JP2010114288A - Method of manufacturing semiconductor device, semiconductor device, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To part into individual chip unit bodies while preventing an element formation part from large chipping and cracking, etc., even in the case that a stuck substrate is used. <P>SOLUTION: A semiconductor is manufactured through a first parting stage of parting a first substrate of a stuck substrate, constituted by sticking a first substrate 11 and a second substrate 12 together, from the side of the first substrate 11 along a scribe line set for the first substrate 11, a second parting stage of parting the second substrate 12 of the stuck substrate from the side of the second substrate 12 along a scribe line set for the second substrate 12, and an expanding stage of expanding and separating the stuck substrate having been processed through the first parting stage and second parting stage. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a semiconductor device, a semiconductor device, and an electronic apparatus including the semiconductor device.

In recent years, with the progress of miniaturization manufacturing technology on substrates, so-called micro electro-mechanical devices (hereinafter referred to as “MEMS”) called micromachines and small devices incorporating the MEMS have attracted attention. .
Specifically, an inertial sensor that detects, for example, angular velocity and acceleration is known as one of functional elements using the MEMS structure. These include capacitance changes caused by the movement of a vibrator supported so as to be displaced by an external inertia force, and resistance changes of a piezoresistive element or a piezoelectric element formed on an elastic support that holds the vibrator. The inertial force is measured using it.
Such a functional element using the MEMS structure can be formed by using a semiconductor process, and has a feature that integration with other semiconductor devices is easy.

By the way, in a semiconductor process, after forming a large number of semiconductor devices on a semiconductor substrate, the semiconductor substrate is generally diced and divided into individual devices (chips) to be separated into individual pieces. .
Dividing into single chips is usually performed using a dicing blade. That is, the semiconductor substrate is divided into single chips by performing dicing in a lump using a dicing blade from the substrate surface along a preset scribe line.
On the other hand, recently, a metal film is formed on both sides of the scribe line in order to suppress chipping or cracking when dicing all at once (for example, refer to Patent Document 1), or a coating is formed on the substrate surface. -It has been proposed to apply a tailing agent (see, for example, Patent Document 2). It has also been proposed to perform dicing using an energy beam instead of a dicing blade (see, for example, Patent Documents 3 and 4).

Japanese Patent No. 2052789 Japanese Patent No. 3221394 Japanese Patent No. 3509985 JP 2007-83309 A

  However, in the above-described conventional technology, the following problems may occur when a semiconductor device using a bonded substrate formed by bonding a plurality of substrates is divided into individual chips. .

  For example, in a MEMS structure, an SOI (Silicon on insulator) substrate is often used. The SOI substrate is a bonded substrate in which an active layer made of silicon is stacked on a support layer. Specifically, two wafer substrates each having an oxide film (for example, silicon in an amorphous state) and a wafer substrate having no oxide film formed thereon are bonded to each other, It is constructed by scraping the surface. In the SOI substrate having such a configuration, the crystal state (crystal orientation) of each substrate differs on the bonding surface.

For this reason, when dicing is performed on a bonded substrate such as an SOI substrate from one side of the substrate at a time as in the related art described above, the propagation direction of cracks on the bonded surface of each substrate is uniform. It will not be like. That is, it is considered that due to the difference in crystal orientation of each substrate on the bonding surface, chipping, cracks, and the like become larger than when the respective crystal orientations are aligned. This is due to the difference in crystal orientation. Therefore, when a metal film or a coating agent is used as in Patent Documents 1 and 2, energy is used instead of a dicing blade as in Patent Documents 3 and 4. It can also happen when using a beam.
Therefore, when the conventional technique is used to separate the bonded substrates, chips and cracks on the bonded surfaces of the substrates may adversely affect the function of the element to be formed. In particular, in the case of a device in which the inside of a structure needs to maintain an airtight state like a MEMS structure, it is considered that the airtight state cannot be maintained. Further, in the case where the wiring exists so as to cross the scribe line in the intermediate layer of the bonded substrate, the wiring is naturally cut by dicing.

  Accordingly, the present invention provides a semiconductor device that can be singulated into single chips while preventing large chips or cracks from entering the element formation portion even when a bonded substrate is used. An object is to provide a manufacturing method, a semiconductor device, and an electronic apparatus.

  The present invention provides a method for manufacturing a semiconductor device devised to achieve the above object, wherein the first substrate and the second substrate are bonded to the bonded substrate formed by bonding the first substrate and the second substrate. From the second substrate side with respect to the bonded substrate, the first dividing step of dividing the first substrate along the scribe line set for the first substrate, and the second substrate. A second dividing step of dividing the second substrate along the set scribe line; and an expanding step of expanding and separating the bonded substrate after the first dividing step and the second dividing step. .

  According to the method for manufacturing a semiconductor device in the above procedure, by separating each of the first substrate and the second substrate from both sides of the bonded substrate and then performing expansion separation, the chip is separated into individual pieces. Will do. That is, the first substrate and the second substrate are divided separately and are not collectively performed across the bonding surfaces of these substrates. Therefore, even if the crystal orientations of the first substrate and the second substrate are different, the effect (for example, the propagation direction of cracks on the bonding surface of each substrate does not become uniform) affects the single chip. There is no end to individualization.

  According to the present invention, even if the crystal orientations of the first substrate and the second substrate constituting the bonded substrate are different, it is possible to singulate into single chips while eliminating the influence. In other words, even if the crystal orientation is different between the first substrate and the second substrate, and the propagation direction of cracks on the bonding surface of each substrate does not become uniform, the element formation part is chipped or cracked due to the influence. It can be prevented from occurring. Therefore, for example, in a device in which the inside of the structure needs to be maintained in an airtight state, such as a MEMS structure, it becomes possible to avoid that the airtight state cannot be maintained. In addition, since the first substrate and the second substrate are separated separately and independently, for example, even when wiring exists across the scribe line in the intermediate layer of the bonded substrate, the wiring is protected. It becomes possible to do. Furthermore, by cutting each substrate separately and independently, for example, when a dicing blade is used for dividing, the blade depth is reduced because the cutting depth is smaller than dividing each substrate at once. Can be shortened, and as a result, the blade blade can be expected to be reduced in breakage.

  Hereinafter, a semiconductor device manufacturing method, a semiconductor device, and an electronic apparatus according to the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory view schematically showing an outline of a method for manufacturing a semiconductor device according to the present invention.
As shown in the figure, the semiconductor device manufacturing method described here constitutes one step of a semiconductor process, and a plurality of semiconductor devices 2 formed on a semiconductor substrate 1 are divided into single devices (chips). It is for singulation.
The semiconductor substrate 1 is a bonded substrate configured by bonding a plurality of substrates. As the bonded substrate, for example, an SOI substrate used for a functional element using a MEMS structure can be given. However, it is not limited to the SOI substrate.

<First Embodiment>
Here, first, a first embodiment of the present invention will be described.
In the first embodiment, the semiconductor substrate 1 to be divided is an example in which the first substrate and the second substrate are bonded to each other, that is, the two substrates are bonded to each other. To

[Description of Manufacturing Method of Semiconductor Device]
FIG. 2 is an explanatory diagram showing a specific example of the method of manufacturing the semiconductor device according to the first embodiment.
As shown in the figure, in the first embodiment, the semiconductor substrate 1 is configured by bonding a first substrate 11 and a second substrate 12 together. Examples of such a semiconductor substrate (hereinafter also referred to as “bonded substrate”) 1 include an SOI substrate having a thermal oxide film (not shown) sandwiched therebetween. In the case of an SOI substrate, the first substrate 11 corresponds to an active layer constituting the SOI substrate, and the second substrate 12 corresponds to a support layer constituting the SOI substrate. The first substrate 11 is formed with a thickness of about 10 to 50 μm, for example, and the second substrate 12 is formed with a thickness of about 400 μm, for example.
However, the bonded substrate 1 is not limited to an SOI substrate, and is configured by appropriately combining any one of a silicon substrate, a GaAs substrate, a glass substrate, and the like as the first substrate 11 and the second substrate 12. There may be.
The bonding of the first substrate 11 and the second substrate 12 may be performed by using a well-known technique such as Au-Au bonding method, Au-Sn bonding metal bonding, room temperature bonding, or the like. . Moreover, when one side is formed with the glass substrate, it is also possible to utilize, for example, bonding by an anodic bonding method.

In the case where such a bonded substrate 1 is divided into single chips, first, as shown in FIG. 2A, a first dividing step for dividing the first substrate 11 is performed. In the first dividing step, the first substrate 11 in the bonded substrate 1 is moved from the first substrate 11 side with the dicing tape 13 applied to the surface of the bonded substrate 1 on the second substrate 12 side. Cut along the scribe line set for one substrate 11.

  At this time, the scribe line set for the first substrate 11 may be the same as the scribe line set for the second substrate 12. That is, the portion corresponding to the extension line in the substrate thickness direction with respect to the scribe line set for the second substrate 12 may be the scribe line for the first substrate 11. However, it may be set separately from the scribe line for the second substrate 12.

  Further, it is conceivable to divide the first substrate 11 by weakening the first substrate 11. Here, “weakening” refers to a technique for dividing a substrate, and means that the substrate is in a fragile state that can be divided. Specifically, it is conceivable that the first substrate 11 is made fragile by performing any one of removal, cutting, and modification.

The weakening by the removal may be performed by, for example, an etching process on the first substrate 11. That is, the first substrate 11 can be divided by partially removing the forming material of the first substrate 11 along the scribe line by etching the first substrate 11.
For example, the etching process may be performed by dry etching using a DRIE (Deep Reactive Ion Etching) method. In that case, first, a mask pattern for removing a scribe line is formed on the surface of the first substrate 11, and dry etching of the DRIE method is performed to weaken the first substrate 11.
However, the etching process is not limited to dry etching, and for example, chemical dry etching or wet etching can be used. In that case, for example, tetramethylammonium hydroxide (TMAH) or a potassium hydroxide (KOH) aqueous solution may be used as an etchant for wet etching.

  For example, the weakening by cutting may be performed by dicing the first substrate 11. However, the dicing at this time is half-cut dicing. That is, the first substrate 11 is subjected to half-cut dicing using a dicing blade, and the forming material of the first substrate 11 is partially cut along the scribe line in the thickness direction, The first substrate 11 is brought into a state where it can be divided. The depth of the half-cut dicing is not particularly limited, and is set to an amount that can divide the first substrate 11 by expanding separation described later in consideration of the thickness of the first substrate 11 and the forming material. do it.

  The weakening by the modification may be performed by, for example, laser processing for the first substrate 11. In other words, the first substrate 11 is irradiated with laser light with the focal point being aligned, and a modified region (for example, a region where the crystal structure is divided) along the scribe line in the first substrate 11. By forming the first substrate 11, the first substrate 11 can be divided. As such a laser processing, a processing called stealth dicing is known. In the laser processing, if a focal point is set near the surface of the first substrate 11, there is a problem of particle generation due to ablation on the surface of the first substrate 11. Is preferred.

  After weakening the 1st board | substrate 11 by execution of such a 1st cutting process, as shown in FIG.2 (b), the 2nd cutting process which cuts the 2nd board | substrate 12 is then performed. In the second dividing step, the second substrate 12 in the bonded substrate 1 is moved from the second substrate 12 side to the first substrate with the dicing tape 14 applied to the surface of the bonded substrate 1 on the first substrate 11 side. Cut along the scribe line set for the two substrates 12.

  Since the thickness of the second substrate 12 is different from that of the first substrate 11, it may be considered that the second substrate 12 is cut or modified.

  Dividing by cutting may be performed by dicing on the second substrate 12 as in the first dividing step. However, the dicing at this time is half-cut dicing. That is, half-cut dicing using a dicing blade is performed on the second substrate 12, and the forming material of the first substrate 11 is partially cut along the scribe line in the thickness direction. The depth of the half-cut dicing is not particularly limited, but may be set to an amount that can divide the second substrate 12 by expanding separation described later. Specifically, for example, with respect to the second substrate 12 having a thickness of about 400 μm, the remaining dicing amount on the second substrate 12 may be about 20 to 100 μm.

  What is necessary is just to perform the division | segmentation by modification | reformation similarly to a 1st parting process. That is, by forming a modified region along the scribe line in the second substrate 12 by laser processing called stealth dicing, the second substrate 12 can be divided.

  Thereafter, as shown in FIG. 2C, the expanding process is performed on the bonded substrate 1 after the first dividing process and the second dividing process. In the expanding step, expanding separation is performed on the bonded substrate 1. Here, the expansion separation means that a force is applied in the direction along the surface of the bonded substrate 1 to divide the bonded substrate 1 along the scribe lines for the first substrate 11 and the second substrate 12. Say. In addition, since a well-known technique should just be utilized about the technique of an expand separation, the detailed description is abbreviate | omitted here.

  After the expansion separation, removal from the dicing tape 14 is performed. Removal from the dicing tape 14 can be easily performed by curing the adhesive layer of the dicing tape 14 by, for example, irradiation with ultraviolet light.

  After passing through the first dividing step, the second dividing step and the expanding step as described above, the bonded substrate 1 is subjected to scribe lines for the first substrate 11 and the second substrate 12 as shown in FIG. The device (chip) to be divided is divided into individual pieces.

FIG. 3 is an explanatory diagram illustrating a specific example of a scribe line according to the first embodiment.
As already described, the scribe line for the first substrate 11 (see the broken line in the figure) and the scribe line for the second substrate 12 (see the dashed line in the figure) may be the same as each other. . Specifically, it is conceivable to set each scribe line in a lattice shape as shown in the figure. It is conceivable that the size of the lattice is set so that, for example, the width of one lattice is about 10 to 100 μm.

[Description of Semiconductor Device]
FIG. 4 is an external view showing a specific example of the semiconductor device according to the first embodiment.
As shown in the figure, the semiconductor device manufactured through the above-described procedure is configured by bonding the first substrate 11 and the second substrate 12, and the plane is divided into quadrilaterals, for example. What was comprised by being separated is mentioned.

  As described above, this semiconductor device is divided into pieces by performing expand separation after dividing the first substrate 11 and the second substrate 12 from both sides of the bonded substrate 1. Has been. That is, even if the first substrate 11 and the second substrate 12 are bonded together, the first substrate 11 and the second substrate 12 are divided separately and independently. , 12 are not performed at once across the bonding surfaces. Therefore, even if the crystal orientations of the first substrate 11 and the second substrate 12 are different, the influence (for example, the propagation direction of cracks on the bonding surfaces of the substrates 11 and 12 is not uniform). However, the semiconductor device is not divided into individual pieces.

Further, in manufacturing the semiconductor device having such a configuration, if the weakening of the first substrate 11 is performed by the etching process in the first dividing step, the weakening can be appropriately and flexibly performed. That is, according to the etching process, it is possible to easily remove only the first substrate 11 without affecting the second substrate 12 by selecting a substrate forming material, an etching gas, an etching solution, or the like. As a result, vulnerability can be appropriately optimized. In addition, since the scribe line can be specified by using the photolithography technique, it is possible to secure the flexibility of weakening. Such weakening due to the etching process is very effective when applied when the thickness of the first substrate 11 is sufficiently thinner than the second substrate 12.
On the other hand, in the first dividing step, even when weakening the first substrate 11 is performed using modification by laser processing, the laser beam irradiation position becomes the position of the scribe line, so that the scribe line can be set freely. A sufficient degree can be secured. Therefore, it is possible to flexibly cope with the weakness of the first substrate 11. Moreover, the width of the scribe line can be made narrower in the case of laser processing than in the case of dicing or the like. Therefore, it is very suitable for effectively utilizing the limited space on the semiconductor substrate 1.
In the second dividing step, if the second substrate 12 is divided by half-cut dicing that stops halfway in the thickness direction of the second substrate 12, the influence of the division may affect the first substrate 11. Disappear. In other words, the division can be made appropriate, which is very suitable for preventing chipping, cracking, and the like when the chip is divided into individual pieces.

<Second Embodiment>
Next, a second embodiment of the present invention will be described. Here, differences from the above-described first embodiment will be mainly described.
In the second embodiment, a semiconductor substrate 1 to be divided (see FIG. 1) is configured to include a third substrate in addition to the first substrate and the second substrate, that is, three substrates. The case where it is what is bonded together is given as an example.

[Description of Manufacturing Method of Semiconductor Device]
FIG. 5 is an explanatory diagram showing a specific example of a method for manufacturing a semiconductor device according to the second embodiment.

In the second embodiment, as in the case of the first embodiment, the first dividing step is performed on the bonded substrate 1 configured by bonding the first substrate 11 and the second substrate 12. Thus, the first substrate 11 is weakened. And after a 1st parting process, as shown to Fig.5 (a), the 3rd board | substrate 15 is bonded together to the surface by the side of the 1st board | substrate 11 which performed weakening.
As the third substrate 15, it is possible to use any one of a silicon substrate, a GaAs substrate, a glass substrate, and the like. In addition, the third substrate 15 may be bonded by using a well-known technique such as Au-Au bonding method, Au-Sn bonding metal bonding, room temperature bonding, or the like. Moreover, when one side is formed with the glass substrate, it is also possible to utilize, for example, bonding by an anodic bonding method.

  After the third substrate 15 is bonded, as shown in FIG. 5B, the second substrate 12 is divided with the dicing tape 16 attached to the surface on the third substrate 15 side. Perform the cutting process. That is, as in the case of the first embodiment, the second substrate 12 is divided along the scribe line.

  Thereafter, as shown in FIG. 5C, a third dividing step of dividing the third substrate 15 is performed in a state where the dicing tape 17 is applied to the divided surface of the second substrate 12 side. In the third dividing step, the third substrate 15 is divided along the scribe line set for the third substrate 15 from the third substrate 15 side. The scribe line set for the third substrate 15 may be the same as the scribe line set for the first substrate 11 and the second substrate 12. Moreover, what is necessary is just to perform the division | segmentation at this time similarly to the case of a 2nd parting process. However, when the division at this time is performed by dicing, full-cut dicing is performed to a depth reaching the first substrate 11 instead of half-cut dicing.

  After passing through such a first parting process, a second parting process, and a third parting process, an expanding process is performed as shown in FIG. That is, as in the case of the first embodiment, the laminate including the first substrate 11, the second substrate 12, and the third substrate 15 is divided along the scribe line.

  After passing through each process as described above, the laminate composed of the first substrate 11, the second substrate 12 and the third substrate 15 becomes the first substrate 11, the second substrate 12 and the second substrate 12, as shown in FIG. The device (chip) divided by the scribe line for the third substrate 15 is divided into individual pieces.

FIG. 6 is an explanatory diagram showing a specific example of the scribe line in the second embodiment.
As already described, the scribe line for the first substrate 11 (see the broken line in the figure) and the scribe line for the second substrate 12 and the third substrate 15 (see the dashed line in the figure) are respectively. May be the same as each other. Specifically, it is conceivable to set each scribe line in a lattice shape as shown in the figure. It is conceivable that the size of the lattice is set so that, for example, the width of one lattice is about 10 to 100 μm.

[Description of Semiconductor Device]
FIG. 7 is an external view showing a specific example of the semiconductor device according to the second embodiment.
As shown in the figure, the semiconductor device manufactured through the procedure described above is configured by bonding the first substrate 11, the second substrate 12, and the third substrate 15, and the plane is, for example, a quadrilateral. What was comprised by being divided | segmented into pieces is mentioned.

  As described above, the semiconductor device is divided into individual pieces by performing expand separation after dividing each of the first substrate 11, the second substrate 12, and the third substrate 15 from each side. Has been. That is, even if the first substrate 11, the second substrate 12, and the third substrate 15 are bonded to each other, the division for each of the substrates 11, 12, and 15 is performed separately. The process is not performed collectively across the bonding surfaces of the substrates 11, 12, and 15. Therefore, even if the crystal orientations of the substrates 11, 12, and 15 are different from each other, the influence thereof (for example, the propagation direction of cracks on the bonding surfaces of the substrates 11, 12, and 15 does not become uniform). The semiconductor device is not separated into individual pieces.

  In the second embodiment, it is preferable that the first dividing step is performed by using etching or laser processing, or the second dividing step is performed by half-cut dicing. This is exactly the same as in the first embodiment.

<Third Embodiment>
Next, a third embodiment of the present invention will be described. Here, differences from the above-described first or second embodiment will be mainly described.
In the third embodiment, a semiconductor substrate 1 (see FIG. 1) to be divided includes a third substrate in addition to the first substrate and the second substrate, that is, three substrates. The case where it is what is bonded together is given as an example.

[Description of Manufacturing Method of Semiconductor Device]
FIG. 8 is an explanatory view showing a specific example of the method of manufacturing a semiconductor device according to the third embodiment.

  Also in the third embodiment, as in the case of the first embodiment, the first dividing step is performed on the bonded substrate 1 configured by bonding the first substrate 11 and the second substrate 12 together. Then, the first substrate 11 is weakened. At this time, a part of the first substrate 11 that is an unnecessary portion (see arrow A in FIG. 8D) is used to facilitate the separation of the expansion in the expanding step described later (see arrow A in FIG. 8D). Etching is preferably performed so as to be lower by several μm than the bonding surface with the third substrate 21.

And after a 1st parting process, as shown to Fig.8 (a), the 3rd board | substrate bonding process which bonds the 3rd board | substrate 21 to the surface by the side of the 1st board | substrate 11 which performed weakening is performed.
As the third substrate 21, it is possible to use any one of a silicon substrate, a GaAs substrate, a glass substrate, and the like.
However, unlike the case of the second embodiment described above, the wiring layer 22 is formed on the third substrate 21 on the surface to be bonded to the first substrate 11. It is conceivable that the wiring layer 22 is formed by forming an aluminum alloy containing aluminum, copper, silicon or the like as a main composition by sputtering, for example.
The bonding of the third substrate 21 may be performed using a well-known technique such as Au-Au bonding method, Au-Sn bonding metal bonding, room temperature bonding, or the like. Moreover, when one side is formed with the glass substrate, it is also possible to utilize, for example, bonding by an anodic bonding method.
In bonding the third substrate 21, in the third substrate bonding step, since the wiring layer 22 is formed on the third substrate 21, the weakened first substrate 11 side surface is Bonding is performed on the wiring formation surface of the third substrate 21. Further, since the wiring layer 22 is formed on the third substrate 21, the bonding of the third substrate 21 is caused by the position where the wiring layer 22 is formed on the third substrate 21 and the weakening on the first substrate 11. Are performed in a state where the positions are aligned with each other.

  After the third substrate bonding step, subsequently, as shown in FIG. 8B, the second substrate 12 is divided with the dicing tape 23 applied to the surface on the third substrate 21 side. Perform the cutting process. That is, as in the case of the first embodiment, the second substrate 12 is divided along the scribe line.

  Thereafter, as shown in FIG. 8C, a third dividing step of dividing the third substrate 21 is performed in a state where the dicing tape 24 is stuck on the divided second substrate 12 side. In the third dividing step, the third substrate 21 is divided along the scribe line set for the third substrate 21 from the third substrate 21 side. It is assumed that the scribe line for the third substrate 21 is set at a position different from the scribe lines for the first substrate 11 and the second substrate 12, unlike the case of the second embodiment described above. Moreover, what is necessary is just to perform the division | segmentation at this time similarly to the case of a 2nd parting process. However, when the division at this time is performed by dicing, full-cut dicing is performed to a depth reaching the first substrate 11 instead of half-cut dicing.

  After such a first dividing step, a third substrate bonding step, a second dividing step, and a third dividing step, an expanding step is performed as shown in FIG. That is, the expanded separation is performed on the laminated body including the first substrate 11, the second substrate 12, and the third substrate 21. However, at this time, the scribe line for the third substrate 21 is set at a position different from the scribe line for the first substrate 11 and the second substrate 12. Therefore, the first substrate 11, the second substrate 12, and the third substrate 21 are formed so that part of the first substrate 11 and the second substrate 12 becomes unnecessary portions when the expand separation is performed (see arrow A in the figure). The laminated body which consists of will be parted.

  After going through each of the steps as described above, the laminate composed of the first substrate 11, the second substrate 12, and the third substrate 21 becomes the first substrate 11, the second substrate 12, and the second substrate 12 as shown in FIG. The device is divided into individual devices (chips) separated by the scribe lines for the third substrate 21 (see arrow B in the figure).

FIG. 9 is an explanatory diagram illustrating a specific example of a scribe line according to the third embodiment.
In the third embodiment, as already described, the scribe line for the third substrate 21 (see the two-dot chain line in the drawing) is the scribe line for the first substrate 11 (see the broken line in the drawing). And it is set in a position different from the scribe line (refer to the alternate long and short dash line in the figure) for the second substrate 12. Specifically, each scribe line is set so that the region where the scribe line for the first substrate 11 and the second substrate 12 is included in the region where the scribe line for the third substrate 21 is formed. ing.
Note that the scribe lines for the first substrate 11 and the second substrate 12 may be set so that each is the same and the width of the region is about 10 to 100 μm, as shown in FIG. 9A. It is done. However, as shown in FIG. 9B, it is not necessarily the same as long as it defines the same region.

[Description of Semiconductor Device]
FIG. 10 is an external view showing a specific example of the semiconductor device according to the third embodiment.
As shown in the figure, the semiconductor device manufactured through the procedure described above is configured by bonding the first substrate 11, the second substrate 12, and the third substrate 21. It is in a state where it is separated.
As described above, the wiring layer 22 is formed on the third substrate 21, and a part of the first substrate 11 and the second substrate 12 becomes unnecessary portions during the expansion separation. Therefore, in the semiconductor device obtained in the third embodiment, a part of the wiring layer 22 formed on the third substrate 21 is exposed around the portion formed by the first substrate 11 and the second substrate 12. It becomes the composition.

  This semiconductor device is configured to be separated into individual pieces by performing expansion separation after dividing each of the first substrate 11, the second substrate 12 and the third substrate 21 from the respective surfaces. That is, even if the first substrate 11, the second substrate 12, and the third substrate 21 are bonded to each other, the division for each of the substrates 11, 12, and 21 is performed separately. It is not performed collectively across the bonding surfaces of the substrates 11, 12, and 21. Therefore, even if the crystal orientations of the substrates 11, 12, and 21 are different, the influence thereof (for example, the propagation direction of cracks on the bonding surfaces of the substrates 11, 12, and 21 is not uniform). The semiconductor device is not separated into individual pieces.

Further, in the semiconductor device obtained in the third embodiment, since the division for each of the substrates 11, 12, and 21 is performed separately and independently, even if the wiring layer 22 exists, the wiring layer 22 is present. Can be avoided in advance, and the wiring layer 22 can be appropriately protected.
This is the same not only when the wiring layer 22 is present but also when the hollow structure is present. That is, for example, even when the hollow structure constituting the MEMS structure is formed inside the bonded laminated body, the chip can be singulated without destroying the constituent walls of the hollow structure.

Furthermore, even if the semiconductor device obtained in the third embodiment has a structure in which a part of the wiring layer 22 is exposed, it is easy to realize the thinning.
For example, with respect to a conventional general laminated structure, it is proposed that a plurality of substrates are bonded with a spacer interposed therebetween, and half-cut dicing is repeated to expose the inner electrode pad to the outside. (For example, refer to JP 2007-208230 A.). However, in such a laminated structure, since each substrate is bonded together with a spacer interposed therebetween, the thickness is increased and there is a possibility that the thickness cannot be reduced. Further, when the spacer is bonded with an epoxy resin, there is a possibility that a corrosion reaction or a reduction reaction of the element portion may occur due to the influence of outgas. Furthermore, in the case of an element that detects displacement in the substrate bonding direction, there is a possibility that variations in displacement detection sensitivity may increase due to variations in the thickness of the epoxy resin (in the order of several tens of micrometers).
However, according to the semiconductor device obtained in the third embodiment, since the substrates 11, 12, and 21 are directly bonded together, the overall thickness does not increase more than necessary. Further, since the substrates 11, 12, and 21 are bonded by anodic bonding, Si bonding, metal bonding, etc., there is no influence of outgas, and an airtight sealed state can be maintained. Furthermore, the thickness variation in the bonding direction can be set to the order of several nanometers (substrate surface roughness level). For these reasons, the semiconductor device obtained in the third embodiment can be easily and appropriately reduced in thickness as compared with the prior art.

  In the third embodiment, the first dividing step is preferably performed using etching or laser processing, or the second dividing step is preferably performed by half-cut dicing. This is exactly the same as in the first embodiment.

<Fourth embodiment>
Next, a fourth embodiment of the present invention will be described. Note that here also, the differences from the first to third embodiments described above will be mainly described.
In the fourth embodiment, a semiconductor substrate 1 (see FIG. 1) to be divided is configured to include a fourth substrate in addition to the first substrate, the second substrate, and the third substrate, that is, four. An example is a case in which a plurality of substrates are bonded together.

[Description of Manufacturing Method of Semiconductor Device]
FIG. 11 is an explanatory diagram showing a specific example of a method for manufacturing a semiconductor device according to the fourth embodiment.

  Also in the fourth embodiment, as in the case of the third embodiment, the first dividing step is performed on the bonded substrate 1 composed of the first substrate 11 and the second substrate 12, and the first One board 11 is weakened. Then, after the first dividing step, as shown in FIG. 11A, a wiring layer 22 is formed on the weakened first substrate 11 side by executing the third substrate bonding step. The third substrate 21 is bonded to the wiring forming surface.

After the third substrate bonding step, subsequently, as shown in FIG. 11B, a fourth substrate bonding step is performed in which the fourth substrate 25 is bonded to the surface on the second substrate 12 side.
As the fourth substrate 25, it is conceivable to use any one of a silicon substrate, a GaAs substrate, a glass substrate, and the like. In addition, the fourth substrate 25 may be bonded using a known technique such as Au-Au bonding, metal bonding using Au-Sn bonding, or room temperature bonding. Moreover, when one side is formed with the glass substrate, it is also possible to utilize, for example, bonding by an anodic bonding method.

  After the fourth substrate bonding step, subsequently, as shown in FIG. 11 (c), the second cutting that divides the second substrate 12 with the dicing tape 26 applied to the surface on the third substrate 15 side. Execute the process. However, the fourth substrate 25 is bonded to the surface on the second substrate 12 side. Therefore, in the second dividing step, the second substrate 12 and the fourth substrate 25 are divided along the scribe line set for the second substrate 12. That is, with respect to the laminate formed by bonding the first substrate 11, the second substrate 12, the third substrate 21, and the fourth substrate 25, from the fourth substrate 25 side, The fourth substrate 25 and the fourth substrate 25 are divided.

  Thereafter, as shown in FIG. 11 (d), a third dividing step of dividing the third substrate 21 is performed in a state where the dicing tape 27 is stuck on the divided surface of the fourth substrate 25. In the third dividing step, the third substrate 21 is divided along the scribe line set for the third substrate 21 from the third substrate 21 side. The scribe line for the third substrate 21 is set at a position different from the scribe lines for the first substrate 11, the second substrate 12, and the fourth substrate 25, as in the case of the third embodiment described above. Shall. Further, when the division at this time is performed by dicing, full-cut dicing is performed to a depth reaching the first substrate 11 instead of half-cut dicing.

  After passing through the first dividing step, the third substrate bonding step, the fourth substrate bonding step, the second dividing step, and the third dividing step, the expanding step is performed as shown in FIG. To do. That is, the expanded separation is performed on the laminated body including the first substrate 11, the second substrate 12, the third substrate 21, and the fourth substrate 25. However, at this time, the scribe line for the third substrate 21 is set at a position different from the scribe lines for the first substrate 11, the second substrate 12, and the fourth substrate 25. Therefore, when expanded separation is performed, the first substrate 11, the second substrate 12, and the first substrate 11, the second substrate 12, and the fourth substrate 25 become unnecessary portions (see arrow C in the figure). The laminated body composed of the third substrate 21 and the fourth substrate 25 is divided.

  After passing through each process as described above, the laminated body composed of the first substrate 11, the second substrate 12, the third substrate 21 and the fourth substrate 25 is, as shown in FIG. The second substrate 12, the third substrate 21, and the fourth substrate 25 are divided into individual devices (chips) divided by scribe lines (see arrow D in the figure).

FIG. 12 is an explanatory diagram showing a specific example of the scribe line in the fourth embodiment.
In the fourth embodiment, as already described, the scribe line for the third substrate 21 (see the two-dot chain line in the drawing) is the scribe line for the first substrate 11 (see the broken line in the drawing). In addition, the second substrate 12 and the fourth substrate 25 are set at positions different from the scribe lines (see the alternate long and short dash line in the drawing). Specifically, each region is formed so that scribe lines for the first substrate 11, the second substrate 12, and the fourth substrate 25 are included in the regions where the scribe lines for the third substrate 21 are formed. A scribe line is set.
Note that the scribe lines for the first substrate 11, the second substrate 12, and the fourth substrate 25 are the same as each other and the width of the region is about 10 to 100 μm, as shown in FIG. It is possible to set. However, as shown in FIG. 12B, it is not necessarily the same as long as it defines the same region.

[Description of Semiconductor Device]
FIG. 13 is an external view showing a specific example of the semiconductor device according to the fourth embodiment.
As shown in the figure, the semiconductor device manufactured through the procedure described above is configured by bonding the first substrate 11, the second substrate 12, the third substrate 21, and the fourth substrate 25, and by expanding separation. This is a state where individual chips are separated.
As described above, the wiring layer 22 is formed on the third substrate 21, and part of the first substrate 11, the second substrate 12, and the fourth substrate 25 becomes unnecessary portions during the expansion separation. . Therefore, the semiconductor device obtained in the fourth embodiment has one wiring layer 22 formed on the third substrate 21 around the portion formed by the first substrate 11, the second substrate 12, and the fourth substrate 25. The part is exposed.

  This semiconductor device is configured as a single piece by performing expand separation after dividing each of the first substrate 11, the second substrate 12, the third substrate 21, and the fourth substrate 25 from each side. Has been. That is, even if the first substrate 11, the second substrate 12, the third substrate 21, and the fourth substrate 25 are bonded together, at least the divisions for the substrates 11, 12, and 21 are independent of each other. And is not performed collectively across the bonding surfaces of these substrates 11, 12, and 21. Therefore, even if the crystal orientations of the substrates 11, 12, and 21 are different, the influence thereof (for example, the propagation direction of cracks on the bonding surfaces of the substrates 11, 12, and 21 is not uniform). The semiconductor device is not separated into individual pieces.

Further, in the semiconductor device obtained in the fourth embodiment, at least each of the substrates 11, 12, and 21 is divided and independently performed. Therefore, even if the wiring layer 22 exists, the wiring layer 22 is present. 22 can be prevented from being cut, and appropriate protection can be achieved.
This is the same not only when the wiring layer 22 is present but also when the hollow structure is present. That is, for example, even when the hollow structure constituting the MEMS structure is formed inside the bonded laminated body, the chip can be singulated without destroying the constituent walls of the hollow structure.

Furthermore, even if the semiconductor device obtained in the fourth embodiment has a structure in which a part of the wiring layer 22 is exposed, it is easy to realize the thinning. This is exactly the same as in the case of the third embodiment described above.
Also in the fourth embodiment, the first dividing step is preferably performed using etching or laser processing, or the second dividing step is preferably performed by half-cut dicing. This is exactly the same as in the first embodiment.

[Description of application example of semiconductor device]
As a specific example of the semiconductor device having the above configuration, an inertial sensor that detects acceleration, angular velocity, and the like can be given.
For example, as an inertial sensor for detecting acceleration, one based on the basic structure and operation principle described below is known. In an inertial sensor, a mass portion formed on a substrate is displaced by receiving a force proportional to acceleration, whereby a deflection occurs in an elastic support. On the upper surface side of this elastic support, 12 displacement detection means (total 24 locations) are formed. The displacement detection means corresponds to two orthogonal detection axes (X axis and Y axis) on the elastic support and one detection axis (Z axis) perpendicular to the elastic support. It is configured using a Wheatstone bridge circuit composed of a piezoresistive element or a piezoelectric element. Therefore, when a deflection occurs in the elastic support, the displacement detector detects the acceleration in the triaxial direction (see, for example, JP-A-2003-172745).
FIG. 14 is a signal block diagram showing the operating principle of the inertial sensor that detects the inertial force. As shown in the figure, for detecting the inertial force, an amplifier, a temperature correction circuit, and a filter for amplifying the signal obtained by each inertial sensor are provided for each one system.
FIG. 15 is a flowchart showing an example of the inertial force detection process. In the inertial force detection process of the illustrated example, when the inertial sensor detects “acceleration”, it is determined in the “threshold range” whether the detected acceleration is a detectable acceleration set in advance in the inertial sensor. In this determination unit, if the detected acceleration is within the threshold range, it is determined as “yes”, and a predetermined process is executed. On the other hand, when the determination unit determines that the detected acceleration is “no” that is not within the threshold range, the inertial sensor detects the acceleration again.
FIG. 16 is a schematic configuration perspective view showing a specific example of a SIP (System in a Package) including an inertial sensor. The SIP shown in FIG. 1 includes an inertial sensor 100, a memory chip 81, and an ASIC (Application Specific Integrated Circuit) chip 91, to which the present invention is applied, in one package 71. Note that the SIP shown here is only a specific example, and any semiconductor chip other than the above chips can be mounted. Even if the semiconductor chip and the inertial sensor 100 are combined, the system is configured. Good.

[Description of electronic device including semiconductor device]
Next, an electronic device including an inertial sensor, which is a specific example of a semiconductor device, will be described with a specific example.

FIG. 17 is an explanatory diagram showing a schematic configuration of a hard disk drive (hereinafter abbreviated as “HDD”), which is a specific example of an electronic device.
The HDD device 110 in the example includes a base member 111 and a cover 112 that covers the base member 111. On the base substrate 113 of the base member 111, a magnetic disk 114, its drive motor 115, an actuator arm 117 that rotates about a support shaft 116, and a magnetic head formed at the tip of the head via a head suspension 118. 119 etc. are provided. Furthermore, the inertial sensor 100 is installed on the base substrate 113. The inertial sensor 100 can be installed on the base member 111, the cover 112, and the like.

FIG. 18 is an explanatory diagram illustrating a schematic configuration of a notebook personal computer which is a specific example of the electronic apparatus.
In the illustrated example, an example of a notebook personal computer equipped with an HDD device is shown. (A) shows a state in which the display unit is opened, and (b) shows a state in which the display unit is closed.
A notebook personal computer 130 in the illustrated example includes a main body 131 including a keyboard 132 that is operated when characters and the like are input, a display unit 133 that displays an image, an HDD device 134, and the like. Among these, the HDD device 134 is manufactured by using a device on which the above-described inertial sensor 100 is mounted. In addition, the inertial sensor 100 may be attached to a board (not shown) of the notebook personal computer 130, a vacant area inside the casing constituting the main body 131 and the display unit 133.

FIG. 19 is an explanatory diagram showing a schematic configuration of a video camera device which is a specific example of the electronic apparatus.
The video camera device 170 shown in the figure has a main body 171 with a subject photographing lens 172 on the side facing forward, a start / stop switch 173 at the time of photographing, a display unit 174, a viewfinder 175, and an HDD device for recording the photographed image. 176 etc. are comprised. Among these, the HDD device 176 is manufactured by using a device on which the above-described inertial sensor 100 is mounted. Further, the inertial sensor 100 may be attached to a vacant area on the inner side of the casing constituting the substrate (not shown) of the video camera device 170 or the main body 171.

FIG. 20 is an explanatory diagram showing a schematic configuration of a game machine which is a specific example of the electronic device.
A game machine 150 shown in the figure includes a main body 151 including a first operation button group 152, a second operation button group 153 for operating a screen, a display unit 154 for displaying an image, an HDD device 155, and the like. . Among these, the HDD device 155 is manufactured by using a device on which the above-described inertial sensor 100 is mounted. Further, the inertial sensor 100 may be attached to a vacant region on the inner side of the casing (not shown) of the game machine 150 or the casing constituting the main body 151.

FIG. 21 is an explanatory diagram illustrating a schematic configuration of a mobile terminal device which is a specific example of the electronic apparatus.
In the illustrated example, a mobile phone is shown as an example of a mobile terminal device, (a) is a front view in an open state, (b) is a side view thereof, (c) is a front view in a closed state, ( d) is a left side view, (e) is a right side view, (f) is a top view, and (g) is a bottom view.
A cellular phone 190 shown in the figure includes an upper casing 191, a lower casing 192, a connecting portion (here, a hinge portion) 193, a display 194, a sub-display 195, a picture light 196, a camera 197, an acceleration sensor 198, and the like. It is configured. Among these, the acceleration sensor 198 is manufactured by using the inertial sensor 100 described above. Further, the acceleration sensor 198 may be attached to another position on the inner side of the upper casing 191 of the mobile phone 190, or to a vacant region on the inner side of the lower casing 192.

In the above-described first to fourth embodiments, preferred specific examples of the present invention have been described. However, the present invention is not limited to the contents, and may be appropriately changed without departing from the gist thereof. Is possible.
For example, in the above-described embodiment, the inertial sensor is given as a specific example of the semiconductor device, but the present invention is applied to other semiconductor devices as long as they are configured using a bonded substrate. Is possible.

It is explanatory drawing which shows typically the outline | summary of the manufacturing method of the semiconductor device which concerns on this invention. It is explanatory drawing which shows one specific example of the manufacturing method of the semiconductor device in the 1st Embodiment of this invention. It is explanatory drawing which shows a specific example of the scribe line in the 1st Embodiment of this invention. 1 is an external view showing a specific example of a semiconductor device according to a first embodiment of the present invention. It is explanatory drawing which shows one specific example of the manufacturing method of the semiconductor device in the 2nd Embodiment of this invention. It is explanatory drawing which shows a specific example of the scribe line in the 2nd Embodiment of this invention. It is an external view which shows one specific example of the semiconductor device in the 2nd Embodiment of this invention. It is explanatory drawing which shows one specific example of the manufacturing method of the semiconductor device in the 3rd Embodiment of this invention. It is explanatory drawing which shows a specific example of the scribe line in the 3rd Embodiment of this invention. It is an external view which shows one specific example of the semiconductor device in the 3rd Embodiment of this invention. It is explanatory drawing which shows one specific example of the manufacturing method of the semiconductor device in the 4th Embodiment of this invention. It is explanatory drawing which shows a specific example of the scribe line in the 4th Embodiment of this invention. It is an external view which shows one specific example of the semiconductor device in the 4th Embodiment of this invention. It is a signal block diagram which shows the operating principle of the inertial sensor which detects an inertial force. It is the flowchart which showed an example of the inertial force detection process. It is a schematic structure perspective view which shows one specific example of SIP containing an inertial sensor. It is explanatory drawing which shows schematic structure of HDD which is a specific example of an electronic device. It is explanatory drawing which shows schematic structure of the notebook type personal computer which is a specific example of an electronic device. It is explanatory drawing which shows schematic structure of the video camera apparatus which is a specific example of an electronic device. It is explanatory drawing which shows schematic structure of the game machine which is a specific example of an electronic device. It is explanatory drawing which shows schematic structure of the portable terminal device which is a specific example of an electronic device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Semiconductor substrate (bonded substrate), 11 ... First substrate, 12 ... Second substrate, 15, 21 ... Third substrate, 22 ... Wiring layer, 25 ... Fourth substrate, 100 ... Inertial sensor

Claims (7)

For the bonded substrate configured by bonding the first substrate and the second substrate, the first substrate is divided along the scribe line set for the first substrate from the first substrate side. A first dividing step to perform,
A second dividing step of dividing the second substrate along the scribe line set for the second substrate from the second substrate side with respect to the bonded substrate;
And an expanding step of expanding and separating the bonded substrate after the first dividing step and the second dividing step. For the bonded substrate configured by bonding the first substrate and the second substrate, the first substrate is divided along the scribe line set for the first substrate from the first substrate side. A first dividing step to perform,
A third substrate laminating step of laminating the surface of the bonded substrate after the first dividing step on the wiring forming surface of the third substrate;
A fourth substrate bonding step of bonding a fourth substrate to the surface of the bonded substrate after the first dividing step on the second substrate side;
For the laminate configured by bonding the third substrate and the fourth substrate to the bonded substrate, from the side of the fourth substrate, along the scribe line set for the second substrate, A second dividing step of dividing the second substrate and the fourth substrate;
And a expanding process for expanding and separating the laminate after the second dividing process. The method for manufacturing a semiconductor device according to claim 2, wherein in the first dividing step, the first substrate is divided by an etching process. The method of manufacturing a semiconductor device according to claim 2, wherein in the first dividing step, the first substrate is divided by performing modification by laser irradiation on the first substrate. 5. The method of manufacturing a semiconductor device according to claim 2, wherein in the second dividing step, the dividing of the second substrate is stopped halfway in the thickness direction of the second substrate. Provided with a bonded substrate configured by bonding a first substrate and a second substrate;
The bonded substrate is
From the first substrate side, along the scribe line set for the first substrate, a first cutting step for dividing the first substrate;
From the second substrate side, along a scribe line set for the second substrate, a second dividing step of dividing the second substrate;
A semiconductor device that is formed through an expanding process of expanding and separating after the first dividing process and the second dividing process. A semiconductor device having a bonded substrate configured by bonding a first substrate and a second substrate,
The bonded substrate in the semiconductor device is
From the first substrate side, along the scribe line set for the first substrate, a first cutting step for dividing the first substrate;
From the second substrate side, along a scribe line set for the second substrate, a second dividing step of dividing the second substrate;
An electronic device formed through an expanding step of expanding and separating after the first dividing step and the second dividing step.

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