fixing seats and corresponding screws are arranged in the through holes. The screws contact and abut against any side of the fixed block, and based on the inclined waist type opening hole on the back plate, by applying a corresponding vertical force to the screw and abutting against the fixed block, the second mounting plate is driven to rotate, so that the angle of the second mounting plate, the first mounting plate and the lens barrel relative to the back plate is adjusted.

[0057] In summary, the embodiment of the present application provides a measurement device. By arranging the light source assembly, two reflected light beams can be formed by splitting the reflected light beam generated by the surface of the wafer to be detected, and imaging is performed based on the two reflected light beams, so as to increase the scanning field of view and improve the precision by one time under the same yield. By arranging the adjusting assembly, the spatial position of the light source and the spatial position of the optical assembly can be adjusted, and the degrees of freedom are relatively decoupled, and the adjusting mode is convenient.

[0058] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0059] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A metrology device, characterized in that, The application relates to a light source and optical assembly arranged on a back plate, the light source is used for generating a laser incident light beam with a target posture to the surface of an object to be detected, and forming a reflected light beam via the surface of the object to be detected; the optical assembly is used for receiving the reflected light beam and forming two sub-beams with the same optical path, which enter corresponding imaging assemblies; the adjusting assembly is used for adjusting the spatial position of the light source to make the laser incident light beam project in the target posture, and is also used for adjusting the spatial position of the optical assembly to make the reflected light beam be completely received.

2. The apparatus of claim 1, wherein The optical assembly comprises at least one beam splitter arranged on the path of the reflected light beam, which is used for splitting the reflected light beam, and two sub-beams after splitting are received by the imaging assemblies arranged at the end of corresponding lens barrels.

3. The apparatus of claim 1, wherein, The adjusting assembly comprises a light source adjusting assembly used for adjusting the spatial position of the light source, which comprises a translational position relative to the object to be detected and a rotational angle position.

4. The apparatus of claim 2, wherein, The adjusting assembly comprises a lens barrel adjusting assembly used for adjusting the spatial position of the optical assembly, which comprises a translational position relative to the object to be detected and a rotational angle position.

5. The apparatus of claim 3, wherein, The light source is fixed on a connecting plate through a fixing assembly, and the connecting plate is fixedly arranged on the back plate; the light source adjusting assembly comprises a moving assembly on the connecting plate, the moving assembly comprises at least one horizontally arranged moving piece and one vertically arranged moving piece, and the connecting plate is driven to move horizontally and vertically by external force.

6. The apparatus of claim 5, wherein, The light source is fixed on a first connecting plate through a fixing assembly, the first connecting plate is arranged on a second connecting plate, and the second connecting plate is arranged on the back plate; the light source adjusting assembly comprises two moving assemblies arranged on the first connecting plate and the second connecting plate, the moving assemblies comprise moving pieces arranged horizontally or vertically, and the moving pieces on the two moving assemblies are arranged in different directions.

7. The apparatus of claim 5 or 6, wherein The moving piece comprises a screw rod, the screw rod drives the connecting plate to move in the force direction by external force.

8. The apparatus of claim 5, wherein, The fixing assembly comprises a sleeve and a connecting seat extending laterally along the sleeve, the connecting seat extends outwardly along the axial direction of the light source and has a protrusion, and the protrusion drives the fixing assembly and the light source to change the rotational angle position by external horizontal force.

9. The apparatus of claim 4, wherein, The lens barrel is arranged on a first mounting plate, the first mounting plate is arranged on a second mounting plate, the second mounting plate is arranged on the back plate, and a moving groove is arranged on the vertical two sides of the second mounting plate, the first mounting plate is arranged in the moving groove, and the first mounting plate is driven to move in the direction of the moving groove by external force.

10. The apparatus of claim 9, wherein, The fixed block is arranged on both sides of the second mounting plate, two adjusting blocks are arranged on the first mounting plate, the two adjusting blocks are arranged on the same side of the fixed block, and the two adjusting blocks are symmetrically arranged relative to the fixed block; and a through hole is formed in the two adjusting blocks and a screw is arranged in the through hole, and the screw is selectively in contact with the fixed block, and the first mounting plate is driven to move by applying a force to the screw and abutting against the fixed block.

11. The apparatus of claim 10, wherein, The two knob fixing seats are arranged on the back plate, the two knob fixing seats are arranged on the same side of the fixed block and symmetrically relative to the fixed block; a through hole is formed in the two knob fixing seats and a screw is arranged in the through hole, and the screw is selectively in contact with any one side of the fixed block, and the second mounting plate is driven to rotate by applying a force to the screw in a corresponding direction and abutting against the fixed block.

Images