# US 12,772,374 B2 · Circuit board having a switch and method for fabricating the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,772,374 B2 - Document ID: US12772374B2 - Status: Granted - Kind: B2 - Application number: 18/929,000 - Filed: 2024-10-28 - Published: 2026-04-30 - Granted: 2026-10-20 - Earliest claimed: 2024-10-28 - Assignees: HongQiSheng Precision Electronics (QinHuangDao) Co., Ltd.; Avary Holding (Shenzhen) Co., Limited.; Garuda Technology Co., Ltd. - Applicants: HongQiSheng Precision Electronics (QinHuangdao) Co., Ltd.; Avary Holding (Shenzhen) Co., Ltd.; Garuda Technology Co., Ltd. - Inventors: Cheng-Jia Li - Web page: https://patentgrep.com/patent/US12772374B2 ## CPC - H05K 1/0272: {Adaptations for fluid transport, e.g. channels, holes} - H05K 1/185: associated with components encapsulated in the insulating substrate of the PCBs; associated with components incorporated in internal layers of multilayer circuit boards - H05K 3/22: Secondary treatment of printed circuits {(H05K3/1283 takes precedence; embedding circuits in grooves by pressure H05K3/107)} - H05K 3/4644: {by building the multilayer layer by layer, i.e. build-up multilayer circuits (making via holes in the insulating layers H05K3/0011; special circuit boards as base or core whereon the multilayer is built H05K3/4602)} - H05K 2201/09036: Recesses or grooves in insulating substrate - H05K 2201/10053: Switch - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract A circuit board having a switch includes an insulation material layer, first and second insulation layers, a circular channel, a first cover layer, an inert liquid material, a first conductive block, a second conductive block and a conductive layer. The first and second insulation layers are respectively on bottom and top surfaces of the insulation material layer. The circular channel is in the first and second insulation layers and the insulation material layer, and includes a first sub-channel, a second sub-channel, a first connection channel and a second connection channel. The first cover layer is on a bottom surface of the first insulation layer. The inert liquid material is in the circular channel. The first conductive block is in the first sub-channel. The second conductive block is in the second sub-channel. The conductive layer is in the insulation material layer and adjacent to the circular channel. ## Claims ### Claim 1 A circuit board having a switch, wherein the circuit board comprises: an insulation material layer; a first insulation layer on a bottom surface of the insulation material layer; a second insulation layer on a top surface of the insulation material layer; a circular channel in the first insulation layer, the insulation material layer and the second insulation layer, wherein the circular channel comprises: a first sub-channel extending from the first insulation layer toward the second insulation layer; a second sub-channel adjacent to the first sub-channel and extending from the first insulation layer toward the second insulation layer; a first connection channel fluidly connecting a bottom end of the first sub-channel to a bottom end of the second sub-channel; and a second connection channel fluidly connecting a top end of the first sub-channel to a top end of the second sub-channel; a first cover layer on a bottom surface of the first insulation layer and configured to seal an opening of the first insulation layer; an inert liquid material in the circular channel; a first conductive block in the first sub-channel, wherein a density of the inert liquid material is greater than a density of the first conductive block; a second conductive block in the second sub-channel, wherein a density of the inert liquid material is greater than a density of the second conductive block; and a conductive layer in the insulation material layer and adjacent to the circular channel. ### Claim 2 (depends on 1) The circuit board of claim 1, wherein the first connection channel is fluidly connected to the opening of the first insulation layer. ### Claim 3 (depends on 1) The circuit board of claim 1, further comprising: a second cover layer on a top surface of the second insulation layer. ### Claim 4 (depends on 1) The circuit board of claim 1, wherein the first conductive block is in direct contact with the insulation material layer and the inert liquid material. ### Claim 5 (depends on 1) The circuit board of claim 1, wherein the first conductive block has a conductive block opening, and the conductive block opening extends from a top surface of the first conductive block to a bottom surface of the first conductive block. ### Claim 6 (depends on 1) The circuit board of claim 1, wherein the first conductive block has a same width as a width of the first sub-channel of the circular channel. ### Claim 7 (depends on 1) The circuit board of claim 1, wherein the density of the inert liquid material is between 4.3 g/cm3 and 2.75 g/cm3. ### Claim 8 (depends on 1) The circuit board of claim 1, wherein the density of the first conductive block is between 2 g/cm3 and 2.3 g/cm3. ### Claim 9 A method for fabricating a circuit board having a switch, comprising: forming a first structure, comprising: forming a circular channel in a first insulation layer and an insulation material layer, wherein the first insulation layer is on a top surface of the insulation material layer; disposing a conductive layer in the insulation material layer and adjacent to the circular channel; and disposing a conductive block in the circular channel, wherein the conductive block has a conductive block opening, and the conductive block opening extends from a top surface of the conductive block to a bottom surface of the conductive block; forming a second structure, wherein the second structure has a second insulation layer; bonding the first structure and the second structure to seal the circular channel; forming a first opening in the second insulation layer; injecting an inert liquid material into the circular channel through the first opening, wherein a density of the inert liquid material is greater than a density of the conductive block; and forming a cover layer on a bottom surface of the second insulation layer to seal the first opening of the second insulation layer. ### Claim 10 (depends on 9) The method of claim 9, wherein forming the first structure further comprises: forming a sacrificial layer in the circular channel before or after disposing the conductive block, and the method further comprises: removing the sacrificial layer from the circular channel before injecting the inert liquid material and after forming the first opening. ### Claim 11 (depends on 9) The method of claim 9, wherein forming the circular channel is performed such that the circular channel comprises a first sub-channel and a second sub-channel, and the first and second sub-channels extend in the same direction. ### Claim 12 (depends on 11) The method of claim 11, wherein a width of the second sub-channel is the same as a width of the first sub-channel. ### Claim 13 (depends on 11) The method of claim 11, wherein forming the circular channel is performed such that the circular channel further comprises a first connection channel and a second connection channel, wherein the first connection channel fluidly connects a bottom end of the first sub-channel to a bottom end of the second sub-channel, and the second connection channel fluidly connects a top end of the first sub-channel to a top end of the second sub-channel. ### Claim 14 (depends on 13) The method of claim 13, wherein a length of the first opening is less than a length of the first connection channel. ### Claim 15 (depends on 13) The method of claim 13, wherein a width of the second connection channel is less than a width of the first connection channel.