Pixel shallow-pit glass substrate for flow magnetic mass transfer and manufacturing method of pixel shallow-pit glass substrate

Abstract

The invention discloses a pixel shallow pit glass substrate for flow magnetic mass transfer and a manufacturing method, and belongs to the technical field of microelectronic device manufacturing, the substrate comprises an A-layer glass substrate and a B-layer glass substrate arranged above the A-layer glass substrate, and the method comprises the following steps: preparing the A-layer glass substrate and the B-layer glass substrate; processing a through hole and an MAC (Media Access Control) positioning mark point I of the A-layer glass substrate; preparing a copper powder-PVB (Polyvinyl Butyral) homogeneous slurry; sintering pins on the A-layer glass substrate; processing a B-layer glass substrate through hole and a second MAC positioning mark point; the A-layer glass substrate and the B-layer glass substrate are aligned and compounded; and performing hot-pressing fusion to form the composite substrate. By adopting the structure and the manufacturing method, the invention has the characteristics of high precision, low cost and batch production.

Description

Technical Field

[0001] The present invention relates to the technical field of microelectronic device manufacturing, and in particular to a pixel shallow pit glass substrate for massive magnetic flux transfer and a manufacturing method thereof. Background Art

[0002] Micro-LED (micro-light-emitting diode) display technology, with its high brightness, high contrast, low power consumption, and long lifespan, is considered a core technology for next-generation display technology. To achieve high-resolution and ultra-high pixel density Micro-LED display panels, mass transfer technology has become a key process bottleneck. This requires efficiently and accurately transferring millions to billions of micron-sized R / G / B chips to the designated pixel locations on the target driver substrate. Current mainstream mass transfer technologies each have their limitations. Elastic stamp transfer technology, which uses a flexible material array to adsorb and imprint the chips onto a substrate, is relatively low-cost, but is limited by stamp deformation and adhesion control, making transfer speed difficult to achieve. Furthermore, positioning accuracy for small chips is subject to significant error. Laser lift-off technology, which utilizes laser energy to break the bond between the chip and the growth substrate, enables high-speed transfer, but laser thermal effects can easily damage the chip's internal quantum wells, resulting in poor wavelength uniformity. Electrostatic adsorption technology, which uses an electric field to control chip movement, theoretically achieves submicron accuracy, but ambient humidity or surface charge accumulation on the substrate significantly reduces adsorption stability, resulting in generally below 90% yield in mass production. Fluid self-assembly technology relies on the synergistic effect of fluid forces and surface tension, requiring the chip to undergo hydrophilic and hydrophobic modification pretreatment. The process is highly complex, and the assembly speed is limited by the fluid viscosity coefficient, making it difficult to meet production capacity requirements. Among the many transfer technologies, fluid magnetic self-assembly technology stands out due to its unique fluid dynamics and magnetic force collaborative positioning mechanism. This method immerses the chip in a fluid, where the fluid flow drives the chip movement and a precise magnetic field completes the chip positioning. This allows the Micro-LED chip to autonomously arrange itself to the predetermined position in the dynamic flow field, enabling the transfer of tens of thousands of chips at a time. While achieving the mixing of color chips of different wavelengths, it also achieves a truly massive transfer of chips of different sizes. Furthermore, compared to traditional mechanical pickup or electrostatic adsorption technologies, fluid magnetic self-assembly significantly improves transfer efficiency while compressing the positioning error of a single chip to the submicron level, making it particularly suitable for the large-scale manufacturing of large-scale display devices.

[0003] In the technology of mass transfer of flux magnetics, the processing accuracy and morphology control of the shallow pits of the substrate are the core factors that determine the reliability of chip positioning. The main problems faced by the existing mass transfer technology of flux magnetics include insufficient adaptability of the substrate, the lack of physical limiting structure of the traditional planar substrate, and the chip is easily affected by turbulent disturbances or uneven magnetic distribution in the flow field, resulting in posture offset or position drift, which significantly reduces the transfer yield. In addition, when laser direct writing (such as CO2 laser or nanosecond ultraviolet laser) is used to directly etch shallow pits on the glass substrate, the high heat input causes local melting and re-solidification of the glass, resulting in excessive inclination of the side walls of the shallow pits, causing poor contact between the chip pins and the side walls of the shallow pits, and increased resistance fluctuation rate. The existing application for invention patent CN202410878847.3 "A trapezoidal LED chip electromagnetic directional falling flux magnetic self-assembly mechanism and method" uses a trapezoidal structure chip to control the chip's posture in the flow field, but this method is only applicable to specific chips, the cost is greatly increased, and market application is difficult. The existing invention patent application CN202411331903.8, "A magnetic correction device and transfer method for local array LED chips for fluid mass transfer," corrects the LED chips that have failed to transfer on the transfer substrate within the correction platform. It has the advantages of high adjustment accuracy, no damage to the chip, and reusability. However, this method can only correct the offset chip after the transfer is completed and fails to avoid the chip offset problem. The existing invention patent application CN202411687195.1, "A method for making a through-glass hole," optimizes the laser processing parameters to meet the ultra-high aspect ratio requirements of the through-glass hole, but focuses on the through-hole aspect ratio rather than the shallow pit morphology control. When used directly for shallow pit processing, the laser thermal effect causes the shallow pit sidewall to be too tilted, the heat-affected zone (HAZ) to be too large, and the bottom roughness to be too large, resulting in excessive tilt angle deviation after the Micro-LED chip is inserted, and the transfer yield is too low. Therefore, to address the chip posture offset and position drift problems in the existing fluid magnetic mass transfer technology, a low-cost, high-precision, and batch-compatible solution is urgently needed. Summary of the Invention

[0004] The purpose of the present invention is to provide a pixel shallow pit glass substrate for mass transfer of magnetic flux and a manufacturing method thereof, so as to solve the problems mentioned in the background technology.

[0005] To achieve the above-mentioned objectives, the present invention provides a pixel shallow pit glass substrate for mass transfer of magnetic flux, comprising a layer A glass substrate and a layer B glass substrate arranged above the layer A glass substrate, the layer A glass substrate comprising a plurality of pixel units 1, each of the pixel units comprising six circular through holes, the circular through holes being filled with sintered copper powder to form positive and negative pins, MAC positioning mark points 1 being provided on both side edges of the layer A glass substrate, the layer B glass substrate being provided with the same number of pixel units 1 and corresponding one to one with the pixel units 1, each of the pixel units 2 being provided with three rectangular through holes, and MAC positioning mark points 2 being provided on both side edges of the layer B substrate being provided coaxially with the MAC positioning mark points.

[0006] Preferably, the A-layer glass substrate is made of soda-lime glass and has a thickness of 0.1 mm.

[0007] Preferably, the B-layer glass substrate is made of soda-lime glass with a thickness of 0.08 mm.

[0008] Preferably, the A layer glass substrate and the B layer glass substrate are fused by vacuum hot pressing to form a composite substrate, the positive and negative pins and the rectangular through holes form a shallow pit structure, the shallow pit structure has a depth of 0.08 mm, and a side wall inclination angle ≤0.8°.

[0009] The present invention also provides a method for manufacturing a pixel shallow pit glass substrate for mass transfer of magnetic flux, the steps comprising:

[0010] S1. Prepare a 0.1 mm thick layer A glass substrate and a 0.08 mm thick layer B glass substrate using a float glass process, wherein both the layer A glass substrate and the layer B glass substrate are made of soda-lime glass and have a surface flatness of ≤0.1 μm / mm;

[0011] S2. Use ultraviolet pulse laser to process circular through holes on the A-layer glass substrate, with six through holes processed for each pixel unit, and process MAC positioning mark points one on both sides of the A-layer glass substrate;

[0012] S3, mixing the copper powder with the binder, adding an ethanol / acetone mixed solvent, and then ultrasonically dispersing the mixture. The mixture is then ground with three rollers to a viscosity of 8000-12000 cP to form a homogeneous slurry to fill the circular through-hole;

[0013] S4, filling the circular through holes of the A-layer glass substrate with a homogeneous slurry, drying the slurry in a stepwise manner, and then sintering the copper powder to form positive and negative pins;

[0014] S5. Using the same laser parameters, process rectangular through holes on the B-layer glass substrate, processing three rectangular through holes for each pixel unit, and process a second MAC positioning mark point coaxial with the MAC positioning mark point on the edge of the B-layer glass substrate;

[0015] S6. Using an optical camera to identify the MAC positioning mark point 1 and the MAC positioning mark point 2, and using a closed-loop feedback system to correct the offset in real time, thereby optimizing the alignment error between the center of the rectangular through hole and the center of the positive and negative pins;

[0016] S7. Composite the A-layer glass substrate and the B-layer glass substrate into a composite substrate through a vacuum hot pressing process. After the composite, the rectangular through-holes and the positive and negative pins form a shallow pit structure with a depth of 0.08 mm and a side wall inclination angle of ≤0.8°. Cool the composite substrate after hot pressing.

[0017] Preferably, the shape of the circular through hole in step S2 matches the R / G / B chip and the aperture tolerance does not exceed 2 μm, and the size of the MAC positioning mark point is 50 μm×50 μm.

[0018] Preferably, the copper powder in step S3 is spherical copper powder with a diameter of 2-3 μm, accounting for 95 wt %, with a copper purity of ≥99.9%, and the binder is polyvinyl butyral, accounting for 5 wt %.

[0019] Preferably, the stepwise drying at elevated temperatures in step S4 includes drying at 80° C. / 120° C. / 150° C. for 30 minutes each.

[0020] Preferably, the side length of the rectangular through hole in step S5 is equal to 1.15 times the side length of the R / G / B chip, and the tolerance does not exceed 1 μm, and the center of the rectangular through hole is aligned with the center of the positive and negative pins with an error of no more than 1 μm.

[0021] Preferably, in step S7, the composite substrate after hot pressing and fusion is cooled to 300°C at a cooling rate of 2°C / min and then naturally cooled to room temperature.

[0022] Therefore, the present invention adopts the above-mentioned pixel shallow pit glass substrate for mass transfer of magnetic flux and the manufacturing method, which has the following beneficial effects:

[0023] (1) While ensuring that the chip is fixed smoothly and quickly in the designated position, it overcomes the problems of poor vertical positioning accuracy of the Micro-LED chip caused by the tilted sidewalls of the shallow pits formed by traditional laser ablation, and the high cost of the dry etching process requiring a mask;

[0024] (2) The geometric shape of the shallow pits is directly defined by combining the rectangular through-holes of the B-layer glass substrate with the pins of the A-layer glass substrate. Combined with the MAC optical alignment and copper powder sintering process, high-precision vertical shallow pits (sidewall inclination angle ≤ 0.8°) are batch-produced to avoid the taper effect of laser ablation.

[0025] (3) Using MAC positioning markers and optical cameras to form a closed-loop feedback system to correct the position offset of the A / B layer in real time;

[0026] (4) The thermal expansion coefficients of the positive and negative pins match those of the glass, improving the yield of mass transfer;

[0027] (5) The dry etching mask process is eliminated, the processing cost of the single-chip substrate is reduced, and the processing efficiency is improved.

[0028] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic top view of the A-layer glass substrate structure of the present invention;

[0030] Figure 2 Schematic top view of the B-layer glass substrate structure of the present invention;

[0031] Figure 3 This is a schematic diagram of the composite spatial structure of the A-layer glass substrate and the B-layer substrate in alignment with each other in the present invention;

[0032] Figure 4 Schematic top view of the composite glass substrate of the present invention;

[0033] Figure 5 Schematic cross-sectional view of the composite substrate structure of the present invention;

[0034] Figure 6 is a flow chart of the manufacturing method of the present invention;

[0035] Figure 7 This is a cross-sectional view of a shallow pit (side wall inclination angle ≤ 0.8°) according to the present invention;

[0036] Figure 8 Cross-sectional view of a shallow pit (sidewall inclination angle > 3°) directly processed using conventional lasers

[0037] Reference numerals

[0038] 101. Glass substrate layer A; 102. Circular through-hole; 103. Positive and negative pins; 104. MAC positioning mark point 1; 201. Glass substrate layer B; 202. Rectangular through-hole; 203. MAC positioning mark point 2; 301. Composite substrate; 302. Shallow pit structure; 303. Sidewall inclination angle. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "upper", "lower", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or is the orientation or position relationship in which the product of the invention is usually placed when in use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0040] Example

[0041] Reference Figure 1-5 The present invention provides a pixel shallow pit glass substrate for magnetic flux mass transfer, comprising a layer A glass substrate 101 and a layer B glass substrate 201 disposed above the layer A glass substrate 101. The layer A glass substrate 101 is made of soda-lime glass and has a thickness of 0.1 mm. The layer B glass substrate 201 is made of the same soda-lime glass as the layer A glass substrate 101 and has a thickness of 0.08 mm.

[0042] The A-layer glass substrate 101 includes 16 pixel units 1, with every 4 pixel units 1 forming a group equidistantly distributed on the A-layer glass substrate 101. Each pixel unit includes six circular through holes 102, the hole depth of which penetrates the A-layer glass substrate 101. The circular through holes 102 are filled with sintered copper powder to form positive and negative pins 103. A MAC positioning mark point 104 is set on both sides of the edge of the A-layer glass substrate 101.

[0043] The B layer glass substrate 201 is provided with 16 pixel units 2, corresponding to the pixel units 1, each pixel unit 2 is provided with three rectangular through holes 202, and the edges of the B layer substrate are provided with MAC positioning mark points 2 203 coaxially arranged with the MAC positioning mark point 1 104.

[0044] The A-layer glass substrate 101 and the B-layer glass substrate 201 are fused by vacuum hot pressing to form a composite substrate 301 . The positive and negative pins 103 and the rectangular through-holes 202 form a shallow pit structure 302 . The shallow pit structure 302 has a depth of 0.08 mm and a sidewall inclination angle 303 ≤ 0.8°.

[0045] Reference Figure 6 The present invention also provides a method for manufacturing a pixel shallow pit glass substrate for mass transfer of magnetic flux, the steps comprising:

[0046] S1. Prepare a layer A glass substrate 101 and a layer B glass substrate 201: Use a float process to prepare a layer A glass substrate 101 with a thickness of 0.1 mm and a layer B glass substrate 201 with a thickness of 0.08 mm. Both the layer A glass substrate 101 and the layer B glass substrate 201 are made of soda-lime glass, and have a surface flatness of ≤0.1 μm / mm.

[0047] Soda lime glass has a high absorption coefficient (>10 4 cm -1 ), 355nm laser can be efficiently absorbed by the surface layer of the glass substrate at a depth of 50nm, achieving a heat-affected zone of <1μm, avoiding microcracks, and the through-hole sidewall roughness Ra≤0.5μm.

[0048] S2. Processing of through holes and positioning mark points on the A-layer glass substrate 101: A circular through hole 102 is processed on the A-layer glass substrate 101 using an ultraviolet pulse laser. The parameters of the ultraviolet pulse laser are: laser wavelength 355 nm, pulse width 10 ps, ​​repetition frequency 100 kHz, and laser energy density 5 J / cm 2 , with a scanning speed of 500 mm / s. Six through-holes are machined into each pixel unit. The circular through-hole 102 matches the shape of the R / G / B chip and has an aperture tolerance of ±2 μm. MAC positioning mark points 104 are machined on both sides of the edge of the A-layer glass substrate 101, with a mark size of 50 μm × 50 μm.

[0049] S3. Preparation of copper powder-PVB homogeneous slurry: copper powder is mixed with a binder, wherein the binder is polyvinyl butyral (PVB), accounting for 5wt%, and the copper powder is spherical copper powder with a particle size of 2-3μm, accounting for 95wt%, with a copper purity of ≥99.9% and a resistivity of <1×10 -6 Ω·m, an ethanol / acetone mixed solvent (volume ratio 1:1, accounting for 20-25% of the total solid-liquid mass) was added and ultrasonically dispersed, and then rolled by three rollers to a viscosity of 8000-12000 cP to form a homogeneous slurry to fill the circular through-hole 102.

[0050] S4. Sintering pins on glass substrate A 101: A homogeneous slurry is filled into the circular through-holes 102 of glass substrate A 101. After drying in a stepwise manner (80°C / 120°C / 150°C for 30 minutes each), copper powder is sintered to form positive and negative pins 103. After the stepwise drying, the PVB is gradually desolvated and a temporary bonding network is formed. The sintering conditions are an H2 / N2 mixed gas atmosphere (4:96 by volume), a temperature of 600°C, and a time of 30 minutes. After sintering, the copper layer has a density ≥98.5% of the theoretical value, an ash content <0.1 wt%, and a tensile strength of >150 MPa for the positive and negative pins 103.

[0051] S5. Processing of through-holes and positioning markers on the B-layer glass substrate 201: On the B-layer glass substrate 201, rectangular through-holes 202 are processed using the same laser parameters. Three rectangular through-holes 202 are processed for each pixel unit. The side length of the square through-holes is 1.15D ± 1 μm (D is the side length of the R / G / B chip). This ensures accurate positioning of the R / G / B chips during mass transfer. The center of the through-hole is aligned with the center of the positive and negative pins 103 on the A-layer with an error of ≤ 1 μm. MAC positioning marker 2 203 is then processed on the edge of the B-layer glass substrate 201, coaxial with MAC positioning marker 1 104.

[0052] S6. Alignment: A 5μm resolution optical camera is used to identify MAC positioning marker 104 and MAC positioning marker 203. A closed-loop feedback system is used to correct offsets in real time, optimizing the alignment error between the center of the rectangular through-hole 202 and the center of the positive and negative pins 103. This reduces the alignment error between the A / B layer through-hole center from ≤1μm to ≤0.9μm (3σ value). The closed-loop feedback system has a correction frequency of ≥100Hz and a dynamic offset compensation accuracy of ±0.1μm.

[0053] S7. Hot Pressing Fusion: The A-layer glass substrate 101 and the B-layer glass substrate 201 are combined into a composite substrate 301 through a vacuum hot pressing process. After the combination, the rectangular through-hole 202 and the positive and negative pins 103 form a shallow pit structure 302. The shallow pit structure 302 has a depth of 0.08mm and a sidewall inclination angle 303 of ≤0.8°. The hot-pressed composite substrate 301 is cooled to 300°C at a cooling rate of 2°C / min and then naturally cooled to room temperature to eliminate stress within the substrate. The vacuum degree required for vacuum hot pressing is ≤1×10-3Pa to avoid oxidation and impurity contamination. The hot pressing temperature is 700°C ± 5°C to soften the glass substrates and achieve molecular-level bonding. A pressure of 5MPa ± 0.2MPa is applied to ensure that the through-hole sidewalls of the A-layer glass substrate 101 and the B-layer glass substrate 201 are completely bonded. The holding time is 30 minutes ± 1 minute to ensure sufficient interface diffusion and no excessive deformation of the glass.

[0054] S8. Detection of the composite substrate 301: Use a white light interferometer to measure the shallow pit structure 302, and its side wall tilt angle 303 is ≤ 0.8° (measurement tolerance ± 0.05°); use a high-precision image matching algorithm to calculate the A / B layer through-hole alignment accuracy, and its alignment accuracy is ≤ 0.9μm (3σ value); use a laser scanner to detect the warpage, and the warpage of the composite substrate 301 at 25°C is ≤ 0.05mm / m 2 ; Use SEM to observe the gap between the positive and negative pins and the glass substrate, and the gap is <0.2μm; perform stability testing by cycling 100 times from -40℃ to 85℃, and after the test, the change in shallow pit size is <0.1μm, ensuring the stability of the composite substrate 301.

[0055] It should be noted that if the material of the glass substrate changes, the laser parameters, vacuum degree and hot pressing temperature will also change accordingly. For example, if it is changed to borosilicate glass, the laser energy density needs to be increased to 6J / cm 2 , the hot pressing temperature is adjusted to 715℃±10℃, and the vacuum degree ≤1×10-3Pa remains unchanged, but the holding time needs to be extended to 40 minutes.

[0056] Reference Figure 7 and Figure 8 The cross-sectional view of the invented shallow pit (side wall inclination angle ≤ 0.8°) and the traditional laser directly processed shallow pit (side wall inclination angle > 3°) is shown. By comparison, it can be seen that the inclination angle of the shallow pit side wall is significantly reduced (from > 3° to ≤ 0.8°), thereby reducing the vertical installation angle error of the Micro-LED.

[0057] Therefore, the present invention adopts the above-mentioned pixel shallow pit glass substrate and manufacturing method for mass transfer of magnetic flux, which can ensure that the chip is fixed in the specified position smoothly and quickly, while overcoming the problems of poor vertical positioning accuracy of Micro-LED chips caused by the tilted side walls of the shallow pits formed by traditional laser ablation, and the dry etching process requiring a mask and high cost.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A pixel shallow pit glass substrate for mass transfer of magnetic flux, characterized by: It includes a layer A glass substrate and a layer B glass substrate arranged above the layer A glass substrate, the layer A glass substrate includes multiple pixel units 1, each of the pixel units includes six circular through holes, the circular through holes are filled with sintered copper powder to form positive and negative pins, MAC positioning mark points 1 are set on both sides of the edge of the layer A glass substrate, the layer B glass substrate is provided with the same number of pixel units 2 as the pixel units 1 and one-to-one corresponding, each of the pixel units 2 is provided with three rectangular through holes, and MAC positioning mark points 2 are set on both sides of the edge of the layer B substrate coaxially with the MAC positioning mark points.

2. The pixel shallow pit glass substrate for mass transfer of magnetic flux according to claim 1, characterized in that: The A-layer glass substrate is made of soda-lime glass and has a thickness of 0.1 mm.

3. The pixel shallow pit glass substrate for mass transfer of magnetic flux according to claim 1, characterized in that: The B-layer glass substrate is made of soda-lime glass and has a thickness of 0.08 mm.

4. The pixel shallow pit glass substrate for mass transfer of magnetic flux according to claim 1, characterized in that: The A-layer glass substrate and the B-layer glass substrate are fused by vacuum hot pressing to form a composite substrate. The positive and negative pins and the rectangular through holes form a shallow pit structure with a depth of 0.08 mm and a side wall inclination angle of ≤0.8°.

5. The method for manufacturing a pixel shallow pit glass substrate for mass transfer of magnetic flux according to any one of claims 1 to 4, characterized in that the steps include: S1. Prepare a 0.1 mm thick layer A glass substrate and a 0.08 mm thick layer B glass substrate using a float glass process, wherein both the layer A glass substrate and the layer B glass substrate are made of soda-lime glass and have a surface flatness of ≤0.1 μm / mm; S2. Use ultraviolet pulse laser to process circular through holes on the A-layer glass substrate, with six through holes processed for each pixel unit, and process MAC positioning mark points one on both sides of the A-layer glass substrate; S3, mixing the copper powder with the binder, adding an ethanol / acetone mixed solvent, and then ultrasonically dispersing the mixture. The mixture is then ground with three rollers to a viscosity of 8000-12000 cP to form a homogeneous slurry to fill the circular through-hole; S4, filling the circular through holes of the A-layer glass substrate with a homogeneous slurry, drying the slurry in a stepwise manner, and then sintering the copper powder to form positive and negative pins; S5. Using the same laser parameters, process rectangular through holes on the B-layer glass substrate, processing three rectangular through holes for each pixel unit, and process a second MAC positioning mark point coaxial with the MAC positioning mark point on the edge of the B-layer glass substrate; S6. Using an optical camera to identify the MAC positioning mark point 1 and the MAC positioning mark point 2, and using a closed-loop feedback system to correct the offset in real time, thereby optimizing the alignment error between the center of the rectangular through hole and the center of the positive and negative pins; S7. Composite the A-layer glass substrate and the B-layer glass substrate into a composite substrate through a vacuum hot pressing process. After the composite, the rectangular through-holes and the positive and negative pins form a shallow pit structure with a depth of 0.08 mm and a side wall inclination angle of ≤0.8°. Cool the composite substrate after hot pressing.

6. The method for manufacturing a pixel shallow pit glass substrate for mass transfer of magnetic flux according to claim 5, characterized in that: The shape of the circular through hole in step S2 matches the R / G / B chip and the aperture tolerance does not exceed 2 μm, and the size of the MAC positioning mark point is 50 μm×50 μm.

7. The method for manufacturing a pixel shallow pit glass substrate for mass transfer of magnetic flux according to claim 5, characterized in that: The copper powder in step S3 is spherical copper powder with a diameter of 2-3 μm, accounting for 95 wt % and a copper purity of ≥99.9%. The binder is polyvinyl butyral, accounting for 5 wt %.

8. The method for manufacturing a pixel shallow pit glass substrate for mass transfer of magnetic flux according to claim 5, characterized in that: The stepwise drying in step S4 includes drying at 80°C / 120°C / 150°C for 30 minutes each.

9. The method for manufacturing a pixel shallow pit glass substrate for mass transfer of magnetic flux according to claim 5, characterized in that: In step S5, the side length of the rectangular through hole is equal to 1.15 times the side length of the R / G / B chip, and the tolerance does not exceed 1 μm. The center of the rectangular through hole is aligned with the center of the positive and negative pins with an error of no more than 1 μm.

10. The method for manufacturing a pixel shallow pit glass substrate for mass transfer of magnetic flux according to claim 5, characterized in that: In step S7 , the composite substrate after hot pressing and fusion is cooled to 300° C. at a cooling rate of 2° C. / min and then naturally cooled to room temperature.

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