JP2009158962A - Semiconductor package and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor package excellent in airtightness, moisture resistance and chemical resistance. <P>SOLUTION: The semiconductor package includes: a first substrate at least including a semiconductor base, a functional element provided on one of surfaces of the semiconductor base, a pad electrically connected with the functional element via a first wire, and a through electrode filled with a first conductor via an insulation film A in a fine pore electrically connected with the pad and extending from one of the surfaces of the semiconductor base to the other; and a second substrate bonded with one of the surfaces of the first substrate through the use of a sealant provided around the functional element. The insulation film A is formed to couple with an insulation film B provided on the other surface of the semiconductor base, an insulation film C provided on the external side face of the semiconductor base, and an insulation film D provided on the external side face of the sealant. The exterior of the insulation film is, more preferably, covered doubly with a conductor. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sealing structure of a semiconductor package having a functional element and a through electrode connecting the front and back and a manufacturing method thereof.

Conventionally, for mounting a functional element such as a semiconductor light receiving sensor, a method of storing and sealing inside a sealing container formed of ceramic, resin or the like has been widely used. An example is shown in FIG. 5 (see, for example, Patent Document 1).
A semiconductor package 40 shown in the drawing is composed of a semiconductor substrate 41, a through electrode 45 b, a sealing material 47 and a cap substrate 46. On the semiconductor substrate 41, a light receiving element 44a having a microlens 44b for improving the light collection efficiency is formed and communicates with the outside of the semiconductor package 40 through the wiring 44c and the through electrode 45b.
The light-transmitting protective member 46 such as a glass plate is bonded and fixed on the semiconductor substrate 41 via a sealing material 47 while keeping a gap so as not to touch the light receiving sensor 44a and the micro lens 44b. Further, the sealing material 47 surrounds the light receiving sensor 44a seamlessly, does not cover the light receiving sensor 44a, and is cured after application so that the protective member 46 does not contact the light receiving sensor 44a and the microlens 44b. . As described above, the sealing material 47 fixes the light-transmitting protective member 46 to mechanically protect the light receiving sensor 44a and the micro lens 44b, and also shields the light receiving sensor 44a and the microphone 4 lens 44b from the surrounding atmosphere. It also has a function to do.

JP 2001-351997 A

Such a semiconductor package is manufactured by the following procedure. That is,
First, on the semiconductor substrate 41, a light receiving sensor 44a, a driving circuit for the light receiving sensor 44a (not shown), an output processing circuit, a wiring circuit 44c, and the like are formed by normal semiconductor forming means.
Next, a non-penetrating deep hole is formed in the wiring circuit portion of the semiconductor substrate 41 by anisotropic etching or the like, and a through electrode 45b comprising an insulating layer (not shown) on the inner surface of the deep hole and a conductive layer connected to the wiring circuit portion 44c. To deposit.
Next, the sealing material 47 is applied to one surface of the semiconductor substrate by means of a screen printing method, a dispensing method, or the like so as to surround the individual light receiving sensors 44a without being cut off and to cover them.
Next, a light-transmitting protective member 46 having substantially the same planar dimensions as the semiconductor substrate is pressure-bonded, and the sealing material 47 is cured by applying heat or ultraviolet light to the sealing material 47.
Next, etching is performed until the through electrode 45b formed earlier from the back side of the semiconductor substrate 41 is exposed.
Finally, a large number of semiconductor packages 40 are obtained by dicing to a predetermined size.

A sealing material 47 that joins the semiconductor substrate 41 and the light-transmissive protective member 46 is exposed on the side surface around the semiconductor package thus obtained. Since a synthetic resin is generally used as the sealing material 47, airtightness, moisture resistance, chemical resistance, and the like are not necessarily sufficient depending on the material. Therefore, there is a problem that stable operation and long life of the semiconductor element cannot be obtained.
An object of the present invention is to obtain a semiconductor package structure having high-performance airtightness, moisture resistance, or chemical resistance in order to ensure stable operation and long life of the device.
Another object of the present invention is to provide a manufacturing method for obtaining a semiconductor package structure having such hermeticity, moisture resistance, or chemical resistance without significantly increasing the number of steps. .

In order to solve the above-described problems, one of the semiconductor packages of the present invention includes a semiconductor substrate, a functional element disposed on one surface side of the semiconductor substrate, and an electrical connection to the functional element via a first wiring. And a first conductor is formed through an insulating film A in a fine hole electrically connected to the pad and extending from one surface of the semiconductor substrate to the other surface. A first substrate having at least a through electrode, and a second substrate bonded to one surface of the first substrate using a sealing material disposed around the functional element. In the semiconductor package, the insulating film A includes an insulating film B disposed on the other surface of the semiconductor substrate, an insulating film C disposed on the outer surface of the semiconductor substrate, and an outer surface of the sealing material. A semiconductor package having an insulating film D disposed on the substrate.
With the semiconductor package having such a structure, the sealing material is not exposed on the side surface of the package and is covered with an insulating material having a high shielding effect, so that airtightness, moisture resistance, chemical resistance, etc. are improved. It will be a thing.

Furthermore, the semiconductor package of the present invention includes the insulating film A, the insulating film B disposed on the other surface of the semiconductor substrate, the insulating film C disposed on the outer surface of the semiconductor substrate, and the sealing material. The insulating film D disposed on the outer surface can be integrated.
The surface of the insulating film on the outer surface of the package may be further covered with a conductor.
By integrating each insulating film, there is an advantage that the insulating performance is enhanced. Further, by coating with a conductor, airtightness, moisture resistance, chemical resistance and the like are further improved.

One of the methods for manufacturing a semiconductor package according to the present invention is such that a functional element, a first wiring and a pad are provided on one surface of a semiconductor substrate, and a second substrate is placed inside the second substrate. Bonding using a sealing material, forming a mask having a predetermined pattern on the other surface of the semiconductor substrate, etching the semiconductor substrate through the mask, and Forming a hole reaching the pad at a position corresponding to the pad, forming a groove reaching the sealing material so as to surround the functional element, the first wiring, and the pad; and a seal at a bottom of the groove Etching the stopper to expose the second substrate; forming an insulating film on the inner surface of the hole and groove; etching removing the insulating film formed on the bottom of the hole; Fill the hole with the first conductor Forming a through electrode Te, was manufacturing method comprising a step of cutting along the inner wall of the through-hole reaching the second substrate.
With such a manufacturing method, an insulating layer can also be formed using the through electrode forming process, so that the number of processes is not increased, and a semiconductor package having excellent airtightness, moisture resistance, or chemical resistance is obtained. Obtainable.

According to another method of manufacturing a semiconductor package of the present invention, a functional element, a first wiring, and a pad are provided on one surface of a semiconductor substrate. Bonding using a sealing material, forming a mask having a predetermined pattern on the other surface of the semiconductor substrate, etching the semiconductor substrate through the mask, and Forming a hole reaching the pad at a position corresponding to the pad, forming a groove reaching the sealing material so as to surround the functional element, the first wiring, and the pad; and a seal at a bottom of the groove Etching the stopper to expose the second substrate; forming an insulating film on the inner surface of the hole and groove; etching removing the insulating film formed on the bottom of the hole; The first conductor in the hole Forming a through electrode by filling and filling the groove with a first conductor, and cutting the first conductor formed in the groove reaching the second substrate; It was set as the manufacturing method containing.
Also by this method, the insulating layer and the conductor layer can be formed at the same time by using the through electrode forming process, so that the number of processes is not increased, and the semiconductor package has further excellent airtightness, moisture resistance, or chemical resistance. Can be obtained.

According to the semiconductor package of the present invention, since the side surface of the semiconductor package is covered with a strong insulating film or conductor, excellent airtightness and moisture resistance regardless of the type of sealing material forming the semiconductor package, or A semiconductor package having chemical resistance is obtained, and stable operation and a long life of the package element are ensured.
In addition, according to the method for manufacturing a semiconductor package of the present invention, since an insulating layer and a conductor can be formed using a through electrode forming process, the number of processes is not increased and a semiconductor package with excellent characteristics can be obtained. It is really useful in that it can.

It is sectional drawing of the semiconductor package of the 1st Embodiment of this invention. It is sectional drawing of the semiconductor package of the 2nd Embodiment of this invention. It is sectional process drawing explaining the manufacturing method of the semiconductor package of this invention. FIG. 4 is a sectional process diagram subsequent to FIG. 3; It is sectional drawing of the conventional semiconductor package.

(First embodiment)
FIG. 1 shows a cross-sectional structure of a semiconductor package according to the first embodiment of the present invention. The semiconductor package 1 according to the first embodiment of the present invention has a configuration in which a first substrate 10 on which a functional element 12 is formed and a second substrate 20 forming a cap substrate are bonded using a sealing material 30. Has been.
The first substrate 10 includes a functional element 12 on one surface, a first wiring 13 and a pad 14 connected thereto, and a through electrode 15 that electrically connects the other surface to the pad 14. It consists of a semiconductor substrate 11. The through electrode 15 is configured by filling the inner surface of the fine hole 16 penetrating both the front and back surfaces of the semiconductor substrate 11 with the first conductor 18 through the insulating film A17a.

In this embodiment, the insulating film A17a is formed on the other surface of the semiconductor substrate 11, the insulating film B17b formed on the side surface of the semiconductor substrate 11, and the side surface of the sealing material 30 of the semiconductor package 1. In this example, the insulating film D17d is formed integrally with the insulating film D17d.
The insulating film 17 does not need to be integrally formed. For example, the insulating film A17a, the insulating film C17c, and the insulating film D17d are formed of a nitride film using plasma CVD, and the insulating film B17b is formed of a thermal oxidation method. The oxide film can be formed.
Alternatively, the insulating film A17a, the insulating film 17a, and the insulating film 17 are formed by a method such as forming the whole insulating film 17 integrally with a nitride film or an oxide film using plasma CVD and then over-etching in an insulating film removing process on the bottom surface of the fine hole by RIE or the like. The insulating film B17b can be formed again by using the synthetic resin such as polyamide resin or polyimide resin by removing the insulating film B17b while leaving the film C17c and the insulating film D17d.
That is, the semiconductor package of the present invention only needs to include the insulating film A17a, the insulating film B17b, the insulating film C17c, and the insulating film D17d shown in FIG.
Since the outer periphery of the semiconductor package 1 of the present invention is covered with the insulating film 17 on the side surface and bottom surface of the second substrate 20 except for the surface of the second substrate 20 and the end surface of the through electrode 15, the airtightness, moisture resistance, or chemical resistance is improved. Since it becomes an excellent semiconductor package and the sealing material 30 is also covered with the insulating film 17d, moisture in the atmosphere does not enter from the interface of the joint, and the functional element is completely protected, so the operation is stable, In addition, the service life is significantly increased.

(Second Embodiment)
FIG. 2 shows a cross-sectional structure of a semiconductor package 2 according to the second embodiment of the present invention. The semiconductor package 2 according to the second embodiment of the present invention has the same internal structure as the semiconductor package 1 according to the first embodiment. That is, the first substrate 10 on which the functional element 12 is formed and the second substrate 20 that forms the cap substrate are joined using the sealing material 30, and the first substrate 10 A functional element 12, a first wiring 13 and a pad 14 connected to the functional element 12 are formed on the surface, and the semiconductor substrate 11 includes a penetrating electrode 15 that electrically connects the other surface to the pad 14. The through electrode 15 is configured by filling the inner surface of the fine hole 16 penetrating both the front and back surfaces of the semiconductor substrate 11 with the first conductor 18 through the insulating film A17a. The insulating film A17a includes an insulating film B17b formed on the other surface of the semiconductor substrate 11, an insulating film C17c formed on the side surface of the semiconductor substrate 11, and an insulating film formed on the side surface of the sealing material 30 of the semiconductor package 1. It is formed integrally with the film D17d.
In the semiconductor package 2 according to the second embodiment, the surface of the insulating film C17c formed on the side surface of the semiconductor substrate 11 and the surface of the insulating film D17d formed on the side surface of the sealing material 30 are further provided on the second conductor 19. It is covered with.
Since the side surface of the semiconductor package is doubly covered with the conductor in addition to the insulating film, the sealing function is further strengthened, the functional element is completely protected, the operation is stabilized, and the life is further increased.

Next, an example of a method for manufacturing these semiconductor packages will be described with reference to the drawings.
3 and 4 are cross-sectional process diagrams illustrating a method for manufacturing a semiconductor package of the present invention.
First, a desired functional element 12 such as an optical device and a first wiring 13 and a pad 14 necessary for connection are formed on the surface of a semiconductor substrate 11 such as silicon using a normal semiconductor manufacturing process. The substrate 10 is formed.
As the first wiring 13 and the pad 14, for example, aluminum (Al), copper (Cu), an aluminum-silicon (Al-Si) alloy, an aluminum-silicon-copper (Al-Si-Cu) alloy or the like can be used. Although excellent materials are preferably used, these materials are easily oxidized.

Next, as shown in FIG. 3A, the first substrate 10 on which the functional element 12 is mounted and the second substrate 20 serving as a cap material are bonded using a sealing material 30. At this time, the second substrate 20 is covered and bonded so that the functional element 12 is on the inner side and is not in contact with the functional element 12. The second substrate 20 can also be a semiconductor substrate such as silicon. Examples of the sealing material 30 include photosensitive or non-photosensitive liquid resins (UV curable resins, visible light curable resins, infrared light curable resins, thermosetting resins, etc.) and dry films. As the type of resin, epoxy resin, silicon resin, acrylic resin, polyimide resin, or the like can be used, and may be appropriately selected according to the use environment of the semiconductor package.
In order to form the sealing material 30 layer, for example, a liquid resin is applied to a predetermined position by a printing method, or a dry film is attached and patterned by leaving a predetermined position by a photolithography technique. Available.

Next, as shown in FIG. 3B, a mask 5 is formed on the other surface of the semiconductor substrate 11.
As the mask 5, for example, a UV curable resin, a polyimide-based photosensitive resin, or the like is used, and openings 5 a and 5 b are provided at predetermined positions by photolithography. Here, the opening 5a is for squeezing the fine hole 16 for forming the wiring structure, and is formed as a circular small hole at a position corresponding to the pad 14, for example. On the other hand, the opening 5b is for protecting the functional element 12, and is formed so as to surround the first wiring 13 and the pad 14 with the functional element 12 as the center.

Next, as shown in FIG. 3C, the semiconductor substrate 11 at the positions of the openings 5a and 5b is formed by using, for example, a reactive ion etching (DRIE) method using a mask 5. Etching is performed to form fine holes 16 and grooves 7. By using the DRIE method, it is possible to perform drilling with high accuracy. The DRIE method uses sulfur hexafluoride (SF6) as an etching gas, and alternately etches with high-density plasma and forms a passivation film on the sidewall (Bosch process) to deep-etch the silicon substrate. is there. Although not shown, the groove 7 is formed in a groove shape so as to surround the functional element 12 in plan view. Thereafter, the mask 5 is peeled off if necessary.
The micro holes 16 are not limited to a circle, and may have any size as long as the contact area with the pad 14 can be secured, and the shape may be any shape such as an ellipse, a rectangle, a triangle, and a rectangle.
Further, the method for forming the micro holes 16 is not limited to the DRIE method, and a wet etching method using a potassium hydroxide (KOH) aqueous solution or the like may be used.

Next, as shown in FIG. 3D, the sealing material 30 at the bottom 7a of the groove 7 is removed using means such as dry etching.
Here, if a scribe line is provided in the sealing material 30 in advance, this step can be omitted.

Next, as shown in FIG. 4E, an insulating film 17 is formed on the entire surface of the substrate in the state shown in FIG. As the insulating film 17, silicon oxide (SiO 2), silicon nitride (Si 3 N 4), phosphorus silicate glass (PSG), boron phosphorus silicate glass (BPSG), or the like can be used, and may be appropriately selected according to the use environment of the semiconductor package. . SiO2 and Si3N4 can be formed into arbitrary thicknesses by using CVD. In order to form the insulating film made of SiO2, for example, it can be formed by plasma CVD using silane or tetraethoxysilane (TEOS) as a raw material.
According to this method, the insulating film A17a, the insulating film B17b, the insulating film C17c, and the insulating film D17d shown in FIGS. 1 and 2 can be integrally formed.

Next, as shown in FIG. 4F, the fine hole 16 and the insulating film 17 at the bottom of the groove 7 are removed using dry etching, and the pads 14 and the surfaces 14a and 20a of the second substrate 20 are formed. Expose. However, the insulating film 17 at the bottom of the trench 7 does not necessarily need to be etched away.
In addition, when etching SiO2, a reactive ion etching (RIE) method using carbon tetrafluoride (CF4) can be used.

Next, as shown in FIG. 4G, a first conductor 18 is formed in the microhole 16 using a molten metal suction method or the like. At this time, the conductor 18 may be formed only in the fine hole 16 as shown in FIG. 4G, but as shown in FIG. A method of forming the second conductor 19 can also be employed.
The conductor is not particularly limited as long as it is a good electrical conductor. For example, in addition to copper, aluminum, nickel, chromium, silver, tin, etc. having a low electrical resistance, alloys such as Au—Sn, Sn—Pb, or Sn A metal such as a solder alloy such as a group, Pb group, Au group, In group, or A) group can be used. If a metal is used as the second conductor, if a metal suitable for the usage environment is used, the shielding effect is excellent.

And if it cut | disconnects by the lines L1 and L2 along the inner wall of the groove | channel 7 shown in FIG.4 (g), the semiconductor package 1 of 1st Embodiment shown in FIG. 1 will be obtained.
Since the outer periphery of the semiconductor package 1 is covered with the insulating film 17 on the side surface and the bottom surface of the second substrate 20 except for the end surface of the through electrode 15, a semiconductor having excellent airtightness, moisture resistance, or chemical resistance. Since it becomes a package and the sealing material 30 is also covered with the insulating film 17d, moisture in the atmosphere does not enter from the interface of the joint, and the functional element is completely protected, so that the operation is stable and the life is also long. Markedly longer

Here, as shown in FIG. 4G ′, the second conductor 19 is formed in the groove 7 at the same time as the minute hole 16, and along the center of the second conductor 19 in the groove 7. By cutting along the line L3, the semiconductor package 2 of the second embodiment shown in FIG. 2 is obtained. If the same metal as that of the first conductor 18 is used as the second conductor, it is convenient because it can be formed simultaneously in one process.
In the semiconductor package 2, the surface of the insulating film C 17 c formed on the side surface of the semiconductor substrate 11 and the surface of the insulating film D 17 d formed on the side surface of the sealing material 30 are further covered with the second conductor 19.
Since the side surface of the semiconductor package is double-coated with a metal conductor in addition to the insulating film, the sealing function is further strengthened, the functional element is completely protected, the operation is stabilized, and the lifetime is further increased. .

  The present invention is very useful in that high performance and long life of a semiconductor package are secured.

  1, 2, 40 Semiconductor package, 7 grooves, 10 1st substrate, 11 Semiconductor substrate, 12 Functional element, 13 1st wiring, 14 Pad, 15 Through electrode, 16 Micro hole, 17 Insulating film, 18 1st Conductor, 19 2nd conductor, 20 2nd board | substrate, 30 sealing material.

Claims (5)

  A semiconductor substrate, a functional element disposed on one side of the semiconductor substrate, a pad electrically connected to the functional element via a first wiring, and the pad electrically connected to the pad A first substrate comprising at least a through electrode formed by forming a first conductor through an insulating film A in a fine hole extending from one surface of the semiconductor substrate to the other surface, and the functional element A semiconductor package comprising a second substrate joined to one surface of the first substrate using a sealing material disposed around the substrate, wherein the insulating film A is the other of the semiconductor substrates. An insulating film B disposed on the surface of the semiconductor substrate, an insulating film C disposed on the outer surface of the semiconductor substrate, and an insulating film D disposed on the outer surface of the sealing material. Semiconductor package.   The insulating film A includes an insulating film B disposed on the other surface of the semiconductor substrate, an insulating film C disposed on the outer surface of the semiconductor substrate, and an insulating film disposed on the outer surface of the sealing material. The semiconductor package according to claim 1, wherein the semiconductor package is integrated with D.   The semiconductor package according to claim 1 or 2, wherein the insulating film C and the insulating film D are further covered with a second conductor made of the same member as the first conductor. A step of bonding a second substrate to a first substrate provided with a functional element, a first wiring, and a pad on one surface of a semiconductor substrate using a sealing material so that the functional element is on the inside. And forming a mask having a predetermined pattern on the other surface of the semiconductor substrate, and etching the semiconductor substrate through the mask to form a hole reaching the pad at a position corresponding to the pad And a step of forming a groove reaching the sealing material so as to surround the functional element, the first wiring, and the pad, and the second substrate is exposed by etching away the sealing material at the bottom of the groove A step of forming an insulating film on the inner surfaces of the hole and the groove, a step of etching away the insulating film formed on the bottom of the hole, and filling the hole with the first conductor to penetrate Forming the electrode and the second substrate; The method of manufacturing a semiconductor package which comprises a step of in reaching along the inner wall of the through-hole cutting.   A step of bonding a second substrate to a first substrate provided with a functional element, a first wiring, and a pad on one surface of a semiconductor substrate using a sealing material so that the functional element is on the inside. And forming a mask having a predetermined pattern on the other surface of the semiconductor substrate, and etching the semiconductor substrate through the mask to form a hole reaching the pad at a position corresponding to the pad And a step of forming a groove reaching the sealing material so as to surround the functional element, the first wiring, and the pad, and the second substrate is exposed by etching away the sealing material at the bottom of the groove A step of forming an insulating film on the inner surfaces of the hole and the groove, a step of etching away the insulating film formed on the bottom of the hole, and filling the hole with the first conductor to penetrate At the same time as forming the electrode, in the groove Process and the method of manufacturing a semiconductor package which comprises a step of cutting the first conductor formed on the second groove which reaches to the substrate to fill the first conductor.

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