TWI906871B - Color-dependent defective pixel mitigation method - Google Patents

Abstract

Embodiments of the present disclosure generally relate to micro-LED displays and methods of fabricating micro-LED displays. A deposition pattern of a pixel is determined, in which each pixel includes at least four sub-pixels, each sub-pixel including sub-pixel isolation structures defining a well. A defective sub-pixel is identified, the defective sub-pixel including at least one of a first sub-pixel comprising a first sub-pixel color, a second sub-pixel comprising a second sub-pixel color, or a third sub-pixel comprising a third sub-pixel color. An intracell spare repair (ISR) sub-pixel is identified. The deposition pattern is determined based on the ISR sub-pixel and the defective sub-pixel. A color conversion material is deposited in the ISR sub-pixel. The color conversion material is configured to emit at least one of the first sub-pixel color, the second sub-pixel color, or the third sub-pixel color.

Description

Color-based defect pixel mitigation method

The embodiments disclosed herein generally relate to micro LED displays and methods for manufacturing micro LED displays. Specifically, the embodiments described herein provide methods and apparatus for repairing micro LED displays.

Light-emitting diode (LED) panels use LED arrays, where individual LEDs provide individually controllable pixel elements. These LED panels are used in computers, touchpad devices, personal digital assistants (PDAs), mobile phones, television screens, and more.

Light-emitting diode (LED) technology is widely used in display technology. Generally, LED technology is implemented using LED panels with LED arrays. Each LED within the array provides an individually controllable pixel element, allowing users to display customized images on the LED panel. Therefore, in one example, LED technology might be a display mechanism suitable for end-user display devices, including computer monitors, touchpad devices, personal digital assistants (PDAs), mobile phones, television screens, etc. Current LED technology has provided LED panel systems using micron-sized LEDs (also known as micro-LEDs) based on III-V semiconductor technology. Compared to organic light-emitting diodes (OLEDs), micro-LEDs offer several advantages, such as higher energy efficiency, stronger display brightness, and longer display lifespan. Compared to OLEDs, manufacturers can also produce micro-LEDs using fewer material layers in the display stack, which reduces the complexity and cost associated with LED production.

Another method that bypasses the pick-and-place step is to selectively deposit color-changing agents (such as quantum dots, nanostructures, photoluminescent materials, or organic materials) at specific pixel locations on a substrate made of monochromatic LEDs. Monochromatic LEDs can produce relatively short-wavelength light, such as violet or blue light, and the color-changing agent can convert this short-wavelength light into longer-wavelength light, such as red, blue, or green light, for use with red, blue, or green pixels. Selective deposition of the color-changing agent can be achieved using high-resolution shadow masks or controllable inkjet or aerosol printing.

However, the manufacture of micro-LED panels still faces challenges. Therefore, this field requires improved micro-LED displays and methods for manufacturing them.

In some embodiments, a method is provided. The method includes determining a deposition pattern of pixels, wherein each pixel comprises at least four sub-pixels, and each sub-pixel comprises a sub-pixel isolation structure defining a well. Defective sub-pixels are identified, comprising at least one of: a first sub-pixel including a first sub-pixel color, a second sub-pixel including a second sub-pixel color, or a third sub-pixel including a third sub-pixel color. Backup repair sub-pixels are identified within the unit. A deposition pattern is determined based on the ISR sub-pixels and the defective sub-pixels. Color-changing material is deposited in the ISR sub-pixels. The color-changing material is configured to emit at least one of the first sub-pixel color, the second sub-pixel color, or the third sub-pixel color.

In other embodiments, a method is provided. The method includes determining a deposition pattern of pixels, each pixel comprising at least four sub-pixels, each sub-pixel comprising a sub-pixel isolation structure defining a well. Based on a first sub-pixel chromaticity threshold, a first sub-pixel including a first sub-pixel color is prioritized over a second sub-pixel including a second sub-pixel color and a third sub-pixel including a third sub-pixel color. Based on a second sub-pixel chromaticity threshold, a second sub-pixel including a second sub-pixel color is prioritized over a third sub-pixel including a third sub-pixel color. Based on a third sub-pixel chromaticity threshold, a third sub-pixel including a third sub-pixel color is prioritized over a fourth sub-pixel that does not have a sub-pixel color. A pixel is formed based on the first sub-pixel chromaticity threshold, the second sub-pixel chromaticity threshold, and the third sub-pixel chromaticity threshold. Color conversion material configured to emit a first sub-pixel color, a second sub-pixel color, a third sub-pixel color, or no sub-pixel color is deposited in each well according to the deposition pattern.

In other embodiments, a method is provided. The method includes determining a deposition pattern of pixels, wherein each pixel includes at least four sub-pixels, and each sub-pixel includes a sub-pixel isolation structure defining a well. A defective microLED is identified, the defective microLED including at least one of: a first microLED including a first sub-pixel color disposed thereon, a second microLED including a second sub-pixel color disposed thereon, or a third microLED including a third sub-pixel color disposed thereon. A backup repair (ISR) microLED within a unit is identified. A deposition pattern is determined based on the ISR microLED and the defective microLED. A color-changing material is deposited over the ISR microLED. The color-changing material is configured to emit at least one of the first sub-pixel color, the second sub-pixel color, or the third sub-pixel color.

This patent or application contains at least one color drawing. Upon request and payment of the necessary fees, the office will provide a copy of the published color drawing of this patent or application. Thus, the methods for understanding the above-described features of this disclosure can be understood in detail. A more detailed description of this disclosure, briefly summarized above, can be seen with reference to the embodiments, some of which are depicted in the accompanying drawings. However, it should be noted that the accompanying drawings only show exemplary embodiments and should not be considered as limiting its scope, and other equivalent embodiments are permissible.

100A: pixels

100B: pixels

101: Pixel Array

102: Backplate

103: Adhesive Materials

104: Subpixel Isolation (SI) Structure

105: Trap

106: Miniature LED

108: Electrode

109: Subpixel

110: First subpixel

112: Second subpixel

114: Third subpixel

115: Color Conversion Materials

115a: Color Conversion Material

115b: Color conversion material

115c: Color conversion material

115d: Color Conversion Material

116: Fourth sub-pixel

117: Sacrificial Materials

122: First defective subpixel

124: Second defective subpixel

130: Subpixel

136: Subpixel

140: Subpixel

142: Subpixel

144: Subpixel

150: Miniature LED Display

152: dividing line

200: Pixel Array

210: pixels

220 pixels

230 pixels

240 pixels

250: Pixel Array

300 pixels

350 pixels

400: Pixel Array

410: pixels

420 pixels

430 pixels

440 pixels

450: Pixel Array

Figure 1A is a cross-sectional view of a pixel prior to the method of manufacturing a microLED display according to an embodiment.

Figure 1B is a top view of the pixels prior to a method for manufacturing a microLED display according to some embodiments described herein.

Figure 1C is a cross-sectional view of a pixel according to the embodiment described herein.

Figure 1D is a top view of a microLED display prior to a method for manufacturing a microLED display according to some embodiments described herein.

Figure 2A is a top view of a portion of the pixel array prior to a method for manufacturing a micro-LED display according to the first embodiment described herein.

Figure 2B is a top view of a portion of the pixel array following a method for manufacturing a micro-LED display according to the first embodiment described herein.

Figure 3A is a top view of the pixels prior to the method of manufacturing a microLED display according to the second embodiment described herein.

Figure 3B is a top view of the pixels following the method for manufacturing a micro-LED display according to the second embodiment described herein.

Figure 4A is a top view of a portion of the pixel array prior to the method of manufacturing a micro-LED display according to the third embodiment described herein.

Figure 4B is a top view of a portion of the pixel array prior to the method of manufacturing a micro-LED display according to the third embodiment described herein.

For ease of understanding, the same component symbols have been used to represent common, identical components in the figures where possible. It is conceivable that the components and features of one embodiment can be beneficially incorporated into other embodiments without further description.

Brief Explanation Attached

To provide a detailed understanding of the methods featuring the above-described characteristics of this disclosure, a more specific description of the disclosure is briefly summarized above, with reference to the embodiments, some of which are depicted in the appendix. However, it should be noted that the appendix only illustrates typical embodiments of this disclosure and should not be construed as limiting its scope, as other equivalent embodiments are permissible.

This disclosure includes at least one page of color text. A copy of this document and its color text will be provided to the relevant authority upon request and payment of the necessary fees. Since the color text is submitted electronically via EFS-Web, only one set of text is required.

This disclosure generally relates to LED pixels and methods of manufacturing LED pixels. The apparatus typically includes two or more pixels disposed on a backplane, each pixel further including at least four subpixels. Each subpixel includes a microLED and a sub-pixel isolation (SI) structure. The backplane includes pairs of backplane electrodes disposed on the backplane. The microLED includes pairs of microLED electrodes coupled to the pairs of backplane electrodes. The backplane electrodes are disposed on the backplane. The SI structure is located on the upper surface between the microLEDs. The SI structure defines a well 105 for the subpixel, in which a color-converting material 115 is disposed.

Figure 1A is a cross-sectional view of pixel 100A prior to the method of manufacturing the microLED display 150. Figure 1B is a top view of pixel 100A, showing the dividing line 152 used in Figure 1A. Pixel 100A includes microLEDs 106 coupled to a backplane 102. MicroLEDs 106 are coupled to the backplane 102 via electrodes 108. Adhesive material 103 is disposed above the backplane 102, between the electrodes 108, and between the microLEDs 106. Pixel 100A includes at least four sub-pixels 109, such as a first sub-pixel 110, a second sub-pixel 112, a third sub-pixel 114, and a fourth sub-pixel 116. The at least four sub-pixels 109 are defined by a sub-pixel isolation (SI) structure 104. The SI structure 104 defines a well 105 for the at least four sub-pixels 109. In this example, all four subpixels 109 (first subpixel 110, second subpixel 112, third subpixel 114, and fourth subpixel 116) can be configured to independently adjust their output intensity.

At least three of the four sub-pixels 109 have color-changing materials 115 disposed in wells 105 above their respective micro-LEDs. The first sub-pixel 110 includes a first color-changing material 115a corresponding to the color of the first sub-pixel disposed in the well 105 above the micro-LED 106. The second sub-pixel 112 includes a second color-changing material 115b corresponding to the color of the second sub-pixel disposed in the well 105 above the micro-LED 106. The third sub-pixel 114 includes a third color-changing material 115c corresponding to the color of the third sub-pixel disposed in the well 105 above the micro-LED 106. The color-changing materials 115 correspond to the first sub-pixel color, the second sub-pixel color, the third sub-pixel color, or other sub-pixel colors, wherein the first sub-pixel color, the second sub-pixel color, the third sub-pixel color, or other sub-pixel colors may be different from each other or the same. The fourth sub-pixel 116 includes sacrificial material 117 disposed in a well 105 above the micro-LED 106. In other embodiments, the well 105 of the fourth sub-pixel 116 does not include color-changing material disposed in the well 105 above the micro-LED 106. In still other embodiments, the fourth sub-pixel 116 may include a fourth color-changing material 115d disposed in the well 105 above the micro-LED 106, corresponding to a first sub-pixel color, a second sub-pixel color, a third sub-pixel color, or another sub-pixel color, configured to emit a first, second, third, or fourth color, which may be different from each other. The first sub-pixel color, the second sub-pixel color, the third sub-pixel color, or other sub-pixel colors may be configured to emit red, green, blue, or other colors.

Figure 1C is a cross-sectional view of pixel 100B prior to a method of manufacturing the micro-LED display 150. Pixel 100B includes micro-LEDs 106 coupled to a backplane 102. Micro-LEDs 106 are coupled to the backplane 102 via electrodes 108. Adhesive material 103 is disposed above the backplane 102, between the electrodes 108, and between the micro-LEDs 106. Pixel 100B includes at least four sub-pixels 109, such as a first sub-pixel 110, a second sub-pixel 112, a third sub-pixel 114, and a fourth sub-pixel 116. The at least four sub-pixels 109 are defined by a sub-pixel isolation (SI) structure 104. The SI structure 104 defines a well 105 for the at least four sub-pixels 109. In this example, all four subpixels 109 (first subpixel 110, second subpixel 112, third subpixel 114, and fourth subpixel 116) can be configured to independently adjust their output intensity.

At least three of the four sub-pixels 109 have color-changing materials 115 disposed in wells 105 above their respective micro-LEDs. The first sub-pixel 110 includes a first color-changing material 115a corresponding to a first sub-pixel color disposed in the well 105 above the micro-LED 106. The second sub-pixel 112 includes a second color-changing material 115b corresponding to a second sub-pixel color disposed in the well 105 above the micro-LED 106. The third sub-pixel 114 includes a third color-changing material 115c corresponding to a third sub-pixel color disposed in the well 105 above the micro-LED 106. The color-changing materials 115 correspond to the first sub-pixel color, the second sub-pixel color, the third sub-pixel color, or other sub-pixel colors, wherein each of the first sub-pixel color, the second sub-pixel color, the third sub-pixel color, or other sub-pixel colors may be different from each other. In this exemplary embodiment, the fourth sub-pixel 116 may have a second color-changing material corresponding to the color of the second sub-pixel. This second color-changing material is the same as the second color-changing material deposited in the well 105 above the microLED 106 of the second sub-pixel 112, which is also deposited in the well 105 above the microLED 106 of the fourth sub-pixel 116. In other embodiments, the well 105 of the fourth sub-pixel 116 does not include the color-changing material disposed in the well 105 above the microLED 106. In still other embodiments, the fourth sub-pixel 116 may include a fourth color-changing material 115d disposed in the well 105 above the microLED 106, corresponding to the first sub-pixel color, the second sub-pixel color, the third sub-pixel color, or another sub-pixel color, configured to emit the first, second, third, or fourth color, which may be different from each other. The first sub-pixel color, the second sub-pixel color, the third sub-pixel color, or other sub-pixel colors can be red, green, blue, or white, and these colors can be different from or the same as each other. In this example, all four sub-pixels 109 (first sub-pixel 110, second sub-pixel 112, third sub-pixel 114, and fourth sub-pixel 116) can be configured to independently adjust their output intensity.

Figure 1D is a top view of a microLED display 150 prior to a method of manufacturing the microLED display 150. The microLED display includes a pixel array 101 of two or more pixels 100A. Pixel 100A includes microLEDs 106 coupled to a backplane 102. MicroLEDs 106 are coupled to the backplane 102 via electrodes 108. Adhesive material 103 is disposed above the backplane 102, between the electrodes 108, between the microLEDs 106, and in a subpixel isolation (SI) structure 104. SI structure 104 defines a well 105 for at least four subpixels 109. Pixel 100A includes at least four subpixels 109, such as a first subpixel 110, a second subpixel 112, a third subpixel 114, and a fourth subpixel 116. In this example, all four subpixels 109 (first subpixel 110, second subpixel 112, third subpixel 114, and fourth subpixel 116) of two or more pixels 100A can be configured to independently adjust their output intensity.

method

In some embodiments, the method of this disclosure can be understood with reference to Figures 2A and 2B. Figure 2A is a top view of a portion of a pixel array 200 prior to the method of manufacturing a micro LED display, showing an exemplary pixel array 200 of four pixels (pixels 210, 220, 230, and 240) arranged in a 2x2 pixel configuration, wherein each of the four pixels (pixels 210, 220, 230, and 240) has four sub-pixels 109 (a first sub-pixel 110, a second sub-pixel 112, a third sub-pixel 114, and a fourth sub-pixel 116) arranged in a 2x2 sub-pixel configuration. In this example, each of the four pixels (pixels 210, 220, 230, and 240) includes a micro LED 106 coupled to a backplane 102. Micro-LEDs 106 are coupled to a backplane 102 via electrodes 108. An adhesive material 103 is disposed above the backplane 102, between the electrodes 108, between the micro-LEDs 106, and in a sub-pixel isolation (SI) structure 104. The SI structure 104 defines a well 105 for at least four sub-pixels 109, such as a first sub-pixel 110, a second sub-pixel 112, a third sub-pixel 114, and a fourth sub-pixel 116. In this example, all four sub-pixels 109 (first sub-pixel 110, second sub-pixel 112, third sub-pixel 114, and fourth sub-pixel 116) of the four pixels (pixels 210, 220, 230, and 240) can be configured to independently adjust their output intensity.

Four pixels (pixels 210, 220, 230, and 240) of pixel array 200 share the same initial planned configuration, as shown in Figure 2A. The first sub-pixel 110 is configured to emit red, the second sub-pixel 112 is configured to emit green, the third sub-pixel 114 is configured to emit blue, and the fourth sub-pixel 116 is not configured to emit any color. If the first sub-pixel 110, the second sub-pixel 112, or the third sub-pixel 114 is defective, the fourth sub-pixel 116 can be a usable spare sub-pixel for intracell spare repair (ISR). In pixel array 200, one pixel (pixel 240) has two defective sub-pixels, where the first defective sub-pixel 122 of the four sub-pixels 109 is configured to emit green, and the second defective sub-pixel 124 is configured to emit blue. Defective subpixels can be identified by comparing them to subpixel color thresholds (e.g., green subpixel color threshold, blue subpixel color yield threshold, and/or red subpixel color threshold). In some embodiments, the subpixel color threshold may include a percentage value relative to the expected brightness value (e.g., lumens) of the subpixel. For example, the subpixel color threshold may include approximately 50% to approximately 100% of the expected brightness value (e.g., lumens of the subpixel color). For example, the subpixel color threshold may include a value approximately 50% of the expected brightness value of the subpixel.

Figure 2B is a top view of a portion of the pixel array 250 following the method of manufacturing a micro-LED display, showing the pixel array 200 after the step of repairing two defective sub-pixels (first defective sub-pixel 122 and second defective sub-pixel 124).

Defective subpixels are identified as having both green and blue subpixels. In this case, the green luminance value in the region of pixel array 200 is compared with the chromaticity threshold of the green subpixel, as described above. Additionally, as described above, the blue production in the region of pixel array 200 is compared with the chromaticity threshold of the blue subpixel. If the green production in the region of pixel array 200 is equal to or exceeds the chromaticity threshold of the green subpixel (e.g., approximately 50% to approximately 100%), and the blue production in the region of pixel array 200 is less than the chromaticity threshold of the blue subpixel (e.g., approximately 50% to approximately 100%), then the fourth subpixel 116 of pixel 240, which was initially not configured as an emission color, can be repurposed for ISR and configured to emit blue.

However, if the green output in the region of pixel array 200 is lower than the chromaticity threshold of the green subpixel, and the blue output in the region of pixel array 200 is lower than the chromaticity threshold of the blue subpixel, then the fourth subpixel 116 of pixel 240, which was not initially configured as an emission color, can be repurposed for the ISR and configured to emit green and/or blue. In some embodiments, green can be prioritized because the visual appearance of the pixel is improved by setting additional green in the ISR.

In some embodiments, it can be evaluated whether there is a fourth sub-pixel 116 that has not yet been used for ISR in adjacent, diagonal, or orthogonal (e.g., neighboring) pixels (e.g., pixels 210, 220, and 230) of pixel 240 in pixel array 200. If a fourth sub-pixel 116 is found, neighboring-cell spare repair (NSR) can occur, and the fourth sub-pixels of pixels 210, 220, and 230 can be configured to emit the remaining color (ISR) not set in the fourth sub-pixel 116 of pixel 240. For example, the NSR can be configured to emit blue.

If the fourth subpixel 116 is not suitable for NSR configuration to emit blue, the blue yield in the region of pixel array 200 can be compared with the chromaticity threshold of the blue subpixel. If the blue yield in the region of pixel array 200 is equal to or exceeds the chromaticity threshold of the blue subpixel, for example, about 50% to about 100%, the second defective subpixel 124 of pixel 240 may not be repairable. If the blue yield in the region of pixel array 200 is lower than the chromaticity threshold of the blue subpixel, the second defective subpixel 124 of pixel 240 can be physically repaired.

In some embodiments, the method of this disclosure can be understood with reference to Figures 3A and 3B. Figure 3A is a top view of the pixel array prior to the method of manufacturing a micro-LED display. Example pixel 300 includes micro-LEDs 106 coupled to a backplane 102. Micro-LEDs 106 are coupled to the backplane 102 via electrodes 108. Adhesive material 103 is disposed above the backplane 102, between the electrodes 108, between the micro-LEDs 106, and in a sub-pixel isolation (SI) structure 104. SI structure 104 defines a well 105 for at least four sub-pixels 109. Pixel 300 includes at least four sub-pixels 109, such as a first sub-pixel 110, a second sub-pixel 112, a third sub-pixel 114, and a fourth sub-pixel 116. In this example, all four subpixels 109 (first subpixel 110, second subpixel 112, third subpixel 114, and fourth subpixel 116) of two or more pixels 100A can be configured to independently adjust their output intensity. As shown in Figure 3A, all four subpixels 109 (first subpixel 110, second subpixel 112, third subpixel 114, and fourth subpixel 116) may not initially be configured to emit a color. Instead, the configuration of all four subpixels 109 (first subpixel 110, second subpixel 112, third subpixel 114, and fourth subpixel 116) may depend on how many of the four subpixels 109 are defective (e.g., due to brightness values below the subpixel color threshold and/or due to defective microLEDs), and the remaining operable subpixels are configured based on the priority assigned to colors. For example, two of the sub-pixels (first sub-pixel 110 and fourth sub-pixel 116) may be defective due to a defective microLED. In this example, all four sub-pixels 109 of pixel 300 (first sub-pixel 110, second sub-pixel 112, third sub-pixel 114, and fourth sub-pixel 116) can be configured to independently adjust their output intensity.

In some embodiments, one or more remaining operable subpixels may be configured to emit green to approach, reach, or exceed the chromaticity threshold of a red subpixel before configuring one or more remaining operable subpixels to emit red to approach, reach, or exceed the chromaticity threshold of a blue subpixel, or to emit blue to approach, reach, or exceed the chromaticity threshold of a blue subpixel. Without theoretical constraints, prioritizing green over blue and/or red can provide an enhanced visual appearance.

In some embodiments, one or more remaining operable subpixels may be configured to emit red to approach, reach, or exceed the chromaticity threshold of a green subpixel before configuring one or more remaining operable subpixels to emit green to approach, reach, or exceed the chromaticity threshold of a blue subpixel.

In some embodiments, one or more remaining operable subpixels may be configured to emit blue to approach, reach, or exceed the chromaticity threshold of a green subpixel before configuring one or more remaining operable subpixels to emit green to approach, reach, or exceed the chromaticity threshold of a red subpixel, or to emit red to approach, reach, or exceed the chromaticity threshold of a red subpixel.

Figure 3B is a top view of a portion of the manufactured pixel 350, showing pixel 300 after steps were taken to repair the two defective subpixels (subpixels 130 and 136). Although Figure 3B shows the subpixels filled with green and red, any color can be used to configure the subpixels. For example, blue can be used when the blue subpixel color threshold is not reached.

As shown in Figure 3B, due to defects in the microLEDs, two sub-pixels (sub-pixels 130 and 136) may be defective. Therefore, the second sub-pixel 112 or the third sub-pixel 114 of pixel 300 may be a usable backup sub-pixel for in-cell alternative repair (ISR), such as an ISR sub-pixel and/or a backup microLED for in-cell alternative repair (ISR), such as an ISR microLED. In some embodiments, one or more remaining operable sub-pixels may be configured to emit green to approach, reach, or exceed the chromaticity threshold of a red sub-pixel before configuring one or more remaining operable sub-pixels to emit red to approach, reach, or exceed the chromaticity threshold of a blue sub-pixel (wherein the chromaticity threshold of a green sub-pixel has not yet been reached or exceeded). The second sub-pixel 112 of pixel 350 was not initially configured to emit a color, but can be repurposed for the ISR and configured to emit green. Alternatively, the third sub-pixel 114 can also be used for the ISR (not shown).

In some embodiments, one or more remaining operable subpixels may be configured to emit red to approach, reach, or exceed the chromaticity threshold of the green subpixel before configuring one or more remaining operable subpixels to emit green to approach, reach, or exceed the chromaticity threshold of the blue subpixel (wherein the chromaticity threshold of the red subpixel has not yet been reached or exceeded). The third subpixel 114 of pixel 350 is not initially configured to emit a color, but can be repurposed for ISR and configured to emit red. Alternatively, the third subpixel 114 may also be used for ISR (not shown).

In some embodiments, the method of this disclosure can be understood with reference to Figures 4A and 4B. Figure 4A is a top view of a portion of a pixel array 400 prior to a method of manufacturing a micro LED display according to a first embodiment, showing an exemplary pixel array 400 of four pixels (pixels 410, 420, 430, and 440) arranged in a 2x2 pixel arrangement, wherein each of the four pixels (pixels 410, 420, 430, and 440) has four sub-pixels 109 (a first sub-pixel 110, a second sub-pixel 112, a third sub-pixel 114, and a fourth sub-pixel 116) arranged in a 2x2 sub-pixel arrangement. In this example, each of the four pixels (pixels 410, 420, 430, and 440) includes a micro LED 106 coupled to a backplane 102. Micro-LEDs 106 are coupled to a backplane 102 via electrodes 108. An adhesive material 103 is disposed above the backplane 102, between the electrodes 108, between the micro-LEDs 106, and in an SI structure 104. The SI structure 104 defines a well 105 for at least four sub-pixels 109, such as a first sub-pixel 110, a second sub-pixel 112, a third sub-pixel 114, and a fourth sub-pixel 116. In this example, all four sub-pixels 109 (first sub-pixel 110, second sub-pixel 112, third sub-pixel 114, and fourth sub-pixel 116) of the four pixels (pixels 410, 420, 430, and 440) can be configured to independently adjust their output intensity.

As shown in Figure 4A, the four pixels (pixels 410, 420, 430, and 440) of pixel array 400 share the same initial planned configuration. The first sub-pixel 110 will be configured to emit red, the second sub-pixel 112 will be configured to emit green, the third sub-pixel 114 will be configured to emit blue, and the fourth sub-pixel 116 will initially not be configured to emit any color. The initially unconfigured fourth sub-pixel 116 will, alternatively, serve as a usable backup sub-pixel for in-cell backup repair (ISR) if the first sub-pixel 110, the second sub-pixel 112, or the third sub-pixel 114 is defective due to not reaching or exceeding the sub-pixel color threshold and/or due to defects in the microLED. In pixel array 400, one of pixel 440 has four sub-pixels 109 (among which a first sub-pixel 110 will be configured to emit red, a second sub-pixel 112 will be configured to emit green, and a second sub-pixel 112 will be configured to emit blue), where the micro-LED 106 is defective, resulting in defects in sub-pixels 140, 142, and 144 of pixel 440.

Figure 4B is a top view of a portion of the pixel array 450 following the method of manufacturing a micro-LED display, showing the array 400 after repairing three defective sub-pixels (sub-pixels 140, 142, and 144). The fourth sub-pixel 116 of pixel 440, which has the three defective sub-pixels (sub-pixels 140, 142, and 144), was not initially configured to emit a color but is available for the ISR and configured to emit green. Regardless of theoretical constraints, configuring the ISR to emit green provides an enhanced visual appearance compared to blue and/or red.

It can be evaluated whether there is a fourth sub-pixel 116 in pixel array 400 that is adjacent, diagonal, or orthogonal (i.e., neighboring) pixels (e.g., pixels 410, 420, and 430) to pixel 440 that has not yet been used for ISR. If the fourth sub-pixel 116 is found, adjacent cell spare repair (NSR) may occur, and the available ISR can be configured to emit green, red, or blue. For example, the fourth sub-pixel 116 in pixels 410, 420, and 430 can be used for a red-configured NSR. As a further example, the fourth sub-pixel 116 in pixels 410, 420, and 430 can be used for a blue-configured NSR.

Although not shown in Figure 4B, if the fourth sub-pixel 116 is not suitable for NSR configuration to emit blue, the blue production in the region of pixel 100A can be compared with the chromaticity threshold of the blue sub-pixel. If the blue production in the region of pixel 100A is equal to or exceeds the chromaticity threshold of the blue sub-pixel, the defective blue sub-pixel is not repaired and no further action is taken. If the blue production in the region of pixel 100A is lower than the chromaticity threshold of the blue sub-pixel, the defective blue sub-pixel can be physically repaired.

Additionally, if the fourth sub-pixel 116 is not used with the NSR to be configured to emit red, the red production in the region of pixel 100A can be compared with the chromaticity threshold of the red sub-pixel. If the red production in the region of pixel 100A is equal to or exceeds the chromaticity threshold of the red sub-pixel, the defective red sub-pixel will not be repaired. If the red production in the region of pixel 100A is lower than the chromaticity threshold of the red sub-pixel, the defective red sub-pixel can be physically repaired. Regardless of whether the red production in the region of pixel 100A is equal to or exceeds the chromaticity threshold of the red sub-pixel, or whether the red production in the region of pixel 100A is lower than the chromaticity threshold of the red sub-pixel, the blue production in the region of pixel 100A can be compared with the chromaticity threshold of the blue sub-pixel. If the blue output in region 100A is equal to or exceeds the chromaticity threshold of the blue subpixel, the defective blue subpixel is not repaired and no further action is taken. If the blue output in region 100A is less than the chromaticity threshold of the blue subpixel, the defective blue subpixel can be physically repaired.

In general, the embodiments disclosed herein typically relate to LED pixels and methods for manufacturing LED pixels that rearrange quantum dot deposits in a color conversion layer to reduce the need for LED pixel repair based on human visual sensitivity. The LED pixels and methods for manufacturing LED pixels can provide individuals with similar visual quality without requiring physical repair and/or replacement of the LED pixels.

Although the foregoing content pertains to embodiments of this disclosure, other and further embodiments of this disclosure may be designed without departing from the basic scope of this disclosure, the scope of which is determined by the appended patent application.

100A: Pixel 104: Subpixel Separation (SI) Structure 105: Well 109: Subpixel 110: Subpixel 112: Subpixel 114: Subpixel 115: Color Conversion Material 115a: Color Conversion Material 115b: Color Conversion Material 115c: Color Conversion Material 115d: Color Conversion Material 116: Subpixel 152: Divider Line

Claims (20)

A method for manufacturing a micro LED display includes the following steps: determining a deposition pattern of a pixel, each pixel comprising at least four sub-pixels, each sub-pixel comprising a sub-pixel isolation structure defining a well, wherein the determining step includes the following steps: identifying a defective sub-pixel, wherein the defective sub-pixel comprises at least one of: a first sub-pixel comprising a first sub-pixel color, a second sub-pixel comprising a second sub-pixel color, or a third sub-pixel comprising a third sub-pixel color, and identifying the defective sub-pixel comprises comparing the first sub-pixel with a color yield threshold, the second sub-pixel with a color yield threshold, and the third sub-pixel with a color yield threshold; identifying an intracell spare. Repair (ISR) subpixels; determining the deposition pattern based on the ISR subpixels and the defective subpixels; and depositing a color-changing material in the ISR subpixels, the color-changing material being configured to emit at least one of the first subpixel color, the second subpixel color, the third subpixel color, or no subpixel color in the ISR subpixels. The method as described in claim 1, wherein the ISR sub-pixel includes a sub-pixel adjacent to the first sub-pixel, the second sub-pixel, or the third sub-pixel. The method as described in claim 1, wherein the ISR sub-pixel includes a sub-pixel that is at an angle to the first sub-pixel, the second sub-pixel, or the third sub-pixel. The method as described in claim 1, wherein the ISR sub-pixel includes a sub-pixel orthogonal to the first sub-pixel, the second sub-pixel, or the third sub-pixel. The method as described in claim 1, wherein the defective sub-pixel includes the first sub-pixel when the first sub-pixel is lower than the chromaticity threshold of the first sub-pixel, the second sub-pixel is higher than the chromaticity threshold of the second sub-pixel, and the third sub-pixel is higher than the chromaticity threshold of the third sub-pixel. The method as described in claim 1, wherein when the first sub-pixel is higher than the chromaticity threshold of the first sub-pixel, the second sub-pixel is lower than the chromaticity threshold of the second sub-pixel, and the third sub-pixel is higher than the chromaticity threshold of the third sub-pixel, the defective sub-pixel includes the second sub-pixel. The method as described in claim 1, wherein when the first sub-pixel is higher than the chromaticity threshold of the first sub-pixel, the second sub-pixel is higher than the chromaticity threshold of the second sub-pixel, and the third sub-pixel is lower than the chromaticity threshold of the third sub-pixel, the defective sub-pixel includes the third sub-pixel. A method for manufacturing a micro LED display includes the following steps: determining a deposition pattern of a pixel, each pixel comprising at least four sub-pixels, each sub-pixel comprising a sub-pixel isolation structure defining a well, wherein the determining step includes the following steps: prioritizing a first sub-pixel comprising a first sub-pixel color over a second sub-pixel comprising a second sub-pixel color and a third sub-pixel comprising a third sub-pixel color based on a first sub-pixel chromaticity threshold; and prioritizing a second sub-pixel comprising the second sub-pixel color based on a second sub-pixel chromaticity threshold. The third sub-pixel, which includes the color of the third sub-pixel, is prioritized over a fourth sub-pixel that does not have a sub-pixel color, based on a third sub-pixel chromaticity threshold; the pixel is formed based on the first sub-pixel chromaticity threshold, the second sub-pixel chromaticity threshold, and the third sub-pixel chromaticity threshold; and a color conversion material configured to emit the first sub-pixel color, the second sub-pixel color, the third sub-pixel color, or not emit a sub-pixel color is deposited in each well according to the deposition pattern. The method as described in claim 8 further includes the step of generating an in-cell alternative repair (ISR) subpixel in the pixel. The method as described in claim 9, wherein the ISR sub-pixel is adjacent to the first sub-pixel, the second sub-pixel, or the third sub-pixel. The method as described in claim 9, wherein the ISR sub-pixel is diagonally angled to the first sub-pixel, the second sub-pixel, or the third sub-pixel. The method as described in claim 9, wherein the ISR sub-pixel is orthogonal to the first sub-pixel, the second sub-pixel, or the third sub-pixel. The method as described in claim 8 further includes the step of: identifying a defective sub-pixel, wherein the defective sub-pixel includes at least one of the following: a first sub-pixel having the first sub-pixel color disposed thereon, a second sub-pixel having the second sub-pixel color disposed thereon, or a third sub-pixel having the third sub-pixel color disposed thereon. The method as described in claim 13, wherein the defective sub-pixel includes the first sub-pixel when the first sub-pixel is lower than the chromaticity threshold of the first sub-pixel, the second sub-pixel is higher than the chromaticity threshold of the second sub-pixel, and the third sub-pixel is higher than the chromaticity threshold of the third sub-pixel. The method as described in claim 13, wherein the defective sub-pixel includes the second sub-pixel when the first sub-pixel is higher than the first sub-pixel's chromaticity threshold, the second sub-pixel is lower than the second sub-pixel's chromaticity threshold, and the third sub-pixel is higher than the third sub-pixel's chromaticity threshold. The method as described in claim 13, wherein the defective sub-pixel includes the third sub-pixel when the first sub-pixel is higher than the first sub-pixel's chromaticity threshold, the second sub-pixel is higher than the second sub-pixel's chromaticity threshold, and the third sub-pixel is lower than the third sub-pixel's chromaticity threshold. A method for manufacturing a microLED display includes the following steps: determining a deposition pattern of a pixel, each pixel comprising at least four sub-pixels, each sub-pixel comprising a microLED and a plurality of sub-pixel isolation structures defining a well, wherein the determining step includes the following steps: identifying a defective microLED, wherein the defective microLED comprises at least one of the following: a first microLED comprising a first sub-pixel color disposed thereon, a second microLED comprising a second sub-pixel color disposed thereon, or a third microLED comprising a third sub-pixel color disposed thereon, and identifying the defective microLED. The defective microLED includes comparing the color of the first sub-pixel with a first sub-pixel chromaticity threshold, the color of the second sub-pixel with a second sub-pixel chromaticity threshold, and the color of the third sub-pixel with a third sub-pixel chromaticity threshold; identifying a standby repair (ISR) microLED within a unit; determining the deposition pattern based on the ISR microLED and the defective microLED; and depositing a color-converting material on top of the ISR microLED, the color-converting material being configured to emit at least one of the first sub-pixel color, the second sub-pixel color, or the third sub-pixel color in the ISR microLED. The method as described in claim 17, wherein the ISR microLED is adjacent to the first microLED, the second microLED, or the third microLED. The method as described in claim 17, wherein the ISR microLED is at an angle to the first microLED, the second microLED, or the third microLED. The method as described in claim 17, wherein the ISR microLED is orthogonal to the first microLED, the second microLED, or the third microLED.