Method for manufacturing backplane for micro-display
Patent Information
- Application Number
- PCT/KR2025/001691
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-03-05
- Filing Date
- 2025-02-05
- Publication Date
- 2025-10-02
AI Technical Summary
Existing manufacturing technologies face challenges in laminating glass substrates onto silicon wafers for microdisplays with high quality and productivity, particularly in maintaining alignment and preventing warping during the process.
A method involving glass substrate preparation, alignment, and attachment steps using UV tape and OCR, followed by ultraviolet curing and dicing saw processes to attach and cut silicon wafers, ensuring precise alignment and protection against moisture and external substances.
The method enhances productivity and prevents glass warping while maintaining high-quality attachment of glass substrates to silicon wafers, resulting in improved microdisplay backplanes.
Smart Images
Figure KR2025001691_02102025_PF_FP_ABST
Abstract
Description
Method for manufacturing a backplane for a microdisplay
[0001] The present invention relates to a method for manufacturing a backplane for a micro display, and more particularly, to a method for manufacturing a backplane for a micro display, which comprises attaching glass to a silicon wafer as a backplane substrate used in a micro display. This application claims the benefit of priority from Korean Patent Application No. 10-2024-0031290, filed on March 5, 2024, the entire contents of which are incorporated herein by reference.
[0002] Rapid advancements in semiconductor technology are miniaturizing various electronic products, including computers. Consequently, this demand for smaller display devices is growing. A microdisplay generally refers to a small display with a screen size of 2 inches or less diagonally. It is defined as a display whose screen size is so small that it requires optical magnification.
[0003] An LCOS (Liquid Crystal on Silicon, hereinafter referred to as 'LCOS') display, a type of reflective micro-display, unlike a typical liquid crystal display, forms liquid crystal cells on a semiconductor substrate, and the semiconductor substrate includes a CMOS circuit for controlling each pixel. In this case, the components and switching circuits of each pixel can be highly integrated and arranged on the semiconductor substrate, and therefore, the LCOS display has the advantage of being able to implement a high resolution of XGA or higher in a small size of about 1 inch. An OLEDoS (Organic Light Emitting Diode on Silicon) display, a type of self-luminous micro-display, also forms an anode electrode, an organic light-emitting layer, and a cathode electrode on a semiconductor substrate, and the semiconductor substrate includes a CMOS circuit for controlling each pixel.
[0004] Typically, the backplane of a large display uses a glass substrate, but the backplane of a micro display uses a silicon substrate to improve characteristics.
[0005] At this time, the backplane for micro displays is made by laminating glass on a silicon substrate.
[0006] Manufacturing technology is needed to laminate glass on silicon wafers and produce backplanes with high quality and productivity to meet the specifications of microdisplays.
[0007] The present invention relates to a method for manufacturing a backplane for a micro display, and provides a method for manufacturing a backplane for a micro display by attaching glass to a silicon wafer as a backplane substrate used in a micro display.
[0008] The technical problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.
[0009] The method for manufacturing a backplane for a micro display of the present invention is as follows:
[0010] A glass substrate preparation step (S10) of preparing multiple glass substrates by cutting a glass plate to a set standard;
[0011] A glass substrate arrangement step (S20) of arranging the plurality of glass substrates at set intervals by adhering them to a UV tape;
[0012] An OCR application step (S30) of applying OCR (optical clear resin) to the plurality of glass substrates;
[0013] An alignment step (S40) in which a plurality of chips are arranged at the above-described set intervals and aligned with the embedded silicon wafer and the plurality of glass substrates facing each other;
[0014] An attachment step (S50) of attaching the silicon wafer and the plurality of glass substrates;
[0015] A curing step (S60) of curing the silicon wafer by irradiating it with ultraviolet rays;
[0016] A tape removal step (S70) for removing the UV tape from the plurality of glass substrates; and
[0017] It may include a cutting step (S80) of cutting the silicon wafer at the set interval to obtain a plurality of backplanes.
[0018] In the glass substrate preparation step (S10) of the method for manufacturing a backplane for a display of the present invention, the glass plate may be prepared to have a size of 6 inches to 12 inches and a thickness of 0.3 mm to 0.7 mm, and may be cut using a dicing saw process.
[0019] In the glass substrate preparation step (S10) of the method for manufacturing a backplane for a display of the present invention, the size of the set standard may be formed to be 0.3 inches to 2 inches.
[0020] In the glass substrate arrangement step (S20) of the method for manufacturing a backplane for a display of the present invention, the UV tape may be supported by a frame of a rigid material to form a plane in which tension is maintained, and the plurality of glass substrates may be arranged on the plane in which tension is maintained.
[0021] In the alignment step (S40) of the method for manufacturing a backplane for a display of the present invention, the plurality of glass substrates and the plurality of chips may be aligned so that their centers face each other through a multi-axis control machine device.
[0022] In the cutting step (S80) of the method for manufacturing a backplane for a display of the present invention, the silicon wafer may be cut such that the boundaries between the plurality of chips are cut using a wet dicing saw process.
[0023] The method for manufacturing a backplane for a micro display of the present invention can protect the chip from moisture and external foreign substances by first attaching a glass substrate and then cutting a silicon wafer using a dicing saw.
[0024] The method for manufacturing a backplane for a micro display of the present invention can be applied using a wet dicing saw by independently attaching each of a plurality of glass substrates.
[0025] The method for manufacturing a backplane for a micro display of the present invention can improve productivity by attaching a plurality of glasses in a single process.
[0026] The method for manufacturing a backplane for a micro display of the present invention can prevent glass warping during operation and improve productivity by applying UV tape and OCR.
[0027] Figure 1 is a block diagram showing a method for manufacturing a backplane for a micro display of the present invention.
[0028] Figure 2 is a photograph showing the glass substrate placement step (S20).
[0029] Figure 3 is a photograph showing the OCR application step (S30).
[0030] Figure 4 is a photograph showing the attachment step (S50).
[0031] Figure 5 is a photograph showing the tape removal step (S70).
[0032] Figure 6 is a photograph showing the solid line area of Figure 5.
[0033] Figure 7 is a photograph showing multiple backplanes after the cutting step (S80).
[0034] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. Throughout this process, the sizes and shapes of components depicted in the drawings may be exaggerated for clarity and convenience. Furthermore, terms specifically defined in consideration of the structure and operation of the present invention may vary depending on the intentions or practices of the user or operator. Definitions of these terms should be based on the overall content of this specification.
[0035] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms “center,” “upper,” “lower,” “left,” “right,” “vertical,” “horizontal,” “inner,” “outer,” “one side,” “other side,” etc., is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present invention is normally placed when used, and is only for the purpose of explaining and briefly explaining the present invention, and does not suggest or imply that the indicated device or element must have a specific orientation and be configured or operated in a specific orientation, and therefore should not be understood as limiting the present invention.
[0036] Fig. 1 is a block diagram illustrating a method for manufacturing a backplane for a microdisplay according to the present invention. Fig. 2 is a photograph illustrating a glass substrate arrangement step (S20). Fig. 3 is a photograph illustrating an OCR application step (S30). Fig. 4 is a photograph illustrating an attachment step (S50). Fig. 5 is a photograph illustrating a tape removal step (S70). Fig. 6 is a photograph illustrating a solid line area in Fig. 5. Fig. 7 is a photograph illustrating a plurality of backplanes after a cutting step (S80).
[0037] Hereinafter, with reference to FIGS. 1 to 7, a method for manufacturing a backplane for a micro display of the present invention will be described.
[0038] As shown in Fig. 1, the method for manufacturing a backplane for a micro display of the present invention is:
[0039] A glass substrate preparation step (S10) of preparing multiple glass substrates by cutting a glass plate to a set standard;
[0040] A glass substrate arrangement step (S20) of arranging the plurality of glass substrates at set intervals by adhering them to a UV tape;
[0041] An OCR application step (S30) of applying OCR (optical clear resin) to the plurality of glass substrates;
[0042] An alignment step (S40) in which a plurality of chips are arranged at the above-described set intervals and aligned with the embedded silicon wafer and the plurality of glass substrates facing each other;
[0043] An attachment step (S50) of attaching the silicon wafer and the plurality of glass substrates;
[0044] A curing step (S60) of curing the silicon wafer by irradiating it with ultraviolet rays;
[0045] A tape removal step (S70) for removing the UV tape from the plurality of glass substrates; and
[0046] It may include a cutting step (S80) of cutting the silicon wafer at the set interval to obtain a plurality of backplanes.
[0047] Hereinafter, the unit “inch” indicating the size of a substrate, etc. may mean the length of a diagonal when the shape of the substrate is a rectangular plane.
[0048] In the above glass substrate preparation step (S10), the glass plate may be prepared to have a size of 6 inches to 12 inches and a thickness of 0.3 mm to 0.7 mm, and may be cut using a dicing saw process. For example, the glass plate may be cut using a dicing saw process to have a size of 8 inches and rearranged on a UV tape.
[0049] In the above glass substrate preparation step (S10), the size of the set standard may be formed to be 0.3 inches to 2 inches. The set standard may be determined in consideration of the standard of the micro display or the standard of the chip embedded in the silicon wafer for the backplane.
[0050] As illustrated in FIG. 2, in the glass substrate arrangement step (S20), the UV tape may be supported by a frame made of a rigid material to form a plane where tension is maintained, and the plurality of glass substrates may be arranged on the plane where tension is maintained. For example, the frame made of a rigid material may have a closed loop shape, more specifically, a ring shape, as illustrated in FIG. 2.
[0051] In the above glass substrate arrangement step (S20), the arrangement of the plurality of glass substrates can be arranged in the same manner as the arrangement of the plurality of chips embedded in the silicon wafer described below using a reconstruction process used in semiconductor manufacturing.
[0052] UV tape may be a PVC, polyolefin, or polyethylene backing material having an adhesive for bonding multiple glass substrates applied to one surface. The thickness of the UV tape may range from 50 to 500 μm, for example, 100 μm, 200 μm, 300 μm, or 400 μm. The adhesiveness of the UV tape may decrease upon exposure to ultraviolet light.
[0053] As illustrated in FIG. 3, in the OCR application step (S30), OCR as an ultraviolet curing material may be applied to one side of a plurality of glass substrates. Specifically, one side of the plurality of glass substrates may be fixed by being adhered to a UV tape, and OCR may be applied to the other side.
[0054] In the above alignment step (S40), the plurality of glass substrates and the plurality of chips may be aligned so that their centers face each other through a multi-axis control mechanism. For example, the plurality of glass substrates and the plurality of chips may be aligned so that their centers face each other through an X, Y, Z, U four-axis control mechanism. The multi-axis control mechanism may be a device that includes two or more power means having different axes and can control them integrally.
[0055] As illustrated in FIG. 4, after being aligned in the alignment step (S40), the plurality of glass substrates and the silicon wafer can be attached to each other in close contact in the attachment step (S50).
[0056] In the above curing step (S60), the OCR is cured by exposure to light having a wavelength of 100 nm to 400 nm, and the adhesive strength of the UV tape may be reduced.
[0057] As illustrated in FIG. 5, in the tape removal step (S70), the UV tape that has lost its adhesive strength can be removed from a plurality of glass substrates.
[0058] As illustrated in FIG. 6, a plurality of glass substrates that are well aligned and bonded to a silicon wafer may not cover the boundaries (cut lines) between a plurality of chips embedded in the silicon wafer.
[0059] As illustrated in FIG. 7, in the cutting step (S80), the silicon wafer can be manufactured into a plurality of backplanes by cutting the boundaries between the plurality of chips using a wet dicing saw process.
[0060] While the embodiments of the present invention have been described above, they are merely exemplary, and those skilled in the art will appreciate that various modifications and equivalent embodiments are possible. Therefore, the true technical protection scope of the present invention should be defined by the following claims.
Claims
1. A glass substrate preparation step (S10) of preparing multiple glass substrates by cutting a glass plate to a set standard; A glass substrate arrangement step (S20) of arranging the plurality of glass substrates at set intervals by adhering them to a UV tape; An OCR application step (S30) of applying OCR (optical clear resin) to the plurality of glass substrates; An alignment step (S40) in which a plurality of chips are arranged at the above-described set intervals and aligned with the embedded silicon wafer and the plurality of glass substrates facing each other; An attachment step (S50) of attaching the silicon wafer and the plurality of glass substrates; A curing step (S60) of curing the silicon wafer by irradiating it with ultraviolet rays; A tape removal step (S70) for removing the UV tape from the plurality of glass substrates; and A method for manufacturing a backplane for a micro display, comprising a cutting step (S80) of cutting the silicon wafer at the set interval to obtain a plurality of backplanes.
2. In paragraph 1, In the above glass substrate preparation step (S10), A method for manufacturing a backplane for a micro display, wherein the glass plate is prepared to have a size of 6 inches to 12 inches and a thickness of 0.3 mm to 0.7 mm and is cut using a dicing saw process.
3. In paragraph 1, In the above glass substrate preparation step (S10), A method for manufacturing a backplane for a micro display, wherein the size of the above-mentioned setting standard is formed to be 0.3 inches to 2 inches.
4. In paragraph 1, In the above glass substrate arrangement step (S20), The above UV tape is supported by a frame of rigid material to form a plane that maintains tension, A method for manufacturing a backplane for a micro display, wherein the plurality of glass substrates are arranged on a plane where tension is maintained.
5. In paragraph 1, In the above sorting step (S40), A method for manufacturing a backplane for a micro display, wherein the plurality of glass substrates and the plurality of chips are aligned so that their centers face each other through a multi-axis control machine device.
6. In paragraph 1, In the above cutting step (S80), A method for manufacturing a backplane for a micro display, wherein the silicon wafer is cut at the boundaries between the plurality of chips using a wet dicing saw process.