JP2005045319A - Small electronic component manufacturing method and small electronic component manufactured thereby - Google Patents

Abstract

A method of manufacturing a small electronic component capable of reducing costs without increasing the number of work steps is provided.
A step of repeatedly providing a set of functional elements of an electronic component and an element sealing layer 13 surrounding the functional element on a long functional element substrate 100 at a predetermined interval, and an element sealing layer 13 are formed on the long functional element substrate 100 so that the package substrate sealing layer 23 faces and contacts the element sealing layer 13. The step of placing, the step of melt-bonding the element sealing layer 13 and the package substrate sealing layer 23, and the individual cutting of the functional element substrate 100 from the gap 14 between the adjacent package substrate 200 and package substrate 200 using the cutting fluid 401 And a step of separating.
[Selection] Figure 1

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique for manufacturing electronic components such as a high-frequency filter and a high-frequency switch used in a mobile phone.
[0002]
[Prior art]
The demand for miniaturization of mobile phone components continues, and high frequency filters, high frequency switches, and the like have also been miniaturized by various devices.
[0003]
For example, in a surface acoustic wave (SAW) element that is advantageous for miniaturization as a high-frequency filter, the SAW element chip was previously die-bonded to a small ceramic package and hermetically sealed with a metal cap after bonding, but recently it is small As a packaging method that is advantageous for achieving a reduction in size, a packaging technique capable of further miniaturization has been developed by face-down connection of a SAW element to a packaging substrate, which is disclosed in Patent Document 1 below.
[0004]
FIG. 4 is a diagram for explaining a small electronic component to which the packaging technique is applied and a manufacturing method thereof.
[0005]
First, as shown in FIG. 4A, the functional element electrode 11 is formed on the long functional element substrate material 100a, and the element inner electrode 12 and the element sealing electrode 13 are formed around the functional element electrode 11a. A large number of sets of the functional element electrode 11, the element inner electrode 12, and the element sealing layer 13 are formed along the longitudinal direction of the long functional element substrate material 100a.
[0006]
Then, as shown in FIG. 4 (2), the functional element substrate material 100a corresponding to the aforementioned group is cut and separated by the dicer 400 while spraying the cutting fluid 401 to obtain the functional element chip 101.
4 (3), the package substrate inner electrode 22 is disposed at a position corresponding to the element inner electrode 12 of the functional element chip 101, and the package substrate sealing layer 23 is disposed at a position corresponding to the element sealing layer 13. A package substrate 200 is formed, which is provided on one surface and provided with the package substrate outer electrode 21 electrically connected to the package substrate inner electrode 22 on the other surface.
[0007]
The functional element chip 101 is stacked on the package substrate 200 so that the element inner electrode 12 and the element sealing layer 13 of the functional element chip 101 face the package substrate inner electrode 22 and the package substrate sealing layer 23 of the package substrate 200, respectively. Are melt-bonded.
[0008]
4 (4), a gap 301 is formed between the inner surface (functional surface) of the functional element substrate 100 and the inner surface of the package substrate 200, and the element inner electrode 12 and the package substrate inner electrode. By bonding 22, the signal of the functional element chip 101 is extracted to the outside of the package substrate 200 through the package substrate outer electrode 21.
[0009]
Next, as shown in FIGS. 4 (4) and 4 (5), a predetermined amount of resin liquid 500 a is dropped from above the functional element chip 101, and the resin layer 500 extends from the periphery of the package substrate 200 to the outer surface of the functional element chip 101. And the small electronic component 300 is hermetically sealed.
[0010]
In this conventional small electronic component 300, as can be seen from the sectional view showing the completed state of FIG. 4 (5), the size of the functional element substrate 100 is smaller than the size of the package substrate 200. 4 (2), in which the functional element substrate material 100a is diced to be separated into chips before joining to the substrate.
[0011]
The functional element substrate material 100a is subjected to an electrode treatment for forming the element inner electrode 12 and the element sealing layer 13 before the dicing process. The electrode is usually patterned with aluminum and then metallized with nickel and gold by a lift-off method. Thus, the functional element electrode part 11 is aluminum, and the surfaces of the element inner electrode 12 and the element sealing layer 13 are made of gold.
[0012]
[Patent Literature]
Japanese Patent Laid-Open No. 9-162690
[Problems to be solved by the invention]
By the way, in the conventional manufacturing method, as shown in FIG. 4B, the functional element substrate material 100a is diced in a state where the aluminum of the functional element electrode 11, the gold on the element inner electrode 12, and the element sealing layer 13 coexist. The element substrate 100 is separated.
[0014]
When dicing in the state where different kinds of metals coexist, local batteries are formed between the different kinds of metals by the cutting fluid 401 such as water, and base metals such as aluminum are dissolved. That is, in the process of FIG. 4B, the functional element electrode 11 formed of aluminum is dissolved and corroded.
[0015]
In order to prevent this, a protective coating is applied to the functional element electrode 11, but a protective coating material and a coating process thereof are required, which increases the number of work steps and increases the cost, and the applied protective coating material functions. It has drawbacks such as deteriorating the function of the element.
[0016]
SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a small electronic component that eliminates the drawbacks of the prior art and can reduce costs without increasing the number of work steps, and a small electronic component manufactured thereby.
[0017]
[Means for Solving the Problems]
In order to achieve the above object, the first means of the present invention is to place a set of a functional element of an electronic component and an element sealing layer surrounding the functional element on a long functional element substrate material at a predetermined interval. A long functional device substrate material in which a large number of package substrates formed with a process of repeatedly providing a large number of sets and a package substrate sealing layer facing the device sealing layer are in contact with the device sealing layer facing the device sealing layer A step of placing each with a gap therebetween, a step of melting and bonding the element sealing layer and the package substrate sealing layer, and a functional element substrate material by cutting and separating from the gap between the adjacent package substrate and package substrate using a cutting fluid And a step of performing.
[0018]
According to a second means of the present invention, a functional surface of a functional element substrate having an element sealing layer around and an element inner electrode inside is provided, and a package substrate sealing layer and a package substrate inner electrode are provided at positions facing the functional surface. And the functional element substrate is hermetically sealed by fusion bonding of the element sealing layer and the package substrate sealing layer, and a gap is formed between the functional surface of the functional element substrate and the inner surface of the package substrate. In the method of manufacturing a small electronic component formed with a plurality of sets of the element sealing layer and the element inner electrode on the functional surface of the long functional element substrate material at intervals, and the package on the one surface A large number of package substrates provided with a substrate sealing layer and a package substrate inner electrode are respectively paired on the functional element substrate material. Contacting the element sealing layer, the package substrate sealing layer, the element inner electrode and the package substrate inner electrode, and then the functional element substrate material from the gap between the adjacent package substrate and the package substrate. And a step of cutting and separating while using a cutting fluid.
[0019]
According to a third means of the present invention, in the second means, the element sealing layer and the element inner electrode formed on the functional element substrate material include a base film mainly composed of aluminum or nickel at the portion on the functional element substrate material. Patterning, applying electroless nickel plating and gold plating on the base film,
Forming by forming a film of aluminum from the gold plating to the surface of the functional element substrate, and then patterning the functional element electrode made of aluminum by a dry etching method and removing the aluminum film on the gold plating It is characterized by this.
[0020]
The fourth means of the present invention is a small electronic component manufactured by the first to third means, and the functional element substrate and the package substrate are sealed by fusion bonding of the element sealing layer and the package substrate sealing layer. It is characterized by that.
[0021]
According to a fifth means of the present invention, in the fourth means, the small electronic component is any one of a surface acoustic wave element, a piezoelectric element, and a high frequency switch element.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a manufacturing process diagram of a small electronic component according to the embodiment, FIG. 2 is an explanatory diagram showing a positional relationship between electrodes when a package substrate is placed on a functional element substrate in the manufacturing process, and FIG. It is process drawing which shows formation of the functional element electrode which concerns, an element inner electrode, and an element sealing layer.
[0023]
First, as shown in FIG. 1A, the SAW element manufacturing process according to the embodiment of the present invention has a comb-like functional element on the main surface (functional surface) of the long functional element substrate material 100a. Many sets of the electrode 11, the element inner electrode 12, and the element sealing layer 13 are repeatedly formed along the longitudinal direction of the functional element substrate material 100a.
[0024]
Next, as shown in FIG. 1B, a plurality of package substrates 200 in which a package substrate inner electrode 22 and a package substrate sealing layer 23 are formed at positions facing the element inner electrode 12 and the element sealing layer 13 are formed. One surface (lower surface) is placed at a predetermined position of the functional element substrate material 100a, and the corresponding electrodes of the functional element substrate material 100a and the package substrate 200 are brought into contact with each other.
[0025]
Next, as shown in FIG. 1 (3), in this state, the metallized contact portions are melt-bonded using a hot plate or a reflow furnace, and the functional surface of the functional element substrate material 100 a (the SAW element of the present embodiment). In this case, a void 301 is formed on the surface where the surface acoustic wave is transmitted, and the functional element is hermetically sealed by fusion bonding of the element sealing layer 13 and the package substrate sealing layer 23. In this way, the predetermined gap 14 is formed between the package substrate 200 and the package substrate 200 by individually mounting the package substrate 200 on the long functional element substrate material 100a.
[0026]
Further, by melting and bonding the element inner electrode 12 and the package substrate inner electrode 22, the signal of the functional element can be taken out through the package substrate outer electrode 21 formed on the second surface (outer surface) of the package substrate 200. To do.
[0027]
Next, as shown in FIG. 1 (4), the tip of the dicer 400 is inserted from the gap 14 between the package substrate 200 and the package substrate 200, and the functional element substrate material 100a is moved by the dicer 400 while spraying a cutting fluid 401 such as water. Dicing is performed to form a small SAW filter which is a small electronic component 300 as shown in FIG.
[0028]
In this embodiment, the functional element electrode 11 formed on the cut functional element substrate 100, the element inner electrode 12, the element sealing layer 13, and the package substrate outer electrode 21 formed on the package substrate 200, the package substrate. The inner electrode 22 and the package substrate sealing layer 23 are arranged as shown in FIG. As shown in the figure, the element sealing layer 13 surrounds the functional element electrode 11 and the element inner electrode 12, and the package substrate sealing layer 23 surrounds the package substrate inner electrode 22.
[0029]
The package substrate 200 is usually formed of ceramic, and is wired with vias connecting the first surface (inner surface), the second surface (outer surface) and both surfaces with W-based, Cu-based, and Ag-based conductors. In the case where simple hermetic sealing is sufficient, an organic material such as glass epoxy or polyimide can be used as the insulating material of the package substrate 200.
[0030]
The package substrate outer electrode 21 is usually plated with nickel and gold as metallization for solder connection. The package substrate inner electrode 22 and the package substrate sealing layer 23 are pre-coated with approximately 10 to 50 μm of Au—Sn solder in order to form the air gap 301 at the time of sealing, and the surface of the package substrate 200 as shown in FIG. It protrudes a little more. The solder to be precoated is not limited to Au—Sn, and for example, high melting point solder such as Sn—Sb or Sn—Ag can be used.
[0031]
An embodiment of electrode formation on the functional element substrate material 100a will be described with reference to FIG.
As shown in FIG. 3A, aluminum is deposited by vapor deposition or sputtering at a position on the main surface (functional surface) of the functional element substrate material 100a where the element inner electrode 12 and the element sealing layer 13 are to be formed. The element base aluminum electrode 12a is formed by patterning into a desired shape by a normal photoetching method.
[0032]
Next, as shown in FIG. 3 (2), (1) the surface of the element base aluminum electrode 12a is used as a nucleus and the surface thereof is zincated to form a zincated electrode 12b. (2) Further, using the zincated electrode 12b as a base, a replacement nickel plating electrode 12c and a replacement gold plating electrode 12d are formed electrolessly thereon to form the element inner electrode 12 and the element sealing layer 13.
[0033]
Next, as shown in FIG. 3 (3), aluminum is deposited on almost the entire surface by vapor deposition or sputtering so as to cover the formed element inner electrode 12 and element sealing layer 13, thereby forming a functional element electrode film 11a. To do.
[0034]
Next, as shown in FIG. 3 (4), the functional element electrode film 11a is patterned into a desired comb shape by a normal photoetching method, and at the same time, the aluminum film on the element inner electrode 12 and the element sealing layer 13 is also etched. The element inner electrode 12 and the element sealing layer 13 corresponding to solder connection are exposed.
[0035]
3 (1) and (2), the film formation and patterning of the element base aluminum electrode 12a and the zincate treatment thereof are omitted, and nickel is formed and patterned by a direct sputtering method. The steps up to (2) (2) in FIG. 3 may be performed by plating.
[0036]
In the above-described embodiment, the case of a SAW element has been described. However, the present invention can also be applied to a piezoelectric element such as an FBAR element that requires a gap on the functional element surface, or a high-frequency micro switch (RF-MEMS switch) element.
[0037]
【The invention's effect】
The present invention is configured as described above, and the functional element substrate material and the package substrate are hermetically sealed with a sealing layer before cutting the functional element substrate material. Cutting fluid does not adhere. Accordingly, a protective coating for preventing corrosion is not necessary, and the cost can be reduced without increasing the number of work steps.
[Brief description of the drawings]
FIG. 1 is a manufacturing process diagram of a small electronic component according to an embodiment of the present invention.
FIG. 2 is an explanatory view showing a positional relationship between electrodes when a package substrate is placed on a functional element substrate in the manufacturing process;
FIG. 3 is a process chart of forming a functional element electrode, an element inner electrode, and an element sealing layer according to an embodiment of the present invention.
FIG. 4 is a manufacturing process diagram of a conventionally proposed small electronic component.
[Explanation of symbols]
100: functional element substrate, 100a: functional element substrate material, 101: functional element chip, 11: functional element electrode, 12: element inner electrode, 12a: element base aluminum electrode, 12b: zincated electrode, 12c: substituted Ni plating electrode 12d: replacement Au plating electrode, 13: element sealing layer, 14: gap, 200: package substrate, 21: package substrate outer electrode, 22: package substrate inner electrode, 23: package substrate sealing layer, 300: small electronic component, 301: Gap, 400: Dicer, 401: Cutting fluid.

Claims (5)

On the functional element substrate material, a step of repeatedly providing a large number of sets of functional elements of electronic components and element sealing layers surrounding the functional elements at a predetermined interval;
Placing a large number of package substrates formed with a package substrate sealing layer facing the device sealing layer on the functional device substrate material such that the package substrate sealing layer is in contact with and facing the device sealing layer with a gap; ,
Melting and bonding the element sealing layer and the package substrate sealing layer;
And a step of cutting and separating the functional element substrate material from a gap between adjacent package substrates using a cutting fluid. The functional surface of the functional element substrate having the element sealing layer around and the element inner electrode inside is opposed to the inner surface of the package substrate having the package substrate sealing layer and the package substrate inner electrode facing each other. Contact
In the method of manufacturing a small electronic component in which the functional element substrate is hermetically sealed by fusion bonding of the element sealing layer and the package substrate sealing layer, and a gap is formed between the functional surface of the functional element substrate and the inner surface of the package substrate.
On the functional surface of the functional element substrate material, a step of providing a large number of sets of the element sealing layer and the element inner electrode at an interval;
A plurality of package substrates each provided with a package substrate sealing layer and a package substrate inner electrode on the one surface, each facing each other on the functional element substrate material; and
Melting and bonding the element sealing layer and the package substrate sealing layer and the element inner electrode and the package substrate inner electrode;
And a step of cutting and separating the functional element substrate material from a gap between adjacent package substrates using a cutting fluid. In the manufacturing method of the small electronic component of Claim 2,
The element sealing layer and the element inner electrode formed on the functional element substrate material are:
Patterning a base film mainly composed of aluminum or nickel on the functional element substrate material;
A step of applying electroless nickel plating and gold plating on the base film;
Forming a film of aluminum over the gold plating and on the surface of the functional element substrate;
Then, the functional element electrode made of aluminum is patterned by a dry etching method, and the step of removing the aluminum film on the gold plating is formed. The functional element substrate and the package substrate manufactured by the manufacturing method according to any one of claims 1 to 3 are sealed by fusion bonding of the element sealing layer and the package substrate sealing layer. Small electronic parts to do. 5. The small electronic component according to claim 4, wherein the small electronic component is any one of a surface acoustic wave element, a piezoelectric element, and a high frequency switch element.

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