JP2006073838A - Method of manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress increase of manufacturing costs to be as low as possible, in a method of manufacturing a chip-sized package type semiconductor device. <P>SOLUTION: Ink jet printing of a first organic material is selectively performed, by forming a first opening 13w exposing a part of a pad electrode 12 on the surface of a semiconductor substrate 10 with the pad electrode 12 being formed via an insulating film 11. Afterwards, the first organic material is solidified by baking to form an interlayer insulating film 13. Ink jet printing of conductive paste is then performed on the layer insulating film 13 including the first opening 13w, according to a predetermined pattern. The conductive paste is then solidified by baking to form a wiring layer 18. Ink jet printing of a second organic material is then selectively performed on the interlayer insulating film 13, including the wiring layer 18. The second organic material is then solidified by baking, and a protective layer is formed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a method for manufacturing a chip size package type semiconductor device.

  In recent years, a chip size package has attracted attention as a package technology. The chip size package means a small package having an outer dimension substantially the same as the outer dimension of the semiconductor chip. Conventionally, BGA (Ball Grid Array) type and LGA (Land Grid Array) type semiconductor devices are known as chip size package type semiconductor devices. In these BGA type and LGA type semiconductor devices, a plurality of electrode portions (ball-shaped electrodes in the case of BGA type) electrically connected to the pad electrode of a semiconductor chip are arranged in a grid pattern on one main surface of the package. It is.

  When incorporating this BGA type or LGA type semiconductor device into an electronic device, each conductive terminal is crimped to a wiring pattern on the printed circuit board, so that a semiconductor chip and an external circuit mounted on the printed circuit board are connected. Electrically connected.

  Such BGA type and LGA type semiconductor devices have a larger number of chip size packages than other types of chip size packages such as SOP (Small Outline Package) and QFP (Quad Flat Package) having lead pins protruding from the side. The electrode portion can be provided and can be downsized. A BGA type or LGA type semiconductor device has a use as a chip size package for a CCD (Charge Coupled Device) camera mounted on a mobile phone, for example.

  The above-described conventional LGA type semiconductor device is manufactured, for example, by a manufacturing method through the following steps. A part of the process is shown in FIGS. 6 to 8 are cross-sectional views showing a method of manufacturing a semiconductor device according to a conventional example.

  First, as shown in FIG. 6, a semiconductor substrate 50 is prepared by being divided by a dicing line (not shown). Here, an electronic device such as a CCD (not shown) is formed on the surface of the semiconductor substrate 50, and a pad electrode 52 is formed via an insulating film 51.

  Next, an interlayer insulating film 53 is selectively formed on the surface of the semiconductor substrate 50. The interlayer insulating film 53 is made of, for example, a photosensitive resist material. In the selective formation of the interlayer insulating film 53, for example, after a photosensitive resist material is formed on the surface of the semiconductor substrate 50, a part of the pad electrode 52 is formed by photolithography using a mask (not shown) having a predetermined pattern. An opening 53w that exposes is formed. Next, a barrier layer and a seed layer (hereinafter collectively referred to as “barrier seed layer 54”) are formed on the interlayer insulating film 53 including a part of the pad electrode 52 exposed in the opening 53w. To do.

  Then, a resist layer 55 is selectively formed on the barrier seed layer 54 in accordance with a predetermined pattern including a part of the pad electrode 52. Thereafter, the wiring layer 58 is selectively formed on the barrier seed layer 54 using the resist layer 55 as a mask. The wiring layer 58 is made of, for example, copper. Alternatively, the wiring layer 58 is formed by selectively forming a resist layer (not shown) corresponding to a predetermined pattern on the surface of the semiconductor substrate 50, and then using this resist layer as a mask and sputtering using a metal such as aluminum. Is done.

  Next, although not shown, a protective layer exposing a part of the wiring layer is formed on the back surface of the semiconductor substrate including the wiring layer. The protective layer is made of, for example, a photosensitive resist material. A part of the exposed wiring layer becomes an electrode portion connected to the circuit board. Note that in the case where the semiconductor device is a BGA type, a conductive terminal may be formed over part of the wiring layer.

  Finally, the semiconductor substrate is separated into a plurality of semiconductor chips by dicing along a dicing line (not shown).

In addition, as a technical document relevant to the technique mentioned above, the following patent documents are mentioned, for example.
JP 2000-243729 A

  However, in the step of plating the wiring layer 58 in the manufacturing method of the chip size package type semiconductor device according to the conventional example as described above, the resist layer 55 is used as a mask for patterning the wiring layer 58 into a predetermined pattern. In need of selective formation. Even when the wiring layer 58 is formed by sputtering, it is necessary to selectively form a resist layer as a mask for patterning the wiring layer 58 in accordance with a predetermined pattern.

  Further, in the step of forming the interlayer insulating film 53 exposing a part of the pad electrode 52 or the step of forming a protective layer exposing a part of the wiring layer 58, the interlayer insulating film 55 and a part of the protective layer are removed. In order to achieve this, it is necessary to perform photolithography (exposure and development processing) through a mask having a predetermined pattern.

  That is, formation of each layer on the semiconductor substrate on which the pad electrode is formed requires a plurality of different processes. For this reason, there has been a problem that the flow of the manufacturing process becomes complicated and the manufacturing cost increases.

  Therefore, the present invention suppresses an increase in manufacturing cost as much as possible in a manufacturing method of a chip size package type semiconductor device.

  The semiconductor device manufacturing method of the present invention has been made in view of the above problems, and a part of the pad electrode is formed on the surface of the semiconductor substrate on which the pad electrode is formed via the first insulating film. A step of selectively inkjet-printing the first organic material so as to form an exposed first opening; a step of baking the first organic material to form a second insulating film; A step of ink-jet printing a conductive paste on a second insulating film including a part of the pad electrode exposed at the opening of 1 in accordance with a predetermined pattern; and baking the conductive paste to form a wiring layer Forming a second opening exposing a part of the pad electrode on the second insulating film including the wiring layer and the second insulating material, and selectively printing the second organic material on the second insulating film; And baking the second organic material Forming a Mamoruso, characterized by having a.

  Further, the semiconductor substrate and each layer stacked thereon are diced to be separated into a semiconductor device including a plurality of semiconductor chips and each layer stacked thereon.

  According to the present invention, a plurality of different layers (interlayer insulating film, wiring layer, protective layer, etc.) can be formed on a semiconductor substrate on which a pad electrode is formed by only two steps of ink jet printing and baking. . At this time, it is not necessary to use a mask for patterning or photolithography.

  Therefore, a plurality of processes different depending on each layer as in the conventional example is not required, and the flow of the manufacturing process can be simplified as much as possible. As a result, an increase in manufacturing cost of the semiconductor device can be suppressed as much as possible.

  Ink jet printing can print different materials on a semiconductor substrate using the same apparatus. For this reason, it is not necessary to introduce different facilities for each material, so that it is possible to suppress an increase in capital investment related to the manufacture of semiconductor devices as much as possible.

  Next, a method for manufacturing a semiconductor device according to an embodiment of the present invention will be described with reference to the drawings. 1 to 5 are cross-sectional views showing a method for manufacturing a semiconductor device according to this embodiment. 1 to 5 show the vicinity of a dicing line (not shown) in the semiconductor substrate.

  First, as shown in FIG. 1, a semiconductor substrate 10 divided by a dicing line (not shown) is prepared. Here, an electronic device (not shown) is formed on the surface of the semiconductor substrate 10. A pad electrode 12 is formed on the surface of the semiconductor substrate 10 via an insulating film 11 which is a first insulating film.

  An electronic device (not shown) is assumed to be, for example, an image sensor composed of a CCD (Charge Coupled Device) or the like, a light receiving element such as an infrared sensor, or a light emitting element. Alternatively, the electronic device (not shown) may be an electronic device other than the light receiving element and the light emitting element. The semiconductor substrate 10 is made of, for example, a silicon substrate, but may be a substrate made of other materials.

  Next, as shown in FIG. 2, a first organic material (which will later become the interlayer insulating film 13) is selectively inkjet printed on the surface of the semiconductor substrate 10 including an electronic device (not shown). The first organic material is not particularly limited, but is preferably a resist material, for example.

  In the region of the surface of the semiconductor substrate 10 where the first organic material is printed, the movable nozzle 100 facing the surface moves in the horizontal direction, and the first organic material is moved from the nozzle 100 to the surface. Is sprayed. On the other hand, in the region of the surface of the semiconductor substrate 10 where the first organic material is not printed, the nozzle 100 moves in the horizontal direction, but the first organic material is not sprayed. Thus, the first organic material is selectively formed on the surface of the semiconductor substrate 10 so as to have the first opening 13w that exposes part of the pad electrode.

  Next, the semiconductor substrate 10 on which the first organic material is formed is baked at a predetermined temperature. Here, the semiconductor substrate 10 on which the first organic material is printed is baked for about 60 minutes at a temperature of about 150 ° C., for example. However, the temperature and time required for this baking are not limited to the above temperature and time because they vary depending on the properties of the first organic material. By this baking, the first organic material formed on the semiconductor substrate 10 is solidified to form the interlayer insulating film 13 as the second insulating film having the first opening 13w.

  Note that any material other than the first organic material may be ink-jet printed in order to form the interlayer insulating film 13 as long as it can be used for ink-jet printing and can later become the interlayer insulating film 13. .

  Next, as shown in FIG. 3, a conductive paste (which will later become the wiring layer 18) is selectively inkjet printed on a predetermined region of the interlayer insulating film 13 including the first opening 13w. Here, the conductive paste is printed so as to cover the pad electrode 12 exposed in the first opening 13w.

  The conductive paste is not particularly limited, but is preferably made of, for example, a silver paste. Furthermore, the silver paste preferably contains silver (Ag) particles having a diameter of about several nanometers to several tens of nanometers.

  In the region of the surface of the semiconductor substrate 10 where the conductive paste is printed, the movable nozzle 100 facing the surface moves in the horizontal direction, and the conductive paste is sprayed from the nozzle 100 onto the surface. . On the other hand, in the region of the surface of the semiconductor substrate 10 where the conductive paste is not printed, the nozzle 100 moves in the horizontal direction, but the conductive paste is not sprayed. Thus, the conductive paste is selectively formed on the surface of the semiconductor substrate 10 according to a predetermined pattern.

  Next, the semiconductor substrate 10 on which the conductive paste is formed is baked at a predetermined temperature. Here, the semiconductor substrate 10 on which the conductive paste is formed is baked for about 10 minutes at a temperature of about 150 ° C., for example. However, the temperature and time required for this baking differ depending on the conductive paste, and are not limited to the above temperature and time. By this baking, the conductive paste formed on the semiconductor substrate 10 is solidified to form the wiring layer 18 having a predetermined pattern.

  When the wiring layer 18 is a silver paste, there is no need to worry about copper contamination that may occur when a copper (Cu) paste is used for the wiring layer due to the nature of silver (Ag). Further, in this case, due to the property of silver (Ag), it is possible to suppress as much as possible the deterioration of resistance to electromigration that easily occurs when aluminum (Al) is used for the wiring layer.

  In addition, if it can be used for inkjet printing and can become the wiring layer 18 later, in order to form the wiring layer 18, a conductive paste made of a material other than the silver paste (for example, copper paste) is used. Inkjet printing may be used. Alternatively, the conductive paste may be mixed with a predetermined solvent (for example, toluene, xylene, etc.) and the mixture may be inkjet printed.

  Although not shown, before the conductive paste for forming the wiring layer 18 is inkjet-printed, a predetermined conductive paste for forming the barrier metal layer is inkjet-printed, and the semiconductor substrate 10 is baked. A barrier metal layer made of the conductive paste may be formed.

  Next, as shown in FIG. 4, a second organic material (to be a protective layer 21 later) is formed on the surface of the interlayer insulating film 13 including the wiring layer 18 so as to open a part of the wiring layer 18. ) Selectively inkjet printing. The second organic material is not particularly limited, but is preferably a resist material, for example.

  In the region of the surface of the semiconductor substrate 10 where the second organic material is printed, the movable nozzle 100 facing the surface moves in the horizontal direction, and the second organic material is moved from the nozzle 100 to the surface. Is sprayed. On the other hand, in the region of the surface of the semiconductor substrate 10 where the second organic material is not printed, the nozzle 100 moves in the horizontal direction, but the second organic material is not sprayed. In this way, the second organic material is selectively formed on the surface of the semiconductor substrate 10 so as to have the second opening 21 w exposing a part of the wiring layer 18.

  Next, the semiconductor substrate 10 on which the second organic material is formed is baked at a predetermined temperature. Here, the semiconductor substrate 10 on which the second organic material is printed is baked for about 60 minutes at a temperature of about 150 ° C., for example. However, the temperature and time required for this baking differ depending on the nature of the second organic material, and are not limited to the above temperature and time.

  By this baking, the second organic material formed on the semiconductor substrate 10 is solidified to form the protective layer 21 having the second opening 21w. Furthermore, a conductive terminal (not shown) may be formed on a part of the wiring layer 18 exposed at the second opening to connect the pad electrode 12 and a circuit board (not shown).

  In addition, in order to form the protective layer 21 as long as it can be used for inkjet printing and can become the protective layer 21 later, materials other than the second organic material may be inkjet printed.

  Finally, as shown in FIG. 5, by dicing along a dicing line (not shown), the semiconductor substrate 10 and each layer stacked thereon are separated into a plurality of semiconductor chips 10A and a semiconductor device composed of each layer stacked thereon. .

  As described above, according to the present invention, a plurality of different layers (interlayer insulating film 13, wiring layer 18, protective layer 21) are formed on the semiconductor substrate 10 on which the pad electrode 12 is formed by ink jet printing and baking 2. It can be formed by only one process. At this time, it is not necessary to use a mask for patterning or photolithography.

  Therefore, a plurality of processes different depending on each layer as in the conventional example is not required, and the flow of the manufacturing process can be simplified as much as possible. As a result, an increase in manufacturing cost of the semiconductor device can be suppressed as much as possible.

  In addition, inkjet printing can print different materials on the semiconductor substrate 10 using the same apparatus. For this reason, it is not necessary to introduce different facilities for each material, so that it is possible to suppress an increase in capital investment related to the manufacture of semiconductor devices as much as possible.

  In the above-described embodiment, the interlayer insulating film 13, the wiring layer 18, and the protective layer 21 are formed on the surface of the semiconductor substrate 10, but the present invention is not limited to this. That is, the present invention is also applied when an interlayer insulating film, a wiring layer, or a protective layer is formed on the back surface of the semiconductor substrate 10.

  Furthermore, the present invention is also applied to a semiconductor device having a multilayer structure in which a plurality of interlayer insulating films, wiring layers, or protective layers are stacked. In addition, the present invention provides a semiconductor device in which a layer other than an interlayer insulating film, a wiring layer, or a protective layer is formed as long as it is a layer that can be printed by inkjet printing and is made of a material that is solidified by baking. The same applies.

It is sectional drawing which shows the manufacturing method of the semiconductor device which concerns on embodiment of this invention. It is sectional drawing which shows the manufacturing method of the semiconductor device which concerns on embodiment of this invention. It is sectional drawing which shows the manufacturing method of the semiconductor device which concerns on embodiment of this invention. It is sectional drawing which shows the manufacturing method of the semiconductor device which concerns on embodiment of this invention. It is sectional drawing which shows the manufacturing method of the semiconductor device which concerns on embodiment of this invention. It is sectional drawing which shows the manufacturing method of the semiconductor device which concerns on a prior art example. It is sectional drawing which shows the manufacturing method of the semiconductor device which concerns on a prior art example. It is sectional drawing which shows the manufacturing method of the semiconductor device which concerns on a prior art example.

Claims (5)

The first organic material is selectively formed by forming a first opening that exposes a part of the pad electrode on the surface of the semiconductor substrate on which the pad electrode is formed via the first insulating film. A step of ink-jet printing,
Baking the first organic material to form a second insulating film;
A step of inkjet printing a conductive paste on the second insulating film including a part of the pad electrode exposed in the first opening according to a predetermined pattern;
Baking the conductive paste to form a wiring layer;
A step of selectively inkjet-printing a second organic material so as to form a second opening exposing a part of the pad electrode on the second insulating film including the wiring layer; ,
Baking the second organic material to form a protective layer;
And a step of dicing the semiconductor substrate and each layer stacked thereon to separate the semiconductor device from a plurality of semiconductor chips and each layer stacked thereon. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the conductive paste is a silver paste. The method of manufacturing a semiconductor device according to claim 1, wherein the conductive paste is a copper paste. The method of manufacturing a semiconductor device according to claim 1, wherein the first organic material is a resist material. The method of manufacturing a semiconductor device according to claim 1, wherein the second organic material is a resist material.