JP7031178B2 - Semiconductor devices and their manufacturing methods - Google Patents

Description

The present invention relates to a semiconductor device in which a semiconductor device provided with a through electrode exposed from a semiconductor substrate at an end face is mounted with the end face on which the through electrode is formed facing the mounting substrate, and a method for manufacturing the same.

Conventionally, a semiconductor substrate having a front surface and a back surface and having a plurality of vias formed so as to extend from the front surface side to the back surface side is provided, and a part of the plurality of vias is divided in a plan view. , A semiconductor element exposed on an end surface, which is a surface connecting the front surface and the back surface, is known. Then, such a semiconductor element is mounted on the one surface via a bonding material provided in a part of the via exposed on the end surface in a state where the end surface thereof faces one surface of another circuit board. There are known semiconductor devices (hereinafter, such mounting is referred to as "end face mounting"). Examples of this type of semiconductor device include the invention described in Patent Document 1.

The semiconductor device described in Patent Document 1 has a first surface having a front and back relationship and another surface, and has a first semiconductor substrate on which a circuit such as an accelerometer is formed on one surface, and a second surface having a front surface and a back surface. It is configured to include a semiconductor element having the same semiconductor substrate. In the first semiconductor substrate, a plurality of vias extending from the other surface to the one surface side are formed, and one surface of the first semiconductor substrate is joined to the back surface of the second semiconductor substrate. The second semiconductor substrate has a plurality of vias extending from the front surface to the back surface side. The inner wall of these vias is formed with wiring electrically connected to the circuit of the first semiconductor substrate. In such a configuration, in the semiconductor device described in Patent Document 1, a part of the vias of the semiconductor element is divided into an arc shape when viewed from the normal direction with respect to one surface, and the inner wall surface of the part of the vias is divided. Is exposed on the end face side. Then, in this semiconductor device, the end surface of the semiconductor element faces one surface of another circuit board, and the end surface is mounted on one surface of another circuit board via a bonding material provided in the part of the via. ing.

When three semiconductor elements that can be mounted on the end face and are used as acceleration sensors are mounted on one circuit board so that the semiconductor elements can detect accelerations in each of the three axial directions orthogonal to each other, for example. It is a semiconductor device that can detect acceleration in each of the three axial directions.

Japanese Unexamined Patent Publication No. 2012-160733

By the way, the present inventors have studied that such end face mounting is performed by using a through silicon via formed by filling vias penetrating a semiconductor substrate with a conductive material such as a metal material, that is, a TSV. is doing. In this case, the TSV that is divided at the end face in a plan view, is exposed at the end face, and is used for the end face mounting (hereinafter referred to as "end face TSV") has a viewpoint of increasing the area of the end face mounting and improving the joining reliability. It is preferable that the diameter is larger than the diameter of other TSVs that are not exposed on the end face. However, when forming a plurality of TSVs having different diameters in this way, it is difficult to perform by a single plating method.

Specifically, when viewed from the normal direction with respect to the surface on which a plurality of vias are formed, a via having a small diameter (hereinafter referred to as "small diameter via") and a via having a large diameter (hereinafter referred to as "large diameter via") among the plurality of vias. We will consider the case of forming a TSV that fills each of the two types of vias (referred to as) by the plating method. At this time, the time required to form the TSV filling the large-diameter via (hereinafter referred to as "large-diameter TSV") is larger than the time required to form the TSV filling the small-diameter via (hereinafter referred to as "small-diameter TSV"). Is also long. Therefore, if an attempt is made to fill each of the small-diameter via and the large-diameter via with a single plating method, the plating will continue even after the small-diameter TSV is formed, and the small-diameter TSV is excessively formed so as to protrude from the semiconductor substrate. .. Further, since the method of forming the large-diameter TSV by the plating method requires time, the cost is higher than the case of forming only the small-diameter TSV by the plating method.

Here, the end face TSV is formed by filling the via with a metal material to form the TSV, and then performing a dicing cut so as to divide the TSV in a plan view. Therefore, the cross section of the TSV is on the end face side. It will be exposed. The end face TSV formed by such a process protrudes from the end face TSV side to the semiconductor substrate in a plan view because the metal material that constitutes the end face TSV is stretched when the metal material constituting the end face TSV is cut by the dicing blade. Protrusions, that is, burrs, may be formed. When such burrs are formed, the end face TSV is electrically connected to the semiconductor substrate and short-circuited, which causes a decrease in yield and a decrease in reliability.

The present invention has been made in view of the above points, and a semiconductor element having an end face TSV having a larger diameter than other TSVs and in which a short circuit in the end face TSV is suppressed is mounted on another mounting substrate. It is an object of the present invention to provide a semiconductor device mounted on an end face and a method for manufacturing the same.

In order to achieve the above object, the semiconductor device according to claim 1 has a mounting substrate (10) having one surface (10a), a front surface (20a), a back surface (20b), and an end surface (20c) connecting the front surface and the back surface. (20), and a semiconductor element (100) having a sensor unit (30) formed on the semiconductor substrate and outputting a signal according to a physical quantity. In such a configuration, the semiconductor substrate has a groove portion (21) formed on the end surface connecting the front surface and the back surface, and the groove portion is interposed with an insulating film (211) covering the inner wall surface of the groove portion and an insulating film. An end face electrode (212) having a solder is formed by filling the groove portion, and the semiconductor element is on one surface in a state where the surface of the end face on which the end face electrode is formed faces one side. It is mounted on the semiconductor substrate and electrically connected to the mounting substrate via the end face electrode . The insulating film is the first insulating film, and the semiconductor substrate has a through hole (22) connecting the front surface and the back surface. The through hole is filled with a second insulating film (221) that covers the inner wall surface of the through hole, and the through hole is filled with the through hole via the second insulating film, and the through electrode (222) is provided with solder. And are formed.

In this way, even when burrs are generated on the end face TSV by filling the groove formed on the end face and using a material having solder on the end face electrode, that is, the end face TSV exposed on the end face. The structure of the semiconductor element is such that burrs can be removed by heating. Further, by configuring the semiconductor element so that burrs can be removed from the end face TSV, it is possible to suppress the generation of leakage current of the semiconductor element in the end face TSV, and the yield and reliability are improved. Therefore, the yield and reliability of the semiconductor device using such a semiconductor element are improved.

The reference numerals in parentheses of each of the above means indicate an example of the correspondence with the specific means described in the embodiment described later.

It is a perspective view which shows the semiconductor device of 1st Embodiment. It is sectional drawing which shows the cross section at the time of cutting the semiconductor device of 1st Embodiment along the plane passing between II and II in FIG. It is a perspective view which shows the semiconductor element mounted on the end face. It is a figure which shows the manufacturing process of the semiconductor device of 1st Embodiment. It is a figure which shows the manufacturing process of the semiconductor device of 1st Embodiment following FIG. It is a plan view which shows the burr generated in the end face electrode and the removal thereof, (a) is the figure which shows right after the division of a semiconductor substrate, and (b) is the figure which shows after remelting and solidifying the end face electrode. It is a figure which shows the modification of the structure of the semiconductor element in the semiconductor device of 1st Embodiment, (a) is a perspective view, (b) is a sectional view of (a). It is a figure which shows the modification of the structure of the semiconductor element in the semiconductor device of 1st Embodiment, (a) is a perspective view, (b) is a sectional view of (a). It is a perspective view which shows the semiconductor device of 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following embodiments, the parts that are the same or equal to each other will be described with the same reference numerals.

(First Embodiment)
The semiconductor device S1 of the first embodiment will be described with reference to FIGS. 1 to 6. In FIGS. 1 and 2, in order to make the configuration easy to understand, configurations other than the mounting substrate 10, the semiconductor element 100, and the bonding material 40, which will be described later, are omitted. In FIGS. 1 and 3, in order to make the configuration easy to understand, the portion that cannot be seen from one direction when viewed from one direction is indicated by a broken line, and the insulating film formed on the surface 20a side of the semiconductor element 100 is shown. Is omitted.

As shown in FIG. 1 or 2, the semiconductor device S1 of the present embodiment includes a mounting substrate 10 and a semiconductor element 100, and the semiconductor element 100 is mounted on one surface 10a of the mounting substrate 10. There is.

In the present embodiment, the mounting substrate 10 is a plate-shaped substrate having one side 10a made of, for example, a glass epoxy resin. The mounting board 10 may include circuit wiring (not shown), an electrode pad, an IC (abbreviation of Integrated Circuit) chip (not shown) for controlling the semiconductor element 100, and the like.

In the present embodiment, as shown in FIG. 1 or 2, the semiconductor element 100 includes a semiconductor substrate 20 and a sensor portion 30 formed on the semiconductor substrate 20, and is mounted via a bonding material 40. It is mounted on one side 10a of the substrate 10. Specifically, as shown in FIG. 3, the semiconductor element 100 is placed on the one surface 10a with the mounting surface 20ca on which the end surface electrode 212 is formed of the end surface 20c facing the one surface 10a side of the mounting substrate 10. It is mounted on the end face.

The semiconductor substrate 20 is made of, for example, silicon, and in the present embodiment, as shown in FIG. 3, a quadrangular plate having a front surface 20a, a back surface 20b on the opposite side thereof, and an end surface 20c connecting the front surface 20a and the back surface 20b. It is said to be in the shape. As shown in FIG. 2, the semiconductor substrate 20 is formed with a groove portion 21 connecting the front surface 20a and the back surface 20b and a through hole 22.

In the present embodiment, as shown in FIG. 3, the groove portion 21 has an arc shape when viewed from the normal direction with respect to the back surface 20b (hereinafter referred to as “back surface normal direction”), and two groove portions 21 are provided on the end surface 20c. .. The inner wall surface of the groove portion 21 is covered with a first insulating film 211 made of an insulating material such as SiO ₂ . As shown in FIG. 3, the groove portion 21 is filled with the end face electrode 212 via the first insulating film 211. The groove portion 21 is not limited to the arc shape, but may have a trapezoidal shape, a polygonal shape, or the like, may be provided with a taper, or may have another shape.

The end face electrode 212 is made of, for example, a conductive material having solder. The end face electrode 212 is formed as a result of forming a through hole, an insulating film covering the inner wall surface thereof, and an electrode for filling the through hole through the insulating film on the semiconductor substrate 20, and then dividing the end face by dicing cut or the like. In 20c, the cross section in the extending direction is exposed from the semiconductor substrate 20. This detail will be described in the manufacturing process described later.

As shown in FIG. 1, the end face electrode 212 mounts the semiconductor element 100 on one side 10a of the mounting substrate 10 via the bonding material 40, and is arranged so that the exposed cross section faces the one side 10a. In other words, the semiconductor element 100 is arranged so that the mounting surface 20ca on which the end surface electrode 212 is formed faces the one surface 10a side of the end surface 20c. In the present embodiment, the end face electrode 212 is electrically connected to the mounting substrate 10 via the bonding material 40.

As shown in FIG. 3, it is preferable that the maximum width of the end face electrode 212 is larger than the maximum width of the through electrode 222 described later when viewed from the back surface normal direction. More specifically, when viewed from the back normal direction, the width of the mounting surface 20ca of the end face electrode 212 is preferably larger than the maximum width of the through electrode 222. This is to increase the reliability in the bonding of the semiconductor element 100 by widening the exposed area on the mounting surface 20ca of the end face electrode 212, that is, widening the bonding area.

The widths of the end face electrode 212 and the through silicon via 222 are arbitrary and are appropriately adjusted. Further, in the present embodiment, an example in which two groove portions 21, the first insulating film 211, and the end face electrode 212 are formed is described, but the present invention is not limited to this, and the numbers thereof may be changed as appropriate. good.

As shown in FIG. 3, the through holes 22 have a circular shape and are provided inside three through holes 22 inside the outer region of the semiconductor substrate 20 when viewed from the back surface normal direction. The inner wall surface of the through hole 22 is covered with a second insulating film 221 made of an insulating material such as SiO ₂ . As shown in FIG. 2, the through hole 22 is filled with the through electrode 222 via the second insulating film 221.

Like the end face electrode 212, the through electrode 222 is made of, for example, a conductive material having solder. In the present embodiment, the through electrode 222 is electrically connected to the end face electrode 212 and the sensor portion 30 via a circuit wiring (not shown) provided on the front surface 20a side or the back surface 20b side.

The through hole 22 is not limited to a circular shape, but may have an elliptical shape, a polygonal shape, or the like, may be provided with a taper, or may have another shape. Further, in the present embodiment, an example in which three through holes 22, a second insulating film 221 and a through electrode 222 are formed is described, but the present invention is not limited to this, and the numbers thereof may be appropriately changed. ..

The sensor unit 30 outputs signals according to physical quantities such as acceleration, angular velocity, and magnetism, and is formed by a known semiconductor process. In the present embodiment, the sensor unit 30 has a circuit configuration for detecting an angular velocity, that is, a gyro sensor, and outputs a signal corresponding to the angular velocity in the surface normal direction.

The sensor unit 30 may be, for example, an acceleration sensor, a gyro sensor, a geomagnetic sensor, or the like, but since the configuration thereof is known, detailed description of the configuration and the like will be omitted in the present specification. Further, in the present embodiment, the sensor unit 30 is formed on the front surface 20a side of the semiconductor substrate 20, but the present invention is not limited to this, and the sensor unit 30 may be formed on the back surface 20b side.

The bonding material 40 is composed of a conductive material having solder, for example, a solder or a mixed material of solder particles and an epoxy resin (so-called resin reinforced solder), and electrically connects the mounting substrate 10 and the end face electrode 212. Is connected.

The above is the configuration of the semiconductor device S1 of the present embodiment. The semiconductor device S1 having such a configuration functions as a gyro sensor or the like as a whole.

Next, the manufacturing method of the semiconductor device S1 will be described with reference to FIGS. 4 and 5. Of the steps of forming the semiconductor element 100, steps other than the formation of the end face electrode 212 and the through electrode 222 are known, and therefore, they will be briefly described here.

First, as shown in FIG. 4A, a semiconductor substrate 20 made of silicon and having a front surface 20a and a back surface 20b is prepared. Then, as shown in FIG. 4B, the sensor unit 30 is formed on the surface 20a side by a normal semiconductor process. After that, for example, an insulating film made of an insulating material such as SiO ₂ is formed on the surface 20a side by a method such as CVD (abbreviation of Chemical Vapor Deposition). Then, for example, a wiring layer (not shown) electrically connected to the sensor unit 30 is formed by a vacuum film forming method such as sputtering or a vapor deposition method, and the wiring layer is covered with an insulating film by the same method as described above. As a result, as shown in FIG. 4C, a surface insulating film 20A that covers the surface 20a side and has a wiring layer (not shown) is formed.

After forming the front insulating film 20A, as shown in FIG. 4D, for example, by dry etching using a mask (not shown), the front surface 20a and the back surface 20b are connected and formed into a circle when viewed from the back surface normal direction. A plurality of trenches 21A and through holes 22 which are columnar holes are formed.

The trench 21A will later become the groove portion 21, and the diameter of the trench 21A as seen from the back surface normal direction is larger than the diameter of the through hole 22. Further, the trench 21A and the through hole 22 are deep enough not to penetrate the surface insulating film 20A and to expose the wiring layer (not shown) formed in the surface insulating film 20A to the back surface 20b side.

After forming the trench 21A and the through hole 22, the insulating film is formed of an insulating material such as SiO ₂ by a method such as CVD. Specifically, as shown in FIG. 4 (e), the back surface insulating film 20B covering the back surface 20b, the inner wall insulating film 21B covering the inner wall surface of the trench 21A, and the second insulating film 221 covering the inner wall surface of the through hole 22. To form.

As a result of the above-mentioned forming of the insulating film, an insulating film is also formed at the bottoms of the trench 21A and the through hole 22 when viewed from the back normal direction, and covers the wiring layer in the front insulating film 20A. The one formed on the bottom is removed by dry etching or the like. As a result, the state shown in FIG. 4 (e) is obtained.

Next, for example, a seed layer (not shown) as a base for applying solder, which will be described later, is formed on the back surface 20b side by sputtering. Specifically, the seed layer has a structure in which, for example, thin films Ti and Cu are laminated in this order, and the back surface insulating film 20B, the inner wall insulating film 21B, the second insulating film 221 and the bottom and through holes in the trench 21A. It will cover the bottom of 22. Then, in a vacuum or depressurized environment, as shown in FIG. 5A, after applying molten solder to the back surface 20b side of the semiconductor substrate 20, the semiconductor substrate 20 is pressurized from the back surface 20b side to form an electrode. Form layer 20C. Specifically, the electrode layer 21C that fills the trench 21A via the inner wall insulating film 21B and the electrode layer 22C that fills the through hole 22 via the second insulating film 221 are formed. Then, as shown in FIG. 5B, polishing is performed to remove an excess seed layer on the back surface 20b side and a part of the electrode layer 20C due to soldering.

By applying the melted solder in a vacuum or reduced pressure environment, it is possible to suppress the formation of voids in the electrode layers 21C and 22C which will later become the end face electrode 212 or the through silicon via 222. Further, by forming the electrode layers 21C and 22C collectively by applying the melted solder, the electrode layers 21C and 22C having different maximum widths when viewed from the surface normal direction can be formed in a shorter time and lower than the plating method. It can be formed at cost.

Subsequently, as shown in FIG. 5 (c), the electrode layer 21C is divided into cross sections shown by the alternate long and short dash lines in FIG. 5 (c) by, for example, dicing cut, and the cross section of the electrode layer 21C in the extending direction is a semiconductor substrate. Expose from 20. As a result, the semiconductor element 100 including the groove portion 21, the first insulating film 211, and the end face electrode 212 is formed.

When the solder constituting the electrode layer 21C is expanded by dicing cut to form burrs by dividing the electrode layer 21C, for example, the semiconductor substrate 20 is heated to melt the electrode layer 21C and then melted. The burrs are removed by solidifying the electrode layer 21C again. More on this later.

Subsequently, as shown in FIG. 5D, the semiconductor element 100 is directed toward the one side 10a side of the mounting surface 20ca on which the mounting surface 20ca on which the end face electrode 212 is provided is separately prepared, via, for example, a bonding material 40 made of solder. To be installed.

The semiconductor device S1 can be manufactured by the above steps. The above manufacturing method is merely an example, and is not limited to the above example, and may be appropriately modified.

Next, the formation of burrs and the removal thereof in the end face electrode 212 will be described with reference to FIG. In FIG. 6, in order to make it easy to understand how the burrs generated on the end face electrode 212 are removed, the sensor portion 30 and the surface insulating film 20A of the semiconductor element 100 are omitted.

The end face electrode 212 is formed, for example, by dicing cut along the direction D indicated by the arrow in FIG. 6A, and its cross section is exposed from the semiconductor substrate 20 at the end face 20c. At this time, as the solder constituting the end face electrode 212 is extended by the blade used for dicing cut, as shown in FIG. 6A, protrusions 212a, so-called burrs, that come into contact with the exposed end face 20c of the semiconductor substrate 20 are formed. May be formed. When the protrusion 212a is formed, the end face electrode 212 is electrically connected to the semiconductor substrate 20 and is in a short-circuited state. When the end face electrode 212 is short-circuited with the semiconductor substrate 20 on the end face 20c, the yield and reliability of the semiconductor element 100 are lowered, which causes the reliability of the semiconductor device S1 to be lowered.

In a conventional semiconductor device (hereinafter, simply referred to as "conventional semiconductor device") in which a through electrode is made of a metal material such as Cu, when such a burr occurs when an attempt is made to form an end face electrode, the countermeasure is taken. Was difficult. As a result of diligent studies, the present inventors have formed an end face electrode 212 from a conductive material having solder, and a semiconductor using a semiconductor element having a configuration in which even if burrs occur, they can be easily removed. He came to invent the device.

Specifically, even when the protrusion 212a as shown in FIG. 6A is formed, since the end face electrode 212 is made of solder, the semiconductor substrate 20 is heated to melt the protrusion 212a. After that, the protrusion 212a can be removed by solidifying it again. More specifically, for example, it is allowed to stand on a hot plate at 230 ° C. for about 30 seconds in a nitrogen atmosphere to dissolve the end face electrode 212. Then, the solder constituting the end face electrode 212 gathers in the groove 21 due to surface tension, and as shown in FIG. 6B, the solder forming the protrusion 212a returns to the inside of the groove 21. After the state shown in FIG. 6B is reached, the end face electrode 212 without burrs can be formed by solidifying the solder that has been cooled and melted again.

The semiconductor substrate 20 exposed on the mounting surface 20ca formed by the dicing cut has poor solder wetting, so that molten solder is unlikely to remain. Further, the heating temperature, time, and heating atmosphere described above are merely examples, and may be appropriately changed as long as they are above the melting point of the solder and can melt the protrusions 212a. The heating atmosphere is preferably an atmosphere in which the solder does not oxidize or is difficult to oxidize, for example, a nitrogen atmosphere or a hydrogen atmosphere, from the viewpoint of facilitating the mounting process of the semiconductor element 100 by solder reflow or the like.

In this way, by forming the end face electrode 212 with a conductive material having solder, even if burrs occur, the end face electrode 212 is heated and melted, and then cooled and solidified. Burrs can be easily removed. That is, it is possible to obtain a semiconductor element 100 in which a short circuit does not occur in the end face electrode 212, and by mounting on the end face using this, a conventional highly reliable semiconductor device can be obtained.

Further, in the conventional semiconductor device, solder or the like is arranged so as to surround the portion in the vicinity of one surface 10a of the surfaces adjacent to the mounting surface of the semiconductor element when viewed from the normal direction with respect to one surface 10a of the mounting substrate 10, and the semiconductor element is arranged. Even if it was mounted or end face mounted, the joint area was small. In the former case, that is, when the solder is connected to the mounting board 10 by using the adjacent surface of the mounting surface, the stress generated in the solder due to the vibration is large, which may cause a decrease in reliability. In the latter case, the stress generated in the solder due to vibration is smaller than that of the former due to the end face mounting, but the joint area of the conventional semiconductor device is small, so that the reliability cannot be said to be sufficient.

On the other hand, the semiconductor device S1 of the present embodiment has a configuration in which the semiconductor element 100 is mounted on the end face, the stress generated in the solder due to vibration is small, and the cross-sectional area of the end face electrode 212, that is, the joint area is large. It will be a semiconductor device with higher reliability than before.
(Modification 1 of the first embodiment)
In the first embodiment, an example in which the semiconductor element 100 is configured by using one semiconductor substrate 20 has been described, but the semiconductor element 100 is not limited to the above example, and as shown in FIG. 7, two semiconductors are used. Those composed of the substrates 20 and 50 may be used.

Specifically, in the semiconductor element 100 in the present modification 1, as shown in FIGS. 7A and 7B, the semiconductor substrate 20 is used as the first semiconductor substrate 20, and the first semiconductor substrate 20 and the second semiconductor substrate are used. It differs from the above-mentioned first embodiment in that the structure is such that 50 and 50 are laminated. In this modification 1, this difference will be mainly described.

FIG. 7A is a perspective view of the semiconductor element 100 composed of the semiconductor substrates 20 and 50. FIG. 7 (b) is a cross-sectional view of a semiconductor device on which the semiconductor element 100 shown in FIG. 7 (a) is cut by a plane passing between VIIB and VIIB in FIG. 7 (a).

As shown in FIG. 7B, in the semiconductor element 100 of the present modification 1, the sensor unit 30 is formed on the second semiconductor substrate 50, the second semiconductor substrate 50 functions as a device substrate, and the first semiconductor The substrate 20 is configured to function as a cap substrate.

The second semiconductor substrate 50 is made of, for example, silicon, and as shown in FIG. 7A, has a front surface 50a and another surface 50b, and a side surface 50c connecting the one surface 50a and the other surface 50b. It has a quadrangular plate shape. The second semiconductor substrate 50 has a sensor portion 30 formed on the other surface 50b side and is in contact with the surface 20a side of the first semiconductor substrate 20 on the other surface 50b side. As shown in FIG. 7A, the second semiconductor substrate 50 has the same plane dimensions as the first semiconductor substrate 20 when viewed from the surface normal direction, and the outer region thereof is the outer region of the first semiconductor substrate 20. It is arranged so as to overlap with.

As shown in FIG. 7A, the first semiconductor substrate 20 is described above except that the sensor portion 30 is not formed and the end face electrode 212 is exposed on both the front surface 20a side and the back surface 20b side. It has the same configuration as the first embodiment. A recess, that is, a cavity may be formed on the surface 20a side of the first semiconductor substrate 20 to cover the sensor portion 30 formed on the second semiconductor substrate 50. Further, in this modification, the through electrode and the end face electrode are manufactured only on the first semiconductor substrate 20, but the through electrode and the end face electrode may be manufactured on the second semiconductor substrate 50, or may be manufactured on both substrates. good.

In the present modification 1, the end face electrode 212 of the first semiconductor substrate 20 is exposed from the first semiconductor substrate 20 on the back surface 20b side, but is covered with the surface insulating film 20A on the front surface 20a side. The end face electrode 212 is not directly electrically connected to the other surface 50b of the second semiconductor substrate 50.

The semiconductor element 100 has a surface 50ca facing the same side as the mounting surface 20ca among the side surface 50c of the mounting surface 20ca on which the end face electrode 212 of the first semiconductor substrate 20 is formed and the side surface 50c of the second semiconductor substrate 50, and one surface of the mounting substrate 10. It is mounted on the end face toward the 10a side.

In the case of the present modification 1, it is preferable that a so-called resin reinforced solder is used as the bonding material 40. As a result, the surface 50ca of the second semiconductor substrate 50 is bonded to the mounting substrate 10 via the resin in the bonding material 40, and the mounting surface 20ca of the first semiconductor substrate 20 is bonded to the mounting surface 20ca of the bonding material 40 via solder. Since it is joined to the mounting board 10, alignment is easy. When the resin reinforced solder is not used as the bonding material 40, for example, an adhesive made of resin is used for the second semiconductor substrate 50 side, and a conductive bonding material made of solder is used for the first semiconductor substrate 20 side.

Also in the first modification, the semiconductor device is more reliable than the conventional one, as in the first embodiment.
(Modification 2 of the first embodiment)
As shown in FIG. 8, the semiconductor element 100 may be composed of two semiconductor substrates 20 and 50, and may have a configuration in which electrodes exposed from the semiconductor substrate are formed on both mounting surfaces.

In the second modification, the end face electrode 212 of the first semiconductor substrate 20 is also exposed on the surface 20a side, and the second groove portion 51, the third insulating film 511, and the side electrode 512 are formed on the side surface 50c of the second semiconductor substrate 50. It differs from the above-mentioned modification 1 in that the semiconductor element 100 is used. In this modification 2, this difference will be mainly described.

FIG. 8A is a perspective view of the semiconductor element 100 composed of the semiconductor substrates 20 and 50. FIG. 8 (b) is a cross-sectional view of a semiconductor device on which the semiconductor element 100 shown in FIG. 8 (a) is cut by a plane passing between VIIIB and VIIIB in FIG. 8 (a).

As shown in FIG. 8, in the first semiconductor substrate 20, the end face electrodes 212 are exposed from the first semiconductor substrate 20 on both the front surface 20a side and the back surface 20b side, and are electrically connected to the side electrode 512 of the second semiconductor substrate 50. It is connected to the.

As shown in FIG. 8, the second semiconductor substrate 50 has a second groove portion 51 having an arc shape when viewed from the surface normal direction on the side surface 50c. The inner wall surface of the second groove 51 is covered with the third insulating film 511, and is filled with the side electrode 512 made of a conductive material having solder via the third insulating film 511.

As shown in FIG. 8A, the side electrode 512 is formed in the same number as the end face electrodes 212, and has the same cross-sectional area as the end face electrodes 212 when viewed from the surface normal direction. ing. The side electrode 512 is arranged so as to be connected to the end face electrode 212.

In the semiconductor element 100, the mounting surface 20ca on which the end face electrode 212 is formed and the mounting surface 50ca on which the side electrode 512 is formed are mounted on the end faces of the mounting substrate 10 toward one surface 10a.

The second groove portion 51, the third insulating film 511, and the side electrode 512 are formed by the same process as the manufacturing process of the end face electrode 212 described in the first embodiment. Further, the semiconductor element 100 can be manufactured by aligning the first semiconductor substrate 20 and the second semiconductor substrate 50 and joining these semiconductor substrates by an arbitrary semiconductor process.

Also in the second modification, the semiconductor device is more reliable than the conventional one, as in the first embodiment.

(Second Embodiment)
The semiconductor device S2 of the second embodiment will be described with reference to FIG. In FIG. 9, the axial direction on the left and right sides of the paper surface of FIG. 9 is the X axis, the axial direction on the plane of the mounting substrate 10 and orthogonal to the X direction is the Y axis, and the axial direction orthogonal to the XY plane is Z. It is the axis. Further, in FIG. 9, in order to make the configuration easy to understand, the bonding material for connecting the semiconductor element 100 and the control IC 60 described later to the mounting board 10, the circuit wiring formed on the mounting board 10, and the like are omitted.

As shown in FIG. 9, the semiconductor device S2 of the present embodiment includes a mounting substrate 10, three semiconductor elements mounted on one surface 10a of the mounting substrate 10, and a control IC 60 for controlling the semiconductor element 100. It differs from the first embodiment in that it is configured. In this embodiment, this difference will be mainly described.

As shown in FIG. 9, the control IC 60 is mounted on one surface 10a of the mounting substrate 10 via a bonding material (not shown) such as solder, and a plurality of electrode pads 61 are formed on the opposite surface of the one surface 10a. ing. The control IC 60 is electrically connected to the mounting board 10 via a wire 62 or the like, and is also electrically connected to the semiconductor element 100 mounted on the end face via the mounting board 10.

The three semiconductor elements 100 mounted on one surface 10a of the mounting board 10 are different in the mounted state, but all have the same structure. As shown in FIG. 9, each of the three semiconductor elements 100 is arranged so that the surface normal direction is along the X-axis, the Y-axis, and the Z-axis, and corresponds to the physical quantity in the X-axis, the Y-axis, and the Z-axis. It is arranged to output a signal.

Specifically, in the present embodiment, the semiconductor element 100 that outputs signals according to physical quantities on the X-axis and the Y-axis is mounted on the end face of the mounting substrate 10 via a bonding material (not shown). The semiconductor element 100 that outputs a signal corresponding to a physical quantity on the Z axis is not mounted on an end face, and a surface different from the end face or the side surface is directed toward one surface 10a side of the mounting substrate 10, and the different surface is not shown. It is mounted on the mounting board 10 via a material.

With such a structure, the semiconductor device S2 can detect the angular velocities in the directions of the X-axis, the Y-axis, and the Z-axis. Further, by configuring the semiconductor device S2 that detects the physical quantity in the triaxial direction by using three semiconductor elements 100 having the same structure, the semiconductor device has less variation in the characteristics of the signal output in the axial direction.

Specifically, for example, a semiconductor device equipped with one semiconductor element having a structure for detecting a physical quantity in the three-axis direction will be examined. In this case, the semiconductor element has a structure including three sensor units, but since all the sensor units that detect physical quantities in the respective axial directions cannot have the same structure, the X-axis, Y-axis, and Z-axis The signal output characteristics in the above will vary. Therefore, in a semiconductor device equipped with one semiconductor element that detects a physical quantity in the three-axis direction, the characteristics of the signal output in the axial direction vary.

On the other hand, since the semiconductor device S2 of the present embodiment has a configuration in which three semiconductor elements 100 having the same structure are mounted, variations in signal output characteristics in each axial direction can be suppressed. Become.

Further, the semiconductor device S2 of the present embodiment uses the semiconductor element 100 having the same structure, although the mounted states of the semiconductor elements 100 on the mounting substrate 10 are different. Therefore, the manufacturing cost of the semiconductor element 100 can be reduced by mass production, and the effect of becoming a low-cost semiconductor device is also expected.

Further, in the semiconductor element having a structure in which one element detects each physical quantity in the three-axis direction, when a defect occurs in the sensor portion of one axis, the sensor portion of the other two axes does not have a defect. However, the yield tends to be low because the entire semiconductor element becomes defective. On the other hand, the semiconductor element 100 that outputs a signal corresponding to the physical quantity of only one axis has a higher yield than the semiconductor element provided with the sensor unit for three axes. From this point of view, the semiconductor device S2 is expected to have the effect of lowering the cost than the conventional one.

In the present embodiment, the semiconductor element 100 is a gyro sensor that detects an angular velocity, but it may be an acceleration sensor, a magnetic sensor, or another sensor.

(Other embodiments)
The semiconductor device and the manufacturing method thereof shown in each of the above-described embodiments show an example of the present invention, and are not limited to the above-mentioned embodiments, but are described in the scope of claims. It can be changed as appropriate within.

For example, in each of the above embodiments, an example in which the semiconductor element 100 is mounted on the mounting substrate 10 via the bonding material 40 has been described, but the semiconductor element 100 uses solder constituting the end face electrode 212 and the side electrode 512. It may be mounted directly on the mounting board 10.

In the first and second modifications of the first embodiment, the semiconductor element 100 has described an example in which the device substrate and the cap substrate are laminated and the through electrode is not formed on the semiconductor substrate used as the device substrate. Not limited to this, through electrodes may also be formed on the device substrate. The semiconductor element 100 used for end face mounting may have an end face electrode 212 or a side electrode 512 formed therein, and the arrangement of the through electrodes and the sensor unit 30 may be appropriately changed.

Specifically, the semiconductor element 100 composed of the device substrate and the cap substrate may have a configuration in which the end face electrodes are formed only on the device substrate, or a configuration in which the end face electrodes are formed only on the cap substrate. You may. Further, the semiconductor element 100 may be composed of a device substrate and a cap substrate, and may have a configuration in which end face electrodes are formed on both substrates. Then, while the through electrode 222 is formed on the first semiconductor substrate 20 on which the end face electrode is formed, the through electrode may be formed on the second semiconductor substrate 50, if necessary.

10 Mounting board 20, 50 Semiconductor board 20c End face 21, 51 Groove 212 End face electrode 22 Through hole 222 Through electrode 50c Side surface

Claims (12)

A mounting board (10) having one surface (10a) and
A semiconductor substrate (20) having a front surface (20a), a back surface (20b), and an end surface (20c) connecting the front surface and the back surface, and a sensor unit (30) formed on the semiconductor substrate and outputting a signal according to a physical quantity. ), And a semiconductor element (100).
In the semiconductor substrate, a groove portion (21) connecting the front surface and the back surface is formed on the end surface.
In the groove portion, an insulating film (211) that covers the inner wall surface of the groove portion and an end face electrode (212) that fills the groove portion via the insulating film and has solder are formed.
The semiconductor element is mounted on the one side of the end face in a state where the surface on which the end face electrode is formed faces the one side, and is electrically connected to the mounting substrate via the end face electrode. Has been
The insulating film is the first insulating film.
The semiconductor substrate is formed with a through hole (22) connecting the front surface and the back surface.
The through hole is provided with a second insulating film (221) that covers the inner wall surface of the through hole, and a through electrode (222) that is filled with the through hole via the second insulating film and has solder. Is formed into a semiconductor device. A mounting board (10) having one surface (10a) and
A semiconductor element (30) having a semiconductor substrate (20) having a front surface (20a), a back surface (20b), and an end surface (20c) connecting the front surface and the back surface, and a sensor unit (30) for outputting a signal according to a physical quantity. 100) and
In the semiconductor substrate, a groove portion (21) connecting the front surface and the back surface is formed on the end surface.
The groove portion is formed with an insulating film (211) that covers the inner wall surface of the groove portion and an end face electrode (212) that fills the groove portion via the insulating film and has solder.
The semiconductor element is mounted on the one side of the end face in a state where the surface on which the end face electrode is formed faces the one side, and is electrically connected to the mounting substrate via the end face electrode. Has been
The insulating film is the first insulating film.
The semiconductor substrate is formed with a through hole (22) connecting the front surface and the back surface.
The through hole is provided with a second insulating film (221) that covers the inner wall surface of the through hole, and a through electrode (222) that is filled with the through hole via the second insulating film and has solder. Is formed,
The semiconductor substrate is a first semiconductor substrate, and the semiconductor substrate is a first semiconductor substrate.
The semiconductor element further includes a second semiconductor substrate (50).
The second semiconductor substrate is laminated on the first semiconductor substrate, and is laminated on the first semiconductor substrate.
The sensor unit is a semiconductor device formed on the first semiconductor substrate or the second semiconductor substrate. The second semiconductor substrate has one surface (50a) and another surface (50b) that are in a front-to-back relationship, and also has a side surface (50c) that connects the one surface and the other surface.
A second groove portion (51) connecting the one surface and the other surface is formed on the side surface, with the groove portion as the first groove portion.
In the second groove portion, the insulating film covering the inner wall surface of the first groove portion is used as the first insulating film, and the inner wall surface of the second groove portion is covered with the third insulating film (511) and has solder. A side electrode (512) that fills the second groove portion is formed via the third insulating film.
The surface of the side surface on which the side surface electrode is formed is arranged so as to face the one side together with the surface of the end surface on which the end surface electrode is formed.
The semiconductor device according to claim 2 , wherein the semiconductor element is mounted on the one surface via the end face electrode and the side surface electrode. In the semiconductor element, one of the first semiconductor substrate and the second semiconductor substrate is a sensor chip provided with the sensor unit, and the other is a cap.
The semiconductor device according to claim 2 or 3 , wherein the sensor unit is arranged on a surface of the sensor chip facing the cap and sealed by the cap. The semiconductor device according to claim 4 , wherein the first semiconductor substrate is a cap. The semiconductor device according to any one of claims 1 to 5 , wherein the semiconductor element is mounted on one surface of the semiconductor device via a bonding material (40) composed of solder and resin. The semiconductor device according to any one of claims 1 to 6, wherein the maximum width of the end face electrode and the maximum width of the through electrode are different from each other when viewed from the normal direction with respect to the surface. A mounting board (10) having one surface (10a) and
A semiconductor substrate (20) having a front surface (20a), a back surface (20b), and an end surface (20c) connecting the front surface and the back surface, and a sensor unit (30) formed on the semiconductor substrate and outputting a signal according to a physical quantity. ), A semiconductor device (100), and the like.
In the semiconductor substrate, a groove portion (21) connecting the front surface and the back surface is formed on the end surface.
The groove portion is formed with an insulating film (211) that covers the inner wall surface of the groove portion and an end face electrode (212) that fills the groove portion via the insulating film and has solder.
The semiconductor element is mounted on the one side of the end face in a state where the surface on which the end face electrode is formed faces the one side, and is electrically connected to the mounting substrate via the end face electrode. Has been
The semiconductor element is a semiconductor device mounted on one surface of the semiconductor device via a bonding material (40) composed of solder and resin. The physical quantity is any one of acceleration, angular velocity, and magnetism.
The semiconductor device according to any one of claims 1 to 8, wherein the semiconductor element functions as any one of an acceleration sensor, an angular velocity sensor, and a geomagnetic sensor. The method for manufacturing a semiconductor device according to any one of claims 1 to 9.
Preparing the mounting board and
It extends from the front surface or the back surface to the other surface, and covers a plurality of trenches (21A, 22) having different maximum width dimensions when viewed from the normal direction with respect to the front surface or the back surface, and the inner wall surface of the plurality of trenches. To prepare the semiconductor substrate on which the insulating film (21B, 221) is formed, and to prepare the semiconductor substrate.
After preparing the semiconductor substrate, the plurality of trenches are filled with molten solder to solidify the solder.
Part of the plurality of trenches filled with the solder is divided to form the end face electrode to which the solder is exposed on the end face.
Forming the semiconductor element using the semiconductor substrate on which the end face electrode is formed, and
Manufacture of the semiconductor device including mounting the semiconductor element on the one surface of the mounting substrate with the surface of the end surface on which the end face electrode is formed facing the one surface side of the mounting substrate. Method. The tenth aspect of filling the plurality of trenches with the molten solder is performed by applying the molten solder in a vacuum and then pressurizing the semiconductor substrate to which the molten solder is applied. The method for manufacturing a semiconductor device according to the description. The method for manufacturing a semiconductor device according to claim 10 or 11, wherein after forming the end face electrode, the end face electrode is melted by heating and the melted end face electrode is solidified again.

Images