Chip pre-packaging steel sheet frame packaging structure and manufacturing method thereof
By adopting a chip pre-encapsulated steel sheet frame packaging structure in the chip package, the problems of high wire pad cost and poor I/O wiring flexibility in the prior art are solved, and thinner packaging, lower cost and better performance are achieved.
Patent Information
- Application Number
- CN202411658318.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-20
- Publication Date
- 2025-02-25
AI Technical Summary
In the chip packaging process, the prior art has problems such as high production cost of lead frame wiring pads and poor flexibility in chip I/O arbitrary wiring, and the package thickness is relatively large.
The chip pre-encapsulated steel sheet frame packaging structure is adopted, and the pre-encapsulated chip and flexible I/O wiring are achieved through the combination of stainless steel sheet carrier, peelable material layer, resin layer, chip, pre-encapsulated resin layer, line metal wire and solder resist layer.
The thickness of the chip package is reduced by 30%, the wiring pad production and wiring process is eliminated, the material cost is reduced, the flexibility of I/O arbitrary wiring is improved, and the heat dissipation performance and airtightness of semiconductor electronic components are enhanced.
Smart Images
Figure CN119517853A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of semiconductor chip packaging, in particular to a chip pre-encapsulated steel sheet frame packaging structure and a manufacturing method thereof. Background Art
[0002] At present, the domestic steel sheet peelable frame carrier includes a stainless steel sheet carrier, a peelable material coating and an electrode, wherein the peelable material layer and the electrode are both provided with a plurality, and the number of the peelable material layer is one more than the number of the electrodes; the plurality of peelable material layers and the plurality of electrodes are alternately arranged on the surface of the stainless steel sheet carrier; the thickness of the electrode is greater than the thickness of the peelable material layer, and the lower side of the electrode is in contact with the peelable material layer; in the packaging application process, the invention must first perform solid crystal, wire bonding, glue injection, molding, sheet stripping, cutting, sealing and testing, taping, and packaging processes on the peelable frame carrier, and there are certain limitations in the wiring of the chip to the pins and the arbitrary wiring of I / O. In order to reduce the wire bonding pad production of the lead frame and the wire bonding material cost in the chip packaging process and improve the flexibility of the chip packaging I / O arbitrary wiring, the chip packaging thickness is reduced by 30%, and the "reverse order" process manufacturing method of semiconductor chip packaging can be further adopted to realize multi-chip integrated packaging; therefore, a chip pre-encapsulated steel sheet frame packaging structure and a manufacturing method thereof are proposed. Summary of the invention
[0003] In view of the deficiencies in the prior art, the present invention provides a chip pre-encapsulated steel sheet frame packaging structure and a manufacturing method thereof, which has the advantages of being able to eliminate the wire bonding pad manufacturing of the lead frame and the wire bonding process in the semiconductor chip packaging and reducing material costs. It solves the problem that the existing packaging structure must first undergo die bonding, wire bonding, glue injection, molding, sheet stripping, cutting, sealing and testing, taping, and packaging processes on a removable frame carrier during the packaging application process, and has certain limitations in terms of wiring the chip to the pins and arbitrary I / O wiring.
[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a chip pre-encapsulated steel sheet frame packaging structure and a manufacturing method thereof, comprising a stainless steel sheet carrier, a strippable material layer is fixedly installed on the upper surface of the stainless steel sheet carrier, a resin layer is fixedly installed on the upper surface of the strippable material layer, a chip and a pre-encapsulated resin layer are fixedly installed on the upper surface of the resin layer, a chip bump is fixedly installed on the upper surface of the chip, a circuit metal wire and a solder resist layer are fixedly installed on the upper surface of the pre-encapsulated resin layer, and a welding surface pad is fixedly installed on the surface of the circuit metal wire.
[0005] Furthermore, the pre-encapsulation resin layer is wrapped around the outer surface of the chip, and the chip bumps penetrate the outer surface of the pre-encapsulation resin layer and are fixedly connected to the circuit metal wires.
[0006] Furthermore, the solder resist layer is wrapped around the outer surface of the chip bumps and fixedly connected to the circuit metal wires.
[0007] A method for manufacturing a chip pre-encapsulated steel sheet frame packaging structure comprises the following steps: 1) After the surface of the stainless steel sheet carrier is roughened, a layer of peelable material layer and a resin layer are printed on the surface of the stainless steel sheet carrier.
[0008] 2) After baking, single or multiple chips are glued to the surface of the resin layer in a matrix, with all chip bumps facing upwards, and then the pre-encapsulation resin layer is wrapped around the chip surface using a plastic encapsulation process.
[0009] 3) Then, the pre-encapsulation resin layer is thinned and laser drilling is performed to expose the chip bumps, and then RDL wiring is performed through plasma cleaning, pre-encapsulation resin metallization, circuit pattern transfer, circuit pattern electroplating, film stripping, baking, and flash etching.
[0010] 4) After solder mask layer transfer, solder pad surface treatment, laser cutting, stripping, secondary cutting, sealing and testing, taping and packaging, semiconductor electronic components with chip pre-encapsulated steel sheet frame packaging structure are produced.
[0011] Furthermore, in the step 1), the roll-shaped stainless steel sheet with a thickness of 0.15 mm and a width of 280 mm is roll-to-roll and double-sidedly treated with 180-260 mesh black corundum for surface roughening by dry sandblasting at a speed of 1.5±0.5 m / min and a pressure of 10±2 kg / cm2, and then mechanically cut into PNL size of 280*420 mm, and finally the steel sheet is subjected to secondary wet sandblasting roughening and cleaning and drying treatment by using 15%-25% corundum at a speed of 2.0±0.5 m / min and a pressure of 2.0±0.5 kg / cm2, so that the surface roughness Ra of the steel sheet is controlled at 0.2-0.8 um and the surface of the steel sheet is cleaned.
[0012] Furthermore, in the step 1), a layer of 1-3um thick removable material is printed on the surface of the stainless steel sheet, and then a 10-30um thick resin layer is printed on the surface of the removable material layer using a screen printer under certain parameter conditions and baked at 150 degrees * 60 minutes for curing; the mass percentages of the raw material components of the above-mentioned removable material are: 12%-20% stearic acid, 8%-12% octane, 7%-9% heptane, 7.4%-9% polyvinyl alcohol, 9.2%-10% benzoyl peroxide, 12.2%-13% acetone, 14.2%-15% MDI, 6.6%-7% nanofiller, 10.6%-13% cross-linking agent, 1%-3% additives, and 1%-1.5% amine compounds.
[0013] Furthermore, in the steps 2) and 3), a die bonder is used to adhere a single or multiple chips in a matrix on the surface of the resin layer, with all chip bumps facing upwards, and then a plastic encapsulation process is used to pre-encapsulate the chips with the pre-encapsulation resin material. Subsequently, the pre-encapsulation resin is thinned and laser drilled to expose the chip bumps. Then, RDL wiring is performed through plasma cleaning, pre-encapsulation resin metallization, circuit pattern transfer, circuit pattern electroplating, film stripping, baking, and flash etching, and the minimum line width / line spacing can reach 20um.
[0014] Furthermore, in the step 4), a semiconductor electronic component with a chip pre-encapsulated steel sheet frame packaging structure is produced through solder mask pattern transfer, pad surface treatment, laser cutting and forming, peeling, secondary cutting, sealing and testing, taping, and packaging; the peeling principle is mainly that the release property of the surface of the peelable material layer between the plastic encapsulation glue and the steel sheet bottom electrode enables the entire block product after encapsulation to be effectively peeled off from the stainless steel sheet carrier; the application of peeling requires the use of a vacuum suction cup to suck the entire block product on the back of the plastic encapsulation glue, and then use an automatic peeling mechanism to gently peel off its stainless steel sheet carrier from one side.
[0015] Compared with the prior art, the technical solution of this application has the following beneficial effects: 1. The chip pre-encapsulated steel sheet frame packaging structure and its manufacturing method. The chip pre-encapsulated steel sheet frame packaging structure proposed by the present invention can be arbitrarily designed in layout corresponding to the number of I / Os, thereby improving the flexibility of arbitrary wiring of chip packaging I / Os and reducing the chip packaging thickness by 30%. Further, the "reverse order" process manufacturing method of semiconductor chip packaging can be adopted to realize multi-chip integrated packaging; further, the wire bonding pad manufacturing of the lead frame and the wire bonding process in the semiconductor chip packaging are eliminated, thereby reducing the material cost.
[0016] 2. The chip pre-encapsulation steel sheet frame packaging structure and its manufacturing method use a peelable steel sheet as a carrier, which will not expand or shrink during the chip pre-encapsulation production process, further improving the cutting accuracy and performance of chip packaging products, making semiconductor electronic components have better heat dissipation performance and airtightness, extending their service life, and improving product yield, reducing process flow, reducing production costs in the packaging process, improving cost performance, and facilitating promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a schematic cross-sectional view of the structure of the present invention; Figure 2 It is a schematic diagram of the peeling state of the structural steel sheet of the present invention.
[0018] In the figure: 1. Stainless steel sheet carrier; 2. Strippable material layer; 3. Resin layer; 4. Chip; 5. Pre-encapsulated resin layer; 6. Chip bumps; 7. Circuit metal wires; 8. Solder mask layer; 9. Welding surface pad. DETAILED DESCRIPTION
[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0020] See also Figures 1 to 2 In this embodiment, a chip pre-encapsulated steel sheet frame packaging structure and a manufacturing method thereof include a stainless steel sheet carrier 1, a strippable material layer 2 is fixedly installed on the upper surface of the stainless steel sheet carrier 1, a resin layer 3 is fixedly installed on the upper surface of the strippable material layer 2, a chip 4 and a pre-encapsulated resin layer 5 are fixedly installed on the upper surface of the resin layer 3, a chip bump 6 is fixedly installed on the upper surface of the chip 4, a circuit metal wire 7 and a solder resist layer 8 are fixedly installed on the upper surface of the pre-encapsulated resin layer 5, the pre-encapsulated resin layer 5 is wrapped around the outer surface of the chip 4, the chip bump 6 penetrates through the outer surface of the pre-encapsulated resin layer 5 and is fixedly connected to the circuit metal wire 7, the solder resist layer 8 is wrapped around the outer surface of the chip bump 6 and is fixedly connected to the circuit metal wire 7, and a welding surface pad 9 is fixedly installed on the surface of the circuit metal wire 7.
[0021] A method for manufacturing a chip pre-encapsulated steel sheet frame packaging structure comprises the following steps: 1) After the surface of the stainless steel sheet carrier 1 is roughened, a layer of peelable material layer 2 and a resin layer 3 are printed on the surface of the stainless steel sheet carrier 1; in step 1), a roll of stainless steel sheet with a thickness of 0.15mm and a width of 280mm is roll-to-roll and double-sided with 180-260 mesh black corundum for surface roughening at a speed of 1.5±0.5m / min and a pressure of 10±2kg / cm2, and then mechanically cut into PNL size of 280*420mm, and finally 15%-25% concentration of corundum is used at a speed of 2.0± 0.5m / min, pressure 2.0±0.5kg / cm2 parameters, the steel sheet is subjected to secondary wet sandblasting roughening and cleaning and drying treatment, so that the surface roughness Ra of the steel sheet is controlled at 0.2-0.8um and the surface of the steel sheet is cleaned; in step 1), a layer of 1-3um thick peelable material is printed on the surface of the stainless steel sheet, and then a 10-30um thick resin layer is printed on the surface of the peelable material layer using a screen printer under certain parameter conditions and baked at 150 degrees * 60min for curing; the mass percentage of the raw material components of the above peelable material is: 12%-20% stearic acid, 8%-12% octane, 7%-9% heptane, 7.4%-9% polyvinyl alcohol, 9.2%-10% benzoyl peroxide, 12.2%-13% acetone, 14.2%-15% MDI, 6.6%-7% nanofiller, 10.6%-13% cross-linking agent, 1%-3% additives, 1%-1.5% amine compounds.
[0022] 2) After baking, a single or multiple chips 4 are adhered to the surface of the resin layer 3 in a matrix, with all the chip bumps 6 facing upward, and then the pre-encapsulation resin layer 5 is wrapped on the surface of the chip 4 by a plastic encapsulation process. In step 2), a die bonder is used to adhere a single or multiple chips to the surface of the resin layer in a matrix, with all the chip bumps facing upward, and then the pre-encapsulation resin material is used to pre-encapsulate the chip by a plastic encapsulation process; 3) Then, the pre-encapsulation resin layer 5 is thinned and laser drilled to expose the chip bumps 6, and then plasma cleaning, pre-encapsulation resin metallization, circuit pattern transfer, circuit pattern electroplating, film stripping, baking, and flash etching are performed for RDL wiring. In step 3), the pre-encapsulation resin is thinned and laser drilled to expose the chip bumps, and then plasma cleaning, pre-encapsulation resin metallization, circuit pattern transfer, circuit pattern electroplating, film stripping, baking, and flash etching are performed for RDL wiring. The minimum line width / line spacing can reach 20um.
[0023] 4) Then, the semiconductor electronic components of the chip pre-encapsulated steel sheet frame packaging structure are produced through the transfer of the solder mask pattern 8, the surface treatment of the welding surface pad 9, laser cutting and forming, peeling and stripping, secondary cutting, sealing and testing, taping and packaging. In step 4), the semiconductor electronic components of the chip pre-encapsulated steel sheet frame packaging structure are produced through the transfer of the solder mask pattern, the surface treatment of the welding pad surface, laser cutting and forming, peeling and stripping, secondary cutting, sealing and testing, taping and packaging. The peeling principle is mainly that the release property of the surface layer of the peelable material layer between the plastic encapsulation glue and the bottom electrode of the steel sheet enables the whole block product after encapsulation to be effectively peeled and stripped from the stainless steel sheet carrier. The application of peeling and stripping requires the use of a vacuum suction cup to suck the whole block product on the back of the plastic encapsulation glue, and then use the automatic peeling mechanism to gently peel off its stainless steel sheet carrier from one side.
[0024] In this embodiment, the main chemical components of the stainless steel sheet carrier are C≤0.08, Si≤1.00, Mn≤2.00, P≤0.035, S≤0.030, Ni: 11.00~14.00, Cr: 16.00~19.00, Mo: 1.80~2.50, Ti≥5*C%~0.70, and the density is 7.98g / cm3. The corresponding stainless steel sheet carrier thickness is 0.15mm, and the DFN0603-2L chip pre-encapsulated steel sheet frame packaging structure carrier SET size is 250*70mm, of which each SET has 36400PCS densely packed design, the cutting path spacing is designed to be 0.1mm, and the size of a single PCS is 0.6*0.3mm.
[0025] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.
[0026] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A chip pre-encapsulated steel sheet frame packaging structure, comprising a stainless steel sheet carrier (1), characterized in that: A strippable material layer (2) is fixedly mounted on the upper surface of the stainless steel sheet carrier (1), a resin layer (3) is fixedly mounted on the upper surface of the strippable material layer (2), a chip (4) and a pre-encapsulated resin layer (5) are fixedly mounted on the upper surface of the resin layer (3), a chip bump (6) is fixedly mounted on the upper surface of the chip (4), a circuit metal wire (7) and a solder resist layer (8) are fixedly mounted on the upper surface of the pre-encapsulated resin layer (5), and a soldering surface pad (9) is fixedly mounted on the surface of the circuit metal wire (7).
2. The chip pre-encapsulated steel sheet frame packaging structure according to claim 1, characterized in that: The pre-encapsulation resin layer (5) is wrapped around the outer surface of the chip (4), and the chip bumps (6) penetrate through the outer surface of the pre-encapsulation resin layer (5) and are fixedly connected to the circuit metal wires (7).
3. The chip pre-encapsulated steel sheet frame packaging structure according to claim 1, characterized in that: The solder resist layer (8) is wrapped around the chip bumps (6) and fixedly connected to the outer surface of the circuit metal wires (7).
4. A method for manufacturing a chip pre-encapsulated steel sheet frame packaging structure, characterized in that: The following steps are involved: 1) After the surface of a stainless steel sheet carrier (1) is roughened, a layer of a peelable material layer (2) and a resin layer (3) are printed on the surface of the stainless steel sheet carrier (1). 5.2) After baking, a single or multiple chips (4) are adhered to the surface of the resin layer (3) in a matrix, with all chip bumps (6) facing upwards, and then a pre-encapsulation resin layer (5) is wrapped around the surface of the chip (4) using a plastic encapsulation process. 6.3) The pre-encapsulation resin layer (5) is then thinned and laser drilled to expose the chip bumps (6), and then RDL wiring is performed through plasma cleaning, pre-encapsulation resin metallization, circuit pattern transfer, circuit pattern electroplating, film stripping, baking, and flash etching. 7.4) After the solder mask layer (8) is transferred, the soldering pad (9) is surface treated, laser cutting is performed, the chip is peeled off, secondary cutting is performed, sealing and testing is performed, taping is performed, and packaging is performed to produce a semiconductor electronic component with a chip pre-encapsulated steel sheet frame packaging structure.
8. The method for manufacturing a chip pre-encapsulated steel sheet frame packaging structure according to claim 4, characterized in that: In the step 1), a roll of stainless steel sheet with a thickness of 0.15 mm and a width of 280 mm is subjected to dry sandblasting surface roughening treatment at a speed of 1.5±0.5 m / min and a pressure of 10±2 kg / cm2 on both sides using 180-260 mesh black corundum, and then mechanically cut into PNL size of 280*420 mm, and finally subjected to secondary wet sandblasting roughening and cleaning and drying treatment using 15%-25% concentration corundum at a speed of 2.0±0.5 m / min and a pressure of 2.0±0.5 kg / cm2, so that the surface roughness Ra of the steel sheet is controlled at 0.2-0.8 um and the surface of the steel sheet is cleaned.
9. The method for manufacturing a chip pre-encapsulated steel sheet frame packaging structure according to claim 4, characterized in that: In the step 1), a layer of 1-3um thick strippable material is printed on the surface of the stainless steel sheet, and then a 10-30um thick resin layer is printed on the surface of the strippable material layer using a screen printer under certain parameter conditions and baked at 150 degrees * 60 minutes for curing; the raw material components of the strippable material have the following mass percentages: 12%-20% stearic acid, 8%-12% octane, 7%-9% heptane, 7.4%-9% polyvinyl alcohol, 9.2%-10% benzoyl peroxide, 12.2%-13% acetone, 14.2%-15% MDI, 6.6%-7% nanofiller, 10.6%-13% cross-linking agent, 1%-3% additives, and 1%-1.5% amine compounds.
10. The method for manufacturing a chip pre-encapsulated steel sheet frame packaging structure according to claim 4, characterized in that: In the step 2) and step 3), a die bonder is used to adhere a single or multiple chips in a matrix on the surface of the resin layer, with all chip bumps facing upwards. A plastic encapsulation process is then used to pre-encapsulate the chips with the pre-encapsulation resin material. Subsequently, the pre-encapsulation resin is thinned and laser drilled to expose the chip bumps. RDL wiring is then performed through plasma cleaning, pre-encapsulation resin metallization, circuit pattern transfer, circuit pattern electroplating, film stripping, baking, and flash etching. The minimum line width / line spacing can reach 20um.
11. The method for manufacturing a chip pre-encapsulated steel sheet frame packaging structure according to claim 4, characterized in that: In the step 4), a semiconductor electronic component with a chip pre-encapsulated steel sheet frame packaging structure is manufactured through solder mask pattern transfer, pad surface treatment, laser cutting and forming, peeling, secondary cutting, sealing and testing, taping, and packaging; the peeling principle is mainly that the release property of the surface of the peelable material layer between the plastic encapsulation glue and the steel sheet bottom electrode enables the entire block product after encapsulation to be effectively peeled off from the stainless steel sheet carrier; the application of peeling requires the use of a vacuum suction cup to suck the entire block product on the back of the plastic encapsulation glue, and then use an automatic peeling mechanism to gently peel off its stainless steel sheet carrier from one side.