An independent automatic object-to-object focal length and transmitted light focal length adjustment structure for infrared double-sided overlay.

Abstract

This invention proposes an independent automatic adjustment structure for the focal length of the measured object and the focal length of the transmitted light in infrared double-sided overlay etching. The structure includes: a stage for supporting the wafer, which is a hollow structure connected to the output end of a stage focusing unit; the stage focusing unit is movable along a base and in the Z-direction; an imaging optical path unit disposed above the stage; and a transmitted light source disposed below the hollow region of the stage and connected to the output end of the transmitted light focusing unit; the transmitted light focusing unit is movable along a base plate and in the Z-direction, and the base plate is connected to the base. This invention enables independent adjustment of the measured object distance and the transmitted light focal length.

Description

Technical Field

[0001] This invention belongs to the field of double-sided engraving technology, and particularly relates to an independent automatic object focal length and transmitted light focal length adjustment structure for infrared double-sided engraving. Background Technology

[0002] Double-sided lithography machines will have the problem of imprint position deviation during operation (or other wafers or similar products with upper and lower alignment marks). However, it is very difficult to accurately inform the lithography machine (or similar upper and lower alignment equipment) of the deviation value. This requires the relevant measurement equipment to have high precision and high stability, and to overcome the problem of different focal lengths of the upper and lower layers with great thickness. Summary of the Invention

[0003] The purpose of this invention is to provide an independent automatic adjustment structure for the focal length of the measured object and the focal length of the transmitted light in infrared double-sided overlay, enabling independent adjustment of the object distance and the focal length of the transmitted light. The technical solution adopted is as follows:

[0004] An independent automatic object-to-surface focal length and transmitted light focal length adjustment structure for infrared double-sided overlay includes:

[0005] Stage 1, which is used to support the wafer, is a hollow structure and is connected to the output end of stage focusing unit 5.

[0006] The stage focusing unit 5 is movable along the base 4 and in the Z direction;

[0007] Imaging optical path unit 2 is disposed above stage 1;

[0008] And the transmitted light source 3 is located below the hollow area of ​​the stage 1 and is connected to the output end of the transmitted light focusing unit 6.

[0009] The transmitted light focusing unit 6 is movable along the base plate 7 and in the Z direction, and the base plate 7 is connected to the base 4.

[0010] Preferably, the base 4 includes:

[0011] Plate 40, and plate 41 connected to plate 40; plate 41 extends upward from plate 40 along the Z direction.

[0012] The base plate 7 includes: a first plate 70 and a second plate 71 connected to the first plate 70; the second plate 71 extends upward from the first plate 70 along the Z direction.

[0013] The focusing unit 5 of the stage forms a Z-axis sliding pair with the front surface of the second plate 41.

[0014] The transmitted light focusing unit 6 is located within the area enclosed by the stage focusing unit 5, and forms a second Z-axis sliding pair with the second plate 71.

[0015] Preferably, the first Z-axis sliding pair includes:

[0016] Guide rail and slider that mates with the guide rail;

[0017] The guide rail is mounted on plate 41, and the slider is mounted on the focusing unit 5 of the stage.

[0018] Preferably, the second Z-axis sliding pair includes:

[0019] Slide rail one, which is set on plate 70, has a dovetail groove on its outer surface along the X direction;

[0020] The second slide rail, which mates with the dovetail groove, is located on the transmission light focusing unit 6.

[0021] Preferably, the stage focusing unit 5 includes:

[0022] Mounting base 50 is located on plate 40 and behind plate 71. Its front end passes forward through plate 41 and sliding plate 55.

[0023] Motor 51, whose housing is mounted on mounting base 50, has its output shaft connected to ball screw 51.

[0024] The first ball screw is rotatably mounted on the first mounting base 50, and its first nut 52 is connected to the first connecting bracket 53.

[0025] The first connecting frame 53 includes two free ends distributed along the X direction, and windows for the first connecting frame 53 to pass through are opened on both the second plate 41 and the first sliding plate 55.

[0026] And the first wedge unit 54, the inner surface of its lower wedge block is connected to one free end of the first connecting frame 53, the rear end face of its upper wedge block is connected to the front surface of the same first slide plate 55, and a first Y-axis sliding pair is formed between its lower wedge block and plate 40.

[0027] The first sliding plate 55 and the second sliding plate 41 form the first Z-axis sliding pair;

[0028] An inclined sliding pair is formed between the upper and lower wedge blocks of the first wedge unit 54.

[0029] Preferably, the first Y-axis sliding pair and the tilting sliding pair have the same structure as the first Z-axis sliding pair.

[0030] Preferably, the transmitted light focusing unit 6 includes:

[0031] Mounting base 60 is located on plate 70 and in front of plate 71;

[0032] Motor No. 2 61, whose housing is set on Mount No. 2 60, and whose output shaft is connected to Ball Screw No. 2;

[0033] The second ball screw is rotatably mounted on the second mounting base 60, and its second nut 62 is connected to the second connecting bracket 63;

[0034] A pair of second wedge units 64, the lower wedge blocks of which are connected to the same lower sliding plate 67, the lower sliding plate 67 and the first plate 70 form a first Y-axis sliding pair, and the outer surface of the lower wedge block of one of the second wedge units 64 is connected to the second connecting frame 63.

[0035] The rear end faces of the upper wedge blocks of the pair of second wedge units 64 are connected to the front surface of the same second sliding plate 65; an inclined sliding pair is formed between the upper wedge blocks and the lower wedge blocks of the second wedge unit 64;

[0036] The second sliding plate 65 and the second plate 71 form the second Z-axis sliding pair;

[0037] The mounting plate 66 is connected to the upper wedge block of a pair of second wedge units 64 and is located above the lower slide plate 67, on which the transmission light source 3 is provided.

[0038] Preferably, the stage 1 includes:

[0039] The base 10 is connected to the output end of the stage focusing unit 5;

[0040] The fixed rail 11, the lower guide rail 12 and the upper guide rail 13 are slidably connected from bottom to top, and the fixed rail 11 is fixedly connected to the base 10.

[0041] The lower guide rail 12 is connected to the output end of the Y-axis module via the Y-axis connector 8;

[0042] The upper guide rail 13 is connected to the output end of the X-axis module via the X-axis connector 9;

[0043] Both the Y-axis module and the X-axis module are mounted on the base 10.

[0044] Preferably, the lower guide rail 12 and the upper guide rail 13 are slidably connected by an inner slide rail 14 and an outer slide rail 15;

[0045] The inner slide rail 14 is disposed on the lower guide rail 12, and the outer slide rail 15 is disposed on the upper guide rail 13.

[0046] Compared with the prior art, the advantages of the present invention are:

[0047] The stage's vertical structure ensures that the wafer is positioned on the required imaging focal plane of the camera; the transmission light source is designed to automatically adjust vertically without affecting the independent movement of the stage. Attached Figure Description

[0048] Figures 1-2 A diagram of an equipment equipped with an independent automatic object-to-measure focal length and transmitted light focal length adjustment structure with infrared double-sided overlay.

[0049] Figures 3-4 A three-dimensional view of an independent automatic measurement object focal length and transmitted light focal length adjustment structure with infrared double-sided overlay.

[0050] Figure 5 This is a schematic diagram showing the relative positions of the stage, the transmitted light source, the stage focusing unit, and the transmitted light focusing unit.

[0051] Figure 6 This is a schematic diagram showing the relative positions of the base plate, platform, and base.

[0052] Figure 7 This diagram illustrates the connection method between connector No. 1 and nut No. 1.

[0053] Figure 8 This is a structural diagram of the focusing unit of the stage.

[0054] Figure 9 This is a schematic diagram showing the relative position of the No. 1 mounting base in the focusing unit of the stage to other components.

[0055] Figure 10 This is a diagram showing the relative position of the first wedge-shaped unit in the stage focusing unit and the transmitted light focusing unit.

[0056] Figure 11 This is a diagram showing the mounting plate in the transmitted light focusing unit, illustrating its mounting method.

[0057] Figure 12 This diagram illustrates the relative position of the mounting plate and the lower sliding plate in the transmission light focusing unit.

[0058] Figure 13 This is a structural diagram of the transmitted light focusing unit;

[0059] Figure 14 This is the structure of the second Z-axis sliding pair;

[0060] Figures 15-16 This is a three-dimensional view of the stage;

[0061] Figure 17 This is an exploded view of the stage.

[0062] Among them, 1-stage, 10-base, 11-fixed rail, 12-lower guide rail, 13-upper guide rail, 14-inner slide rail, 15-outer slide rail;

[0063] 2-Optical path unit, 3-Transmission light source,

[0064] 4-Base, 40-Plate 1, 42-Plate 2;

[0065] 5-Stage focusing unit, 50-Mounting base No. 1, 51-Motor No. 1, 52-Nut No. 1, 53-Connecting frame No. 1, 54-Wedge unit No. 1, 55-Slide plate No. 1;

[0066] 6-Transmitted light focusing unit, 60-Mounting base No. 2, 61-Motor No. 2, 62-Nut No. 2, 63-Connecting bracket No. 2, 64-Wedge unit No. 2, 65-Slide plate No. 2, 66-Mounting plate, 67-Lower slide plate;

[0067] 7 - base plate, 70 - No. 1 plate, 71 - No. 2 plate;

[0068] 8-Y-direction connector, 9-X-direction connector. Detailed Implementation

[0069] The following is a more detailed description of an independent automatic object-to-surface focal length and transmitted light focal length adjustment structure for infrared double-sided overlay, with reference to schematic diagrams. Preferred embodiments of the invention are shown. It should be understood that those skilled in the art can modify the invention described herein while still achieving its advantageous effects. Therefore, the following description should be understood as being of general knowledge to those skilled in the art and is not intended to limit the invention.

[0070] like Figures 1-17 An independent automatic measurement object focal length and transmitted light focal length adjustment structure for infrared double-sided overlay, comprising:

[0071] Stage 1, which is used to support the wafer, is a hollow structure and is connected to the output end of stage focusing unit 5; the wafer covers the hollow area.

[0072] The stage focusing unit 5 is movable along the base 4 and in the Z direction;

[0073] Imaging optical path unit 2 (prior art) is disposed above stage 1 and includes a microscope camera, an upright illumination optical path, and an imaging lens. The upright illumination optical path includes an orthogonal light inlet. Specifically, imaging optical path unit 2 is fixedly mounted on the gantry beam.

[0074] And the transmitted light source 3 is located below the hollow area of ​​the stage 1 and is connected to the output end of the transmitted light focusing unit 6.

[0075] The transmission light focusing unit 6 can move along the base plate 7 and in the Z direction. The base plate 7 is connected to the base 4 by fasteners.

[0076] The measured object distance can be understood as follows: this distance will be specific depending on the objective lens configuration; if the distance is incorrect, the image will be blurry.

[0077] The focal length of transmitted light can be understood as follows: when the light path is configured well, the light source will be at a specific distance. If the distance is off, it will cause the light to be scattered and the illumination effect will be poor.

[0078] In this embodiment, the output end of the stage focusing unit 5 is the first sliding plate 55; the output end of the transmitted light focusing unit 6 is the mounting plate 66.

[0079] The "forward" direction refers to the direction along the Y-axis, towards plate 71.

[0080] The "outer" direction refers to the direction along the X direction, away from plate 71.

[0081] like Figures 9-10 As shown, the base 4 includes:

[0082] Plate 1 40, and Plate 2 41 connected to Plate 1 40; Plate 2 41 extends upward from Plate 1 40 along the Z direction;

[0083] The base plate 7 includes: a first plate 70 and a second plate 71 connected to the first plate 70; the second plate 71 extends upward from the first plate 70 along the Z direction.

[0084] The stage focusing unit 5 forms a Z-axis sliding pair with the front surface of plate 41.

[0085] The transmission light focusing unit 6 is located within the area enclosed by the stage focusing unit 5, and forms a second Z-axis sliding pair with the second plate 71.

[0086] like Figure 10 As shown, the first Z-axis sliding joint includes:

[0087] Guide rail and slider that mates with the guide rail;

[0088] The guide rail is mounted on plate 41 by fasteners, and the slider is mounted on the focusing unit 5 of the stage by fasteners.

[0089] like Figure 11 , Figure 14 As shown, the second Z-axis sliding joint includes:

[0090] Slide rail 1 is mounted on plate 70 by fasteners, and a dovetail groove is formed on its outer surface along the X direction.

[0091] The second slide rail, which mates with the dovetail groove, is mounted on the transmission light focusing unit 6 via fasteners.

[0092] like Figure 8 , Figure 10 As shown, the stage focusing unit 5 includes:

[0093] Mounting base 50 is mounted on plate 40 by fasteners and located behind plate 71. Its front end passes forward through plate 41 and sliding plate 55.

[0094] Motor 51 has its housing mounted on mounting base 50 and its output shaft connected to ball screw 51 via a coupling.

[0095] The first ball screw is rotatably mounted on the first mounting base 50 via a bearing, and its first nut 52 is connected to the first connecting bracket 53; in this embodiment, the first connecting bracket 53 is embedded in the first nut 52, as shown below. Figure 8 As shown.

[0096] The first connecting frame 53 includes two free ends distributed along the X direction, and windows for the first connecting frame 53 to pass through are opened on both the second plate 41 and the first sliding plate 55.

[0097] The first wedge unit 54 has its lower wedge block inner surface connected to one free end of the first connecting frame 53, and the rear end face of its upper wedge block is connected to the front surface of the same first sliding plate 55. A first Y-axis sliding pair is formed between its lower wedge block and plate 40. In this embodiment, the first wedge unit 54 and the first sliding plate 55 are connected by fasteners.

[0098] The first skateboard 55 and the second skateboard 41 are slidably connected;

[0099] An inclined sliding pair is formed between the upper and lower wedge blocks of the first wedge unit 54.

[0100] like Figure 10 As shown, the structure of the first Y-axis sliding pair and the tilting sliding pair are the same as that of the first Z-axis sliding pair.

[0101] The first Y-axis sliding pair has its guide rail mounted to plate 40 by fasteners, and its slider mounted to the first wedge unit 54 by fasteners, as shown below. Figure 10 As shown.

[0102] An inclined sliding pair has its guide rail mounted to the upper wedge block of the first wedge unit 54 by fasteners, and its slider mounted to the lower wedge block of the first wedge unit 54 by fasteners, as shown below. Figure 13 As shown.

[0103] like Figures 12-13 As shown, the transmitted light focusing unit 6 includes:

[0104] Mounting base 60 is mounted on plate 70 by fasteners and is located in front of plate 71.

[0105] The housing of the second motor 61 is mounted on the second mounting base 60 by fasteners, and its output shaft is connected to the second ball screw.

[0106] The second ball screw is rotatably mounted on the second mounting base 60 via a bearing, and its second nut 62 is connected to the second connecting bracket 63; in this embodiment, the second connecting bracket 63 is embedded in the second nut 62, as shown below. Figure 13 As shown.

[0107] A pair of second-order wedge units 64, each with its lower wedge block connected to the same lower sliding plate 67, form a first Y-axis sliding pair with the first plate 70. The outer surface of the lower wedge block of one of the second-order wedge units 64 is connected to the second connecting frame 63. In this embodiment, the lower sliding plate 67 is connected to the upper wedge block of the second-order wedge unit 64 via connectors and fasteners, such as... Figure 13 As shown.

[0108] The rear end faces of the upper wedge blocks of a pair of second wedge units 64 are connected to the front surface of the same second slide plate 65; an inclined sliding pair is formed between the upper and lower wedge blocks of the second wedge unit 64.

[0109] The second skateboard 65 and the second board 71 are slidably connected;

[0110] The mounting plate 66 is connected to the upper wedge block of a pair of second wedge units 64 and is located above the lower slide plate 67, on which a transmission light source 3 is provided.

[0111] like Figures 15-17 As shown, the stage 1 includes:

[0112] Base 10 is connected to slide 55 (number one) by fasteners;

[0113] The fixed rail 11, the lower guide rail 12 and the upper guide rail 13 are slidably connected from bottom to top, and the fixed rail 11 is fixedly connected to the base 10 by fasteners.

[0114] The lower guide rail 12 is connected to the output end of the Y-axis module via the Y-axis connector 8; the upper guide rail 13 is connected to the output end of the X-axis module via the X-axis connector 9.

[0115] Both the Y-axis module and the X-axis module are located on the base 10.

[0116] like Figure 17 As shown, the lower guide rail 12 and the upper guide rail 13 are slidably connected by the inner slide rail 14 and the outer slide rail 15;

[0117] The inner slide rail 14 is located on the lower guide rail 12, and the outer slide rail 15 is located on the upper guide rail 13.

[0118] Similarly, the lower guide rail 12 and the fixed rail 11 are also slidably connected through the inner slide rail and the outer slide rail.

[0119] In this embodiment, the Y-axis module and the X-axis module have the same structure, including: a motor and a ball screw connected to the motor.

[0120] Locking parts ( Figure 4 The red component (connected to platform 1) is only for installation and use during shipment and fixing. Figure 15 Not displayed.

[0121] Working principle of the independent automatic object focal length and transmitted light focal length adjustment structure for infrared double-sided overlay:

[0122] Stage 1 carries the wafer, and imaging optical path unit 2 (camera and objective lens switching mechanism) is used to take pictures and images. The objective lens switching mechanism can switch between different magnification objective lenses to achieve different measurement accuracy requirements.

[0123] The upper and lower structure of stage 1 can ensure that the wafer is on the imaging focal plane required by the camera;

[0124] The light source adopts bottom transmission illumination. Because the measurement requires the camera to take product pattern MARKs on the top and bottom sides of the wafer, and the products will have different thicknesses, the focal plane of the projection light source is required to meet the different focal plane changes. Therefore, the transmission light is designed to be able to automatically adjust up and down without affecting the independent movement of the stage 1.

[0125] The wafer has already been patterned using a photomask, and there are markings on the wafer indicating the pattern. By detecting the coordinate positions of the upper and lower markings, the lithography machine is informed whether the pattern has been misaligned. This measurement system is used to detect the offset distance between the upper and lower lithography layers and is not used for the actual lithography process.

[0126] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the present invention. Any equivalent substitutions or modifications made by those skilled in the art to the technical solutions and content disclosed in the present invention without departing from the scope of the present invention shall be deemed to have remained within the protection scope of the present invention.

Claims

1. A structure for adjusting the focal length of an independently measured object and the focal length of transmitted light using infrared double-sided overlay, characterized in that, include: The stage (1) is used to support the wafer. It is a hollow structure and is connected to the output end of the stage focusing unit (5). The stage focusing unit (5) is movable along the base (4) and in the Z direction; Imaging optical path unit (2) is disposed above stage (1); And a transmission light source (3) is set below the hollow area of ​​the stage (1), and is connected to the output end of the transmission light focusing unit (6); The transmitted light focusing unit (6) is movable along the base plate (7) and in the Z direction, and the base plate (7) is connected to the base (4); The base (4) includes: Plate 1 (40), and Plate 2 (41) connected to Plate 1 (40); Plate 2 (41) extends upward from Plate 1 (40) along the Z direction; The base plate (7) includes: a first plate (70) and a second plate (71) connected to the first plate (70); the second plate (71) extends upward from the first plate (70) along the Z direction; The stage focusing unit (5) forms a Z-axis sliding pair with the front surface of the second plate (41); The transmitted light focusing unit (6) is located in the area enclosed by the stage focusing unit (5), and forms a second Z-axis sliding pair with the second plate (71).

2. The infrared double-sided overlay independent automatic object focal length and transmitted light focal length adjustment structure according to claim 1, characterized in that, The first Z-axis sliding pair includes: Guide rail and slider that mates with the guide rail; The guide rail is set on plate two (41), and the slider is set on the stage focusing unit (5).

3. The infrared double-sided overlay independent automatic object focal length and transmitted light focal length adjustment structure according to claim 1, characterized in that, The second Z-axis sliding pair includes: Slide rail one, which is set on plate number one (70), has a dovetail groove on its outer surface along the X direction; The second slide rail, which is matched with the dovetail groove, is located in the transmission light focusing unit (6).

4. The infrared double-sided overlay independent automatic object focal length and transmitted light focal length adjustment structure according to claim 1, characterized in that, The stage focusing unit (5) includes: Mounting base 1 (50) is located on plate 1 (40) and behind plate 2 (71), with its front end passing through plate 2 (41) and plate 1 (55) in sequence. Motor No. 1 (51) has its housing set on Mount No. 1 (50), and its output shaft is connected to Ball Screw No. 1; The first ball screw is rotatably mounted on the first mounting base (50), and its first nut (52) is connected to the first connecting bracket (53); The first connecting frame (53) includes two free ends distributed along the X direction, and windows for the first connecting frame (53) to pass through are opened on the second plate (41) and the first sliding plate (55); And the first wedge unit (54), the inner surface of its lower wedge block is connected to one free end of the first connecting frame (53), the rear end face of its upper wedge block is connected to the front surface of the same first slide plate (55), and a first Y-direction sliding pair is formed between its lower wedge block and plate one (40); The first sliding plate (55) and the second sliding plate (41) form the first Z-axis sliding pair; An inclined sliding pair is formed between the upper and lower wedge blocks of the first wedge unit (54).

5. The infrared double-sided overlay independent automatic object focal length and transmitted light focal length adjustment structure according to claim 4, characterized in that, The structure of the first Y-axis sliding pair and the inclined sliding pair is the same as that of the first Z-axis sliding pair.

6. The infrared double-sided overlay independent automatic object focal length and transmitted light focal length adjustment structure according to claim 1, characterized in that, The transmitted light focusing unit (6) includes: Mounting base 2 (60) is located on plate 1 (70) and in front of plate 2 (71); The second motor (61) has its housing mounted on the second mounting base (60), and its output shaft is connected to the second ball screw; The second ball screw is rotatably mounted on the second mounting base (60), and its second nut (62) is connected to the second connecting bracket (63); A pair of second wedge units (64) have their lower wedge blocks connected to the same lower slide plate (67). The lower slide plate (67) and the first plate (70) form a first Y-axis sliding pair. The outer surface of the lower wedge block of one of the second wedge units (64) is connected to the second connecting frame (63). The rear end faces of the upper wedge blocks of the pair of second wedge units (64) are connected to the front surface of the same second slide plate (65); an inclined sliding pair is formed between the upper and lower wedge blocks of the second wedge unit (64); The second sliding plate (65) and the second plate (71) form the second Z-axis sliding pair; The mounting plate (66) is connected to the upper wedge block of a pair of second wedge units (64) and is located above the lower slide plate (67), on which the transmitted light source (3) is provided.

7. The infrared double-sided overlay independent automatic object focal length and transmitted light focal length adjustment structure according to claim 1, characterized in that, The stage (1) includes: The base (10) is connected to the output end of the stage focusing unit (5); The fixed rail (11), the lower guide rail (12) and the upper guide rail (13) are slidably connected from bottom to top, and the fixed rail (11) is fixedly connected to the base (10); The lower guide rail (12) is connected to the output end of the Y-axis module via the Y-axis connector (8); The upper guide rail (13) is connected to the output end of the X-axis module via the X-axis connector (9); Both the Y-axis module and the X-axis module are mounted on the base (10).

8. The infrared double-sided overlay independent automatic object focal length and transmitted light focal length adjustment structure according to claim 7, characterized in that, The lower guide rail (12) and the upper guide rail (13) are slidably connected by an inner slide rail (14) and an outer slide rail (15); The inner slide rail (14) is disposed on the lower guide rail (12), and the outer slide rail (15) is disposed on the upper guide rail (13).

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