JP2011009781A - Manufacturing method of semiconductor device with through electrode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a semiconductor device with a through electrode with which a penetrating electrode can be formed efficiently for a semiconductor substrate having devices and wirings thereon.SOLUTION: The manufacturing method of the semiconductor substrate with a penetrating electrode includes the steps of forming a first silicon oxide film 12 on both principal surfaces of the semiconductor substrate 11; forming a small hole 13, reaching a first silicon oxide film 12 on the other side principal surface from a principal surface (A); forming a second silicon oxide film 14 on the hole wall of the small hole 13; forming a first and second thin metal films 15 and 16 on the first silicon oxide film 12; removing the first silicon oxide film 12 on an end of the small hole 13; and forming a through-hole electrode 17 by filling conductive substance in the small hole 13. The small hole 13 is formed by a DRIE method. The conductive substance is filled in the small hole 13 by a molten metal suction method or a printing method.

Description

  The present invention relates to a method of manufacturing a semiconductor device with a through electrode used for wiring such as an electronic device or an optical device, or a wiring layer when stacking devices.

A semiconductor substrate with a through electrode may be used for wiring of various devices such as electronic devices and optical devices, and a wiring layer when the devices are stacked.
FIG. 7 is a schematic cross-sectional view showing an example of the configuration of a semiconductor substrate with a through electrode provided with a through electrode.
The semiconductor substrate with a through electrode includes a semiconductor substrate 1 made of a silicon substrate, the insulating layer 2 formed on the surface of the semiconductor substrate 1 and the pore walls of the pores 4 penetrating the semiconductor substrate 1, and the pores 4. It is generally composed of a through electrode 3 made of a conductive material layer such as a filled metal.

Next, an example of a method for manufacturing a semiconductor substrate with a through electrode will be described with reference to FIG.
In order to manufacture a semiconductor substrate with a through electrode, first, as shown in FIG. 8A, a pore forming step for forming a pore 4 penetrating the semiconductor substrate 1 is performed on the semiconductor substrate 1.
Examples of the method for forming the pores 4 include a DRIE (Deep-Reactive Ion Etching) method represented by ICP-RIE (Inductively Coupled Plasma-Reactive Ion Etching), an anisotropic etching method using a potassium hydroxide solution, and the like. Examples include a machining method using a micro drill and a photoexcited electrolytic polishing method.
Next, as shown in FIG. 8B, an insulating layer forming step for forming the insulating layer 2 on the surface of the semiconductor substrate 1 and the hole walls of the pores 4 is performed.
Next, as shown in FIG. 8C, a through electrode 3 is formed by filling the pores 4 with a conductive substance such as metal by a molten metal suction method, a sputtering method, a plating method, a printing method, or the like. A semiconductor substrate with a through electrode is obtained.

 The semiconductor substrate with through electrodes obtained in this way is used as a substrate for manufacturing various devices, or, as shown in FIG. It can be used as a base (interposer) for stacking and wiring devices.

As described above, in the conventional method for manufacturing a semiconductor substrate with a through electrode, various devices and wirings are manufactured after the through electrode is formed on the semiconductor substrate. Therefore, depending on the physical properties of the conductive material forming the through electrode, the subsequent heat treatment temperature is restricted, and as a result, devices and wirings that can be manufactured are limited.
For example, when the wiring is formed of aluminum, a heat treatment of about 400 ° C. called a sintering process may be performed, but the through electrode is formed of a eutectic metal such as gold tin (Au—Sn) or a conductive paste. In such a case, the heat treatment may cause melting of the metal or changes in physical properties of the conductive paste.

Moreover, when manufacturing an electronic device in the semiconductor substrate with a penetration electrode mentioned above, there exists a problem shown below from the surface of a manufacturing process.
Usually, in a clean room where an electronic device is manufactured, metal other than standard metals such as aluminum is avoided as much as possible from the viewpoint of heavy metal contamination. A manufacturing process for manufacturing a device or wiring on a semiconductor substrate with a through electrode uses a plurality of facilities such as a film forming apparatus and a patterning apparatus, which is not desirable from the viewpoint of preventing contamination. If a semiconductor substrate or device with a through electrode is contaminated, the characteristics may deteriorate not only in the substrate but also in other electronic devices that do not have the through electrode due to contamination through the equipment (cross contamination). . Therefore, when the through electrode is applied to an electronic device, it is desirable that the formation of the through electrode is concentrated in the final process as much as possible.

  In addition, since the surface of the through electrode usually has irregularities of about several μm, the irregularities may affect the production process depending on the device to be produced. For example, when a resist is applied to a semiconductor substrate with a through electrode using a spin coater, if the surface of the through electrode is uneven, it is difficult to apply a uniform resist in the vicinity thereof.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a method for manufacturing a semiconductor device with a through electrode that efficiently forms a through electrode with respect to a semiconductor substrate on which devices and wirings are already formed. To do.

 A method for manufacturing a semiconductor device with a through electrode according to the present invention is a method for manufacturing a semiconductor device with a through electrode in which main surfaces of a semiconductor substrate on which a device is formed in advance are wired, and at least the device of the semiconductor substrate is formed. A first insulating layer forming step of forming a first insulating layer on one of the main surfaces, and a thin film forming step of forming a metal thin film on the first insulating layer following the first insulating layer forming step Forming a pore that reaches the first insulating layer directly below the metal thin film from the other main surface of the semiconductor substrate without exposing the metal thin film, following the step and the thin film forming step And, following the pore formation step, forming a second insulating layer on the pore wall of the pore, the back surface of the first insulating layer in the pore and the other main surface of the semiconductor substrate, Reactive Ion The metal that forms the metal thin film when the metal thin film is exposed to the pores by removing the second insulating layer at the end of the pores and the first insulating layer by etching. The second insulating layer forming step for preventing the metal from directly adhering to the pore wall surface of the pores, and the second insulating layer forming step, and then, at the end of the pores. Following the insulating layer removing step, the second insulating layer and the first insulating layer are removed by a reactive ion etching method to expose the metal thin film in the pores. And a conductive substance filling step of filling the pores with a conductive substance.

In the insulating layer removing step, it is preferable that the second insulating layer and the first insulating layer at the end of the pores are continuously removed by a reactive ion etching method.
In the second insulating layer forming step, the second insulating layer is preferably formed by a plasma CVD method or a sputtering method.

  The pores are preferably formed by a deep-reactive ion etching method.

  The metal thin film is preferably formed by laminating two or more layers of different kinds of metals.

  As described above, according to the present invention, since a through electrode can be efficiently formed on a semiconductor substrate on which an electronic device and wiring are already provided, a semiconductor device with a through electrode is easily manufactured. be able to.

It is sectional drawing which showed one Embodiment of the manufacturing method of the semiconductor substrate with a penetration electrode of this invention in order of a process, and cut | disconnected the semiconductor substrate in the extending direction of the penetration electrode. It is the top view which looked at the semiconductor substrate with a penetration electrode from the semiconductor substrate upper surface. It is a schematic sectional drawing which shows an example of a structure of the semiconductor substrate with a penetration electrode obtained by the manufacturing method of the semiconductor substrate with a penetration electrode of this invention. It is sectional drawing which showed one Embodiment of the manufacturing method of the semiconductor device with a penetration electrode of this invention in order of a process, and cut | disconnected the semiconductor device in the extension direction of the penetration electrode. It is the top view which looked at the semiconductor device with a penetration electrode from the semiconductor substrate upper surface. It is a schematic sectional drawing which shows an example of a structure of the semiconductor device with a penetration electrode obtained by the manufacturing method of the semiconductor device with a penetration electrode of this invention. It is a schematic sectional drawing which shows an example of a structure of the semiconductor substrate with a penetration electrode provided with the penetration electrode. It is a figure explaining an example of the manufacturing method of the conventional semiconductor substrate with a penetration electrode. It is a schematic sectional drawing which shows the other example of a structure of the semiconductor substrate with a penetration electrode provided with the penetration electrode.

The present invention will be described in detail below.
An embodiment of a method for producing a semiconductor substrate with a through electrode according to the present invention will be described with reference to FIGS.
In this embodiment, a method for manufacturing a semiconductor substrate with a through electrode used as a base (interposer) or the like when stacking electronic devices will be described.
FIG. 1 shows a method of manufacturing a semiconductor substrate with a through electrode according to this embodiment in the order of steps, and is a cross-sectional view of the semiconductor substrate cut in the extending direction of the through electrode. FIG. It is the top view seen from the board | substrate upper surface.

In the semiconductor substrate with through electrodes of this embodiment, first, as shown in FIG. 1A, insulating layers having a thickness of about 1 μm are formed on both main surfaces of a semiconductor substrate 11 made of a silicon substrate having a thickness of about 300 μm. First silicon oxide film 12 is formed (first insulating layer forming step). In this embodiment, for example, the first silicon oxide film 12 is formed by a thermal oxidation method at a temperature of 1000 ° C. for 4 hours.
Note that the method of forming the first silicon oxide film 12 is not limited to the thermal oxidation method, and it is also formed by a plasma CVD method, a sputtering method, or the like depending on the thickness of the silicon oxide film and a desired application. can do.

In this embodiment, by using a silicon substrate as the semiconductor substrate 11, an insulating layer made of the first silicon oxide film 12 can be easily formed by thermal oxidation or the like. In addition, when a silicon substrate is used, pores described later can be accurately formed in the surface of the semiconductor substrate 11 by a deep-reactive ion etching (hereinafter, abbreviated as “DRIE”) method described later. .
Further, by forming the first silicon oxide film 12, the metal thin film formed in the subsequent process and the semiconductor substrate 11 are insulated. Therefore, by forming the metal thin film into a desired shape, the metal thin film can be used as a wiring between the electronic device provided on the semiconductor substrate 11 and the through electrode. Or when using a semiconductor substrate with a penetration electrode as a base at the time of carrying out lamination wiring of an electronic device, this metal thin film can be used also as a wiring layer.
Furthermore, by using the first silicon oxide film 12 as an insulating layer, the first silicon oxide film 12 functions as an etching stop layer when forming pores by the DRIE method. The pores can be formed uniformly. Then, only the first silicon oxide film 12 can be removed by changing the etching gas. In this case, since the metal thin film described later functions as an etching stop layer, desired pores can be formed immediately below the metal thin film in a series of steps.

Next, as shown in FIG. 1B, the first silicon oxide film 12 is removed from the portion on one main surface A where the through electrode is to be formed.
Next, as shown in FIG. 1C, a thin-film extending from one main surface A to the first silicon oxide film 12 formed on the other main surface side is formed on the semiconductor substrate 11 by Deep-Reactive Ion Etching. The hole 13 is formed (pore formation process). Here, the Deep-Reactive Ion Etching method uses sulfur hexafluoride (SF ₆ ) or the like as an etching gas, and alternately performs etching with high-density plasma and passivation film formation on the sidewalls of the pores 13. (Bosch process), which is a method of deeply etching the semiconductor substrate 11.
Note that the shape of the cross section perpendicular to the depth direction of the pores 13 may be any shape such as a circle, an ellipse, a triangle, a quadrangle, and a rectangle, and the size is also the size of a desired semiconductor substrate with a through electrode. It is appropriately set according to conductivity (resistance value) and the like.

  Thus, if the fine pores 13 are formed by the DRIE method, fine processing of the fine pores 13 is easy, and the semiconductor substrate to be used and the etching gas are appropriately selected, so that the fine pores 13 and the later-described fine pores 13 can be formed. Since the removal of the first silicon oxide film 12 directly under the metal thin film can be performed by a series of processes, the desired pores 13 can be efficiently formed.

Next, as shown in FIG. 1D, a second silicon oxide film 14 which is an insulating layer having a thickness of about 1 μm is formed on the hole wall of the pore 13 (second insulating layer forming step). In this embodiment, for example, the second silicon oxide film 14 is formed by a thermal oxidation method at a temperature of 1000 ° C. for 4 hours.
Note that the method of forming the second silicon oxide film 14 is not limited to the thermal oxidation method, and it is also formed by a plasma CVD method, a sputtering method, or the like depending on the thickness of the silicon oxide film and a desired application. can do.
In this way, by forming the second insulating layer on the hole wall of the pore 13, the conductive material filled in the pore 13 and the semiconductor substrate 11 are insulated in the subsequent step.

Next, as shown in FIG. 1E, a first metal thin film 15 and a second metal thin film 16 made of a material different from the first metal thin film 15 are formed on at least the first silicon oxide film 12 on the pores 13. Form (thin film forming step). In this embodiment, the first metal thin film 15 and the second metal thin film 16 are formed by sputtering, for example.
If necessary, these metal thin films are patterned by an appropriate method so that the electrode pad 22 on the through electrode portion 21 as shown in FIG. 2A or the substrate 20 as shown in FIG. Other electrode pads 23 and wirings 24 for connecting them can be formed. In this embodiment, for example, an aluminum-silicon (Al—Si) thin film is formed as the first metal thin film 15, and an aluminum (Al) thin film is formed as the second metal thin film 16.
In this embodiment, an aluminum-silicon thin film is formed as the first metal thin film 15 and an aluminum thin film is formed as the second metal thin film 16, but the present invention is not limited to this. The first metal thin film 15 is made of gold, platinum, titanium, silver, copper, bismuth, tin according to the type of conductive material filled in the pores 13 in order to improve the adhesion with the through electrode 17. , Nickel, chromium, zinc and other metals, and alloys thereof, and the like can be formed in combination. Further, the second metal thin film 16 is made of gold, platinum, titanium, or the like depending on the type of solder bumps or circuit patterns (wirings) provided on other semiconductor substrates. It is selected from metals such as silver, copper, bismuth, tin, nickel, chromium, zinc, and alloys thereof, and can be formed in combination. In this embodiment, the metal thin film formed on the semiconductor substrate 11 is composed of two layers of the first metal thin film 15 and the second metal thin film 16, but the present invention is limited to this. The metal thin film may be formed by laminating three or more layers of different types of metals.

  As described above, if the metal thin film formed on the semiconductor substrate 11 is formed by laminating two or more layers of different kinds of metals, the adhesion between the conductive material filled in the pores 13 and the metal thin film. Therefore, highly reliable electrical connection can be realized between the through electrode 17 and the metal thin film (here, the first metal thin film 15 and the second metal thin film 16).

Next, as shown in FIG. 1 (f), only the first silicon oxide film 12 at the end of the pore 13 on the side where the first metal thin film 15 and the second metal thin film 16 are formed is etched. It removes by a process and the 1st metal thin film 15 is exposed in the pore 13 (insulating layer removal process). In this embodiment, for example, carbon tetrafluoride (CF ₄ ) is used as an etching gas, and the first silicon oxide film 12 is etched by a dry etching method using a RIE (Reactive Ion Etching) method.

Next, as shown in FIG. 1 (g), the conductive material is filled into the pores 13 by the molten metal suction method or the printing method, and the through electrode 17 is formed (conductive material filling step), with the through electrode. A semiconductor substrate is obtained.
In the conductive material filling step, the first metal thin film 15 and the second metal thin film 16 are electrically connected to the through electrode 17 by filling the pores 13 with the conductive material.

Here, the molten metal suction method is performed by immersing a semiconductor substrate in a molten metal bath in a reduced pressure environment such as in a vacuum chamber and then increasing the pressure (for example, reducing the degree of vacuum or setting it to atmospheric pressure). In this method, molten metal is filled in the pores. In this molten metal suction method, for example, a eutectic metal composed of gold (Au) 80 wt% -tin (Sn) 20 wt% is used as the conductive material. If the conductive material is filled into the pores 13 using the molten metal suction method, the fine pores 13 can be efficiently filled with the conductive material. In addition, since the conductive material can be filled up to the end portion in the pore 13, the first metal thin film 15 and the second metal thin film 16 and the through electrode 17 formed by the conductive material are electrically connected. Are connected to each other, and the through electrode 17 functions as an electrode.
In this embodiment, eutectic metal composed of 80% by weight of gold and 20% by weight of tin is filled as the conductive material in the pores 13 by the molten metal suction method, but the present invention is limited to this. It is not a thing. As the conductive material, it is possible to use gold-tin alloys having different compositions, metals such as tin and indium, or solders such as tin-lead, tin group, lead group, gold group, indium group, and aluminum group. it can.

In the printing method, for example, a copper (Cu) paste is filled in the pores 13 by a stencil printing method. If a conductive material is filled in the pores 13 using a printing method, even if the area of the main surface of the semiconductor substrate 11 or the laminated body of the semiconductor substrates 11 is increased, the pores 13 are uniformly and efficiently filled. A conductive substance can be filled. In addition, since the conductive material can be filled up to the end portion in the pore 13, the first metal thin film 15 and the second metal thin film 16 and the through electrode 17 formed by the conductive material are electrically connected. Are connected to each other, and the through electrode 17 functions as an electrode.
Although the pores 13 are filled with copper paste as a conductive material by a printing method, the present invention is not limited to this. As the conductive substance, a conductive paste such as a silver paste, a carbon paste, or a gold-tin paste can be used.

  On one main surface A of the semiconductor substrate with a through electrode obtained in this embodiment, an electrode pad 25 and a wiring 26 as shown in FIG. 3 (a), or FIG. Metal bumps 27 as shown in FIG.

  In addition, since the semiconductor substrate with a through electrode obtained in this embodiment can be electrically connected to the front and back by the through electrode 17, it can be used as a base (interposer) when stacking and wiring electronic devices, Can be used as a wiring layer when electrically connecting.

Next, an embodiment of a method for manufacturing a semiconductor device with a through electrode according to the present invention will be described with reference to FIGS.
In this embodiment, a semiconductor device with a through electrode that efficiently forms a through electrode with respect to a semiconductor substrate already provided with a general-purpose IC such as a MEMS (Micro Electro Mechanical Systems) drive or control or a MEMS device such as a sensor is provided. A manufacturing method will be described.
FIG. 4 shows the method of manufacturing the semiconductor device with a through electrode of this embodiment in the order of steps, and is a cross-sectional view of the semiconductor device cut in the extending direction of the through electrode. FIG. It is the top view seen from the board | substrate upper surface.

In the method for manufacturing a semiconductor device with a through electrode of this embodiment, first, as shown in FIG. 4A, at least a through electrode is formed on the surface of the semiconductor substrate 30 on which the electronic device 31 is provided. A first silicon oxide film 32, which is an insulating layer having a thickness of about 1 μm, is formed at a location (first insulating layer forming step). In this embodiment, for example, the first silicon oxide film 32 is formed by a plasma CVD method using tetraethoxysilane (TEOS) as a raw material.
The method for forming the first silicon oxide film 32 is not limited to the plasma CVD method using TEOS as a raw material, and silane gas (SiH ₄ ) or the like can be used as a raw material. In consideration of the damage to the electronic device 31, a sputtering method, a thermal oxidation method, or the like can be applied.

In this embodiment, by using a silicon substrate as the semiconductor substrate 30, an insulating layer made of the first silicon oxide film 32 can be easily formed by plasma CVD or the like. In addition, if a silicon substrate is used, pores described later can be formed with high accuracy in the plane of the semiconductor substrate 30 by the DRIE method.
Further, by forming the first silicon oxide film 32, the metal thin film formed in the subsequent process and the semiconductor substrate 30 are insulated. Therefore, by forming the metal thin film in a desired shape, the metal thin film can be used as a wiring between the electronic device provided on the semiconductor substrate 30 and the through electrode.
Further, by using the first silicon oxide film 32 as an insulating layer, the first silicon oxide film 32 functions as an etching stop layer when forming pores by the DRIE method. The pores can be formed uniformly. Then, only the first silicon oxide film 32 can be removed by changing the etching gas. In this case, since the metal thin film described later functions as an etching stop layer, desired pores can be formed immediately below the metal thin film in a series of steps.

4B, a first metal thin film 33 and a second metal thin film 34 made of a different material are formed on at least the first silicon oxide film 32 (thin film formation). Process). In this embodiment, the first metal thin film 33 and the second metal thin film 34 are formed by sputtering, for example.
By patterning these metal thin films as necessary, an electrode pad 38 as shown in FIG. 5A and a wiring 39 with the electronic device 31 can be formed. In this embodiment, an aluminum-silicon thin film is formed as the first metal thin film 33, and an aluminum thin film is formed as the second metal thin film 34.
Further, the electrode pad 38 and the wiring 39 are formed simultaneously.
In this embodiment, an aluminum-silicon thin film is formed as the first metal thin film 33 and an aluminum thin film is formed as the second metal thin film 34. However, the present invention is not limited to this. The first metal thin film 33 is made of gold, platinum, titanium, silver, copper, bismuth, tin according to the type of conductive material filled in the pores 35 in order to improve the adhesion with the through electrode 37. , Nickel, chromium, zinc and other metals, and alloys thereof, and the like can be formed in combination. In addition, the second metal thin film 34 is formed on another semiconductor substrate in order to improve adhesion with solder bumps, circuit patterns (wirings), etc., depending on these types, gold, platinum, titanium, It is selected from metals such as silver, copper, bismuth, tin, nickel, chromium, zinc, and alloys thereof, and can be formed in combination. In this embodiment, the metal thin film formed on the semiconductor substrate 30 is composed of two layers of the first metal thin film 33 and the second metal thin film 34, but the present invention is limited to this. The metal thin film may be formed by laminating three or more layers of different types of metals.

Thus, if the metal thin film formed on the semiconductor substrate 30 is formed by laminating two or more layers of different types of metals, the adhesion between the conductive material filled in the pores described later and the metal thin film Therefore, a highly reliable electrical connection can be realized between the through electrode and the metal thin film (here, the first metal thin film 33 and the second metal thin film 34).
In addition, when the structure of FIG. 4B has already been realized by normal IC manufacturing, the present embodiment can be started from the process described in FIG. 4C.

Next, as shown in FIG. 4C and FIG. 5B, at a position overlapping the electrode pad 38 on the main surface B opposite to the surface on which the electronic device 31 and the electrode pad 38 are formed, by the DRIE method. Then, pores 35 extending from the main surface B to the first silicon oxide film 32 are formed in the semiconductor substrate 30 (pore formation step).
The shape of the cross section perpendicular to the depth direction of the pores 35 may be any shape such as a circle, an ellipse, a triangle, a quadrangle, and a rectangle, and the size is also the size of a desired semiconductor substrate with a through electrode. It is appropriately set according to conductivity (resistance value) and the like.

  Thus, if the formation of the pores 35 is performed by the DRIE method, the fine processing of the pores 35 is easy, and the pores 35 and the later-described ones can be selected by appropriately selecting the semiconductor substrate and the etching gas to be used. Since the removal of the second silicon oxide film directly below the first metal thin film 33 and the second metal thin film 34 can be performed by a series of processes, the desired pores 35 can be efficiently formed.

Next, as shown in FIG. 4D, a second silicon oxide film 36 which is an insulating layer having a thickness of about 1 μm is formed on the hole wall of the pore 35 and the other main surface B of the semiconductor substrate 30 (see FIG. 4D). Second insulating layer forming step). In this embodiment, for example, the second silicon oxide film 36 is formed by plasma CVD using tetraethoxysilane (TEOS) as a raw material.
The method for forming the second silicon oxide film 36 is not limited to the plasma CVD method using TEOS as a raw material, and silane gas (SiH ₄ ) or the like can be used as a raw material. In consideration of the damage to the electronic device 31, a sputtering method, a thermal oxidation method, or the like can be applied.

Next, as shown in FIG. 4E, the second silicon oxide film 36 and the first first end of the pore 35 on the side where the first metal thin film 33 and the second metal thin film 34 are formed. Only the silicon oxide film 32 is removed by an etching process to expose the first metal thin film 33 in the pores 35 (insulating layer removing step). In order to remove only the silicon oxide film at the end of the pore 35, the silicon oxide film on the surface of the semiconductor substrate 30 may be protected with a resist or the like, and an anisotropic etching process may be applied. In this embodiment, for example, carbon tetrafluoride (CF ₄ ) is used as an etching gas, and the first silicon oxide film 32 and the second silicon oxide film 36 are formed by dry etching using RIE (Reactive Ion Etching). Etching is performed.

Next, as shown in FIG. 4 (f), the conductive material is filled into the pores 35 by the molten metal suction method or the printing method, and the through electrode 37 is formed (conductive material filling step), with the through electrode. Obtain a semiconductor device.
In the conductive material filling step, the first metal thin film 33 and the second metal thin film 34 are electrically connected to the through electrode 37 by filling the pores 35 with the conductive material.

In the molten metal suction method, for example, a eutectic metal composed of 80% by weight of gold and 20% by weight of tin is used as the conductive material. On the other hand, in the printing method, for example, the copper paste is filled in the pores 35 by a stencil printing method. If the conductive material is filled in the pores 35 using the molten metal suction method, the fine pores 35 can be efficiently filled with the conductive material. Further, since the conductive material can be filled up to the end portion in the pore 35, the first metal thin film 33 and the second metal thin film 34 and the through electrode 37 formed by this conductive material are electrically connected. And the through electrode 37 functions as an electrode.
In this embodiment, eutectic metal composed of 80% by weight of gold and 20% by weight of tin is filled in the pores 35 as a conductive substance by the molten metal suction method, but the present invention is limited to this. It is not a thing. As the conductive material, it is possible to use gold-tin alloys having different compositions, metals such as tin and indium, or solders such as tin-lead, tin group, lead group, gold group, indium group, and aluminum group. it can.

In the printing method, for example, the copper (Cu) paste is filled in the pores 35 by a stencil printing method. If the conductive material is filled in the pores 35 by using the printing method, even if the area of the main surface of the semiconductor substrate 30 or the stacked body of the semiconductor substrates 30 is increased, the pores 35 are uniformly and efficiently filled. A conductive substance can be filled. Further, since the conductive material can be filled up to the end portion in the pore 35, the first metal thin film 33 and the second metal thin film 34 and the through electrode 37 formed by this conductive material are electrically connected. And the through electrode 37 functions as an electrode.
In addition, although the copper paste was filled into the pores 35 as a conductive material by a printing method, the present invention is not limited to this. As the conductive substance, a conductive paste such as a silver paste, a carbon paste, or a gold-tin paste can be used.

On the other main surface B of the semiconductor device with a through electrode obtained in this embodiment, an electrode pad 40 and a wiring 41 as shown in FIG. 6A, or FIG. Metal bumps 42 as shown in FIG.
Moreover, since the semiconductor device with a through electrode obtained in this embodiment can be electrically connected to the front and back by the through electrode 35, it is possible to stack the devices and reduce the size of the element.

  In this embodiment, by patterning the first metal thin film 33 or the second metal thin film 34, the electrode pad 38 and the wiring 39 are formed at the same time, and the electronic device 31 and the through electrode 37 are electrically connected. However, the present invention is not limited to this, and for example, the electronic device 31 and the electrode pad 38 can be connected by wire bonding using a metal wire.

DESCRIPTION OF SYMBOLS 11,30 ... Semiconductor substrate, 12, 32 ... 1st silicon oxide film, 13, 35 ... Fine pore, 14, 36 ... 2nd silicon oxide film, 15, 33 ... 1st metal thin film, 16, 34 ... 2nd metal thin film, 17, 37 ... penetrating electrode, 31 ... electronic device.

Claims (5)

A method of manufacturing a semiconductor device with a through electrode for wiring between main surfaces of a semiconductor substrate on which a device is formed in advance,
A first insulating layer forming step of forming a first insulating layer on at least one main surface of the semiconductor substrate on which a device is formed;
Following the first insulating layer forming step, a thin film forming step of forming a metal thin film on the first insulating layer;
Next to the thin film forming step, without exposing the metal thin film, a pore forming step of forming pores reaching the first insulating layer directly below the metal thin film from the other main surface of the semiconductor substrate;
Following the pore formation step, a second insulating layer is formed on the pore wall of the pore, the back surface of the first insulating layer in the pore, and the other main surface of the semiconductor substrate, and Reactive Ion Etching When the second insulating layer at the end of the pore and the first insulating layer are removed by the method to expose the metal thin film to the pore, the metal forming the metal thin film is A second insulating layer forming step for preventing the metal from scattering and adhering directly to the pore wall surface of the pore;
Subsequent to the second insulating layer forming step, the second insulating layer at the end of the pore and the first insulating layer are removed by a reactive ion etching method, and the pore An insulating layer removing step for exposing the metal thin film;
A method for manufacturing a semiconductor device with a through electrode, comprising: a conductive substance filling step of filling the pores with a conductive substance after the insulating layer removing step.  The said insulating layer removal process WHEREIN: The said 2nd insulating layer and the said 1st insulating layer of the edge part of the said pore are removed continuously by Reactive Ion Etching method. The manufacturing method of the semiconductor device with a penetration electrode of description.  3. The method of manufacturing a semiconductor device with a through electrode according to claim 1, wherein in the second insulating layer forming step, the second insulating layer is formed by a plasma CVD method or a sputtering method.  The method for manufacturing a semiconductor device with a through electrode according to any one of claims 1 to 3, wherein the pores are formed by a deep-reactive ion etching method. 5. The method of manufacturing a semiconductor device with a through electrode according to claim 1, wherein the metal thin film is formed by laminating two or more layers of different kinds of metals.

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