Pixel repairing method and mask adjusting method used for same

Abstract

The invention belongs to the technical field of semiconductors, and discloses a pixel repairing method and a mask adjusting method used for the method.The pixel repairing method comprises the steps that an optical detection device is used for detecting the defect position where pixels fall off on a color film, and a color film array pattern on a substrate is provided with reference pixels; according to the relative position relation between the non-falling pixel adjacent to the defect position and the reference pixel, the defect coordinate position, corresponding to the defect position, on the color film array graph is calculated; configuring a mask plate with a pattern opening, and adjusting the position of the pattern opening based on the deviation between the defect coordinate position and the theoretical position of the pattern opening; and carrying out pixel repair on the color film under the pattern opening position by utilizing a photoetching process. According to the invention, the falling coordinate position of the color film pixel can be detected and positioned in time, and the falling pixel can be repaired in time through a photoetching process.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of semiconductor, and particularly relates to a pixel repair method and a mask adjustment method for the same. BACKGROUND

[0002] The color film on the Micro-OLED color film substrate is usually composed of three color sub-pixels R, G and B. In order to prevent color crosstalk between pixels, the three sub-pixels are usually made on the substrate respectively, and after the array of each sub-pixel is completed in turn, the sub-pixels are stacked to form a color film consistent with the entire color film array pattern.

[0003] Although the existing color film preparation method meets the requirements of high pixel density and small pixel size of Micro-OLED devices, there is a possibility of individual color film pixel falling off when preparing each layer of sub-pixel. However, the existing technology lacks the technology of timely and targeted positioning and repairing of color film pixel falling off, and cannot perform local wafer rework repair after negative photoresist exposure, thus causing the product to be scrapped and causing great yield loss. SUMMARY

[0004] The purpose of the present application is to provide a pixel repair method and a mask adjustment method for the same, to solve the technical problem of the prior art that it is difficult to timely and targetedly position and repair color film pixel falling off.

[0005] The pixel repair method comprises: detecting the defect position of pixel falling off on the color film by using an optical detection device, the color film array pattern on the substrate is provided with a reference pixel, and the defect coordinate position on the color film array pattern corresponding to the defect position is calculated through the relative position relationship between the non-falling-off pixel adjacent to the defect position and the reference pixel; configuring a mask plate having a pattern opening, and adjusting the position of the pattern opening based on the deviation between the defect coordinate position and the theoretical position of the pattern opening; performing pixel repair on the color film under the pattern opening position by using a photolithography process.

[0006] Preferably, the non-falling-off pixel adjacent to the defect position is determined at the same time as the relative position vector between the non-falling-off pixel and the defect position is determined as a first vector; the relative position vector between the non-falling-off pixel and the reference pixel is a second vector, and the defect coordinate position is calculated according to the first vector and the second vector.

[0007] Preferably, the mask plate is configured in a theoretical state on the substrate, and the position of the pattern opening on the color film array pattern is the theoretical position.

[0008] Preferably, the reference pixel is a reference coordinate point of the color filter array pattern, located at the corner of the color filter array pattern.

[0009] Preferably, the photolithography process includes recoating the corresponding sub-pixel at the defect location, exposure, and development.

[0010] Preferably, the graphic opening is a single-pixel graphic opening.

[0011] Preferably, the color filter is formed by stacking array pixels on a substrate in a flat manner using three types of color sub-pixels, and the color filter array pattern is the theoretical pattern of the color filter.

[0012] Preferably, the pixel repair method can be implemented after the array of pixels of any sub-pixel is tiled on the substrate, and the adjacent undetached pixels are located in any direction around the defect location.

[0013] Preferably, the optical inspection equipment is an AOI (Automated Optical Inspection) equipment.

[0014] The present invention also provides a mask adjustment method for pixel repair, comprising: obtaining the defect coordinate position of a pixel falling off the color filter; obtaining the theoretical position of the pattern opening of a single pixel on the mask; calculating the deviation between the defect coordinate position and the theoretical position; and adjusting the position of the pattern opening according to the deviation so that the pattern opening is aligned with the defect coordinate position.

[0015] The technical advantages of this invention are as follows: On the one hand, this invention can detect and locate the coordinate position of the color filter pixel detachment in a timely manner, and can set up a mask specifically for color filter pixel repair based on the coordinate position. On the other hand, it can make the pattern opening on the mask coincide with the corresponding color filter pixel detachment position, thereby making it possible to remake the corresponding sub-pixel at the detached color filter pixel, and ensuring the reliability of the sub-pixel remaking, thus solving the problem of not being able to detect and repair the color filter pixel in a timely manner after detachment. Attached Figure Description

[0016] Figure 1 This is a schematic flowchart of the pixel repair method of the present invention; Figure 2 This is a diagram showing the effect of completing the first layer of sub-pixels using the color filter preparation method of the present invention; Figure 3 The image shows the effect of completing the second layer of sub-pixels using the color filter preparation method of the present invention; Figure 4 The image shows the effect of completing the third layer sub-pixel preparation using the color filter preparation method of the present invention; Figure 5 A schematic diagram illustrating the principle of applying this invention after the third layer of sub-pixels has been prepared in the color filter preparation method; Figure 6This is a schematic diagram of the mask used in the pixel repair method of the present invention. Detailed Implementation

[0017] The following detailed description of the embodiments, with reference to the accompanying drawings, will further illustrate the specific implementation of the present invention, in order to help those skilled in the art to have a more complete, accurate, and in-depth understanding of the inventive concept and technical solution of the present invention.

[0018] In existing technologies, the color filter on a Micro-OLED color filter substrate is composed of three color sub-pixels: R (red), G (green), and B (blue). The color filter array pattern is a theoretical pattern of the color filter, which is adapted to the corresponding substrate before color filter fabrication, such as... Figure 3 As shown. To prevent color crosstalk between pixels, the three sub-pixels are usually fabricated separately on the substrate to form a pixel array. The three sub-pixels are fabricated on the substrate in the order of blue, green and red, respectively. These sub-pixels are stacked to form a color filter that is consistent with the pattern of the entire color filter array.

[0019] During fabrication, blue array pixels are first fabricated on the color filter substrate, such as... Figure 1 As shown; next, a green array of pixels is fabricated on the color filter substrate, as follows. Figure 2 As shown; finally, red array pixels are fabricated on the color filter substrate, as shown. Figure 3 As shown.

[0020] The difficulty of repairing and reworking detached pixels using existing technologies lies in how to align the photolithography equipment and mask used for repair with the detached pixel location on a newly fabricated substrate for targeted individual pixel repair. The core concept of this invention is to use a new single-pixel mask on the color filter substrate where pixel detachment has occurred. By calculating positioning and positional deviations, alignment is achieved, and the detached pixel is re-coated, exposed, and developed, thus re-fabricating it onto the substrate. This invention solves the problem of the inability to rework detached color filter pixels and effectively controls the positional accuracy and morphology of the repaired pixels through the exposure method.

[0021] This embodiment uses the example of pixel detachment discovered after fabricating red array pixels on a color filter substrate to illustrate the method, as detailed below.

[0022] like Figures 1-6 As shown, the present invention provides a pixel repair method, which includes the following steps.

[0023] S1. An optical inspection device is used to detect the location of pixel detachment defects on the color filter. A reference pixel is defined in the color filter array pattern on the substrate. The relative positional relationship between the adjacent non-detached pixels and the reference pixel is used to calculate the defect coordinates on the color filter array pattern corresponding to the defect location. The optical inspection device is an AOI (Automated Optical Inspection) device, which has good precision inspection capabilities.

[0024] Let Rp represent the pixel that has detached, which is a red sub-pixel. This step uses an optical inspection device to locate the defective position of the detached pixel. This is its relative position within the optical inspection device, and the pixel G1 to the left of pixel Rp is used as the neighboring undetached pixel for calculation. The optical inspection device measures the relative position (x1, y1) of the undetached pixel G1 within the device. Based on this position, the neighboring undetached pixels G1 can be determined, and simultaneously, the relative position vector between the undetached pixel G1 and the defective position can be determined, serving as the first vector.

[0025] The bottom left pixel B0 of the entire color filter array pattern is predefined as the reference pixel. The optical inspection device measures the relative position (x0, y0) of the reference pixel B0 within the device. This step can also be expressed as a second vector, (x1-x0, y1-y0), using the relative position vector between the undisturbed pixel G1 and the reference pixel B0.

[0026] The reference pixel is the reference coordinate point of the color filter array pattern. From the perspective of a two-dimensional coordinate system, the reference pixel is usually set in the lower left corner, but depending on the equipment or process requirements, the reference pixel can also be located at other corners of the color filter array pattern, such as the lower right corner, upper left corner, and upper right corner.

[0027] In fact, the relative position of each pixel to the reference pixel B0 is defined in the color filter array pattern in the design drawing. The reference pixel B0 is the origin of the coordinates of the color filter array pattern. Therefore, by mapping the second vector to the color filter array pattern, we can obtain the theoretical position (x2, y2) of the undone pixel G1 in the color filter array pattern.

[0028] Based on the first vector, the theoretical position (xp, yp) of the pixel Rp that detached to the right of the non-detached pixel G1 can be derived. This theoretical position is the defect coordinate position on the color filter array pattern.

[0029] S2. Configure a mask with a graphic opening, and adjust the position of the graphic opening based on the deviation between the defect coordinate position and the theoretical position of the graphic opening.

[0030] Because a new photomask is needed to specifically recoat, expose, and develop the detached pixels (Rp), i.e., to re-fabricate the detached individual pixels (Rp) onto the substrate using photolithography, a dedicated photomask is required for repair. This photomask is designed with patterned openings for repair. Since generally only one-to-one repair of a detached individual pixel is needed, the photomask can have only one patterned opening for a single pixel, and can have only one opening. However, if necessary, more than one patterned opening can be provided on the photomask, but usually, the position of the patterned opening can only be adjusted specifically based on the position of a particular opening to achieve adjustment of the patterned opening position during pixel repair.

[0031] like Figure 6 As shown, the mask in this embodiment has only one pattern opening. Based on the theoretical state (i.e., the state of the mask before position compensation), the theoretical position of the pattern opening is (xp0, yp0). If the pixel is to be repaired to the position of the pixel that has fallen off through the pattern opening on the mask, the deviation between the two needs to be made up before photolithography is performed by adjusting the position.

[0032] This invention also discloses a mask adjustment method, comprising: first, obtaining the defect coordinates (xp, yp) of a pixel detachment on the color filter through step S1; then, obtaining the theoretical position (xp0, yp0) of the pattern opening of a single pixel on the mask; calculating the deviation (xp-xp0, yp-yp0) between the defect coordinates and the theoretical position; and adjusting the position of the pattern opening according to the deviation to align the pattern opening with the defect coordinates. If the equipment performing the photolithography process is an exposure machine, the deviation (xp-xp0, yp-yp0) is input into the overlay parameter of the exposure machine for mask alignment compensation adjustment.

[0033] S3. Use photolithography to repair pixels in the color filter at the opening position of the pattern.

[0034] This step uses photolithography equipment to specifically recoat, expose, and develop the detached pixel Rp, thereby re-fabricating the red sub-pixel to the position of pixel Rp and completing the repair of the color filter pixel.

[0035] The pixel repair method can be implemented after the array of any sub-pixel is tiled on the substrate. The adjacent undetached pixels are located in any direction around the defect location, such as the right, top, bottom, upper left, lower left, upper right, or lower right side of the detached pixel.

[0036] To complete the fabrication of an array of sub-pixels, the detached pixel must have at least two adjacent, undetached pixels surrounding it. Therefore, this step is performed after the array of any sub-pixel is fabricated on the substrate. In application, first check whether pixel detachment has occurred on the color filter. If pixel detachment is found, the repair method provided by this invention can be applied. First, step S1 is executed.

[0037] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A pixel patching method, characterized by, The application comprises the following steps: detecting the defect position of pixel falling off on the color film by optical detection equipment, the color film array pattern on the substrate is provided with reference pixels, and the defect coordinate position on the color film array pattern is calculated by the relative position relationship between the non-falling-off pixels adjacent to the defect position and the reference pixels; configuring a mask plate with pattern openings, and adjusting the position of the pattern openings based on the deviation between the defect coordinate position and the theoretical position of the pattern openings; performing pixel repair on the color film under the pattern opening position by using photolithography process.

2. The pixel patching method of claim 1, wherein, The relative position vector between the non-falling-off pixels adjacent to the defect position and the defect position is determined as a first vector, and the relative position vector between the non-falling-off pixels and the reference pixels is determined as a second vector, and the defect coordinate position is calculated according to the first vector and the second vector.

3. The pixel patching method of claim 1, wherein, The mask plate is configured in the theoretical state on the substrate, and the position of the pattern openings on the color film array pattern is the theoretical position.

4. The pixel patching method of claim 1, wherein, The reference pixels are reference coordinate points of the color film array pattern, and are located at the corners of the color film array pattern.

5. The pixel patching method of claim 1, wherein, The photolithography process comprises re-gluing, exposing and developing corresponding sub-pixels on the defect position.

6. The pixel patching method of claim 1, wherein, The pattern openings are single-pixel pattern openings.

7. The pixel patching method of claim 1, wherein, The color film is formed by stacking array pixels of three-color sub-pixels in a tiled manner on the substrate, and the color film array pattern is the theoretical pattern of the color film.

8. The pixel patching method of claim 7, wherein, The application can be implemented after the tiled production of array pixels of any sub-pixel on the substrate, and the adjacent non-falling-off pixels are located in any direction around the defect position.

9. The pixel patching method of claim 1, wherein, The optical detection equipment is an AOI detection equipment.

10. A method for mask adjustment for pixel repair, the method comprising: receiving a design layout; determining a pixel repair area in the design layout; determining a pixel repair mask for the pixel repair area; and adjusting the pixel repair mask based on a design layout feature. The application comprises the following steps: obtaining the defect coordinate position of pixel falling off on the color film; obtaining the theoretical position of the single-pixel pattern openings on the mask plate; calculating the deviation between the defect coordinate position and the theoretical position; and adjusting the position of the pattern openings according to the deviation to align the pattern openings with the defect coordinate position.

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