1. Field of the Invention
The present invention relates to an electronic device mounting structure for mounting an electronic device such as a semiconductor chip on a support member such as an interposer, and to a method of mounting the electronic device.
2. Description of the Related Art
With the increasing sophistication of electrical equipment such as mobile phones in recent years, there is a demand for further increases in the speed and performance of electronic devices that are used in the equipment. In order to meet these demands, technical development is required not only to increase the speed of the device itself through miniaturization and the like, but also to increase the speed and density of the package of the device.
As technologies that achieve high-density mounting of electronic devices, research and development of various through-electrode formation technologies and through-wiring substrate formation technologies have been actively advanced. For example, three-dimensional stacking technology that laminates and mounts chips using through wiring and System in Package (SiP) technology that uses a through wiring substrate having through electrodes formed therein have been proposed.
Japanese Unexamined Patent Application, First Publication No. 2005-93954 discloses a substrate having a through electrode that is fabricated from a silicon wafer having an embedded insulating layer between a supporting substrate layer and a silicon layer. In this substrate having a through electrode, a blind via hole is formed reaching the silicon layer to a depth that allows formation of a recess. An inner wall insulating layer is applied onto the blind via hole to form a conductive layer. Then, by removing the silicon layer, the portion of the conductive layer corresponding to the recess is exposed as a wafer outer raised portion.
Japanese Unexamined Patent Application, First Publication No. 2003-282819 discloses a method for manufacturing a semiconductor device that includes: laminating three or more semiconductor chips which each have a terminal with two ends projecting from a substrate, on an interposer; positioning the semiconductor chips and the interposer so as to align the adjacent terminals with each other; and bonding the adjacent terminals together in a lot.
In order to achieve further increases in the speed and density of an apparatus on which an electronic device is mounted, it is necessary to ensure a low-resistance electrical connection between the top of the supporting member, such as an interposer, and the semiconductor chip, or among the laminated semiconductor chips. In order to secure such a low-resistance electrical connection, high positional accuracy between the terminals and reduced resistance of the joined portions between terminals are needed. In conventional mounting technology, in order to prevent position gaps of the opposing terminals between substrates, various position control measures are taken. However, in order to realize a much more high density assembly, it is desired to be able to directly observe the terminal positions on the lower side substrate during the semiconductor chip lamination work.
The present invention was achieved in view of the above circumstances, and has an object of providing an electronic device mounting structure and an electronic device mounting method that make it possible to easily mount an electronic device such as a semiconductor chip on a support member such as an interposer.
In order to solve the aforementioned issues, the present invention employs the following. In particular, an electronic device mounting structure according to a first aspect of the present invention includes: a supporting member that includes a supporting substrate, and a through electrode that penetrates the supporting substrate from a first principal surface that is one principal surface of the supporting substrate to a second principal surface that is the other principal surface, and that includes a projecting portion that projects from the second principal surface; and an electronic device that includes a device substrate on which a circuit is formed, and a through hole that penetrates between both principal surfaces of the device substrate, wherein the electronic device is arranged on the second principal surface of the supporting substrate so that the projecting portion of the supporting member is inserted into the through hole, and the circuit of the electronic device is electrically connected with the projecting portion.
It may be arranged such that the electronic device mounting structure includes a plurality of the electronic devices, wherein each of the electronic devices is laminated on the second principal surface of the supporting substrate.
It may be arranged such that the supporting member includes, on the second principal surface of the supporting substrate, a plurality of device arrangement regions in which the electronic devices are arranged by the projecting portion.
It may be arranged such that the electronic device mounting structure further includes a protective layer that includes the electronic devices within itself.
It may be arranged such that a layer of solder is formed on the outer periphery surface of the projecting portion over the entire length of the projecting portion, and the circuit of the electronic device and the projecting portion are electrically connected by solder that is melted out from the layer of solder.
It may be arranged such that the supporting member includes a connection terminal on the first principal surface side.
An electronic device according to a second aspect of the present invention includes the above-described electronic device mounting structure.
Further, an electronic device mounting method according to a third aspect of the present invention includes: a first step of preparing a supporting member including a supporting substrate, and a through electrode that penetrates the supporting substrate from a first principal surface that is one principal surface of the supporting substrate to a second principal surface that is the other principal surface, and that includes a projecting portion that projects from the second principal surface; a second step of preparing an electronic device that includes a device substrate, and a through hole that penetrates between both principal surfaces of the device substrate; and a third step of arranging the electronic device on the second principal surface of the supporting substrate so that the projecting portion of the supporting member is inserted into the through hole of the electronic device, and electrically connecting the circuit of the electronic device and the projecting portion.
It may be arranged such that the first step includes: a step of laminating, on the second principal surface of the supporting substrate, a projecting portion formation auxiliary layer having a thickness greater than the height of the projecting portion; a step of forming a through hole that penetrates from the first principal surface to the second principal surface of the supporting substrate; a step of forming a communication hole extending from the through hole of the supporting substrate to reach the interior of the projecting portion formation auxiliary layer; a step of filling with a conductor the through hole of the supporting substrate and the communication hole; and a step of exposing the second principal surface of the supporting substrate by removing the projecting portion formation auxiliary layer, and forming a through electrode that consists of the conductor, penetrates the supporting substrate from the first principal surface to the second principal surface, and includes the projecting portion that projects from the second principal surface.
It may be arranged such that the first step includes: a step of forming a hole in a base material that has a thickness greater than the sum of the thickness of the supporting substrate and the height of the projecting portion from a surface that becomes the first principal surface of the supporting substrate; a step of filling the hole with a conductor; and a step of forming the second principal surface of the supporting substrate by removing a portion of the base material from the opposite side of the first principal surface of the base material until a portion of the conductor is exposed, and forming a through electrode that consists of the conductor, penetrates the supporting substrate from the first principal surface to the second principal surface, and includes the projecting portion that projects from the second principal surface.
It may be arranged such that the first step includes a step of foaming a layer of solder on the outer periphery surface of the projecting portion over the entire length of the projecting portion, and the third step includes a step of inserting the projecting portion of the supporting member into each through hole of a plurality of the electronic devices to arrange the electronic devices in a layered manner on the second principal surface of the supporting substrate, and a step of electrically connecting all at once each circuit of the plurality of electronic devices and the projecting portion by melting the layer of solder.
According to the present invention, even after the projecting portion of the support member has been inserted into each through hole of the plurality of electronic devices, it is possible to confirm the position of the projecting portion from above the electronic device. Therefore, high-density mounting of the electronic devices can be easily performed. In addition, since the projecting portion is a unit conductor that is continuous in the lengthwise direction, even if a plurality of electronic devices are mounted in a layered manner, no joining portion will be present between the electronic devices. As a result, it is possible to achieve a lower resistance of the electrical connections among the electronic devices and the reduction of the total thickness of the layered electronic devices.
In
Hereinbelow the preferred embodiments of the present invention shall be described with reference to the drawings.
The supporting member 10 shown in
In the case of the present embodiment, the supporting substrate 11 consists of a semiconductor substrate, such as a silicon (Si) substrate. Insulating layers 111, 112 such as a silicon dioxide film (SiO2) are formed on both principal surfaces 11a and 11b and on the inner wall of a through hole 12, and thereby provide insulation between the circuit 14 and the semiconductor substrate and between the through electrode 13 and the semiconductor substrate. In the case of
The electronic device 6 that is used in the present embodiment is a semiconductor chip that has a device substrate 1, and a through hole 2 that penetrates both principal surfaces 1a, 1b of the device substrate 1. In the case of using a semiconductor chip, the device substrate 1 is a semiconductor substrate such as a silicon (Si) substrate, and it is preferable to provide an insulating layer 3 on the inner wall of the through hole 2 in order to provide insulation between the projecting portion 13a of the through electrode 13 and the semiconductor substrate.
The circuit 4 that constitutes the electronic device is formed on the principal surface 1b of the device substrate 1. It is possible to constitute a portion of the circuit 4 as a semiconductor circuit. The type of electronic device is not particularly limited, and examples include a memory device or sensor device.
A pad 5 that is connected to the circuit 4 is formed at the periphery of the through hole 2. The pad 5 and the projecting portion 13a are electrically connected by an electrically conductive bonding material 7 such as solder or conductive paste.
As shown in
Moreover, electronic circuit components such as resistors, capacitors, and inductors may be provided on the circuit 14 of the supporting member 10. Also, in the case of the supporting substrate 11 consisting of a semiconductor substrate, a semiconductor circuit may be formed on the supporting substrate 11.
According to the electronic device mounting structure of the present embodiment, even after the projecting portion 13a has been inserted into each through hole of the plurality of electronic devices 6, it is possible to confirm the position of the projecting portion 13a from above the electronic devices 6. Therefore, high-density mounting of the electronic devices 6 can be easily performed. Also, since the projecting portion 13a is a unit conductor that is continuous in the lengthwise direction, even if a plurality of electronic devices 6 are mounted in a layered manner, no joining portion will be present between the electronic devices 6. As a result, it is possible to achieve lower resistance of the electrical connections among the electronic devices 6 and reduction of the total thickness of the layered electronic devices 6.
It is possible to manufacture the supporting member 10 of the present embodiment by the manufacturing method shown in
First, as shown in
In the case of the present embodiment, the supporting substrate 11 is a silicon substrate, the projecting portion formation auxiliary layer 16 is a silicon layer, and an embedded insulating layer 112 is provided therebetween. In addition, following the through hole 12, as shown in
It is possible to use an SOI substrate as the Si/SiO2/Si layered product. The dimensions of each layer are not particularly limited, and may be suitably determined in accordance with the intended purpose of the supporting member 10. As a concrete example, the thickness of the supporting substrate 11 is, for example, 150 μm, the thickness of the projecting portion formation auxiliary layer 16 is, for example, 200 μm, the height of the projecting portion 13a is, for example, 180 μm, and the diameter of the through hole 12 (corresponding to the outer diameter of the projecting portion 13a) is, for example, 60 μm.
Methods of forming a hole in Si include a Bosch process that alternately performs Si etching by a high-density plasma using SF6 gas, and passivation film formation on the side wall of the hole using C4F8 gas or the like. It is also possible to employ dry etching techniques other than the Bosch process, wet etching using a chemical solution, and physical processing by a laser or the like.
Methods of forming a hole in SiO2 include dry etching using CF4 gas or the like, wet etching using a chemical solution, and physical processing by a laser or the like.
Next, as shown in
Next, as shown in
Next, as shown in
As the conductor 13, metals such as copper (Cu) and tungsten (W), alloys such as Au—Sn, and nonmetallic conductors such as polysilicon, can be used. As the filling method, it is possible to suitably apply a plating method, a sputtering method, a molten metal filling method, chemical vapor deposition, and the like.
Next, as shown in
When the insulating layer 114 has been formed also in the interior of the communication hole 16a in
When removing the insulating layer 114 from the surface of the projecting portion 13a, in order to protect the insulating layer 112 on the second principal surface 11b, it is preferable to form a protective layer, such as a resist layer, on the insulating layer 112 in advance. Alternatively, it may be arranged such that the thickness of the insulating layer 112 is made thicker beforehand so that the insulating layer 112 with a sufficient thickness remains even if removal of the insulating layer 114 is completed. In this case, the insulating layer 114 on the projecting portion 13a surface can be removed without forming a protective layer, such as a resist layer.
Then, as shown in
In the case of the present embodiment, a supporting substrate 21 consists of an insulating substrate, such as a glass substrate.
In the same manner as the above-mentioned first embodiment, the supporting member 20 has a supporting substrate 21, and a through electrode 23 that penetrates the supporting substrate 21 from a first principal surface 21a to a second principal surface 21b, and has a projecting portion 23a that projects from the second principal surface 21b, with the electronic device 6 mounted on the second principal surface 21b side. In the case of the present embodiment, as shown in
The electronic device 6 is arranged on the second principal surface 21b so that the projecting portion 23a of the supporting member 20 is inserted into a through-hole 2. Moreover, the circuit 4 of the electronic device 6 and the projecting portion 23a are electrically connected. By stacking a plurality of the electronic devices 6 so that the projecting portion 23a is inserted into each through hole 2 of the plurality of electronic devices 6, multi-layering of the electronic devices 6 can be achieved.
Moreover, the supporting member 20 has a connection terminal 25 such as a solder bump on the first principal surface 21a side, and is capable of electrically connecting the circuit 4 of the electronic device 6 and an external substrate (not shown) such as a printed circuit board, via the through electrode 23, the circuit 24 and the and the connection terminal 25.
It is also possible to provide electrical components such as resistors, capacitors, and inductors on the circuit 24 of the supporting member 20.
According to the electronic device mounting structure of the present embodiment, even after the projecting portion 23a has been inserted into each through hole 2 of the plurality of electronic devices 6, it is possible to confirm the position of the projecting portion 23a from above the electronic devices 6. Therefore, high-density mounting of the electronic devices 6 can be easily performed. Moreover, since the projecting portion 23a is a unit conductor that is continuous in the lengthwise direction, even if a plurality of electronic devices 6 are mounted in a layered manner, no joining portion will be present between the electronic devices 6. As a result, it is possible to achieve a reduction in the resistance of the electrical connections among the electronic devices 6 and reduction of the total thickness of the layered electronic devices 6.
Further, according to the present embodiment, since the supporting substrate 21 consists of an insulator, it is not necessary to form an insulating layer on the substrate surface and inner wall of the through hole. As a result, it is possible to simplify the manufacturing process.
The supporting member 20 of the present embodiment can be manufactured by the method shown, for example, in
First, as shown in
The dimensions of each portion are not particularly limited and can be suitably determined according to the application of the supporting member 20. As a concrete example, the thickness of the supporting substrate 21 is, for example, 150 μm, the thickness of the base material 26 is, for example, 500 μm, the depth of the hole 26a is, for example, 320 μm, and the diameter of the hole 26a is, for example, 60 μm.
A method of forming the a fine hole 26a in the glass base material 26 includes a method that modifies the portion of the glass which serves as the hole 26a by femtosecond laser irradiation, and then removes that modified portion by wet etching, as disclosed in Japanese Unexamined Patent Application, First Publication No. 2006-303360. In addition, the hole 26a may also be formed by dry etching that uses gas or the like, wet etching that uses a chemical solution, and physical processing by a laser or the like.
Next, as shown in
As the conductor 23, metals such as copper (Cu) and tungsten (W), alloys such as Au—Sn, and nonmetallic conductors such as polysilicon, can be used. As the filling method, it is possible to suitably apply a plating method, a sputtering method, a molten metal filling method, chemical vapor deposition, and the like.
Then, as shown in
Methods of glass removal include dry etching using gas or the like, and wet etching using a chemical solution such as hydrofluoric acid (HF).
Then, as shown in
In the case of the present embodiment, the through electrode 13A that has the projecting portion 13a consists of a plurality of layers (specifically, two layers consisting of an outer layer 131 and an inner layer 132). Here, the outer layer 131 is constituted from a conductor, and is electrically connected with the circuit 4 of the electronic device 6. In addition, the outer layer 131 and the circuit 14 are formed as a continuous conductor layer. The material of the inner layer 132 may be a conductor or an insulator. Further, the inner layer 132 is included in the outer layer 131 at the distal end of the projecting portion 13a.
The electronic device mounting structure of the present embodiment can exhibit the same function effect as the aforementioned first embodiment.
The supporting member 10A of the present embodiment can be manufactured by the manufacturing method shown, for example, in
In
As the conductor that constitutes the outer layer 131 and the circuit 14, metals such as copper (Cu) and tungsten (W), alloys such as Au—Sn and solder, and nonmetallic conductors such as polysilicon, can be used. As the applying method, it is possible to suitably apply a plating method, a sputtering method, a molten metal filling method, chemical vapor deposition, and the like.
Next, as shown in
Next, as shown in
The supporting member 10A that is obtained by the present embodiment has a structure in which the inner layer 132 is included within the outer layer 131 at the distal end of the projecting portion 13a.
In the case of the present embodiment, the through electrode 13B that has the projecting portion 13a consists of a plurality of layers (specifically, two layers consisting of the outside layer 131 and the inside layer 132). Here, the outer layer 131 is constituted from a conductor, and is electrically connected with the electronic device 6 and the circuit 4. Also, the outer layer 131 and the circuit 14 are formed as a continuous conductor layer. The material of the inner layer 132 may be a conductor or an insulator. Also, the through electrode 13B has a layer structure in which the inner layer 132 is exposed from the outer later 131 at the distal end of the projecting portion 13a.
According to the electronic device mounting structure of the present embodiment, it is possible to exhibit the same function effect of the first and third embodiments described above.
The supporting member 10B of the present embodiment can be manufactured by the manufacturing method shown, for example, in
In
As a concrete example of the dimensions of each portion, the thickness of the supporting substrate 11 is, for example, 150 μm, the thickness of the projecting portion formation auxiliary layer 16 is, for example, 200 μm, the height of the projecting portion 13a is, for example, 180 μm, the outer diameter of the through hole 12 is, for example, 60 μm, and the inner diameter of the through hole 12 (that is, the outer diameter of the core 17) is, for example, 30 μm.
Following the through hole 12, as shown in
The depth of the communication hole 16a in the projecting portion formation auxiliary layer 16 is substantially the same as the height of the projecting portion 13a.
As shown in
Subsequently, as shown in
Then, as shown in
Methods of protecting the insulating layer 111 that is on the outer side of the outer layer 131 include, for example, a method of coating the first principal surface 11a with a protective material such as a resist from the outer side of the through hole 12 to the conductor 131.
As shown in
Subsequently, as shown in
In the supporting member 10B that is obtained by the present embodiment, the through electrode 13B has a layer structure in which the inner layer 132 is exposed at the inner side of the outer layer 131 at the distal end of the projecting portion 13a.
The preferred embodiments of the present invention have hereinabove been described, but the present invention is not limited to the aforementioned embodiments, and various modifications are possible within a scope that does not depart from the gist of the present invention.
The supporting member 10C shown in
The supporting member 10D shown in
In the electronic device mounting structure that uses the supporting member 100 shown in
The electronic device mounting structure shown in
In addition, when performing mounting of the electronic device 6 and formation of the protective layer 8 prior to forming the circuit 14 and the connection terminal 15 on the first principal surface 1a side of the supporting member, it is possible to make the package thinner by grinding the first principal surface 1a side of the supporting substrate 11 and using this protective layer 8 as a support body. In this case, after grinding the first principal surface side 1a, it is possible to provide the circuit 14 and the connection terminal 15 as required.
The dimensions of the through hole 2 and each portion at its periphery are not particularly limited. As a concrete example, the outer diameter of the projecting portion 13a is, for example, 60 μm, the inner diameter of the through hole 2 is, for example, 80 μm, and the I/O pad 5 is a 100 μm square (100 μm□).
First, as shown in
For example, after protecting with a resist the portions other than where the through hole 2 is formed, and then removing the portion of the pad 5 that is exposed from the resist, the exposed portion of the device substrate 1 is removed to penetrate the through hole 2 from the principal surface 1b to the principal surface 1a, whereby it is possible to form the through hole 2 in the device in which the through hole 2 is not formed. The removal of the pad 5 material, in the case of being, for example, Al, is performed by wet etching using a chemical solution. The removal of the device substrate 1, in the case of being, for example, Si, is performed by the aforementioned Bosch process. For the formation of the through hole 2 in the pad 5 and the device substrate 1, it is also possible to employ other types of dry etching, wet etching, and physical processing by a laser or the like.
In the case of performing back surface grinding on the principal surface 1a side of the device substrate 1, back surface grinding is performed after forming a bottomed hole from the principal surface 1b side with a certain amount of depth (a blind via), and so when the hole reaches the principal surface 1a, penetration can be achieved. The depth of the blind via is not particularly limited, but as a concrete example, the depth of the blind via is, for example, 70 μm, and the device substrate 1 is thinned to a thickness of 50 μm by the back surface grinding.
Next, as shown in
Next, as shown in
Next, as shown in
Moreover, by repeating the steps shown in
This supporting member 19 corresponds to one in which the outer layer 131 in the supporting member 10B of the fourth embodiment shown in
Also, in the example shown in
As shown in
According to this method, it is possible to further simplify the mounting step of the electronic devices 6.
Note that in the case of the connecting terminal 15 that is provided on the supporting member 19 being a solder bump, it is possible to form the solder bump 15 after mounting the electronic device 6 by reflowing the layer of solder 18 of the projecting portion 13a. Alternatively, it is possible to simultaneously reflow the layer of solder 18 and the solder bump 15.
The present invention can be suitably utilized for mounting an electronic device on a semiconductor chip.
Number | Date | Country | Kind |
---|---|---|---|
2009-098235 | Apr 2009 | JP | national |
This application is a continuation application based on a PCT Patent Application No. PCT/JP2010/002598, filed Apr. 9, 2010, whose priority is claimed on Japanese Patent Application No. 2009-098035 filed Apr. 14, 2009, the entire content of which are hereby incorporated by reference.
Number | Date | Country | |
---|---|---|---|
Parent | PCT/JP2010/002598 | Apr 2010 | US |
Child | 13271804 | US |