CN-122028326-A - Method for manufacturing embedded PCB (printed Circuit Board) capable of reducing signal transmission delay and PCB

Abstract

The invention discloses an embedded PCB manufacturing method for reducing signal transmission delay and a PCB, belonging to the technical field of PCB manufacturing, comprising the steps of constructing a plate with an interlayer parallel differential line structure, and respectively arranging each pair of differential lines on different wiring layers; pressing the plates to form a laminate module, and arranging a side wall bonding pad for electric connection on the side wall of the laminate module; an embedding groove matched with the laminate module is formed in the main board, and the laminate module is embedded and fixed in the vertical direction; the invention can reduce signal time sequence deviation caused by serpentine compensation wiring, shorten signal transmission path and improve wiring density and signal transmission stability.

Inventors

• ZHAO SHUAI
• NIE BIN
• YANG ZHIGANG
• WU CHUANBIN

Assignees

• 沪士电子股份有限公司

Dates

Publication Date

20260512

Application Date

20260127

Claims (10)

1. 1. The embedded PCB manufacturing method for reducing signal transmission delay is characterized by comprising the following steps: Constructing a plate with an interlayer parallel differential line structure, wherein each pair of differential lines is arranged on different wiring layers; Laminating the plates with the interlayer parallel differential line structure to form a laminate module, and arranging a side wall bonding pad for electric connection on the side wall of the laminate module; An embedded groove matched with the laminate module is formed in the main board, the laminate module is embedded into the embedded groove in the vertical direction, and the laminate module is fixed by filling a curing medium; after embedding, the signal laminate is electrically connected with the rest layers of the laminate module by manufacturing a pattern circuit and a laser perforation on the signal laminate of the main board.
2. 2. The method for manufacturing an embedded PCB with reduced signal transmission delay according to claim 1, wherein the interlayer parallel wiring mode comprises manufacturing identical pattern lines on both sides of a same core board respectively; the pattern circuit comprises four groups of signal lines and five groups of shielding lines which are alternately arranged in a U shape in sequence.
3. 3. The method of manufacturing an embedded PCB with reduced signal transmission delay according to claim 2, wherein the prepreg and the copper foil are laminated on both sides of the core board, respectively, to form a four-layer board.
4. 4. The method for manufacturing an embedded PCB with reduced signal transmission delay according to claim 3, wherein a shielding hole is further provided on the four-layer board, and the shielding hole is filled with resin.
5. 5. The method for manufacturing an embedded PCB with reduced signal transmission delay according to claim 1, wherein the laminate module is formed by laminating a plurality of four-laminate boards; The side wall of the laminate module is provided with a copper layer.
6. 6. The method of manufacturing an embedded PCB with reduced signal propagation delay of claim 5, wherein the forming of the sidewall pads comprises: and carrying out UV laser treatment on the copper layer to form a bonding pad structure at the leading-out position of the signal line and the shielding line.
7. 7. The method of claim 1, wherein the embedded groove has a groove depth equal to the width of the laminate module and a single-sided gap between the laminate module and the embedded groove is 3mil.
8. 8. The method for manufacturing an embedded PCB with reduced signal transmission delay according to claim 7, wherein the step of embedding the laminate module into the embedded groove in the vertical direction further comprises adhering a high-viscosity high-temperature-resistant adhesive tape to the surface of the main board; the interlayer module is fixed at a position through high-viscosity high-temperature-resistant glue.
9. 9. The method for manufacturing the embedded PCB capable of reducing signal transmission delay according to claim 8, wherein the main board further comprises a power layer board, the high-viscosity high-temperature-resistant adhesive tape is torn off after embedding and curing, the signal layer board and the power layer board are pressed, and the pattern circuit and the laser perforation are manufactured on the signal layer board after pressing.
10. 10. A PCB board manufactured by the method for manufacturing an embedded PCB with reduced signal transmission delay according to any one of claims 1 to 9.

Description

Method for manufacturing embedded PCB (printed Circuit Board) capable of reducing signal transmission delay and PCB Technical Field The invention relates to an embedded PCB manufacturing method for reducing signal transmission delay and a PCB, and belongs to the technical field of PCB manufacturing. Background Along with the rapid development of high-speed computation, artificial intelligent servers, high-speed communication equipment and data center systems, the number of chips and signal channels integrated by a printed circuit board in a unit area is continuously increased, the transmission rate of high-speed signals is continuously improved, higher requirements are put forward on signal integrity, transmission delay consistency and wiring density, and particularly in high-speed serial interfaces and differential signal transmission scenes, the time sequence consistency of signals directly influences the stability of the system. In existing PCB designs, high-speed differential signals are typically arranged in the same wiring layer and transmitted through two signal lines of equal length that are adjacent to each other. Limited by the device pad distribution, BGA fan-out structure, and board space layout, the differential signals inevitably generate turns, fans, and path bypasses during routing. To ensure consistent lengths of the two differential signal lines, designers often need to introduce serpentine compensation traces for length matching. However, the serpentine compensation structure can cause dense bending and pitch variation in local areas of the trace, and impedance discontinuity, parasitic capacitance and parasitic inductance variation are easily introduced, so that problems of reflection, crosstalk and signal distortion are caused. When the signal rate is further increased, the problems are more remarkable and are difficult to be eliminated by simply optimizing line width, line spacing or material parameters. On the other hand, in high density packages, BGA pad areas often have necking routing phenomena, i.e., signal lines are forced to shrink in line width or change wire pitch at pad outlets to accommodate limited fan-out space. This structure also causes abrupt impedance changes and enhanced electromagnetic coupling, further deteriorating the transmission quality of high-speed signals. In a multi-layer PCB structure, as shown in fig. 1 and 2, a common combination of signal layers and ground layers generally employs a stacked structure of "ground layer-signal layer-ground layer" to achieve basic shielding and reference plane control. However, the structure still mainly depends on completing differential wiring in a single layer, when the wiring density is continuously improved, the space resources of the same layer are gradually limited, and the equal length control, the impedance stability and the wiring density requirement are difficult to be simultaneously considered. In addition, in the existing design, the chip and the high-speed connector are generally conducted layer by layer in a horizontal wiring mode, the signal path is longer, the occupied space in the board is larger, and the requirements of high-density interconnection and short-path transmission are difficult to meet. Disclosure of Invention The invention aims to solve the problems that the serpentine compensation wiring and necking wiring structure commonly existing in the high-speed differential signal transmission process of the traditional PCB are easy to cause impedance discontinuity, parasitic parameter change, crosstalk enhancement and signal distortion, and the wiring space of the same layer is limited under the condition of high-density wiring, and the differential wiring is difficult to meet the requirements of equal length control and wiring density. In order to solve the technical problems, the invention is realized by adopting the following technical scheme: The embedded PCB manufacturing method for reducing signal transmission delay comprises the following steps: Constructing a plate with an interlayer parallel differential line structure, wherein each pair of differential lines is arranged on different wiring layers; Laminating the plates with the interlayer parallel differential line structure to form a laminate module, and arranging a side wall bonding pad for electric connection on the side wall of the laminate module; An embedded groove matched with the laminate module is formed in the main board, the laminate module is embedded into the embedded groove in the vertical direction, and the laminate module is fixed by filling a curing medium; after embedding, the signal laminate is electrically connected with the rest layers of the laminate module by manufacturing a pattern circuit and a laser perforation on the signal laminate of the main board. Further, the interlayer parallel wiring mode comprises that the same pattern circuit is respectively manufactured on two sides of the same core plate; the pattern circ