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CN-121974707-A - Silicon nitride ceramic chip and preparation method thereof

CN121974707ACN 121974707 ACN121974707 ACN 121974707ACN-121974707-A

Abstract

The invention discloses a silicon nitride ceramic chip and a preparation method thereof, and relates to the technical field of ceramic materials. The method comprises the steps of sequentially adding ceramic powder and sintering aid serving as solid components into a solvent, adding a binder, mixing uniformly, mixing, ball milling to obtain ceramic slurry, coating the ceramic slurry on a film belt, casting and forming, drying to obtain first green sheets and second green sheets with different thicknesses, coating separating agents on two sides of the second green sheets, alternately laminating the second green sheets and the first green sheets, sintering in a nitrogen atmosphere, stripping along a separating agent interface after sintering to obtain the first silicon nitride ceramic sheets and the second silicon nitride ceramic sheets, namely the silicon nitride ceramic sheets with different thicknesses, wherein the thickness of the first green sheets is less than or equal to 0.15mm, and the thickness of the second green sheets is more than or equal to 0.20mm. The silicon nitride ceramic chip prepared by the method has good cutting yield and manufacturing yield, and the ceramic chip has good appearance performance.

Inventors

  • Ge Qia
  • Yan Peitian
  • WANG BIN
  • Cui Mengde
  • DING YINGYING

Assignees

  • 江苏富乐华功率半导体研究院有限公司

Dates

Publication Date
20260505
Application Date
20260311

Claims (10)

  1. 1. The preparation method of the silicon nitride ceramic chip is characterized by comprising the following steps: step 1, sequentially adding ceramic powder and sintering aid serving as solid components into a solvent, adding a binder, uniformly mixing, mixing and ball milling to obtain ceramic slurry; Step 2, coating ceramic slurry on a film belt for tape casting and forming, and drying to obtain a first green sheet and a second green sheet with different thicknesses; step 3, coating a separating agent on the two sides of the second green sheet, and then alternately laminating the second green sheet and the first green sheet, sintering the green sheet in a nitrogen atmosphere, and stripping the sintered green sheet along the interface of the separating agent to obtain a first silicon nitride ceramic sheet and a second silicon nitride ceramic sheet, namely silicon nitride ceramic sheets with different thicknesses; the thickness of the first green sheet is less than or equal to 0.15mm, and the thickness of the second green sheet is more than or equal to 0.20mm.
  2. 2. The method for producing silicon nitride ceramic chips according to claim 1, wherein the first green chips have a thickness of 0.05 to 0.15mm, the second green chips have a thickness of 0.2 to 0.6mm, the number of the first green chips is 8 to 14, the number of the second green chips is 9 to 15, and the thickness of the film tape is 0.05 to 0.15mm.
  3. 3. The method for preparing the silicon nitride ceramic chip according to claim 1, wherein the raw materials of the solid phase component comprise, by weight, 92-94% of ceramic powder and 5-9% of sintering aid; The addition amount of the binder is 5-10wt% of the solid phase component, and the addition amount of the solvent is 40-50wt% of the solid phase component.
  4. 4. The method for producing a silicon nitride ceramic tile according to claim 3, wherein the ceramic powder is one or both of silicon nitride powder and silicon powder, and the sintering aid is one or both of yttrium oxide and magnesium oxide.
  5. 5. The method for producing a silicon nitride ceramic tile according to claim 4, wherein when the ceramic powder is silicon nitride powder, 93-94% by weight of silicon nitride, 3-5% by weight of yttrium oxide, 2-4% by weight of magnesium oxide are contained in the raw materials of the solid phase component; When the ceramic powder is silicon powder, the solid phase component comprises, by weight, 92-93% of silicon powder, 3-5% of yttrium oxide and 2-4% of magnesium oxide.
  6. 6. The method of claim 1, wherein the second green sheet has a double-sided coating separating agent in an amount of 1.0-1.5 mg/cm 2 ; the sintering temperature is 1800-2000 ℃, the sintering time is 4-8 hours, and the sintering pressure is 0.2-0.9 MPa.
  7. 7. The method of manufacturing a silicon nitride ceramic chip according to claim 1, wherein the thickness of the first silicon nitride ceramic chip is 0.08-0.12 mm, and the thickness of the second silicon nitride ceramic chip is 0.25-0.5 mm.
  8. 8. The method for preparing the silicon nitride ceramic chip according to claim 1, wherein the raw materials of the binder comprise, by weight, 8-10 parts of polyvinyl alcohol, 1.5-2.5 parts of n-butyraldehyde, 0.3-0.4 part of yttrium nitrate, 0.1-0.2 part of aluminum nitrate, 0.5-0.8 part of tannic acid and 1-2 parts of lignosulfonate.
  9. 9. The method for preparing the silicon nitride ceramic chip according to claim 8, wherein the preparation method of the binder comprises the following steps of 1, sequentially adding yttrium nitrate, aluminum nitrate and tannic acid into water, setting the temperature to 55-65 ℃, and uniformly stirring to obtain chelating liquid; Step 2, adding polyvinyl alcohol into water, setting the temperature to be 90-95 ℃, stirring, then adding lignosulfonate, and uniformly stirring to obtain a mixed solution; and 3, adding the chelating liquid into the mixed liquid, uniformly stirring, adding n-butyraldehyde, adjusting the pH to 1.5-2.5, stirring at a high speed for 25-45 minutes, setting the temperature to 40-50 ℃, and reacting for 2-4 hours to obtain the binder.
  10. 10. The silicon nitride ceramic chip prepared by the method for preparing the silicon nitride ceramic chip according to any one of claims 1 to 9 is characterized by comprising silicon nitride ceramic chips with different thicknesses.

Description

Silicon nitride ceramic chip and preparation method thereof Technical Field The invention relates to the technical field of ceramic materials, in particular to a silicon nitride ceramic chip and a preparation method thereof. Background Silicon nitride ceramic chips are commonly used for manufacturing silicon nitride substrates, and have irreplaceable application values in the fields of extreme environment and high-precision manufacturing by virtue of excellent comprehensive properties of corrosion resistance, low thermal expansion, high strength and electrical property, wherein the ultra-thin silicon nitride ceramic chips with the thickness of less than or equal to 0.12mm are more key fields and new materials of high-end electronic packaging, power device heat dissipation and the like. However, because the high cost, difficult processing and brittleness risks still limit the market penetration and popularization, how to efficiently obtain the ultrathin silicon nitride ceramic chip, and inhibit cracking, sticking, dishing, breakage and deformation in the manufacturing process of the ultrathin silicon nitride ceramic chip without being influenced by the area, has become a technical problem to be solved urgently in the industry. In the prior art, green bodies with the same specification are mainly adopted for laminating and sintering the ceramic, and the number of sintered lamination is increased or decreased so as to optimize the performance problems encountered in the manufacturing process, but the actual effect is poor. The method has the following defects that firstly, the ultra-thin silicon nitride green sheet is low in strength and poor in toughness, and is easy to damage in the cutting process, secondly, single-thickness green layer is sintered, the edges of the ceramic sheets are easy to overburn and difficult to densify due to uneven temperature in a furnace, thirdly, the green sheets made of the same material are seriously contacted with sintering adhesive sheets directly, and the ceramic sheets with different thicknesses are not shrunk and are not matched, so that the defects of splitting, sinking, deformation and the like are easily caused. In summary, solving the above problems, the present invention provides a silicon nitride ceramic chip and a preparation method thereof. Disclosure of Invention The invention aims to provide a silicon nitride ceramic chip and a preparation method thereof, which are used for solving the problems in the background technology. In order to solve the technical problems, the invention provides the following technical scheme: the preparation method of the silicon nitride ceramic chip comprises the following steps: step 1, sequentially adding ceramic powder and sintering aid serving as solid components into a solvent, adding a binder, uniformly mixing, mixing and ball milling to obtain ceramic slurry; Step 2, coating ceramic slurry on a film belt for tape casting and forming, and drying to obtain a first green sheet and a second green sheet with different thicknesses; step 3, coating a separating agent on the two sides of the second green sheet, and then alternately laminating the second green sheet and the first green sheet, sintering the green sheet in a nitrogen atmosphere, and stripping the sintered green sheet along the interface of the separating agent to obtain a first silicon nitride ceramic sheet and a second silicon nitride ceramic sheet, namely silicon nitride ceramic sheets with different thicknesses; the thickness of the first green sheet is less than or equal to 0.15mm, and the thickness of the second green sheet is more than or equal to 0.20mm. More preferably, the thickness of the first green sheet is 0.05-0.15 mm, the thickness of the second green sheet is 0.2-0.6 mm, the number of the first green sheets is 8-14, and the number of the second green sheets is 9-15 in the alternating lamination; The thickness of the film strip is 0.05-0.15 mm. Wherein the membrane belt is made of PET. More optimally, the raw materials of the solid phase component comprise, by weight, 92-94% of ceramic powder and 5-9% of sintering aid; The addition amount of the binder is 5-10wt% of the solid phase component, and the addition amount of the solvent is 40-50wt% of the solid phase component. Wherein the binder includes, but is not limited to, polyvinyl butyral, and the solvent includes, but is not limited to, ethanol, isopropanol. More preferably, the ceramic powder is one or two of silicon nitride powder and silicon powder, and the sintering aid is one or two of yttrium oxide and magnesium oxide. More optimally, when the ceramic powder is silicon nitride powder, the raw materials of the solid phase component comprise, by weight, 93-94% of silicon nitride, 3-5% of yttrium oxide and 2-4% of magnesium oxide; When the ceramic powder is silicon powder, the solid phase component comprises, by weight, 92-93% of silicon powder, 3-5% of yttrium oxide and 2-4% of magnesium oxide. More o