JP3039463B2 - Semiconductor device and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device in which active elements formed on a semiconductor element are hermetically sealed, and a method for manufacturing the same.

[0002]

2. Description of the Related Art In a conventional semiconductor device, it may be necessary to hermetically seal a semiconductor device or a device having a high-frequency circuit using the semiconductor device on a substrate. FIG. 10 is a cross-sectional view illustrating an example of a conventional semiconductor device.

In a conventional semiconductor device, as shown in FIG. 10, a semiconductor element 92 is mounted on a surface of a metal carrier 91 as a substrate. A through line 96 is formed around the semiconductor element 92 on the surface of the metal carrier 91, and a line 95 is formed around the through line 96. The electrical connection between the semiconductor element 92 and the through line 96 and the electrical connection between the through line 96 and the line 95 are made by a boding wire 97. Hermetic sealing is performed by bonding an upper lid 93 to a surface of the metal carrier 91 provided with the semiconductor element 92 and the like so as to cover the semiconductor element 92. In this case, the line 95 passing between the metal carrier 91 and the upper lid 93
, An input signal and an output signal are exchanged, or a bias is applied.

FIG. 11 is a sectional view showing another example of a conventional semiconductor device. In the conventional semiconductor device shown in FIG. 11, a semiconductor element 102 is mounted on the surface of a metal carrier 101, and a through line 10 is formed around the semiconductor element 102 on the surface of the metal carrier 101 as a substrate.
3 are formed. Semiconductor element 102 and through line 1
03 are electrically connected by the internal wiring 104. A resin 105 is formed on an exposed portion of the surface of the semiconductor element 102 and a part of the surface of the internal wiring 104, and the semiconductor element 102 is covered with the resin 105 to perform hermetic sealing.

[0005]

However, FIG.
In the conventional semiconductor device shown in (1), it is essential that the surface accuracy of the surface of the metal carrier 91 on the semiconductor element 92 side and the bonding surface of the upper cover 93 be good so that the upper cover 93 is in close contact with the metal carrier 91. When the carrier 91 and the upper lid 93 are manufactured, excellent processing accuracy is required. At this time, for example, if the material of the upper lid 93 is plastic or ceramic, it is not easy to obtain high processing accuracy,
Further, even when a metal material is used as the material of the upper lid 93, there is a problem that the price is increased.

In addition, the conventional semiconductor device shown in FIG. 11 has a problem that remarkable deterioration of high-frequency characteristics is caused by an increase in dielectric loss and parasitic capacitance of the resin 105 particularly at a high frequency exceeding several GHz. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a hermetically sealed semiconductor device and a method of manufacturing the same at low cost and without damaging high frequency characteristics in view of the above-mentioned problems of the prior art. .

[0008]

According to the present invention, there is provided a semiconductor device having a semiconductor element having an active element formed on one surface and a substrate on which the semiconductor element is mounted. recess is formed on one surface, and the concave side surface of the substrate, and the surface of the active element side of the semiconductor element, photoresistive as the active element fits in the recess
It is characterized in that it is bonded via a strike .

[0009] In the above invention, the inside of the concave portion of the substrate,
The atmosphere when the substrate and the semiconductor element are bonded together via the photoresist is sealed, and the active element of the semiconductor element is hermetically sealed.

Preferably, a semiconductor is used as a material of the substrate. Thus, since the substrate is formed through a semiconductor manufacturing process with high processing accuracy, the surface accuracy of the substrate is increased, and the adhesion between the substrate and the semiconductor element is improved. Therefore, high hermetic performance is ensured by hermetic sealing of the active element.

Further, it is preferable that the semiconductor element is an integrated circuit.

[0012]

[0013]

[0014]

Furthermore, it is preferable that a conductive metal layer is formed on at least a part of the surface of the semiconductor element or the substrate. Thereby, the active element formed on the semiconductor element is shielded by the conductive metal layer.

Further, it is preferable that a conductive metal layer is formed on the inner wall of the concave portion of the substrate. Thus, the concave side of the active element formed in the semiconductor element is covered with the conductive metal layer formed on the inner wall of the concave section, and the active element is shielded by the conductive metal layer.

Further, an external terminal is formed on a surface of the semiconductor element opposite to the active element side, and a via hole or a via hole for electrically connecting the external terminal and the active element to the semiconductor element. Preferably, a through hole is formed. Thus, the active element is electrically connected to the outside of the semiconductor device via the external terminal.

Further, it is preferable that a columnar projection is formed inside the concave portion of the substrate, and a tip of the columnar projection contacts the semiconductor element or an active element formed on the semiconductor element. Thereby, heat generated from the semiconductor element and the active element is radiated from the substrate to the outside of the semiconductor device via the columnar protrusion, and a semiconductor device having high heat dissipation is obtained.

Further, a columnar projection is formed inside the concave portion of the substrate, and a conductive layer is formed on the tip end surface and side surfaces of the columnar projection, and the semiconductor element and the substrate are connected via the conductive layer. Are preferably electrically connected. Thus, an integrated circuit is also formed on the substrate, and the integrated circuit on the substrate and the active element of the semiconductor element are electrically connected via the conductive layer formed on the tip end surface and side surface of the outer columnar projection. can do. Thus, a semiconductor device having a small-sized and higher-density integrated circuit can be obtained.

Further, an external terminal is formed on a surface of the substrate opposite to the concave side, and the substrate is electrically connected to the external terminal and the conductive layer on a tip end surface and a side surface of the columnar protrusion. It is preferable that a through-hole for connecting to the first hole be formed. Thus, external terminals electrically connected to the active element of the semiconductor element can be formed also on the surface of the substrate opposite to the semiconductor element.

Further, according to the present invention, a step of forming a plurality of concave portions corresponding to each of a plurality of active elements formed on one surface of a second semiconductor substrate on one surface of a first semiconductor substrate; Bonding the first semiconductor substrate and the second semiconductor substrate so that each active element of the semiconductor substrate fits into a recess corresponding to each active element;
The step of dividing the bonded semiconductor substrate into chips.

In the above invention, a part of the first semiconductor substrate on which the concave portion is formed and a part of the second semiconductor substrate on which the active element is formed are bonded so that the active element is accommodated in the concave portion. A combined semiconductor device is manufactured. Therefore,
Semiconductor devices in which active elements are housed in recesses and hermetically sealed are manufactured inexpensively and in large quantities.

Further, the present invention provides a step of forming a plurality of concave portions corresponding to each of a plurality of active elements formed on one surface of a second semiconductor substrate on one surface of a first semiconductor substrate. Bonding the first semiconductor substrate and the second semiconductor substrate so that each active element of the semiconductor substrate fits into a recess corresponding to each active element; and forming a through hole in the second semiconductor substrate. And a step of dividing the bonded first and second semiconductor substrates into chips in this order.

In the above invention, a semiconductor device is manufactured in which the active element is housed in the recess and hermetically sealed, and the active element is electrically connected to the outside of the recess through the through hole.

Further, before the step of forming the plurality of recesses on one surface of the first semiconductor substrate, a sapphire substrate is attached to the other surface of the first semiconductor substrate, and the sapphire substrate is bonded on one surface of the first semiconductor substrate. After forming a plurality of recesses, a scribe line is formed on the surface of the first semiconductor substrate on the side of the recess, and the sapphire substrate and the scribe line are formed when performing a step of bonding the first and second semiconductor substrates. It is preferable that the first semiconductor substrate and the second semiconductor substrate are aligned by seeing through the surface of the second semiconductor substrate on the active element side. In such a method of manufacturing a semiconductor device, when the first semiconductor substrate and the second semiconductor substrate are bonded to each other, the active element of the second semiconductor substrate is placed in the concave portion of the first semiconductor substrate. Accuracy of alignment is obtained.

Further, when performing the step of bonding the first and second semiconductor substrates, a metal layer is formed on a portion other than the concave portion on the concave side of the first semiconductor substrate. It is preferable that the first and second semiconductor substrates are bonded to each other via the substrate.

Further, it is preferable that a metal layer is further formed on the inner wall of the concave portion of the first semiconductor substrate.

Further, when performing the step of bonding the first and second semiconductor substrates, an organic compound is formed on a portion other than the concave portion of the concave-side surface of the first semiconductor substrate,
It is preferable that the first and second semiconductor substrates are bonded together via the organic compound.

Further, when performing the step of bonding the first and second semiconductor substrates, a photoresist is formed on a portion other than the concave portion on the concave side of the first semiconductor substrate, and the photoresist is formed. It is preferable that the first and second semiconductor substrates are bonded to each other via the substrate.

[0030]

Next, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 is a perspective view for explaining a semiconductor device according to a first embodiment of the present invention. FIG. 1A shows a state in which the semiconductor device of the present embodiment is disassembled, and FIG. 1B shows a state of the semiconductor device of the present embodiment from the state shown in FIG. The assembled state is shown.

In the semiconductor device of this embodiment, FIG.
As shown in FIG. 1, a semiconductor integrated circuit substrate 2 which is a semiconductor element
The ground conductor 3, the high-frequency signal electrode pad 4, and the bias supply electrode pad 5 are formed at desired positions on the surface opposite to the silicon substrate 1 side. Active elements such as transistors (not shown) are formed on the surface of the semiconductor integrated circuit substrate 2 on the silicon substrate 1 side. The ground conductor 3, the high-frequency signal electrode pad 4, and the bias supply electrode pad 5 are respectively formed on the active element side of the semiconductor integrated circuit board 2 by through holes (not shown) formed at predetermined positions of the semiconductor integrated circuit board 2. It is electrically connected to an electrode (not shown) formed on the surface. On the other hand, a concave portion 6 is formed on one surface of the silicon substrate 1 on which the semiconductor integrated circuit substrate 2 is mounted.

As shown in FIG. 1B, in the semiconductor device according to the present embodiment, the surface of the silicon substrate 1 on the side of the recess 6 and the surface of the semiconductor integrated circuit substrate 2 on the side of the active element are formed in the recess 6 by the semiconductor. It is bonded so that the active elements of the integrated circuit board 2 are accommodated. At this time, a clean atmosphere is sealed in the concave portion 6 by introducing a nitrogen gas or the like into the concave portion 6. As described above, since no resin is used for hermetic sealing, there is no deterioration in high-frequency characteristics due to an increase in dielectric loss or parasitic capacitance of the resin.

Since both the silicon substrate 1 and the semiconductor integrated circuit substrate 2 are semiconductor substrates, these substrates are:
Manufactured through a semiconductor manufacturing process with high processing accuracy,
The surface accuracy of each bonding surface is good. Therefore, high airtightness of the recess 6 can be ensured. Instead of the silicon substrate 1, another semiconductor substrate or a substrate formed of a material to which a semiconductor process can be applied can be used. If an integrated circuit is formed on the silicon substrate 1 on which the concave portions 6 are formed, a semiconductor device integrated at a higher density can be obtained.

Next, a method of manufacturing the semiconductor device shown in FIG. 1 will be described with reference to FIG. FIG. 2 is a diagram illustrating the method for manufacturing the semiconductor device according to the present embodiment. The semiconductor device of the present embodiment is manufactured through the steps shown in FIGS. 2A to 2E shown in FIG.

First, in FIG. 2A, a silicon substrate 712 as a first semiconductor substrate is formed.

Next, in FIG. 2B, a plurality of recesses 713 are formed on the surface of the silicon substrate 712 through processes such as photoresist coating, mask exposure, and etching removal. Each concave portion 713 corresponds to each of a plurality of active elements formed on one surface of a semiconductor integrated circuit substrate 715 as a second semiconductor substrate, which will be described later with reference to FIG.

Next, referring to FIGS. 2C and 2D, a semiconductor integrated circuit substrate 715 formed in another step and having a plurality of active elements (not shown) formed on one surface is replaced with a silicon substrate 7.
It is stuck on the surface of the twelve concave portions 713 side. At this time, the surface of the semiconductor integrated circuit substrate 715 on the active element side is
12, each active element of the semiconductor integrated circuit substrate 715 is placed in a recess 7 corresponding to each active element.
Adjustment is made to fit in 13.

Next, in FIG. 2E, a scribe line 716 is formed on the surface of the semiconductor integrated circuit substrate 715 opposite to the active element side.

Thereafter, the semiconductor device having the structure shown in FIG. 1 is manufactured by dividing the chip by the scribe lines 716.

According to the above-described semiconductor device manufacturing method,
When a semiconductor element is mounted on a substrate, a semiconductor device in which an active element of the semiconductor element is accommodated in a concave portion of the substrate is obtained. Further, in such a method for manufacturing a semiconductor device, a semiconductor process having extremely high processing accuracy and surface accuracy is used, and therefore, a large number of semiconductor devices having excellent sealing performance can be manufactured at low cost. Therefore, it is possible to manufacture a large number of inexpensive semiconductor devices that are hermetically sealed so that high-frequency characteristics are not impaired.

Next, a specific example of the method of manufacturing the semiconductor device described with reference to FIG. 2 will be described.

First, in FIGS. 2A and 2B, AuSn is deposited on one surface of a silicon substrate 712 by a sputtering method. A on silicon substrate 712
A photoresist is applied to the surface of the uSn, and the photoresist is exposed using a mask, and then the photoresist in a region where the concave portion 713 is formed is removed. AuSn exposed by removing the photoresist is removed by milling. Thereby, the silicon substrate 712
In the region where the concave portion 713 is formed, the silicon substrate 71
2 is exposed. Then, a plurality of recesses 713 are formed in the exposed portions of the silicon substrate 712 by wet etching. After that, the photoresist on the silicon substrate 712 is removed. 2A and 2B, a recess 713 is formed on one surface of the silicon substrate 712, and the recess 713 is formed on one surface of the silicon substrate 712.
AuSn is left in other parts.

Next, referring to FIGS. 2C and 2D, the semiconductor integrated circuit substrate 715 containing GaAs as a main component manufactured in another process is inserted into the concave portion 7 of the silicon substrate 712.
Glue to the 13 side. Here, a plurality of active elements are formed on one surface of the semiconductor integrated circuit substrate 715,
The surface of the semiconductor integrated circuit substrate 715 on the side of the active element and the surface of the silicon substrate 712 on the side of the concave part 713 are opposed to each other, and alignment is performed so that each active element fits in the concave part 713 corresponding to each active element. Further, the semiconductor integrated circuit board 71
5 of the silicon substrate 712 on the active element side surface.
Au is vapor-deposited on portions other than the portion corresponding to 13 by a sputtering method. Semiconductor integrated circuit board 71
5 and the silicon substrate 712, the Au remaining on one surface of the silicon substrate 712 as described above.
The silicon substrate 712 and the semiconductor integrated circuit substrate 715 are joined by thermocompression bonding in an environment of 300 degrees Celsius using Sn or Au deposited on the surface of the semiconductor integrated circuit substrate 715 on the active element side as an adhesive. Thereafter, though not shown, formation of through holes and formation of external terminals and ground conductors are performed.

Next, in FIG. 2E, a scribe line 716 is formed on the surface of the semiconductor integrated circuit substrate 715 on the side opposite to the silicon substrate 712 by using a diamond cutter or the like.

Thereafter, the semiconductor device is manufactured by dividing the chip by the scribe lines 716.

In the above-described method of manufacturing a semiconductor device, a photoresist is used as a mask and AuSn serving as an adhesive is used.
And the recess 713 is formed, but the formation of the recess 713 and the formation of the adhesive may be performed in different steps.

(Second Embodiment) The semiconductor device according to the second embodiment of the present invention is different from the first embodiment in the method of manufacturing the semiconductor device. Hereinafter, a method for manufacturing a semiconductor device will be described with reference to FIGS.

FIGS. 3 and 4 are views for explaining a method of manufacturing the semiconductor device of the present embodiment. The semiconductor device of the present embodiment is manufactured through the steps shown in FIGS. 3A and 4A to FIG. 4F.

First, in FIG. 3A, a silicon substrate 812 as a first semiconductor substrate is replaced with a sapphire substrate 811.
Paste on the surface of

Next, in FIG. 3B, a plurality of recesses 813 are formed on the surface of the silicon substrate 812 on the side opposite to the sapphire substrate 811 through processes such as photoresist coating, mask exposure and etching removal. I do. Each of the recesses 813 is provided with a second recess 813 described later with reference to FIG.
Corresponds to each of a plurality of active elements formed on one surface of a semiconductor integrated circuit substrate 815 which is a semiconductor substrate.

Next, in FIG. 3C, a first scribe line 814 is formed on the surface of the silicon substrate 812 on the side of the concave portion 813 by etching using a photoresist or a metal film as a mask to form a chip. To divide.

Next, in FIG. 4 (d) and FIG. 4 (e), the active element (not shown) is formed on one side by another process.
Is attached to the surface of the silicon substrate 812 on the concave side 813 side. At this time,
The surface of the semiconductor integrated circuit substrate 815 on the side of the active element is opposed to the surface of the silicon substrate 812 on the side of the concave part 813, and alignment is performed so that each active element of the semiconductor integrated circuit substrate 815 fits in the concave part 813 corresponding to each active element. I do. In this step, the bonding surface of the semiconductor integrated circuit substrate 815 on the active element side can be seen through the sapphire substrate 811 and the first scribe line 814 from the surface of the sapphire substrate 811 opposite to the silicon substrate 812 side. The alignment accuracy is obtained.

The method of aligning the silicon substrate 812 with the semiconductor integrated circuit substrate 815 is as follows: when the bonding surface on the active element side of the semiconductor integrated circuit substrate 815 is seen through the sapphire substrate 811 and the first scribe line 814. The silicon substrate 812 and the semiconductor integrated circuit substrate 815 are so arranged that the elements constituting the circuit of the semiconductor integrated circuit substrate 815 cannot be seen from the first scribe line 814.
Position. Alternatively, as a method of performing the alignment more accurately, a mark for performing the alignment is formed in advance at a predetermined position on the bonding surface of the semiconductor integrated circuit substrate 815 on the active element side. The position of the mark formed on the semiconductor integrated circuit substrate 815 is such that when the alignment is completed, the semiconductor integrated circuit substrate 815 is passed through the first scribe line 814 from the surface of the sapphire substrate 811 opposite to the silicon substrate 812 side. It is desirable that the mark of can be seen. Then, through the sapphire substrate 811 and the first scribe line 814, the bonding surface on the active element side of the semiconductor integrated circuit substrate 815 is seen through, and the semiconductor integrated circuit substrate 8
The silicon substrate 812 and the semiconductor integrated circuit substrate 815 are positioned while observing the fifteen marks.

Next, in FIG. 4F, a second scribe line 816 is formed on the surface of the semiconductor integrated circuit substrate 815 on the side opposite to the active element side.

Thereafter, the semiconductor device is manufactured by dividing the chip at the second scribe line 816.

As described above, in the method of manufacturing a semiconductor device according to the present embodiment, after the recess 813 of the silicon substrate 812 attached to the sapphire substrate 811 is formed, the surface of the silicon substrate 812 on the recess 813 side is formed. One scribe line 814 is formed. Therefore, the silicon substrate 81
2 and the surface of the semiconductor integrated circuit substrate 715 on the active element side, the sapphire substrate 811 and the first surface of the sapphire substrate 811 are bonded together from the surface on the side opposite to the silicon substrate 812 side. By seeing through the surface of the semiconductor integrated circuit substrate 815 on the active element side through the scribe line 814, high alignment accuracy can be obtained.

(Third Embodiment) FIG. 5 is a sectional view showing a semiconductor device according to a third embodiment of the present invention.

In the semiconductor device of the present embodiment, as shown in FIG. 5, a transistor 22 as an active element and a transistor 22 electrically connected to a surface of the semiconductor integrated circuit substrate 21 as a semiconductor element on the silicon substrate 20 side. Connected wiring 2
3 are formed. External terminals 25 and a ground conductor 26 are formed on a surface of the semiconductor integrated circuit board 21 opposite to the transistor 22 side. A through hole 24 is formed at a predetermined position of the semiconductor integrated circuit board 21, and the wiring 23 and the external terminal 25 are electrically connected by the through hole 24. Further, a ground electrode (not shown) is formed on the surface of the semiconductor integrated circuit substrate 21 on the transistor 22 side. The ground electrode is formed by another through-hole (not shown) different from the through-hole 24 formed on the semiconductor integrated circuit board 21.
6 are electrically connected.

On the other hand, a concave portion 28 is formed on the surface of the silicon substrate 20 on the semiconductor integrated circuit substrate 21 side. The surface of the silicon substrate 20 on the side of the concave portion 28 and the surface of the semiconductor integrated circuit substrate 21 on the side of the transistor 22 are bonded via an adhesive 27 so that the transistor 22 is accommodated in the concave portion 28. As the adhesive 27, for example, a metal such as AuSn or an organic material such as a photoresist is used. However, the material is not particularly limited as long as it has a bonding function. The semiconductor integrated circuit board 21 is
At the time of bonding the silicon substrate 20 with the silicon substrate 20, an atmosphere at the time of bonding such as dried nitrogen is sealed.

As described above, in the semiconductor device of this embodiment, the transistor 22 of the semiconductor integrated circuit board 21 is housed in the recess 28 of the silicon substrate 20 and hermetically sealed.
Since the semiconductor integrated circuit substrate 21 and the silicon substrate 20 are manufactured through a semiconductor manufacturing process with extremely high processing accuracy, the surface accuracy of these substrates is good, and the semiconductor integrated circuit substrate 21 and the silicon substrate 20 Adhesion is improved. Therefore, a semiconductor device having excellent sealing performance can be obtained. Further, unlike a conventional semiconductor device, it is not necessary to use a resin for hermetic sealing, so that a hermetically sealed semiconductor device can be obtained without deteriorating high-frequency characteristics.

FIG. 6 is a sectional view showing a modification of the semiconductor device shown in FIG. The semiconductor device shown in FIG. 6 is different from the semiconductor device shown in FIG.
A surface opposite to the concave portion 28 side, a side surface of the silicon substrate 20,
In addition, a ground conductor 36 is formed as a conductive metal layer on the side surface of the semiconductor integrated circuit board 21.

In the semiconductor device shown in FIG. 6, since the semiconductor integrated circuit board 21 is covered with the ground conductors 26 and 36, the semiconductor integrated circuit board 21 is grounded except for the portion where the external terminals 25 are formed. Semiconductor integrated circuit board 21 is electrically shielded from outside by conductors 26 and 36.

FIG. 7 is a sectional view showing a modification of the semiconductor device shown in FIG. In the semiconductor device shown in FIG.
A concave portion 48 is formed on the surface of the silicon substrate 40 on the side of the semiconductor integrated circuit substrate 21, and a ground conductor 47 as a conductive metal layer is formed on the surface of the silicon substrate 40 on the side of the semiconductor integrated circuit substrate 21 or on the inner wall of the concave portion 48. Are formed. The surface of the silicon substrate 40 on the side of the concave portion 48 and the surface of the semiconductor integrated circuit substrate 21 on the side of the transistor 22 are bonded via a ground conductor 47. Then, the silicon substrate 40
Of the ground conductor 46 on the surface opposite to the concave portion 48 side, the side surface of the silicon substrate 40, and the side surface of the semiconductor integrated circuit substrate 21.
Are formed. The ground conductor 46 is a
Since it is also formed on the part exposed on the side of the semiconductor device,
The ground conductor 46 and the ground conductor 47 are electrically connected. The atmosphere when the semiconductor integrated circuit substrate 21 and the silicon substrate 40 are bonded together, such as dried nitrogen, is sealed inside the recess 48.

As a method of forming the ground conductor 47 of the semiconductor device described above, after forming the concave portion 713 of the silicon substrate 712 as shown in FIG. 2B of the first embodiment,
Alternatively, as shown in FIG. 3B of the second embodiment, after forming the concave portion 813 in the silicon substrate 812, a conductive metal is deposited on the surface of the silicon substrate on the concave side or the inner wall of the concave portion, Or to apply organic material of nature.

In the semiconductor device shown in FIG. 7, since the semiconductor integrated circuit board 21 is covered by the ground conductors 26, 46 and 47, the external terminals 2 of the semiconductor integrated circuit board 21
The ground conductors 26, 46, 4
7, the semiconductor integrated circuit board 21 is electrically shielded from the outside.

(Fourth Embodiment) FIG. 8 is a sectional view showing a semiconductor device according to a fourth embodiment of the present invention. In the semiconductor device of the present embodiment, as shown in FIG. 8, a transistor 52 as an active element and a transistor 52 are electrically connected to a surface of a semiconductor integrated circuit substrate 51 as a semiconductor element on the silicon substrate 50 side. The wiring 53 is formed. An external terminal 55 and a ground conductor 56 are formed on a surface of the semiconductor integrated circuit board 51 opposite to the transistor 52 side. Further, a through hole 54 is formed at a predetermined position of the semiconductor integrated circuit board 51, and the wiring 53 and the external terminal 55 are electrically connected by the through hole 54. Further, a ground electrode (not shown) is formed on the surface of the semiconductor integrated circuit substrate 51 on the transistor 52 side. The ground electrode is electrically connected to the ground conductor 56 by another through hole (not shown) formed in the semiconductor integrated circuit board 51 and different from the through hole 54.

On the other hand, a concave portion 59 is formed on the surface of the silicon substrate 50 on the side of the semiconductor integrated circuit substrate 51.
A columnar protrusion 58 is formed in a portion corresponding to the transistor 52 inside. The surface of the silicon substrate 50 on the side of the concave portion 59 and the surface of the semiconductor integrated circuit substrate 51 on the side of the transistor 52 are bonded together via the adhesive 57 so that the transistor 52 is accommodated in the concave portion 59. Here, the tip of the columnar projection 58 contacts the transistor 52. For example, the semiconductor integrated circuit board 5
When 1 is formed of GaAs, the heat generated in the semiconductor integrated circuit board 51 is efficiently radiated from the silicon substrate 50 having high thermal conductivity via the columnar projections 58.
In the present embodiment, the tip of the columnar projection 58 is brought into contact with the transistor 52, but the tip of the columnar projection 58 is connected to the electrode of an active element such as a transistor formed on the surface of the semiconductor integrated circuit board 51 on the transistor 52 side. You may contact. As in the third embodiment, the atmosphere when the semiconductor integrated circuit substrate 51 and the silicon substrate 50 are bonded to each other is sealed inside the concave portion 59.

As a method of forming the columnar projections 58 of the semiconductor device, as described in detail in the method of manufacturing the semiconductor device with reference to FIG.
In (b), when a photoresist is applied to the silicon substrate 712 to form the concave portion 713 and mask exposure is performed, columnar protrusions are formed on the surface of the silicon substrate 712 in a region where the concave portion 713 is formed. The photoresist is selectively left on the portion to be formed. Then, by performing the etching removal, the columnar protrusions 5 as shown in FIG.
8 and a recess 59 are formed.

As described above, in the semiconductor device of the present embodiment, the columnar projection 58 is formed in a portion corresponding to the transistor 52 inside the recess 58, and the semiconductor integrated circuit substrate 5 is formed.
When the substrate 1 and the silicon substrate 50 are bonded to each other, the tip of the columnar projection 58 is in contact with the transistor 52. Thereby, heat generated in the semiconductor integrated circuit substrate 51 and the transistor 52 is radiated from the silicon substrate 50 via the columnar protrusions 58, so that a semiconductor device having high heat dissipation can be obtained.

(Fifth Embodiment) FIG. 9 is a sectional view showing a semiconductor device according to a fifth embodiment of the present invention. In the semiconductor device of this embodiment, as shown in FIG. 9, a silicon substrate 601 of a semiconductor integrated circuit substrate 602 which is a semiconductor element
On the side surface, a transistor 603 as an active element and a wiring 604 electrically connected to the transistor 603 are formed. An external terminal 606 and a ground conductor 607a are formed on a surface of the semiconductor integrated circuit substrate 602 opposite to the transistor 603. Further, a through hole 605 is formed at a predetermined position of the semiconductor integrated circuit substrate 602, and the wiring 604 is formed by the through hole 604.
And the external terminal 606 are electrically connected. Further, a ground electrode (not shown) is formed on the surface of the semiconductor integrated circuit substrate 602 on the transistor 603 side. The ground electrode is formed on the semiconductor integrated circuit substrate 602 and has another through hole (not shown) different from the through hole 605.
Is electrically connected to the ground conductor 607a.

On the other hand, a concave portion 614 is formed on the surface of the silicon substrate 601 on the semiconductor integrated circuit substrate 602 side.
A columnar protrusion 608 is formed in a portion corresponding to the wiring 604 inside the concave portion 614. Silicon substrate 601
The external terminal 612 and the ground conductor 607b are formed on the surface of the side opposite to the concave portion 614 side. The external terminals 61 of the silicon substrate 601 are provided on the silicon substrate 601.
A through hole 611 penetrating the bottom surface of the recess 614 is formed from the surface where the second electrode 2 is formed, and one end of the through hole 611 is electrically connected to the external electrode 612.

The recess 61 of such a silicon substrate 601
The surface on the fourth side and the surface on the transistor 603 side of the semiconductor integrated circuit substrate 602 are bonded to each other via an adhesive 613 so that the transistor 603 is accommodated in the concave portion 614. When the semiconductor integrated circuit substrate 602 and the silicon substrate 601 are bonded to each other, a through hole 611 at the tip end surface of the protrusion 608, the side surface of the protrusion 608, and the bottom of the recess 614.
The conductive adhesive 601 is selectively adhered to the portion where is formed. Thereby, the tip of the columnar projection 608 and the wiring 6
04 are bonded via a conductive adhesive 610, and the wiring 604 and the external terminal 612 are electrically connected via the conductive adhesive 610.

Although not shown in FIG. 9, the grounding conductor 607a of the semiconductor integrated circuit board 602 and the grounding conductor 607b of the silicon substrate 601 may be connected to the columnar projection 608 inside the recess 614 as necessary. Conductive adhesive formed on the tip end surface and side surface of a columnar projection (not shown) different from the above, and a semiconductor integrated circuit substrate 602 and a silicon substrate 601
Are electrically connected to each other by through holes (not shown) formed in each of them. The atmosphere when the semiconductor integrated circuit substrate 602 and the silicon substrate 601 are bonded to each other is sealed inside the concave portion 614.

As a method of forming the conductive adhesive 610 of the semiconductor device, a columnar projection 608 is formed, and then photomask coating, mask exposure, metal deposition, and a lift-off method are performed. Protrusion 60
The conductive adhesive material 610 is selectively formed on the front end surface and side surface of the substrate 8, the bottom surface of the concave portion 614, and the like. The process of forming the through hole 611, the external terminal 612, and the ground conductor 607b is the same as the process of FIG. 2D for describing the method of manufacturing a semiconductor device in the first embodiment. After bonding the substrate 715, the semiconductor integrated circuit substrate 715 of the silicon substrate 712 is
A through hole or a ground conductor may be formed on the surface opposite to the side.

As described above, in the semiconductor device of the present embodiment, the tip end face and side face of the columnar projection 608 and the recess 61
Electrical connection is made between the semiconductor integrated circuit substrate 602 and the silicon substrate 601 via the conductive adhesive 610 formed on the bottom surface of the substrate 4. An integrated circuit is also formed on the silicon substrate 601 and the integrated circuit and the semiconductor integrated circuit substrate 6 are formed.
02 is electrically connected using the columnar projections in the recess 614, whereby a small-sized and high-density semiconductor device can be obtained.

In the third to fifth embodiments described above,
Although only two external terminals are shown in the figure, many external terminals may be formed for signal and bias.

As the adhesive used for the semiconductor device in the third to fifth embodiments, a metal such as AuSn or an organic material such as a photoresist is used.

[0079]

As described above, according to the present invention, a concave portion is formed on one surface of a substrate to which a semiconductor element is bonded, and the surface of the substrate on the concave side and the surface of the semiconductor element on which the active element is formed are formed. , Photoresist so that the active element fits into the recess
Because it is bonded via the bets, the inside of the recess, the atmosphere during bonding that is sealed, an active device is hermetically sealed by the recess. Accordingly, since it is not necessary to use a resin for hermetic sealing, there is an effect that a high-frequency characteristic is not deteriorated and a hermetically sealed semiconductor device is obtained.

Further, since a semiconductor is used as a material of the above-described substrate, the substrate and the semiconductor element are manufactured through a semiconductor manufacturing process with high processing accuracy, so that the surface accuracy of the substrate and the semiconductor element is good. . As a result, there is an effect that a semiconductor device with high airtightness can be obtained.

Further, by forming a conductive metal layer on the inner wall of the concave portion of the substrate, there is an effect that a semiconductor device that is electrically well shielded can be obtained.

According to the present invention, in a method of manufacturing a semiconductor device, a first semiconductor substrate having a plurality of recesses formed on one surface and a second semiconductor substrate having a plurality of active elements formed on one surface are provided. After bonding each active element so that it fits into the concave part corresponding to each active element, the semiconductor device is manufactured by dividing the chip, so that the active element is stored in the concave part and the hermetically sealed semiconductor device is inexpensive. This has the effect that it can be mass-produced.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a view illustrating a method of manufacturing the semiconductor device shown in FIG. 1;

FIG. 3 is a diagram illustrating a method for manufacturing a semiconductor device according to a second embodiment of the present invention.

FIG. 4 is a view illustrating a method of manufacturing a semiconductor device according to a second embodiment of the present invention.

FIG. 5 is a sectional view showing a semiconductor device according to a third embodiment of the present invention.

FIG. 6 is a sectional view showing a modification of the semiconductor device shown in FIG. 1;

FIG. 7 is a sectional view showing a modification of the semiconductor device shown in FIG. 6;

FIG. 8 is a sectional view showing a semiconductor device according to a fourth embodiment of the present invention.

FIG. 9 is a sectional view showing a semiconductor device according to a fifth embodiment of the present invention.

FIG. 10 is a sectional view showing a semiconductor device according to a conventional technique.

FIG. 11 is a sectional view showing a semiconductor device according to a conventional technique.

[Description of Signs] 1, 20, 40, 50, 601, 712, 812 Silicon substrate 2, 21, 51, 602, 715, 815 Semiconductor integrated circuit substrate 3, 26, 36, 46, 47, 56, 607a, 607
b Ground conductor 4 High-frequency electrode pad 5 Bias supply electrode pad 6, 28, 48, 59, 614, 713, 813 Concave portion 22, 52, 603 Transistor 23, 53, 604 Wiring 24, 54, 605, 611 Through hole 25, 55 , 606, 612 External terminal 27, 57, 613 Adhesive 58, 608 Columnar protrusion 610 Conductive adhesive 716 Scribe line 811 Sapphire substrate 814 First scribe line 816 Second scribe line

Claims (16)

(57) [Claims] 1. A semiconductor device having a semiconductor element having an active element formed on one surface and a substrate on which the semiconductor element is mounted, wherein a concave portion is formed on one surface of the substrate, and a surface of the substrate on the concave side is provided. A semiconductor device, wherein a surface of the semiconductor element on the active element side is bonded via a photoresist so that the active element fits in the recess. 2. The semiconductor device according to claim 1, wherein a semiconductor is used as a material of said substrate. 3. The semiconductor device according to claim 1, wherein said semiconductor element is an integrated circuit. 4. The semiconductor device according to claim 1, wherein a conductive metal layer is formed on at least a part of the surface of the semiconductor element or the substrate. 5. The semiconductor device according to claim 1, wherein a conductive metal layer is formed on an inner wall of the concave portion of the substrate. 6. An external terminal is formed on a surface of the semiconductor element opposite to the active element side, and a via hole or a via hole for electrically connecting the external terminal and the active element to the semiconductor element. The semiconductor device according to claim 1, wherein a through hole is formed. 7. A columnar projection is formed inside a recess of the substrate, and a tip of the columnar projection contacts the semiconductor element or an active element formed on the semiconductor element. 7. The semiconductor device according to any one of 6. 8. A columnar projection is formed inside a concave portion of the substrate, and a conductive layer is formed on a tip surface and a side surface of the columnar projection, and the semiconductor element and the substrate are connected to each other via the conductive layer. The semiconductor device according to any one of claims 1 to 7, wherein the semiconductor device is electrically connected between the semiconductor devices. 9. An external terminal is formed on a surface of the substrate opposite to the concave side, and the substrate is electrically connected to the conductive layer on a tip end surface and a side surface of the columnar protrusion. 9. A through-hole for connecting to a hole is formed.
3. The semiconductor device according to claim 1. 10. A step of forming a plurality of concave portions corresponding to each of a plurality of active elements formed on one surface of a second semiconductor substrate on one surface of a first semiconductor substrate; A step of bonding the first semiconductor substrate and the second semiconductor substrate so that an active element fits into a recess corresponding to each active element; and a step of bonding the first and second semiconductor substrates together. A method of manufacturing a semiconductor device, comprising at least a step of dividing into chips. 11. A step of forming, on one surface of a first semiconductor substrate, a plurality of recesses corresponding to each of a plurality of active elements formed on one surface of a second semiconductor substrate; A step of bonding the first semiconductor substrate and the second semiconductor substrate so that the active element fits into a recess corresponding to each active element; and a step of forming a through hole in the second semiconductor substrate. And a step of dividing the bonded first and second semiconductor substrates into chips in this order. 12. A sapphire substrate is attached to the other surface of the first semiconductor substrate before the step of forming the plurality of recesses on one surface of the first semiconductor substrate. After forming a plurality of recesses, a scribe line is formed on the surface of the first semiconductor substrate on the side of the recesses,
And when performing the step of bonding the second semiconductor substrate,
The first sapphire substrate and the scribe lines are used to see through the surface of the second semiconductor substrate on the active element side, and the first
The method of manufacturing a semiconductor device according to claim 10, wherein the semiconductor substrate is aligned with the second semiconductor substrate. 13. A step of bonding the first and second semiconductor substrates, wherein a metal layer is formed on a portion of the first semiconductor substrate on the concave side other than the concave, and The method of manufacturing a semiconductor device according to claim 10, wherein the first and second semiconductor substrates are bonded to each other via a substrate. 14. The method according to claim 13, further comprising forming a metal layer on an inner wall of the concave portion of the first semiconductor substrate. 15. An organic compound is formed in a portion other than the concave portion on the concave portion side surface of the first semiconductor substrate when performing the step of bonding the first and second semiconductor substrates. The method of manufacturing a semiconductor device according to claim 10, wherein the first and second semiconductor substrates are bonded to each other via a substrate. 16. When performing the step of bonding the first and second semiconductor substrates, a photoresist is formed on a portion other than the concave portion of the concave-side surface of the first semiconductor substrate;
The method of manufacturing a semiconductor device according to claim 10, wherein the first and second semiconductor substrates are bonded together via the photoresist.