Exposure device

Abstract

The utility model provides an exposure device, which belongs to the field of photoetching and calibration and is characterized in that an exposure station of the exposure device comprises a movable carrying table, an exposure head, a plurality of calibration plates, an upper camera assembly and a lower camera assembly, the calibration plate is arranged at the periphery of the movable carrying table; the exposure head and the upper camera assembly are arranged above the movable carrying table, and the lower camera assembly is arranged below the movable carrying table and can controllably move in the plane and the Z direction. The calibration plate provided with the calibration mark part and the transparent exposure mark part is adopted to replace traditional BLED dotting alignment, the calibration precision is improved, meanwhile, correction is set, the method is particularly suitable for precise alignment of an inner layer, and application and popularization in the field of semiconductor detection or processing needing alignment such as PCBs and wafers are facilitated.

Description

Technical Field

[0001] This utility model belongs to the field of photolithography and calibration, and specifically relates to an exposure device. Background Technology

[0002] In the precision processing and testing of integrated circuits, alignment is one of the important processes. For example, wafers and PCBs are important carriers of various electronic components. Their testing and processing (exposure, photolithography, overlay, etc.) require increasingly higher precision, and this requirement extends from the outer layer to the inner layer, with precise alignment of the inner layer being necessary.

[0003] However, in existing inner layer solutions, the actual position of the BLED dots cannot be confirmed before each exposure, leading to errors between the calibrated and actual positions. This results in limited inner layer alignment accuracy, failing to achieve the desired outcome. Therefore, an improved inner layer alignment exposure solution is needed. Utility Model Content

[0004] In order to overcome the shortcomings of the prior art, the purpose of this utility model is to provide an exposure device that can solve the above-mentioned problems.

[0005] Design principle: To solve the problem of inner layer alignment accuracy, the BLED dot marking method is eliminated. First, the front is exposed to mark the pattern, and then the board is flipped and the mark position is photographed from the back. The upper camera photographs the mark point of the corresponding calibration board, and the lower camera photographs the corresponding calibrated mark point and the exposed mark point. The true position coordinates of the exposed mark are obtained through the correspondence between the two. The back pattern is exposed according to the true position coordinates to improve the inner layer accuracy.

[0006] An exposure device includes a loading station, an exposure station, a flipping module, and an unloading station. The exposure station includes a moving platform, an exposure head, multiple calibration plates, an upper camera assembly, and a lower camera assembly. The multiple calibration plates are disposed on the outer periphery of the moving platform. The exposure head and the upper camera assembly are disposed above the moving platform, and the multiple lower camera assemblies are disposed below the moving platform and can be controllably moved in the plane and Z-axis.

[0007] Furthermore, the moving platform is rectangular, and multiple calibration plates are set on the two sides of the moving platform. One of the two sets of lower camera assemblies is mounted on the X-axis camera moving axis group and moves along the X side of the moving platform. The other set of the two sets of lower camera assemblies is mounted on the Y-axis camera moving axis group and moves along the Y side of the moving platform.

[0008] Furthermore, the movable platform is a circular platform, and multiple calibration plates are set on one semi-circular side of the movable platform. The lower camera assembly is mounted on a ring camera movable axis group and moves along the lower outer periphery of the circular platform.

[0009] Further, make a notch or hollow treatment at the installation of the mobile platform calibration board, so that the field of view of the lower camera assembly can cover the whole calibration board.

[0010] Further, the calibration board comprises a left calibration mark part and a right transparent exposure mark part, the calibration mark part comprises a first blank buffer area, a calibration combined mark area and a second blank buffer area, the transparent exposure mark part comprises a board edge area, an exposure mark reserved area and a third blank buffer area; a first combined pattern is processed in the calibration combined mark area as a calibration combined mark, and a second combined pattern is arranged in the exposure mark reserved area as an exposure mark, and the second combined pattern is different from the first combined pattern.

[0011] Compared with the prior art, the application has the beneficial effects that: the calibration board provided with the calibration mark part and the transparent exposure mark part is used to replace the traditional BLED dotting alignment, the calibration precision is improved, and the correction is set, and the application is especially suitable for the accurate alignment of the inner layer, and is convenient for popularization and application in the semiconductor detection or processing field requiring alignment (such as overlay). BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 Fig. 2 is a top view of the exposure station structure of the exposure device;

[0013] Figure 2 Fig. 3 is a layout schematic diagram of the mobile platform, the calibration board, the upper camera assembly and the lower camera assembly of the exposure station;

[0014] Figure 3 Fig. 4 is a schematic diagram of different embodiments of the calibration board; Figure 4

[0015] Figure 5 Fig. 5 is a corresponding diagram of the exposure mark before and after turning over in the calibration method;

[0016] Figure 6 Fig. 6 is a position schematic diagram of the exposure ring in the correction method.

[0017] In the drawings,

[0018] 1, mobile platform;

[0019] 2, calibration board; 21, first combined pattern; 22, second combined pattern;

[0020] 3, upper camera assembly;

[0021] 4, lower camera assembly;

[0022] 5, X-direction camera moving shaft group;

[0023] 6, Y-direction camera moving shaft group.​ DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0025] Exposure apparatus

[0026] An exposure device, not shown, comprises a feeding station, an exposure station, a turnover module and a discharging station.

[0027] The exposure station comprises a moving platform 1, an exposure head, a plurality of calibration plates 2, an upper camera assembly 3 and a lower camera assembly 4.

[0028] Arrangement: a plurality of the calibration plates 2 are arranged at the outer periphery of the moving platform 1; the exposure head and the upper camera assembly 3 are arranged above the moving platform 1; a plurality of the lower camera assemblies 4 are arranged below the moving platform 1 and can be controlled to move in the plane and in the Z direction.

[0029] The feeding station and the discharging station provide feeding and discharging, which can be two functions of one station or can be two stations respectively performing the feeding or discharging function. The turnover module can be arranged outside the exposure station or integrated in the exposure station, for turning over a wafer or a PCB board and the like after one side is exposed, so that the other side faces upward.

[0030] In one example, referring to Figures 1-2 , the moving platform 1 is rectangular, a plurality of the calibration plates 2 are arranged at the two side edges of the moving platform 1, one of the two groups of the lower camera assemblies 4 is mounted on the X-direction camera moving shaft group 5 and moves along the X-side below the moving platform 1, and the other of the two groups of the lower camera assemblies 4 is mounted on the Y-direction camera moving shaft group 6 and moves along the Y-side below the moving platform 1.

[0031] In another example, not shown, the moving platform 1 is a circular platform, a plurality of the calibration plates 2 are arranged at one semicircular side edge of the moving platform 1, and the lower camera assembly 4 is mounted on a ring-shaped camera moving shaft group and moves along the outer periphery below the circular platform. This example is more suitable for the exposure scene of a circular board (such as a wafer).

[0032] Further, a notch or a hollow treatment is made at the position where the moving platform 1 is mounted with the calibration plate 2, so that the field of view of the lower camera assembly 4 can cover the entire calibration plate 2.

[0033] In a specific example, the mobile platform 1 is a gas suction positioning platform movable along the Y direction, the exposure head is an exposure head of ultraviolet and deep ultraviolet light source, and the upper camera assembly 3 and the lower camera assembly 4 include a camera, a lens and a ring light source. The X direction camera moving shaft group 5 and the Y direction camera moving shaft group 6 adopt one of a screw motor, a linear motor and a motor belt slider assembly, as long as the smooth driving of the camera assembly is achieved.

[0034] In a specific example, referring to Figure 3 and Figure 4 , the calibration plate 2 includes a left calibration mark part and a right transparent exposure mark part. The calibration mark part includes a first blank buffer zone, a calibration combined mark zone and a second blank buffer zone. The transparent exposure mark part includes a plate edge zone, an exposure mark reserved zone and a third blank buffer zone. The first combined pattern 21 is processed in the calibration combined mark zone as a calibration combined mark. The second combined pattern 22 is provided in the exposure mark reserved zone as an exposure mark. The second combined pattern is different from the first combined pattern.

[0035] In a specific example, the length dimensions of the first blank buffer zone, the second blank buffer zone and the third blank buffer zone along the long side of the calibration plate are equal, and each is a size a. The length dimensions of the calibration combined mark zone, the plate edge zone and the exposure mark reserved zone along the long side of the calibration plate are equal, and each is a size b.

[0036] Calibration method

[0037] A calibration method for the exposure device is provided. The calibration method includes the following steps.

[0038] S1, three exposure marks are exposed on the adjacent two sides of the front surface of the plate. The upper camera assembly 3 records the position information of the exposure marks on the plate.

[0039] In a specific example, referring to Figure 5 , the three exposure marks are exposure mark-1, exposure mark-2 and exposure mark-3. At this time, the relative position relationship between the exposure marks and the exposure images during front surface exposure can be determined with the exposure mark image and the position information of the front surface of the plate.

[0040] S2, the plate is turned over, the lower camera assembly 4 collects the position information of the three exposure marks on the plate and the position information corresponding to the calibration plate 2, and at the same time, the upper camera assembly 3 collects the calibration mark part of the same calibration plate 2.

[0041] S3, position calibration, the position relationship between the upper and lower cameras is determined by the two position information of the same calibration plate, and the exposure mark photographed by the lower camera assembly 4 is converted to the coordinate system of the upper camera through the position relationship between the upper and lower cameras, so as to determine the alignment deviation before and after the plate is turned over, and complete the position calibration.

[0042] Correction method

[0043] For the foregoing calibration method, it further includes a correction step, after a specified number of plate calibration and processing, the calibration of the exposure device is corrected, and the correction method includes.

[0044] S4, repeat step S1, make a correction exposure mark on the plate to be exposed, and calculate the image position information required when the back surface is exposed.

[0045] S5, exposure ring exposure, re-expose an exposure ring at the exposure mark position after the plate is turned over to make a positioning ring, and the exposure ring is sleeved on the outer periphery of the exposure mark. See Figure 6 The figure shows that the exposure ring is exposed on the outer periphery of a mark circle, and corresponding exposure rings can also be exposed on three or two mark circles.

[0046] S6, error determination, the exposure mark position information and the exposure ring position information collected by the upper camera assembly 3 and the lower camera assembly 4 are used to determine the deviation between the center of the exposure mark and the center of the corresponding exposure ring as the accuracy error of the alignment, and the correction is completed.

[0047] Through the above device and method, the exposure accuracy can be improved to within 10um, especially suitable for multi-layer exposure.

[0048] Compared with the traditional exposure device, the differentiated improvement contents are as follows.

[0049] 1. The position calibration of the upper and lower cameras can be performed through the calibration mark on the calibration glass every time the exposure is performed, and the positioning coordinate system of the lower camera is converted to the positioning coordinate system of the upper camera (dynamic calibration, which is equivalent to calibration compensation of the coordinate system of the lower camera and the upper camera every time).

[0050] 2. The interlayer exposure accuracy is improved by about one time of the original BLED dotting method.

[0051] 3. The problems of unclear MARK point imaging of BLED dotting, and exposure point position deviation caused by the fact that the flatness of the BLED assembly and the flatness of the exposure table are not coplanar are solved.

[0052] It should be finally pointed out that: the above examples are only used to illustrate the technical solutions of the utility model, and not to limit them; although the utility model has been explained in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement to part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the utility model.

Claims

1. An exposure apparatus, comprising a loading station, an exposure station, a flipping module, and an unloading station, characterized in that: The exposure station includes a mobile stage (1), an exposure head, multiple calibration plates (2), an upper camera assembly (3), and a lower camera assembly (4); Multiple calibration plates (2) are disposed on the outer periphery of the movable stage (1); an exposure head and an upper camera assembly (3) are disposed above the movable stage (1); multiple lower camera assemblies (4) are disposed below the movable stage (1) and can be moved controllably in the plane and Z direction.

2. The exposure apparatus according to claim 1, characterized in that: The mobile stage (1) is rectangular, and multiple calibration plates (2) are set on the two sides of the mobile stage (1). One of the two sets of lower camera assemblies (4) is installed on the X-axis camera moving axis assembly (5) and moves along the X side of the mobile stage (1) below. The other set of the two sets of lower camera assemblies (4) is installed on the Y-axis camera moving axis assembly (6) and moves along the Y side of the mobile stage (1) below.

3. The exposure apparatus according to claim 1, characterized in that: The movable platform (1) is a circular platform. Multiple calibration plates (2) are set on one semi-circular side of the movable platform (1). The lower camera assembly (4) is mounted on a ring camera moving axis group and moves along the lower periphery of the circular platform.

4. The exposure apparatus according to claim 2 or 3, characterized in that: Make a notch or cutout at the calibration plate (2) on the mobile stage (1) so that the field of view of the lower camera assembly (4) can cover the entire calibration plate (2).

5. The exposure apparatus according to claim 1, characterized in that: The calibration plate (2) includes a calibration mark section on the left and a transparent exposure mark section on the right. The calibration mark section includes a first blank buffer, a calibration combination mark area and a second blank buffer. The transparent exposure mark section includes a plate edge area, an exposure mark reserved area and a third blank buffer. A first combination pattern (21) is processed in the calibration combination mark area as a calibration combination mark. A second combination pattern (22) is provided in the exposure mark reserved area as an exposure mark. The second combination pattern is different from the first combination pattern.

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