Improvement of rewiring track structure in die packaging

Abstract

This provides an improvement to the rewiring line structure of die packaging. [Solution] This invention provides an improvement to the redistribution line structure of die packaging, which mainly consists of one die, multiple redistribution lines, and multiple nickel-gold layers. Each redistribution line is formed on the surface of the die by being stretched horizontally using a redistribution layer (RDL) process. Each nickel-gold layer is formed on the surface of each redistribution line by being plated using a chemical nickel-gold (ENIG) process. Each nickel-gold layer consists of a nickel (Ni) layer and a gold (Au) layer, with the gold layer positioned on top of the nickel layer. This structure effectively solves the problems of uneven thickness and process complexity that occur in conventional die packaging when nickel-gold layers are formed using an electroplating process, and the RDL process can improve the design space and reliability of the die packaging.

Description

Technical Field

[0001] The present invention relates to an improvement in the wiring structure in die packaging, and particularly to an improvement in the rewiring line structure of die packaging.

Background Art

[0002] Conventional die packaging includes a die, a plurality of rewiring layers, and a plurality of nickel-gold layers. Each of the rewiring lines is formed on the surface of the die using a formation process for a redistribution layer (RDL). Each of the nickel-gold layers is plated on the surface of each rewiring line using an electroplating process. Each of the nickel-gold layers in conventional die packaging is formed using an electroplating process, which easily results in non-uniform thickness of each nickel-gold layer, and further complicates the manufacturing process. In addition, the electroplating process consumes relatively more energy, is not environmentally friendly, and is not suitable for the green energy orientation of the manufacturing site, so further improvement is needed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The main objective of the present invention is to provide an improved redistribution line structure for die packaging. The structure mainly consists of a die, multiple redistribution lines, and multiple nickel-gold layers. Each redistribution line is formed on the surface of the die by horizontal stretching using a redistribution layer (RDL) process. Each nickel-gold layer is plated using a chemical nickel-gold process and formed on the surface of each redistribution line. Each nickel-gold layer consists of a nickel layer and a gold layer, with the gold layer situated on top of the nickel layer. This structure effectively solves the problems of uneven thickness and process complexity that arise in conventional die packaging where nickel-gold layers are formed using electroplating processes. Furthermore, it effectively improves the design space and reliability of each die pad in the die packaging. [Means for solving the problem]

[0005] To address the above-mentioned objectives, the present invention provides an improvement to the redistribution line structure of die packaging. The die packaging includes one die, multiple redistribution lines, and multiple nickel-gold layers. Multiple die pads are provided on the surface of the die.

[0006] Each of the aforementioned redistribution lines is formed on the surface of the die by being stretched horizontally using a redistribution layer (RDL) process, and each of the redistribution lines has one surface.

[0007] The surface of the die further includes at least one dielectric layer formed using an RDL process, and each dielectric layer has a plurality of recesses formed by being stretched horizontally, each of which is for each die pad of the die to be exposed to the outside.

[0008] Each of the aforementioned rewiring lines is further formed within each recess using a metallic material and electrically connected to each of the die pads.

[0009] Each of the aforementioned nickel-gold layers is provided on the surface of each rewiring line within each recess, and each nickel-gold layer consists of one nickel (Ni) layer and one gold (Au) layer, with the gold layer of each nickel-gold layer situated on top of the nickel layer.

[0010] The die is electrically connected to the outside, in order, via each die pad, each rewiring line, and each nickel gold layer.

[0011] The characteristic feature is that each nickel-gold layer is plated onto the surface of each rewiring line within each recess using a chemical nickel-gold (ENIG, Electroless nickel immersion gold) process.

[0012] The method for manufacturing the die packaging is as follows:

[0013] Step S1: Provide a die packaging. The die packaging has one die, and on the surface of the die there are a plurality of redistribution lines formed by horizontal stretching using an RDL process, each of which is electrically connected to a plurality of die pads on the surface of the die. The method for forming each of the redistribution lines is to first form a dielectric layer on the surface of the die, then form a plurality of recesses by horizontal stretching on each of the dielectric layers, and then form each of the redistribution lines in each of the recesses using a metallic material. Each of the die pads is exposed to the outside from each of the recesses so that each of the redistribution lines is electrically connected to each of the die pads. Each of the redistribution lines has one surface.

[0014] Step S2: Multiple nickel-gold layers are plated onto the surface of each rewiring line within each recess using a chemical nickel-gold (ENIG, Electroless nickel immersion gold) process. Each nickel-gold layer consists of one nickel (Ni) layer and one gold (Au) layer, and the gold layer of each nickel-gold layer is located on top of the nickel layer.

[0015] The present invention provides an improvement to the redistribution line structure of die packaging. The die packaging includes one die, multiple redistribution lines, and multiple nickel-gold layers.

[0016] The die surface has a plurality of die pads.

[0017] Each of the redistribution lines is formed on the surface of the die by being stretched horizontally using an RDL process, and each redistribution line has one surface and two opposing sides.

[0018] Each of the aforementioned rewiring lines is electrically connected to each of the die pads.

[0019] Each of the aforementioned nickel-gold layers is provided on the surface and the two sides of each rewiring line. Each nickel-gold layer consists of one nickel (Ni) layer and one gold (Au) layer, and the gold layer of each nickel-gold layer is located on top of the nickel layer.

[0020] The die is electrically connected to the outside, in order, via each die pad, each rewiring line, and each nickel gold layer.

[0021] The characteristic feature is that each nickel-gold layer is formed by plating on the surface and two sides of each rewiring line using the ENIG process.

[0022] The method for manufacturing the die packaging is as follows:

[0023] Step S1: Provide one die packaging. There is one die on the die packaging, and on the surface of the die, there are a plurality of rewiring lines formed by extending horizontally using the RDL process. Each rewiring line is electrically connected to a plurality of die pads on the surface of the die. The forming method of each rewiring line is as follows: First, form one dielectric layer on the surface of the die, then form a plurality of recesses by extending horizontally on each dielectric layer, and further use a metal material to form each rewiring line in each recess. By exposing each die pad outside each recess, each rewiring line is electrically connected to each die pad. Each rewiring line has one surface.

[0024] Step S2: Remove each dielectric layer around each rewiring line to expose two side surfaces of each rewiring line to the outside.

[0025] Step S3: Use the ENIG process to electroplate a plurality of nickel-gold layers on the surface and the two side surfaces of each rewiring line. Each nickel-gold layer is composed of one nickel (Ni) layer and one gold (Au) layer, and the gold layer of each nickel-gold layer is located on the nickel layer.

[0026] As one of the best embodiments of the present invention, in step S2, further remove all the dielectric layers from the surface of the die.

[0027] As one of the best embodiments of the present invention, each rewiring line is further formed by a metal material of copper (Cu) or aluminum (Al).

[0028] As one of the best embodiments of the present invention, the die further includes one first protection layer, and the side surfaces of each die pad are surrounded by the first protection layer.

[0029] As one of the best embodiments of the present invention, the die further includes one second protection layer, and the second protection layer is installed on the first protection layer. The second protection layer has one opening for each die pad to be exposed to the outside. [Effects of the Invention]

[0030] The structure of the present invention effectively solves the problems of uneven nickel-gold layer thickness and process complexity that arise in conventional die packaging, which uses an electroplating process to form the nickel-gold layer. Furthermore, the RDL process improves the design space and reliability of the die packaging, is advantageous for saving manufacturing costs, and contributes to energy saving and environmental protection. [Brief explanation of the drawing]

[0031] [Figure 1] This is a side cross-sectional view of one embodiment of the die packaging of the present invention. [Figure 2] This is a cross-sectional view in one direction from Figure 1. [Figure 3] This is a side cross-sectional view of a recess formed on the dielectric layer of the present invention. [Figure 4] This is a side cross-sectional view of another embodiment of the die packaging of the present invention. [Figure 5] This is a cross-sectional view in one direction from Figure 4. [Figure 6] This is a side cross-sectional view of a redistribution line formed in a recess on the dielectric layer of the present invention. [Figure 7] This is a diagram showing the dielectric layer in Figure 6 completely removed. [Figure 8] This is a side cross-sectional view of another embodiment of the die packaging of the present invention. [Figure 9] Figure 6 shows the dielectric layer around the rewiring line removed. [Modes for carrying out the invention]

[0032] Embodiments of the present invention will now be described with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and in the description of these embodiments, the descriptions of the same or corresponding parts will be omitted or simplified as appropriate. [Examples]

[0033] Referring to Figures 1, 4, and 8, the present invention provides an improvement to the redistribution line structure of die packaging. The die packaging includes one die 10, a plurality of redistribution lines 20, and a plurality of nickel-gold layers 30. The die 10 has a plurality of die pads 11 on its surface. Each redistribution line 20 is formed on the surface of the die 10 by being stretched horizontally using a redistribution layer (RDL) process and is electrically connected to each die pad 11. Each nickel-gold layer 30 is plated using an electroless nickel immersion gold (ENIG) process and formed on each redistribution line 20. Each nickel-gold layer 30 consists of one nickel (Ni) layer 31 and one gold (Au) layer 32, and as shown in Figures 2 and 5, the gold layer 32 of each nickel-gold layer 30 is located on top of the nickel layer 31. The die 10 is electrically connected to the outside world via each die pad 11, each rewiring line 20, and each nickel-gold layer 30. Each nickel-gold layer 30 formed using the ENIG process is flatter and more uniform than a nickel-gold layer formed using an electroplating process. In the diagrams of this invention, each die pad 11, each rewiring line 20, and each nickel-gold layer 30 are described as merely one example and are not intended to limit the invention.

[0034] Referring to Figures 1, 4, and 8, each of the rewiring lines 20 is further formed from a metallic material of copper (Cu) or aluminum (Al).

[0035] Referring to Figures 1, 4, and 8, the die 10 further includes a first protective layer 12, and each side of the die pad 11 is surrounded by the first protective layer 12.

[0036] Referring to Figures 1, 4, and 8, the die 10 further includes a second protective layer 13, which is installed on top of the first protective layer 12. The second protective layer 13 has an opening 131 to allow each die pad 11 to be exposed to the outside.

[0037] Based on the differences in the formation configuration of each redistribution line 20 and each nickel-gold layer 30 of the die packaging 1 of the present invention, and whether or not a dielectric layer exists on the surface of the die 10, the die packaging 1 of the present invention can be further classified into three embodiments, each of which will be described below.

[0038] The die packaging 1 shown in Figure 1 is a first embodiment of the present invention, and each redistribution line 20 has one surface 23. The surface of the die 10 includes at least one dielectric layer 21 formed using an RDL process, and each dielectric layer 21 has a plurality of recesses 22 formed by being horizontally extended, each recess 22 for each die pad 11 of the die 10 to be exposed to the outside. Each redistribution line 20 is further formed in each recess 22 of a metallic material and is electrically connected to each die pad 11. Each nickel-gold layer 30 is provided on the surface 23 of each redistribution line 20 in each recess 22.

[0039] The manufacturing method of the first embodiment of the die packaging 1 is as follows:

[0040] Step S1: Provide a die packaging 1. Referring to Figure 3, the die packaging 1 has a die 10, and on the surface of the die 10 there are a plurality of redistribution lines 20 formed by horizontal stretching using an RDL process, each of which is electrically connected to a plurality of die pads 11 on the surface of the die 10. The method for forming each of the redistribution lines 20 is to first form a dielectric layer 21 on the surface of the die 10, then form a plurality of recesses 22 by horizontal stretching on each of the dielectric layers 21, and then form each of the redistribution lines 20 in each of the recesses 22 using a metallic material. Each of the die pads 11 is exposed to the outside through each of the recesses 22 so that each of the redistribution lines 20 is electrically connected to each of the die pads 11. Each of the redistribution lines 20 has a surface 23.

[0041] Step S2: As shown in Figure 1, multiple nickel-gold layers 30 are plated onto the surface 23 of each rewiring line 20 within each recess 22 using the ENIG process. Each nickel-gold layer 30 consists of one nickel (Ni) layer 31 and one gold (Au) layer 32, and the gold layer 32 of each nickel-gold layer 30 is located on top of the nickel layer 31, as shown in Figure 2. [Examples]

[0042] Figure 8 shows a second embodiment of the present invention, in which each rewiring line 20 has one surface 23 and two opposing sides 24. Each nickel-gold layer 30 is provided on the surface 23 and the two sides 24 of each rewiring line 20.

[0043] The manufacturing method for the second embodiment of the die packaging 1 is as follows:

[0044] Step S1: Provide a die packaging 1. Referring to Figure 6, the die packaging 1 has a die 10, and on the surface of the die 10 there are a plurality of redistribution lines 20 formed by horizontal stretching using an RDL process, each of which redistribution lines 20 is electrically connected to a plurality of die pads 11 on the surface of the die 10. The method for forming each redistribution line 20 is to first form a dielectric layer 21 on the surface of the die 10, then form a plurality of recesses 22 by horizontal stretching on each of the dielectric layers 21, and then form each of the redistribution lines 20 in each of the recesses 22 using a metallic material. Each of the die pads 11 is exposed to the outside through each of the recesses 22 so that each of the redistribution lines 20 is electrically connected to each of the die pads 11. Each of the redistribution lines 20 has a surface 23.

[0045] Step S2: As shown in Figure 9, the dielectric layer 21 surrounding each rewiring line 20 is removed, thereby exposing two sides 24 of each rewiring line 20 to the outside.

[0046] Step S3: As shown in Figure 8, multiple nickel-gold layers 30 are plated onto the surface 23 and the two sides 24 of each rewiring line 20 using the ENIG process. [Examples]

[0047] Figure 4 shows a third embodiment of the present invention, in which each rewiring line 20 has one surface 23 and two opposing sides 24. Each nickel-gold layer 30 is provided on the surface 23 and the two sides 24 of each rewiring line 20.

[0048] The manufacturing method for the third embodiment of the die packaging 1 is as follows:

[0049] Step S1: Provide a die packaging 1. Referring to Figure 6, the die packaging 1 has a die 10, and on the surface of the die 10 there are a plurality of redistribution lines 20 formed by horizontal stretching using an RDL process, each of which redistribution lines 20 is electrically connected to a plurality of die pads 11 on the surface of the die 10. The method for forming each redistribution line 20 is to first form a dielectric layer 21 on the surface of the die 10, then form a plurality of recesses 22 by horizontal stretching on each of the dielectric layers 21, and then form each of the redistribution lines 20 in each of the recesses 22 using a metallic material. Each of the die pads 11 is exposed to the outside through each of the recesses 22 so that each of the redistribution lines 20 is electrically connected to each of the die pads 11. Each of the redistribution lines 20 has a surface 23.

[0050] Step S2: As shown in Figure 7, the two sides 24 of each rewiring line 20 are exposed to the outside by removing each dielectric layer 21 surrounding each rewiring line 20. Each dielectric layer 21 is further completely removed from the surface 23 of the die 10.

[0051] Step S3: As shown in Figure 8, multiple nickel-gold layers 30 are plated onto the surface 23 and the two sides 24 of each rewiring line 20 using the ENIG process.

[0052] The die packaging 1 of the present invention has the following advantages compared to conventional die packaging.

[0053] (1) Each nickel-gold layer 30 of the present invention is formed by plating on each rewiring line 20 using the ENIG process, thereby effectively solving the problems of uneven thickness of the nickel-gold layer and the complexity of the process that occur when conventional die packaging forms the nickel-gold layer using an electroplating process. This improves product reliability, is advantageous in saving manufacturing costs, and also contributes to energy saving and environmental protection.

[0054] (2) Each of the redistribution lines 20 of the present invention is formed on the surface of the die 10 by being stretched horizontally using an RDL process. Since each of the redistribution lines 20 uses an RDL process that is easy to implement precisely, the process can be simplified, and each of the redistribution lines 20 can simultaneously achieve a certain degree of lightness, thinness, and compactness even in the state of electrical extension and interconnection in the XY plane.

[0055] (3) As shown in Figures 2 and 5, each nickel-gold layer 30 of the present invention is a metal laminated structure having a certain thickness, thereby increasing the structural strength of each rewiring line 20. For example, when the die packaging 1 forms an electrical connection with the outside using wire bonding technology, each nickel-gold layer 30 can withstand the pressure force generated during the wire bonding work or the formation of solder joints, so that each rewiring line 20 is less likely to be damaged by the pressure force. [Explanation of Symbols]

[0056] 1. Die Packaging 10 Dies 11 Die Pad 12 First protective layer 13 Second protective layer 131 Aperture 20 Rewiring line 21 Dielectric layer 22 recesses 23 Surface 24 Side view 30 Nickel gold layer 31 Nickel layer 32 gold layer

Claims

1. It includes one die, multiple rewiring lines and multiple nickel gold layers, The die surface comprises a plurality of die pads, and each of the redistribution lines is a redistribution layer (RDL, Redistribtion A nickel-gold layer is formed on the surface of the die by being stretched horizontally using a Layer process, and each redistribution line has one surface, the surface of the die further includes at least one dielectric layer formed using an RDL process, and on each dielectric layer there are a plurality of recesses formed by being stretched horizontally, each of which is for each die pad of the die to be exposed to the outside, each redistribution line is further formed in each recess of a metallic material and is electrically connected to each die pad, each nickel-gold layer is provided on the surface of each redistribution line in each recess, each nickel-gold layer consists of one nickel (Ni) layer and one gold (Au) layer, the gold layer of each nickel-gold layer is located on top of the nickel layer, and the die is electrically connected to the outside in order via each die pad, each redistribution line and each nickel-gold layer, and its features are, Each nickel-gold layer is plated onto the surface of each rewiring line within each recess using the Electroless nickel immersion gold (ENIG) process. The method for manufacturing the die packaging described above consists of the following steps: Step S1: Provide a die packaging having a die, the die packaging having a plurality of redistribution lines formed on the surface of the die by horizontal stretching using an RDL process, each of the redistribution lines being electrically connected to a plurality of die pads on the surface of the die, the method for forming each of the redistribution lines being first to form a dielectric layer on the surface of the die, then to form a plurality of recesses by horizontal stretching on each of the dielectric layers, and further to form each of the redistribution lines in each of the recesses using a metallic material, and each of the redistribution lines being electrically connected to each of the die pads by exposing each of the die pads to the outside from each of the recesses, each of the redistribution lines having a surface, and Step S2: An improvement to the redistribution line structure of die packaging, characterized in that a plurality of nickel-gold layers are plated onto the surface of each redistribution line within each recess using an ENIG process, each of the nickel-gold layers consists of one nickel (Ni) layer and one gold (Au) layer, and the gold layer of each nickel-gold layer is located on top of the nickel layer.

2. The improved rewiring line structure for die packaging according to claim 1, characterized in that each of the aforementioned rewiring lines is further formed from a metallic material of copper (Cu) or aluminum (Al).

3. The improved rewiring line structure for die packaging according to claim 1, characterized in that the die further includes a first protective layer, and the sides of each die pad are surrounded by the first protective layer.

4. The improved rewiring line structure for die packaging according to claim 3, characterized in that the die further includes a second protective layer, the second protective layer is placed on the first protective layer, and the second protective layer has one opening to allow each die pad to be exposed to the outside.

5. It includes one die, multiple rewiring lines and multiple nickel gold layers, The die has a plurality of die pads on its surface, each redistribution line is formed on the die surface by being stretched horizontally using an RDL process, each redistribution line has one surface and two opposing sides, each redistribution line is electrically connected to each die pad, each nickel-gold layer is provided on the surface and the two sides of each redistribution line, each nickel-gold layer consists of one nickel (Ni) layer and one gold (Au) layer, the gold layer of each nickel-gold layer is located on top of the nickel layer, and the die is electrically connected to the outside in order via each die pad, each redistribution line and each nickel-gold layer, and its features are: Each nickel-gold layer is formed by plating on the surface and two sides of each rewiring line using the ENIG process. The method for manufacturing the die packaging described above consists of the following steps: Step S1: Provide a die packaging having a die on the die packaging, having a plurality of redistribution lines formed on the surface of the die by horizontal stretching using an RDL process, each of the redistribution lines being electrically connected to a plurality of die pads on the surface of the die, the method for forming each of the redistribution lines being first to form a dielectric layer on the surface of the die, then to form a plurality of recesses by horizontal stretching on each of the dielectric layers, and further to form each of the redistribution lines in each of the recesses using a metallic material, and to expose each of the die pads to the outside from each of the recesses so that each of the redistribution lines is electrically connected to each of the die pads, each of the redistribution lines having a surface, Step S2: Remove each dielectric layer surrounding each redistribution line, thereby exposing two sides of each redistribution line to the outside, and Step S3: Using the ENIG process, multiple nickel-gold layers are plated onto the surface and two sides of each rewiring line. An improvement to the rewiring line structure of die packaging, characterized in that each of the nickel-gold layers is composed of one nickel (Ni) layer and one gold (Au) layer, and the gold layer of each nickel-gold layer is located on top of the nickel layer.

6. The improved rewiring line structure for die packaging according to claim 5, further characterized in that, in step S2, each dielectric layer is completely removed from the surface of the die.

7. The improved rewiring line structure for die packaging according to claim 5, characterized in that each of the aforementioned rewiring lines is further formed from a metallic material of copper (Cu) or aluminum (Al).

8. The improved rewiring line structure for die packaging according to claim 5, characterized in that the die further includes a first protective layer, and the sides of each die pad are surrounded by the first protective layer.

9. The improved rewiring line structure for die packaging according to claim 8, characterized in that the die further includes a second protective layer, the second protective layer is installed on the first protective layer, and the second protective layer has one opening to allow each die pad to be exposed to the outside.

Images