# US 12,193,157 B2 · Display screen and manufacturing method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,193,157 B2 - Document ID: US12193157B2 - Status: Granted - Kind: B2 - Application number: 17/779,836 - Filed: 2022-04-24 - Published: 2024-05-30 - Granted: 2025-01-07 - Earliest claimed: 2022-04-12 - Assignees: Wuhan China Star Optoelectronics Semiconductor Display Technology Co., Ltd. - Applicants: Wuhan China Star Optoelectronics Semiconductor Display Technology Co., Ltd. - Inventors: Chengsheng Luo; Tiyao Ma; Yingchuan Jiang; Wenxu Xianyu - Web page: https://patentgrep.com/patent/US12193157B2 ## CPC - H05K 1/144: {Stacked arrangements of planar printed circuit boards} - H05K 3/323: {by applying an anisotropic conductive adhesive layer over an array of pads} - C09J 5/00: Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers - C09J 9/02: Electrically-conducting adhesives - H05K 1/14: Structural association of two or more printed circuits (providing electric connection to or between printed circuits H05K1/11, H01R12/00) - H05K 3/368: {parallel to each other (H05K3/361 takes precedence)} - C08K 7/06: Elements - C08K 2003/0806: {Silver} - C08K 2201/001: Conductive additives - C08K 2201/011: Nanostructured additives - C09J 2203/318: for the production of liquid crystal displays - C09J 2301/314: the adhesive layer and/or the carrier being conductive - C09J 2301/408: additives as essential feature of the adhesive layer - C09J 2463/00: Presence of epoxy resin - G09F 9/3026: {Video wall, i.e. stackable semiconductor matrix display modules (video wall control systems G06F3/1446, G09G2300/026)} - H05K 2201/041: Stacked PCBs, i.e. having neither an empty space nor mounted components in between - H05K 2201/10128: Display - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - C09J: ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES (preparation of glue or gelatine C09H) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - G09F: DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS ## Abstract A display screen and a manufacturing method thereof are disclosed. A first conductive adhesive and a second conductive adhesive are disposed between a daughter board and a mother board. A first adhesive force is formed between the first conductive adhesive and the daughter board, a second adhesive force is formed between the first conductive adhesive and the second conductive adhesive, and a third adhesive force is formed between the second conductive adhesive and the mother board. A technical problem of the daughter board and the mother board being difficult to separate for rework after assembly can be solved by allowing both the first adhesive force and the second adhesive force to be greater than the third adhesive force. ## Claims ### Claim 1 A display screen, comprising: a mother board; at least one daughter board disposed opposite to the mother board; a first conductive adhesive disposed between the mother board and the at least one daughter board, wherein a first adhesive force is formed between the first conductive adhesive and the at least one daughter board, wherein a material of the first conductive adhesive comprises a first matrix resin and a first conductor, and the first matrix resin comprises a polar group; and a second conductive adhesive disposed between the first conductive adhesive and the mother board, wherein the second conductive adhesive is in direct contact with the first conductive adhesive, a second adhesive force is formed between the first conductive adhesive and the second conductive adhesive, and a third adhesive force is formed between the second conductive adhesive and the mother board, a material of the second conductive adhesive comprises a second matrix resin and a second conductor, and the second matrix resin comprises another polar group; wherein both the first adhesive force and the second adhesive force are greater than the third adhesive force. ### Claim 2 (depends on 1) The display screen according to claim 1, wherein a content of the first matrix resin in the first conductive adhesive is greater than a content of the second matrix resin in the second conductive adhesive. ### Claim 3 (depends on 2) The display screen according to claim 2, wherein the material of the first conductive adhesive comprises 8 wt % to 22 wt % of the first matrix resin, and the material of the second conductive adhesive comprises 3 wt % to 17 wt % of the second matrix resin. ### Claim 4 (depends on 1) The display screen according to claim 1, wherein a morphology of the first conductor is non-granular. ### Claim 5 (depends on 4) The display screen according to claim 4, wherein the morphology of the first conductor is linear, branched, or scale-like. ### Claim 6 (depends on 1) The display screen according to claim 1, wherein a morphology of the second conductor is granular. ### Claim 7 (depends on 1) The display screen according to claim 1, wherein the at least one daughter board is provided with a first bonding pad, and the first conductive adhesive is connected to the first bonding pad; the mother board is provided with a second bonding pad, and the second conductive adhesive is connected to the second bonding pad; and the first bonding pad is electrically connected to the second bonding pad by the first conductive adhesive and the second conductive adhesive. ### Claim 8 (depends on 7) The display screen according to claim 7, wherein the at least one daughter board is defined with a groove corresponding to the first bonding pad, the first bonding pad is disposed at a bottom of the groove, the first conductive adhesive covers the groove, and a surface of the first conductive adhesive away from the first bonding pad is beyond an opening of the groove. ### Claim 9 (depends on 8) The display screen according to claim 8, wherein a part of the first conductive adhesive beyond the opening of the groove has a width greater than a width of the groove. ### Claim 10 A manufacturing method of a display screen, comprising following steps: a step B1: providing a mother board and at least one daughter board; a step B2: disposing a first conductive adhesive on the at least one daughter board, wherein a first adhesive force is formed between the first conductive adhesive and the at least one daughter board, wherein a material of the first conductive adhesive comprises a first matrix resin and a first conductor, and the first matrix resin comprises a polar group; a step B3: disposing a second conductive adhesive on the first conductive adhesive, wherein the second conductive adhesive is in direct contact with the first conductive adhesive, a second adhesive force is formed between the first conductive adhesive and the second conductive adhesive, a material of the second conductive adhesive comprises a second matrix resin and a second conductor, and the second matrix resin comprises another polar group; and a step B4: assembling the mother board and the at least one daughter board, wherein the first conductive adhesive and the second conductive adhesive are disposed between the mother board and the at least one daughter board, a third adhesive force is formed between the second conductive adhesive and the mother board, and both the first adhesive force and the second adhesive force are greater than the third adhesive force. ### Claim 11 (depends on 10) The manufacturing method of the display screen according to claim 10, wherein the step B2 comprises: a step B21: disposing a first conductive paste on the at least one daughter board; and a step B22: curing the first conductive paste to obtain the first conductive adhesive. ### Claim 12 (depends on 11) The manufacturing method of the display screen according to claim 11, wherein the step B3 comprises a step of disposing a second conductive paste on the first conductive adhesive to form the second conductive adhesive; and a content of the first matrix resin in the first conductive paste is greater than a content of the second matrix resin in the second conductive paste. ### Claim 13 (depends on 12) The manufacturing method of the display screen according to claim 12, wherein the first conductive paste comprises 10 wt % to 20 wt % of the first matrix resin, and the second conductive paste comprises 5 wt % to 15 wt % of the second matrix resin. ### Claim 14 (depends on 10) The manufacturing method of the display screen according to claim 10, wherein a morphology of the first conductor is non-granular. ### Claim 15 (depends on 14) The manufacturing method of the display screen according to claim 14, wherein the morphology of the first conductor is linear, branched, or scale-like. ### Claim 16 (depends on 10) The manufacturing method of the display screen according to claim 10, wherein a morphology of the second conductor is granular. ### Claim 17 (depends on 12) The manufacturing method of the display screen according to claim 12, wherein in the step B4, after assembling the mother board and the at least one daughter board, the second conductive adhesive is pre-cured. ### Claim 18 (depends on 17) The manufacturing method of the display screen according to claim 17, further comprising following steps: a step B5: conducting an electrical test on the first conductive adhesive and the second conductive adhesive, proceeding to a step B6 if conductive properties of the first conductive adhesive and the second conductive adhesive are qualified, and proceeding to a step B7 if the conductive properties of the first conductive adhesive and the second conductive adhesive are abnormal; the step B6: post-curing the second conductive adhesive; and the step B7: separating the mother board from the at least one daughter board, cleaning the mother board and the at least one daughter board, and repeating the steps B3 to B5.