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CN-122002687-A - High-heat-dissipation substrate and processing method thereof

CN122002687ACN 122002687 ACN122002687 ACN 122002687ACN-122002687-A

Abstract

The invention discloses a high heat dissipation substrate and a processing method thereof, wherein the operation board is provided with a base layer, a first circuit layer and a second circuit layer which are stacked on the base layer, and the first circuit layer is provided with a lead wire extending to the second circuit layer; the method comprises the steps of covering a photosensitive insulating medium layer on a second circuit layer, making a slot hole on the photosensitive insulating medium layer, enabling a heat dissipation block on the second circuit layer to be completely exposed out of the slot hole, enabling the heat dissipation block to be widened and thickened, enabling gaps to be reserved between the heat dissipation block and the inner wall of the slot hole, depositing a seed layer on the whole plate, filling holes in the gaps to be electroplated, forming copper columns filled in the gaps, obtaining a heat dissipation structure A composed of the copper columns, the widened and thickened heat dissipation block and the seed layer adjacent to the copper columns, electroplating the whole plate to obtain a thickened copper layer, and conducting circuit manufacturing on the thickened copper layer, so that a third circuit layer which is electrically communicated with the second circuit layer through the heat dissipation structure A is obtained. The processing method is reasonable and simple, is easy to operate and implement, and the obtained substrate is high in reliability and good in heat dissipation effect, and meets the high-density packaging requirement.

Inventors

  • ZONG XINRU
  • YANG FEI
  • MA HONGWEI

Assignees

  • 江苏普诺威电子股份有限公司

Dates

Publication Date
20260508
Application Date
20260203

Claims (10)

  1. 1. A processing method of a high-heat-dissipation substrate is characterized by comprising the following processing steps: s1, providing an operation board, wherein the operation board is provided with a base layer (10), a first circuit layer (11) and a second circuit layer (12) which are arranged on the base layer (10) in a stacking way and are electrically communicated, and the first circuit layer (11) is provided with a lead wire extending to the second circuit layer (12); S2, covering a photosensitive insulating medium layer (2) on the second circuit layer (12), and processing a slot hole (20) on the photosensitive insulating medium layer (2) through a photoimaging process, wherein the slot hole (20) can completely expose a heat dissipation block (120) on the second circuit layer (12) and has the functions of conduction and heat dissipation; S3, carrying out whole-plate electroplating through the lead wires so as to widen and thicken the radiating block (120), wherein a gap is reserved between the widened and thickened radiating block and the inner wall of the slotted hole (20); S4, after depositing a seed layer (3) on the whole plate, performing hole filling electroplating on the gap to form a copper column (4) filling the gap, and obtaining a heat dissipation structure A consisting of the copper column (4), the widened and thickened heat dissipation block and the seed layer (3) adjacent to the heat dissipation block and the heat dissipation structure A; s5, carrying out circuit manufacture on the thickened copper layer (5) to obtain a third circuit layer, wherein the third circuit layer is electrically communicated with the second circuit layer (12) through the heat dissipation structure A.
  2. 2. The method for processing a high heat dissipation substrate according to claim 1, wherein the photosensitive insulating medium layer (2) is made of photosensitive polyimide or benzocyclobutene.
  3. 3. The method for processing a high heat dissipation substrate according to claim 1, wherein in the step S2, the working plate is baked and dehumidified by using a nitrogen-filled oven, then the photosensitive insulating medium layer (2) is attached to the second circuit layer (12) by using a vacuum laminator, and then the photosensitive insulating medium layer (2) is sequentially subjected to exposure, development and curing treatment to manufacture the slot hole (20).
  4. 4. The method according to claim 1, wherein in S3, the gap between the widened and thickened heat dissipating block and the inner wall of the slot hole (20) is 60-120 μm, and the height difference between the widened and thickened heat dissipating block and the widened and thickened heat dissipating block is controlled within 7 μm.
  5. 5. The method of manufacturing a high heat dissipating substrate according to claim 1, wherein in S4, the widened and thickened heat dissipating block is subjected to size correction and photoresist removal in order, and then the seed layer (3) is deposited on the whole plate.
  6. 6. The method of manufacturing a high heat dissipating substrate according to claim 5, wherein in S4, the widened and thickened heat dissipating block is subjected to size correction by mechanical polishing so that a height difference between the widened and thickened heat dissipating block and a surface of the photosensitive insulating medium layer (2) is controlled to be within 3 μm; in addition, at least one of PVD process, CVD process and flash plating process is adopted to process the seed layer (3) with the thickness of 2.5-6 mu m.
  7. 7. The method for processing a high heat dissipation substrate according to claim 1, wherein in the step S3, the processing parameters of the whole plate electroplating are that the concentration of monovalent chloride ions in the electroplating solution is 30-50 ppm, the concentration of bivalent copper ions is 10-13 g/L, the concentration of sulfuric acid is 195-220 g/L, the temperature of the electroplating solution is 22-25 ℃, the cathode current density is 5-10 ASD, and the electroplating efficiency is 2-3 μm/min; In the step S4, the processing parameters of the whole plate electroplating are that the monovalent chloride ion concentration in the electroplating solution is 30-50 ppm, the cupric ion concentration is 10-13 g/L, the sulfuric acid concentration is 195-220 g/L, the temperature of the electroplating solution is 22-25 ℃, the cathode current density is not more than 1.2ASD, and the electroplating efficiency is gradually decreased from top to bottom, so that the copper thickness uniformity of the thickened copper layer (5) is controlled within +/-3 mu m.
  8. 8. The method of manufacturing a high heat dissipating substrate according to claim 1, wherein in the step S5, the thickened copper layer (5) is patterned by any one of a subtractive process, an MSAP process and an SAP process.
  9. 9. The method for manufacturing a high heat dissipation substrate according to claim 1, further comprising: S6, determining the property of the third circuit layer, if the third circuit layer is an inner circuit layer, performing the following steps S7-S8, and if the third circuit layer is an outer circuit layer, performing the following step S8; S7, laminating at least one circuit layer A above the third circuit layer, wherein one circuit layer A positioned at the outermost side is an outer circuit layer, the third circuit layer is electrically communicated with the adjacent circuit layers A through a heat dissipation structure B, and/or any two adjacent circuit layers A are electrically communicated through a heat dissipation structure C, and the processing method of the heat dissipation structure B and/or the processing method of the heat dissipation structure C are the same as the processing method of the heat dissipation structure A; and S8, sequentially performing conventional outer layer anti-welding, surface treatment, molding, finished product electrical measurement and finished product inspection processes to obtain the high-heat-dissipation substrate.
  10. 10. A high heat dissipation substrate manufactured by the method for manufacturing a high heat dissipation substrate according to any one of claims 1 to 9.

Description

High-heat-dissipation substrate and processing method thereof Technical Field The invention relates to the technical field of PCB (printed circuit board), in particular to a high-heat-dissipation substrate and a processing method thereof. Background Integrated circuits are increasingly moving toward high integration, high density, high heat dissipation, and low power consumption. For the high heat dissipation function module in the organic substrate, the heat dissipation effect is mainly improved by increasing the volume of copper at present, namely, the heat dissipation effect is realized by arranging a Thermal Bar or a Thermal Square between metal layers. Regarding the manufacturing process of the heat dissipation metal strip/block, the following processing methods are mainly adopted at present: the first processing method is to use Via Post technology (advanced packaging technology combining copper pillar technology and coreless carrier board design) to manufacture large-area heat dissipation metal strips/blocks. However, the Via Post process has the core flow of 'manufacturing a seed layer, covering a dry film, electroplating a pattern, covering the dry film for the second time, electroplating a heat dissipation metal strip/block, removing the film, flashing, laminating and grinding', so that the Via Post process has the problems of incomplete film removal, high CAF failure risk and the like during implementation, and causes great hidden trouble to the quality of a substrate. The second processing mode is to manufacture the heat dissipation metal strip/block by adopting a mode of opening first and then electroplating copper plug after the insulating layer is manufactured. However, the width of the opening is limited by electroplating, so that a large opening cannot be formed, and the electroplated copper layer is recessed due to the large opening, so that the heat dissipation effect of the substrate is limited. In view of this, the present invention has been made. Disclosure of Invention In order to overcome the defects, the invention provides the high-heat-dissipation substrate and the processing method thereof, wherein the processing method is reasonable, the process flow is simple, the operation and implementation are easy, the reliability of the obtained substrate is high, the heat dissipation effect is good, and the high-density packaging requirement is well met. The technical scheme adopted for solving the technical problems is that the processing method of the high-heat-dissipation substrate comprises the following processing steps: S1, providing an operation board, wherein the operation board is provided with a base layer, a first circuit layer and a second circuit layer, wherein the first circuit layer and the second circuit layer are arranged on the base layer in a stacked mode and are electrically communicated, and the first circuit layer is provided with a lead extending to the second circuit layer; S2, covering a photosensitive insulating medium layer on the second circuit layer, and processing a slotted hole on the photosensitive insulating medium layer through a photoimaging process, wherein the slotted hole can completely expose a radiating block on the second circuit layer and has conducting and radiating effects; S3, carrying out whole-plate electroplating through the lead wires so as to widen and thicken the radiating block, wherein a gap is reserved between the widened and thickened radiating block and the inner wall of the slotted hole; S4, after depositing a seed layer on the whole plate, filling holes and electroplating the gaps to form copper columns filling the gaps, and obtaining a heat dissipation structure A consisting of the copper columns, the widened and thickened heat dissipation blocks and the seed layer adjacent to the copper columns and the widened and thickened heat dissipation blocks; S5, manufacturing a circuit on the thickened copper layer to obtain a third circuit layer, wherein the third circuit layer is electrically communicated with the second circuit layer through the heat dissipation structure A. As a further improvement of the invention, the photosensitive insulating medium layer adopts photosensitive polyimide or benzocyclobutene. In the step S2, the working plate is baked and dehumidified by using a nitrogen-filled oven, then the photosensitive insulating medium layer is pasted on the second circuit layer by using a vacuum film pasting machine, and then the photosensitive insulating medium layer is subjected to exposure, development and solidification in sequence, so that the slotted hole is manufactured. In the step S3, the gap between the widened and thickened heat dissipating block and the inner wall of the slot is 60-120 μm, and the height difference between the widened and thickened heat dissipating block and the inner wall of the slot is controlled within 7 μm. As a further improvement of the present invention, in S4, the widened and thickened heat d