JP2006086509A - Method for dividing semiconductor substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a method for dividing a semiconductor substrate wherein the dimension of a divided DAF and a metal thin film can be adapted to a semiconductor chip, thus allowing no packaging defect of a semiconductor chip to be generated. <P>SOLUTION: A notch 1a is formed in a DAF 2 and a semiconductor substrate 1 along an intended dividing line L1 by a diamond blade 3. Next, a part along the intended dividing line L1 is irradiated with a laser beam 4, so that a converging point P is formed in the semiconductor substrate 1, and a reformed area 1c by multiphoton absorption is formed in the converging point P. Next, by pulling a dicing film 5 in a direction shown by arrows F2 and F3, and the semiconductor substrate 1 is divided along the intended dividing line L1. Next, a pressing member 6 is moved in the direction shown by arrow F4 and a semiconductor chip 1e is picked up. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for dividing a semiconductor substrate, in which a mounting member for mounting the divided semiconductor substrate is divided in the thickness direction thereof.

Conventionally, as a method for dividing a semiconductor substrate of this type, a method of obtaining a semiconductor chip by cutting a semiconductor substrate such as a silicon wafer with a diamond blade rotating at high speed has been used. However, this method has a problem that the yield of the semiconductor chip is limited due to loss of silicon corresponding to the cutting width, and a problem that the yield is reduced due to chipping in which a part of the semiconductor chip is missing during cutting.
Therefore, a method has been proposed in which a condensing point is aligned inside the semiconductor substrate and laser light is irradiated, a modified region by multiphoton absorption is formed at the condensing point, and the modified region is divided from the starting point ( Patent Document 1). FIG. 4 is an explanatory view showing the method, and FIGS. 4A to 4C are explanatory views showing steps from formation of the modified region to division.
As shown to Fig.4 (a), it is the adhesive film (film adhesive) for mounting the semiconductor chip 1e produced | generated by the division | segmentation on the back surface (surface in which the element is not formed) of the semiconductor substrate 1. FIG. A die attach film (also referred to as a die bond film; hereinafter referred to as DAF) 2 is attached, and dicing is performed on the back surface (mounting side surface) of the DAF 2 so that the divided semiconductor chips are not dispersed. A film (also called a dicing sheet or dicing tape) 5 is attached. The DAF 2 and the dicing film 5 are formed, for example, by applying an adhesive on a synthetic resin film.
First, the laser beam 4 is irradiated from the surface of the semiconductor substrate 1 along the planned dividing line L1 under the laser irradiation conditions set so that the condensing point P is positioned below the inside of the semiconductor substrate 1. As a result, a phenomenon called optical damage occurs in the light condensing point P and its vicinity, thereby inducing thermal strain, cracks are generated in the portion, and the region where the cracks gather, that is, the modified region 1c is formed. It is formed. Subsequently, the condensing point P is moved to a position inside the semiconductor substrate above the modified region formed above, and a modified region 1c is formed along the planned dividing line L1, and the substrate below the planned dividing line L1. At least one continuous or intermittent layered modified region is formed in the thickness direction. The step of forming the reformed region 1c on the planned dividing line L1 is performed on each planned dividing line L1 (FIG. 4A). Subsequently, the dicing film 5 is pulled in both directions (directions indicated by arrows F2 and F3 in the figure) to generate a shear stress in the semiconductor substrate 1, thereby growing a crack that forms the modified region 1c and modifying the film. A crack 1b is formed on the line along the region 1c (FIG. 4B). Subsequently, the tip of the pressing member 6 is brought into contact with the back surface of the portion sandwiched between the cracks 1b and 1b, the pressing member 6 is moved upward (in the direction indicated by arrow F4 in the figure), and the semiconductor chip 1e is picked up. , DAF2 is torn off (FIG. 4C).

Japanese Patent No. 3408805 (paragraphs 77 to 81, FIGS. 28 to 32).

However, in the conventional method shown in FIG. 4, as shown in FIG. 4C, the DAF 2 is torn off when picking up the semiconductor chip 1 e, so that the DAF 2 is not divided along the scheduled division line L <b> 1. DAF 2b is generated, the sticking area at the time of mounting is reduced, and the strength of mounting is reduced. Further, when the DAF 2c that protrudes from the end portion of the semiconductor chip 1e occurs, there is a problem that the protruding portion hinders mounting. In addition, when the metal thin film for mounting the semiconductor chip 1e by soldering is used instead of the DAF, there is a problem similar to the case where the DAF is used.
In other words, the conventional method has a problem in that the size of the divided DAF and the metal thin film is not compatible with the semiconductor chip, which may cause a mounting failure of the semiconductor chip.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to realize a method for dividing a semiconductor substrate, in which the size of the divided DAF or metal thin film can be adapted to the semiconductor chip, and the mounting failure of the semiconductor chip does not occur.

In order to achieve the above object, according to the first aspect of the present invention, in the semiconductor device according to the first aspect, the semiconductor substrate in which the mounting member for mounting the divided semiconductor substrate is divided in the thickness direction is attached to the substrate surface. In the substrate dividing method, a mounting member dividing step for dividing at least the mounting member from a surface on the mounting member side along a planned dividing line for dividing the semiconductor substrate in the thickness direction, and the mounting member dividing step An attaching step of attaching a film-like member for preventing the discontinuity of the divided semiconductor substrate to the surface on the mounting member side where the mounting member is divided by the process, the surface on the mounting member side, and the surface thereof A laser beam is irradiated with a condensing point inside the semiconductor substrate along the planned dividing line from at least one of the substrate surfaces opposite to the substrate surface, and the condensing point is modified by multiphoton absorption. A modified region forming step of forming a semiconductor chip, and dividing the semiconductor substrate in the thickness direction along the planned dividing line after completion of the modified region forming step and the attaching step, thereby obtaining a semiconductor chip The technical means of providing a process is used.
In addition, the said condensing point is a location where the laser beam condensed.

  According to a second aspect of the present invention, in the method for dividing a semiconductor substrate according to the first aspect, the mounting member dividing step includes a surface on the mounting member side from the surface on the mounting member side along the planned cutting line. And a technical means for forming a cut reaching the inside of the semiconductor substrate.

  According to a third aspect of the present invention, a mounting member for mounting the divided semiconductor substrate is attached to the substrate surface, and further, the divided semiconductor substrate is prevented from being dispersed on the mounting surface of the mounting member. In a semiconductor substrate dividing method for dividing a semiconductor substrate having a film member attached thereto in the thickness direction, the first laser beam is irradiated from the surface on the mounting member side or the substrate surface opposite to the surface. And a mounting member dividing step of dividing the mounting member along a dividing line for dividing the semiconductor substrate in the thickness direction, and at least one of the surface on the mounting member side and the substrate surface on the opposite side Forming a modified region for forming a modified region by multiphoton absorption at the condensing point by irradiating a second laser beam with a converging point inside the semiconductor substrate along the planned dividing line from the surface Process and the actual Affixing a film-like member for preventing the separation of the divided semiconductor substrate on the surface on the mounting member side after the member dividing step and before or after the modified region forming step And a semiconductor substrate dividing step of dividing the semiconductor substrate in the thickness direction along the planned dividing line and obtaining a semiconductor chip after the modified region forming step and the attaching step are completed. Use appropriate means.

  According to a fourth aspect of the invention, in the method for dividing a semiconductor substrate according to the third aspect, the technical means of irradiating the first laser beam and the second laser beam from the same surface is used.

  According to a fifth aspect of the present invention, in the semiconductor substrate dividing method according to the third or fourth aspect, the first laser light and the second laser light are emitted from the same laser source. Use appropriate means.

  According to a sixth aspect of the present invention, in a method for dividing a semiconductor substrate in which the semiconductor substrate is divided in the thickness direction, the thickness of the semiconductor substrate is reduced from a mounting surface which is a surface on which the divided semiconductor substrate is mounted. A notch forming step of forming a notch of a predetermined depth reaching the inside of the semiconductor substrate along a dividing line for dividing in a direction, and the mounting surface on which the notch is formed by the notch forming step is divided A bonding step of bonding a film-like member for preventing dispersal of the formed semiconductor substrate, and at least one of the mounting surface and the substrate surface on the opposite side of the mounting surface, along the planned dividing line A modified region forming step of forming a modified region by multiphoton absorption at the focused point by irradiating a laser beam with a focused point inside the semiconductor substrate, the modified region forming step, and the Chakukotei use of technical means that is provided with a semiconductor substrate cutting step for obtaining a semiconductor chip by dividing the semiconductor substrate in the thickness direction along the cutting-scheduled line after completion.

  According to a seventh aspect of the present invention, in the method for dividing a semiconductor substrate according to any one of the first to sixth aspects, a surface on the mounting side of the semiconductor substrate is the same or different material as the semiconductor substrate material. And the mounting member is attached to the mounting side surface of the substrate. In the semiconductor substrate cutting step, the semiconductor substrate and the substrate are arranged in the thickness direction along the planned cutting line. The technical means of dividing and obtaining the semiconductor chip is used.

  According to an eighth aspect of the present invention, in the method for dividing a semiconductor substrate according to the sixth aspect, a substrate is formed of a material that is the same as or different from a semiconductor substrate material on the surface on the mounting side of the semiconductor substrate, In the semiconductor substrate dividing step, technical means is used in which the semiconductor chip is obtained by dividing the semiconductor substrate and the substrate in the thickness direction along the line to be divided.

  According to a ninth aspect of the present invention, in the method for dividing a semiconductor substrate according to the seventh aspect, the substrate has a coefficient of thermal expansion of the mounting member and a coefficient of thermal expansion of a mounting substrate on which the semiconductor chip is mounted. A technical means is used that is formed of a material that relieves stress generated between the mounting member and the mounting substrate due to the difference.

  According to a tenth aspect of the present invention, in the method for dividing a semiconductor substrate according to any one of the seventh to ninth aspects, a technical means that a material different from the semiconductor substrate is glass is used.

  According to an eleventh aspect of the invention, the semiconductor substrate according to any one of the first, second, third, fourth, fifth, seventh, ninth, and tenth aspects. The width between the divided sections of the semiconductor chip obtained by the dividing method, wherein the width between the divided sections of the mounting member formed by the dividing is the width between the divided sections of the surface of the semiconductor chip to which the mounting member is attached Use technical means that:

  According to a twelfth aspect of the present invention, in the semiconductor chip according to the eleventh aspect, the width between the divided sections of the mounting member formed by the division is a surface of the semiconductor chip on which the mounting member is attached. And the width between the divided surfaces of the surface on which the mounting member is mounted is equal to or smaller than the width between the divided surfaces of the surface on the opposite side to the surface on the mounting side. Use appropriate means.

  According to a thirteenth aspect of the present invention, there is provided a semiconductor chip obtained by the method for dividing a semiconductor substrate according to any one of the first to tenth aspects, wherein a surface of the mounting side of the semiconductor chip is mounted. A technical means is used in which the width between the divided surfaces is equal to or less than the width between the divided surfaces of the surface on the opposite side to the surface on the mounting side.

(Effect of the invention according to claim 1)
Before executing the semiconductor substrate cutting process, which divides the semiconductor substrate in the thickness direction along the planned cutting line, the mounting member cutting process is performed to cut at least the mounting member along the planned cutting line from the surface on the mounting member side. Therefore, unlike the conventional method of tearing the mounting member when the semiconductor substrate is divided, the divided mounting member is not short and does not protrude from the end of the semiconductor chip.
Therefore, the dimension of the divided mounting member can be adapted to the semiconductor chip, and a semiconductor substrate dividing method that does not cause mounting failure of the semiconductor chip can be realized.
In addition, the modified region is formed along the planned dividing line by laser light irradiation, and the semiconductor substrate is divided along the planned dividing line. There is no possibility that the yield of the semiconductor chip is limited due to the loss of the semiconductor substrate corresponding to the cutting width, and there is no possibility that the yield is lowered due to chipping in which a part of the semiconductor chip is missing at the time of cutting.

(Effect of the invention according to claim 2)
In addition to dividing the mounting member, a cut is formed in the semiconductor substrate in advance along the line to be divided, so that the substantial thickness of the semiconductor substrate to be divided is reduced, and the modification necessary for dividing the semiconductor substrate The number of layers in the region is small, and the laser irradiation time required for dividing the semiconductor substrate can be shortened. Moreover, the force required for dividing can be made smaller than when no cut is formed.
The same effect as that of the invention according to claim 1 can be obtained.

(Effect of the invention according to claim 3)
Before executing the semiconductor substrate cutting step of cutting the semiconductor substrate along the planned cutting line in the thickness direction, the first laser light is irradiated from the surface on the mounting member side or the substrate surface opposite to the surface to divide the semiconductor substrate. In order to execute a mounting member dividing process that divides the mounting member along the planned line, the divided mounting member becomes short in size as in the conventional method of tearing the mounting member when dividing the semiconductor substrate, or the semiconductor chip. It does not protrude from the end of the.
Therefore, the dimension of the divided mounting member can be adapted to the semiconductor chip, and a semiconductor substrate dividing method that does not cause mounting failure of the semiconductor chip can be realized.
Moreover, the conventional method of cutting the semiconductor substrate with a diamond blade in order to form the modified region along the planned dividing line by the irradiation of the second laser light and to cut the semiconductor substrate along the planned cutting line. As described above, there is no possibility that the yield of the semiconductor chip is limited due to the loss of the semiconductor substrate corresponding to the cutting width, and there is no possibility that the yield is lowered due to chipping in which a part of the semiconductor chip is missing during cutting.

(Effect of the invention according to claim 4)
Since the first laser beam and the second laser beam are irradiated from the same surface, the process of turning over the semiconductor substrate is eliminated depending on whether the first laser beam or the second laser beam is irradiated. Therefore, the time required for the entire process for dividing the semiconductor substrate can be shortened.
The same effect as that of the invention according to claim 3 can be obtained.

(Effect of the invention according to claim 5)
Since the first laser beam and the second laser beam are emitted from the same laser source, only one laser source needs to be provided, so that the laser irradiation apparatus for dividing the semiconductor substrate has a simple configuration. be able to.
Therefore, the failure rate and manufacturing cost of the apparatus can be reduced by the amount of laser sources compared to the case where a plurality of laser sources are provided. In addition, maintenance of the apparatus can be facilitated.
Further, if the first laser beam and the second laser beam emitted from the same laser source are irradiated from the same surface and the depth of the condensing point is changed, the mounting member is divided and modified. Since the formation of the regions can be performed continuously, the time required for dividing the semiconductor substrate can be shortened.
The same effects as those of the inventions according to claims 3 and 4 can be obtained.

(Effect of the invention according to claim 6)
A notch forming process for forming a notch to a predetermined depth along the planned cutting line from the mounting surface of the semiconductor substrate on which no mounting member is attached to the substrate surface, and a modified region along the planned cutting line by laser irradiation In combination with the modified region forming process to form the semiconductor substrate, the loss of the semiconductor substrate by the cutting width can be reduced and the yield of the semiconductor chip can be increased as compared with the conventional method of cutting the semiconductor substrate with only a diamond blade. can do. In addition, there is no possibility that the yield is lowered due to chipping in which a part of the semiconductor chip is cut during cutting. Furthermore, it is possible to reduce the time required for processing necessary for the division, compared to the case where only the modified layer is formed by laser irradiation and divided.

(Effect of the invention according to claim 7)
Even in the case where the substrate is formed of the same or different material as the semiconductor substrate material on the mounting side surface of the semiconductor substrate, and the mounting member is attached to the mounting side surface of the substrate, in the semiconductor substrate cutting process The semiconductor chip can be obtained by dividing the semiconductor substrate and the substrate in the thickness direction along the planned dividing line.

(Effect of the invention according to claim 8)
Even in the case where the substrate is formed of the same or different material as the semiconductor substrate material on the mounting side surface of the semiconductor substrate, in the semiconductor substrate cutting step, the semiconductor substrate and the substrate are arranged in the thickness direction along the planned cutting line. A semiconductor chip can be obtained by dividing.

(Effect of the invention according to claim 9)
The substrate is formed of a material that relieves stress generated between the mounting member and the mounting substrate due to a difference between the thermal expansion coefficient of the mounting member and the thermal expansion coefficient of the mounting substrate on which the semiconductor chip is mounted. Even in the case, in the semiconductor substrate cutting step, the semiconductor substrate and the substrate can be cut in the thickness direction along the line to be cut, thereby obtaining a semiconductor chip.

(Effect of the invention according to claim 10)
Even when the substrate is formed of glass which is a material different from that of the semiconductor substrate, in the semiconductor substrate cutting step, the semiconductor substrate and the substrate can be cut in the thickness direction along the planned cutting line to obtain a semiconductor chip. .

(Effect of the invention according to claim 11)
A semiconductor chip obtained by the semiconductor substrate cutting method according to any one of claims 1, 2, 3, 4, 5, 7, 9, and 10. The width between the divided sections of the mounting member formed by the division is equal to or smaller than the width between the divided sections of the surface of the semiconductor chip to which the mounting member is attached.
In other words, for example, when a mounting member is cut with a diamond blade and a semiconductor substrate is cut along a planned cutting line by irradiating a laser beam to form a modified region, the portion cut by the diamond blade is cut. Since the gap corresponding to the thickness of the blade of the diamond blade is formed, the width between the divided sections is reduced by that amount, but the semiconductor substrate is almost along the planned cutting line along the modified region. Since it is divided, the width between the divided sections of the mounting member is equal to or smaller than the width between the divided sections of the surface to which the mounting member is attached.
Therefore, a semiconductor chip in which the width between the divided sections of the mounting member formed by the division is equal to or smaller than the width between the divided sections of the surface to which the mounting member is attached is included in the semiconductor chip. It is assumed that the semiconductor substrate is obtained by the method for dividing a semiconductor substrate according to any one of claims 2, 3, 4, 5, 7, 8, and 9. Can do.

(Effect of the invention according to claim 12)
When mounting the mounting member on the board surface, when the mounting member is mounted on the board surface in a state where tension is applied to the mounting member in the surface direction, the mounting member is divided in the mounting member cutting step. May be shrunk in the direction between the divided sections from the divided part.
Therefore, the width between the divided sections of the divided mounting member is equal to or smaller than the width between the divided sections of the surface to which the mounting member is attached.
That is, the width between the divided sections of the mounting member formed by the division is equal to or less than the width between the divided sections of the surface of the semiconductor chip on which the mounting member is mounted, and the surface on which the mounting member is mounted The semiconductor chip in which the width between the divided sections is equal to or smaller than the width between the divided sections of the surface on the opposite side to the surface on the mounting side is also defined in claim 1, claim 2, claim 3, claim 4, claim 4, It can be estimated that the semiconductor substrate was obtained by the method for dividing a semiconductor substrate according to any one of claims 5, 7, 9, and 10.

(Effect of the invention according to claim 13)
A semiconductor chip obtained by the method for dividing a semiconductor substrate according to any one of claims 1 to 10, wherein the width between the divided sections of the surface on the mounting side of the semiconductor chip is the same as that on the surface on the mounting side. The width is less than or equal to the width between the split surfaces of the opposite surface.
That is, for example, when cutting from the mounting member to a predetermined depth of the semiconductor substrate with a diamond blade, and dividing the remaining semiconductor substrate in the thickness direction by irradiating a laser beam to form a modified region, Since a gap corresponding to the thickness of the blade of the diamond blade is formed in the portion cut by the diamond blade, the width between the divided sections is reduced accordingly, but the portion where the modified region is formed is approximately Since the cutting is performed according to the planned dividing line, the width between the divided surfaces on the mounting side is equal to or smaller than the width between the divided surfaces on the surface opposite to the surface on the mounting side.
Therefore, the semiconductor chip in which the width between the divided surfaces of the mounting side surface is equal to or smaller than the width between the divided surfaces of the surface opposite to the mounting side surface is described in any one of claims 1 to 10. It can be estimated that the semiconductor substrate was obtained by the method for dividing a semiconductor substrate.

<First Embodiment>
A first embodiment of the present invention will be described with reference to FIG. FIGS. 1A to 1D are explanatory views showing steps of a method for dividing a semiconductor substrate according to this embodiment.
(Step shown in FIG. 1 (a))
DAF 2 is attached to the back surface 1 g of the semiconductor substrate 1. First, the diamond blade 3 that rotates at high speed in the direction indicated by the arrow F1 in the figure cuts the DAF 2 along the planned dividing line L1, and further cuts the semiconductor substrate 1 until it reaches the inside (the mounting member of claim 1 of this application). Corresponding to the cutting process). This cutting is performed for each division planned line L1. As a result, the DAF 2 is divided along each division planned line L1, and a cut 1a is formed to the inside of the semiconductor substrate 1 along the planned division line L1. Note that DAF 2 corresponds to the mounting member described in the claims of the present application.

(Step shown in FIG. 1B)
Next, the dicing film 5 is stuck on the back surface (mounting side surface) of the DAF 2 (corresponding to the sticking step of claim 1 of the present application). Subsequently, the semiconductor substrate 1 is turned over, and the laser beam 4 is irradiated from the surface 1f so that the condensing point P is formed inside the semiconductor substrate 1 (on the extension of the cut 1a) along the line L1. Thus, a modified region 1c by multiphoton absorption is formed at the condensing point P of the laser beam 4 (corresponding to the modified region forming step of claim 1 of the present application). At this time, the depth of the condensing point P of the laser beam 4 is adjusted to any depth within the range of the thickness n of the portion where the notch 1a is not formed from the surface 1f of the semiconductor substrate 1. The modified layer 1c having the number of layers can be formed. For example, when the thickness n is relatively large, the condensing point P is moved in the thickness direction so that the modified region 1c is continuously formed in the thickness direction or formed at a plurality of locations, so that the division is easy. can do. Such a modified region 1c is formed for each of the planned dividing lines L1. The dicing film 5 corresponds to the film-like member described in the claims.

  Multiphoton absorption means that a substance absorbs a plurality of the same or different photons. Due to the multiphoton absorption, a phenomenon called optical damage occurs at the condensing point P of the semiconductor substrate 1 and the vicinity thereof, thereby inducing a thermal strain, a crack is generated in the portion, and a region where the crack is gathered. That is, the modified region 1c is formed. When the laser beam 4 is a pulse wave, the intensity of the laser beam is determined by the peak power density (W / cm 2) at the focal point. For example, the peak power density is 1 × 10 8 (W / cm 2) or more and the pulse width is 1 μs or less. Multiphoton absorption occurs under these conditions. As the laser light, for example, laser light from a YAG (Yttrium Aluminum Garnet) laser is used. The wavelength of the laser light is, for example, in the infrared light region of 1064 nm.

(Step shown in FIG. 1C)
Next, the dicing film 5 is pulled in both directions (directions indicated by arrows F2 and F3 in the figure) by a tape expanding device for pulling the dicing film, and the shearing stress is generated inside the semiconductor substrate 1, thereby modifying the film. A crack forming the region 1c is grown, and a crack 1b is formed on a line along the modified region 1c.

(Step shown in FIG. 1 (d))
Subsequently, the tip of the pressing member 6 is brought into contact with the back surface 1g of the portion sandwiched between the cracks 1b and 1b, the pressing member 6 is moved upward (in the direction indicated by arrow F4 in the figure), and the semiconductor chip 1e is picked up. (Corresponding to the semiconductor substrate cutting step of claim 1 of the present application).

(Semiconductor chip)
FIG. 5A is a longitudinal sectional view of the semiconductor chip obtained by the process shown in FIG. Of the semiconductor chip 1e, the width W2 between the divided surfaces of the surface on the mounting side (the surface containing the cut 1a) is between the divided surfaces of the surface opposite to the surface on the mounting side (the surface containing the crack 1b). Width W1 or less (W2 ≦ W1).
That is, as in this embodiment, the diamond blade 3 cuts from the DAF 2 to the predetermined depth of the semiconductor substrate 1, and the semiconductor substrate 1 in the remaining thickness direction is irradiated with the laser beam 4 to form the modified region 1c. When divided by forming, a gap corresponding to the thickness of the diamond blade 3 is formed in the cutting portion on the mounting side, and the width between the divided sections is reduced accordingly.
On the other hand, since the portion where the modified region 1c is formed is divided substantially according to the planned dividing line, the divided semiconductor chip 1e has a width W2 between the divided surfaces of the mounting side surface and the mounting side surface. The width is equal to or less than the width W1 between the sectional surfaces of the opposite surface.
Therefore, a semiconductor chip in which the width W2 between the divided surfaces of the mounting side surface is equal to or smaller than the width W1 between the divided surfaces of the surface opposite to the mounting side surface can be obtained by the semiconductor substrate dividing method of this embodiment. Can be estimated.

FIG. 7 shows another example of a longitudinal sectional view of the semiconductor chip obtained by the process shown in FIG.
The width W4 between the divided sections of the DAF 2 bonded to the back surface (mounting side surface) of the semiconductor chip 1e is formed to be equal to or less than the width W2 between the divided sections of the surface where the DAF 2 is bonded (W4 ≦ W2). ing.
That is, when the DAF 2 is melted by the laser beam 7 as in this embodiment, the DAF 2 disappears due to melting or a contracted portion is formed, so that the width between the cross sections of the DAF 2 decreases accordingly. ing. Further, when DAF2 is attached to the back surface 1g of the semiconductor substrate 1, when DAF2 is attached to the back surface 1g in a state where tension is applied to the DAF2 in the surface direction, the DAF2 is divided in the step of dividing the DAF2. If it is done, it may shrink in the direction between the divided sections (inner side) from the divided part. For this reason, the width between the divided sections of the divided DAF 2 may be reduced.
Accordingly, the width W4 between the divided sections of the DAF 2 formed by the division is equal to or smaller than the width W2 between the divided sections of the surface of the semiconductor chip 1e where the DAF 2 is attached, and the DAF 2 is attached. The semiconductor chip 1e in which the width W2 between the divided surfaces of the surface is equal to or smaller than the width W1 between the divided surfaces of the opposite surface is estimated to be obtained by the method for dividing the semiconductor substrate of the above embodiment. be able to.

[Effect of the first embodiment]
(1) As described above, if the method for dividing a semiconductor substrate according to the first embodiment is used, before performing the step of dividing the semiconductor substrate 1 in the thickness direction along the line L1 to be divided, In order to execute the process of dividing at least the DAF 2 from the back surface 1g along the planned division line L1, the divided DAF 2 becomes short as in the conventional method of tearing off the DAF 2 when dividing the semiconductor substrate 1, It does not protrude from the end of the semiconductor chip 1e.
Therefore, the size of the divided DAF 2 can be adapted to the semiconductor chip 1e, and a method for dividing the semiconductor substrate 1 that does not cause a mounting failure of the semiconductor chip 1e can be realized.
In addition, the modified region 1c is formed along the planned division line L1 by irradiation with the laser beam 4, and the semiconductor substrate 1 is cut along the planned division line L1, so that the semiconductor substrate 1 is cut with a diamond blade. As in the above method, there is no possibility that the yield of the semiconductor chip 1e is limited due to the loss of the semiconductor substrate 1 corresponding to the cutting width, and there is no possibility that the yield is reduced due to chipping in which a part of the semiconductor chip 1e is missing at the time of cutting.

(2) Further, not only the DAF 2 is divided, but the cut 1a is formed in the semiconductor substrate 1 in advance along the division line L1, so that the substantial thickness of the semiconductor substrate 1 to be divided is reduced. The number of modified layers 1c required for dividing the substrate 1 can be reduced, and the laser irradiation time required for dividing the semiconductor substrate 1 can be shortened. Moreover, the force required for dividing can be made smaller than when the cut 1a is not formed.
(3) Furthermore, since the laser beam 4 is hardly absorbed on the surface 1f of the semiconductor substrate 1, the surface 1f is not melted.

<Modified example of the first embodiment>
Next, a modified example of the first embodiment will be described with reference to FIG. FIGS. 8A to 8D are explanatory views showing the steps of the semiconductor substrate dividing method according to this modification. This modified example is characterized in that the glass substrate is formed on the mounting surface, and the semiconductor substrate 1 having the DAF 2 attached to the surface on the mounting side of the glass substrate is divided.

(Step shown in FIG. 8A)
A glass substrate 8 is formed on the back surface 1 g of the semiconductor substrate 1, and DAF 2 is attached to the mounting side surface of the glass substrate 8. The glass substrate 8 is a substrate for relaxing the stress generated between the DAF 2 and the circuit board due to the difference between the thermal expansion coefficient of the DAF 2 and the thermal expansion coefficient of the circuit board on which the semiconductor chip 1e is mounted. is there. In order to relieve the stress, a material having a thermal expansion coefficient intermediate between the thermal expansion coefficient of the semiconductor chip 1e and the thermal expansion coefficient of a mounting substrate such as a circuit board is selected, and the substrate has a certain thickness. If there exists, the said stress can be relieved. For example, instead of the glass substrate, a resin substrate, a substrate made of the same material as the semiconductor substrate (for example, a Si substrate) or the like can be used.
First, the diamond blade 3 that rotates at high speed in the direction indicated by the arrow F1 in the drawing cuts the DAF 2 and the glass substrate 8 along the planned dividing line L1, and further cuts the semiconductor substrate 1 until it reaches the inside. This cutting is performed for each division planned line L1. As a result, the DAF 2 is divided along each division planned line L1, and a cut 1a is formed to the inside of the semiconductor substrate 1 along the planned division line L1.
Note that only the DAF 2 and the glass substrate 8 can be cut along the planned dividing line L1 so as not to reach the inside of the semiconductor substrate 1. According to this cutting method, the cutting water sprayed to the diamond blade 3 during cutting enters the gap between the junctions of the semiconductor substrate 1 and the DAF 2, and the bonding force between the semiconductor substrate 1 and the DAF 2 decreases, or the semiconductor of the semiconductor chip 1e. There is no risk of deterioration of characteristics.

(Step shown in FIG. 8B)
Next, the dicing film 5 is attached to the back surface (mounting side surface) of the DAF 2. Subsequently, the semiconductor substrate 1 is turned over, and the laser beam 4 is irradiated from the surface 1f so that the condensing point P is formed inside the semiconductor substrate 1 (on the extension of the cut 1a) along the line L1. As a result, a modified region 1 c by multiphoton absorption is formed at the condensing point P of the laser beam 4. At this time, the depth of the condensing point P of the laser beam 4 is adjusted to any depth within the range of the thickness n of the portion where the notch 1a is not formed from the surface 1f of the semiconductor substrate 1. The modified layer 1c having the number of layers can be formed. For example, when the thickness n is relatively large, the condensing point P is moved in the thickness direction so that the modified region 1c is continuously formed in the thickness direction or formed at a plurality of locations, so that the division is easy. can do. Such a modified region 1c is formed for each of the planned dividing lines L1.

(Step shown in FIG. 8C)
Next, the dicing film 5 is pulled in both directions (directions indicated by arrows F2 and F3 in the figure) by a tape expanding device for pulling the dicing film, and the shearing stress is generated inside the semiconductor substrate 1, thereby modifying the film. A crack forming the region 1c is grown, and a crack 1b is formed on a line along the modified region 1c.

(Step shown in FIG. 1 (d))
Subsequently, the tip of the pressing member 6 is brought into contact with the back surface 1g of the portion sandwiched between the cracks 1b and 1b, the pressing member 6 is moved upward (in the direction indicated by arrow F4 in the figure), and the semiconductor chip 1e is picked up. To do.

(Semiconductor chip)
Assuming that the width between the divided sections of the divided glass substrate is W2, the same relationship as the relationship between the widths of the divided sections described with reference to FIGS. 5A and 7 in the first embodiment is established. Therefore, it can be estimated that the semiconductor chip satisfying the relationship is obtained by the method for dividing the semiconductor substrate according to the modified example of the first embodiment.
Even when the modification of the first embodiment is applied, the same effect as that of the first embodiment can be obtained.

Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIG. 2A to 2D are explanatory views showing the steps of the semiconductor substrate dividing method according to this embodiment. This embodiment is characterized in that only laser light is used and no cutting with a diamond blade is used. In addition, about the same structure and process as 1st Embodiment, description is simplified or abbreviate | omitted and the same code | symbol is used about the same structure.
(Step shown in FIG. 2A)
First, the laser beam 7 is irradiated from the front surface of the DAF 2 attached to the back surface 1g of the semiconductor substrate 1 along the planned dividing line L1 so that the focal point matches the DAF 2, and the DAF 2 is melted and divided. (Corresponding to the mounting member dividing step of claim 3 of the present application). The division of DAF2 is performed for each division planned line L1. The laser beam 7 has an intensity for melting and dividing the DAF 2.

(Step shown in FIG. 2B)
Next, the dicing film 5 is stuck on the back surface (the surface on the mounting side) of the DAF 2 (corresponding to the sticking step of claim 3 of the present application). Next, the semiconductor substrate 1 is turned over, and the surface of the semiconductor substrate 1 along the planned dividing line L1 under the laser irradiation conditions in which the laser beam 4 is set so that the condensing point P is located below the inside of the semiconductor substrate 1. The modified region 1c is formed at the condensing point P. Subsequently, the condensing point P is moved to a position inside the semiconductor substrate above the modified region formed above, and a modified region 1c is formed along the planned dividing line L1, and the substrate below the planned dividing line L1. At least one continuous or intermittent layer-like modified region is formed in the thickness direction. The step of forming the modified region 1c on the planned dividing line L1 is performed on each planned dividing line L1 (corresponding to the modified region forming step of claim 3 of the present application). 2a in the figure shows a mounting member dividing portion which is a portion where the DAF 2 is divided.

(Step shown in FIG. 2 (c))
Next, the dicing film 5 is pulled in both directions (directions indicated by arrows F2 and F3 in the figure) to generate a shear stress inside the semiconductor substrate 1, thereby growing a crack that forms the modified region 1c and modifying the film. A crack 1b is formed on a line along the region 1c.

(Step shown in FIG. 2 (d))
Subsequently, the tip of the pressing member 6 is brought into contact with the back surface 1g of the portion sandwiched between the cracks 1b and 1b, the pressing member 6 is moved upward (in the direction indicated by arrow F4 in the figure), and the semiconductor chip 1e is picked up. (Corresponding to the semiconductor substrate cutting step of claim 3).

(Semiconductor chip)
FIG. 5B is a longitudinal sectional view of the semiconductor chip obtained by the process shown in FIG. The width W2 between the sectional surfaces of the DAF 2 adhered to the back surface (mounting side surface) of the semiconductor chip 1e is formed to be equal to or less than the width W3 between the sectional surfaces of the surface to which the DAF 2 is adhered (W2 ≦ W3). ing.
That is, when the DAF 2 is melted by the laser beam 7 as in this embodiment, the DAF 2 disappears due to melting or a contracted portion is formed, so that the width between the cross sections of the DAF 2 decreases accordingly. ing.
On the other hand, since the semiconductor substrate 1 in which the modified region 1c is formed is divided according to a substantially divided line, the divided semiconductor chip 1e has a width W2 between the divided sections of the DAF 2 formed by the division. Of the chip 1e, the width is equal to or less than the width W3 between the sectional surfaces of the surface on which the DAF 2 is adhered.
Therefore, the semiconductor chip in which the width W2 between the divided sections of the DAF 2 formed by the division is equal to or smaller than the width W3 between the divided sections of the surface to which the DAF 2 is attached is the semiconductor chip 1e. It can be estimated that the semiconductor substrate was obtained by the method for dividing a semiconductor substrate.

[Effects of Second Embodiment]
As described above, if the semiconductor substrate dividing method according to the second embodiment is used, the laser beam is separated from the back surface 1g of the semiconductor substrate 1 before dividing the semiconductor substrate 1 along the planned dividing line L1 in the thickness direction. 7 to divide the DAF 2 along the division line L1, the divided DAF 2 may become short as in the conventional method of tearing off the DAF 2 when dividing the semiconductor substrate 1, or the semiconductor chip 1e. It does not protrude from the edge.
Therefore, the size of the divided DAF 2 can be adapted to the semiconductor chip 1e, and a method for dividing the semiconductor substrate 1 that does not cause a mounting failure of the semiconductor chip 1e can be realized.
In addition, the modified region 1c is formed along the planned division line L1 by irradiation with the laser beam 4, and the semiconductor substrate 1 is cut along the planned division line L1, so that the semiconductor substrate 1 is cut with a diamond blade. As in the above method, there is no possibility that the yield of the semiconductor chip 1e is limited due to the loss of the semiconductor substrate 1 corresponding to the cutting width, and there is no possibility that the yield is reduced due to chipping in which a part of the semiconductor chip 1e is missing at the time of cutting.

<Third Embodiment>
Next, a third embodiment of the present invention will be described with reference to FIG. 3A to 3D are explanatory views showing the steps of the method for dividing a semiconductor substrate according to this embodiment. This embodiment is characterized in that laser light is irradiated from the surface of a semiconductor substrate to divide the DAF and form a modified region. In addition, about the same structure and process as 2nd Embodiment, description is simplified or abbreviate | omitted and the same code | symbol is used about the same structure.
(Step shown in FIG. 3A)
First, the dicing film 5 is stuck on the DAF 2. Next, the laser beam 7 is irradiated from the surface 1f of the semiconductor substrate 1 along the planned dividing line L1 so that the focal point is aligned with the DAF 2, and the DAF 2 is melted and divided. Corresponds to the parting process). The division of DAF2 is performed for each division planned line L1.

(Steps shown in FIGS. 3B to 3D)
By performing the same steps as the steps shown in FIGS. 2B to 2D of the second embodiment, the semiconductor substrate 1 is divided along the respective division lines L1 and the semiconductor chip 1e is picked up.

(Semiconductor chip)
FIG. 5B is a longitudinal sectional view of the semiconductor chip obtained by the process shown in FIG. As in the second embodiment, the width W2 between the divided surfaces of the DAF 2 attached to the back surface (mounting side surface) of the semiconductor chip 1e is equal to the width W3 between the divided surfaces of the surface where the DAF 2 is attached. It is formed below (W2 ≦ W3).
Therefore, the semiconductor chip in which the width W2 between the divided sections of the DAF 2 formed by the division is equal to or smaller than the width W3 between the divided sections of the surface of the semiconductor chip 1e to which the DAF 2 is attached is described in this embodiment. It can be estimated that the semiconductor substrate was obtained by the method for dividing a semiconductor substrate.

[Effect of the third embodiment]
As described above, when the method for dividing a semiconductor substrate according to the third embodiment is used, the laser light 7 and the laser light 4 are emitted from the surface 1f of the semiconductor substrate 1. 4, the process of turning the semiconductor substrate 1 upside down can be eliminated, so that the time required for the entire process for dividing the semiconductor substrate 1 can be shortened.
In the third embodiment, the subsequent steps for forming the modified region 1c are the same as those in the second embodiment, and thus the same effects as those in the second embodiment can be obtained.

<Fourth embodiment>
Next, a fourth embodiment of the present invention will be described with reference to FIG. 6A to 6D are explanatory views showing the steps of the method for dividing a semiconductor substrate according to this embodiment. This embodiment is a method for dividing a semiconductor substrate for obtaining a semiconductor chip to be mounted without using a DAF, which is divided by using a combination of cutting with a diamond blade and formation of a modified region by laser light irradiation. It is characterized by that. In addition, about the same structure and process as 1st Embodiment, description is simplified or abbreviate | omitted and the same code | symbol is used about the same structure. A semiconductor chip obtained by this method for dividing a semiconductor substrate is connected to a circuit board by soldering, or is mounted by interposing an adhesive film or a liquid adhesive between the semiconductor chip and the circuit board. For example, in a flip chip, a solder bump is provided on a main surface of a semiconductor chip on which a semiconductor element is formed, and the main surface of the semiconductor chip and a wiring board on which the chip is mounted are connected to each other by the solder bump.

(Step shown in FIG. 6A)
DAF 2 is not attached to the back surface 1 g of the semiconductor substrate 1. First, the semiconductor substrate 1 is cut from the back surface 1g to a predetermined depth reaching the inside by the diamond blade 3 that rotates at high speed in the direction indicated by the arrow F1 in the drawing. This cutting is performed for each division planned line L1. Thereby, the cut 1a is formed as far as the inside of the semiconductor substrate 1 along the division line L1 (corresponding to the cut forming process of claim 6 of the present application).

(Step shown in FIG. 6B)
Next, the dicing film 5 is stuck to the back surface 1g of the semiconductor substrate 1 (corresponding to the sticking step of claim 6 of the present application). Subsequently, the laser beam 4 is irradiated from the surface 1f so that the condensing point P is formed inside the semiconductor substrate 1 (on the extension of the cut 1a) along the line to be cut L1. Thus, a modified region 1c by multiphoton absorption is formed at the condensing point P of the laser beam 4 (corresponding to the modified region forming step of claim 6 of the present application). At this time, the depth of the condensing point P of the laser beam 4 is adjusted to any depth within the range of the thickness n of the portion where the notch 1a is not formed from the surface 1f of the semiconductor substrate 1. The modified layer 1c having the number of layers can be formed. For example, when the thickness n is relatively large, the condensing point P is moved in the thickness direction so that the modified region 1c is continuously formed in the thickness direction or formed at a plurality of locations, so that the division is easy. can do. Such a modified region 1c is formed for each of the planned dividing lines L1.

(Step shown in FIG. 6C)
Next, the dicing film 5 is pulled in both directions (directions indicated by arrows F2 and F3 in the figure) by a tape expanding device for pulling the dicing film, and the shearing stress is generated inside the semiconductor substrate 1, thereby modifying the film. A crack forming the region 1c is grown, and a crack 1b is formed on a line along the modified region 1c.

(Step shown in FIG. 6D)
Subsequently, the tip of the pressing member 6 is brought into contact with the back surface 1g of the portion sandwiched between the cracks 1b and 1b, the pressing member 6 is moved upward (in the direction indicated by arrow F4 in the figure), and the semiconductor chip 1e is picked up. (Corresponding to the semiconductor substrate cutting step of claim 6).

(Semiconductor chip)
The semiconductor chip obtained by dividing according to this embodiment has the same shape as that obtained by removing DAF 2 from the semiconductor chip 1e shown in FIG. For this reason, as in the first embodiment, in the semiconductor chip 1e, the width W2 between the divided surfaces of the surface on the mounting side (the surface where the notch 1a is inserted) is the same as the surface on the opposite side to the surface on the mounting side. It is formed to have a width W1 or less (W2 ≦ W1) between the sectional surfaces (the surface containing the crack 1b).
That is, as in this embodiment, the diamond blade 3 cuts from the surface on the mounting side to a predetermined depth, and the remaining portion in the thickness direction is irradiated with the laser beam 4 to form the modified region 1c. When the cutting is performed, a gap corresponding to the thickness of the diamond blade 3 is formed in the cutting portion on the mounting side, and the width between the divided sections is reduced accordingly.
On the other hand, since there is no loss of the semiconductor substrate 1 due to the formation of the modified region 1c, the divided semiconductor chip 1e has a width W2 between the divided sections of the mounting side surface of the surface opposite to the mounting side surface. A width W1 or less between the cross sections.
Therefore, DAF2 is not adhered to the mounting side surface, and the width W2 between the divided surfaces of the mounting side surface is equal to or less than the width W1 between the divided surfaces of the surface opposite to the mounting side. Can be estimated to have been obtained by the semiconductor substrate cutting method of this embodiment.

[Effect of Fourth Embodiment]
(1) As described above, if the method for dividing a semiconductor substrate according to the fourth embodiment is used, the diamond blade extends from the mounting surface of the semiconductor substrate 1 on which the DAF 2 is not attached to the mounting surface along the planned cutting line L1. 3 is used in combination with the notch forming step for forming the notch to a predetermined depth by 3 and the modified region forming step for forming the modified region along the planned dividing line L1 by laser irradiation. The loss of the semiconductor substrate 1 corresponding to the cutting width can be reduced and the yield of the semiconductor chip 1e can be increased as compared with the conventional method of cutting only with a blade. Further, there is no possibility that the yield is lowered due to chipping in which a part of the semiconductor chip 1e is missing at the time of cutting. Furthermore, it is possible to reduce the time required for processing necessary for the division, compared to the case where only the modified layer is formed by laser irradiation and divided.

(2) Further, since the cut 1a is formed in the semiconductor substrate 1 along the division line L1 in advance, the substantial thickness of the semiconductor substrate 1 to be divided is reduced, and the modification necessary for dividing the semiconductor substrate 1 is performed. The number of layers of the quality layer 1c is small, and the laser irradiation time required for dividing the semiconductor substrate 1 can be shortened. Moreover, the force required for dividing can be made smaller than when the cut 1a is not formed.
(3) Furthermore, since the laser beam 4 is hardly absorbed on the surface 1f of the semiconductor substrate 1, the surface 1f is not melted.

<Other embodiments>
(1) In the second and third embodiments, different laser beams are used in the step of dividing the DAF 2 and the step of forming the modified region 1c. However, laser beams emitted from the same laser source are used. It can also be used to divide the DAF 2 and form the modified region 1c.
According to this method, since only one laser source needs to be provided, a laser irradiation apparatus for dividing the semiconductor substrate 1 can be simplified.
Therefore, the failure rate and manufacturing cost of the apparatus can be reduced by the amount of laser sources compared to the case where a plurality of laser sources are provided. In addition, maintenance of the apparatus can be facilitated.
In the third embodiment, if the laser beam 7 and the laser beam 4 emitted from the same laser source are irradiated from the surface 1f of the semiconductor substrate 1 and the depth of the condensing point P is changed, the DAF 2 Therefore, the time required for dividing the semiconductor substrate 1 can be shortened.

(2) In the first embodiment described above, the modified region 1c is formed after forming the cut 1a in the semiconductor substrate 1. However, it is also possible to form the cut 1a after forming the modified region 1c. . In this case, the same effect as that of the first embodiment can be obtained.
(3) In the fourth embodiment described above, the modified region 1c is formed after forming the cut 1a in the semiconductor substrate 1. However, it is also possible to form the cut 1a after forming the modified region 1c. . In this case, the same effect as that of the fourth embodiment can be obtained.
(4) In the second embodiment, the modified region 1c is formed after dividing the DAF 2, but the DAF 2 may be divided after forming the modified region 1c. In this case, the same effect as that of the second embodiment can be obtained.

(5) When the condensing point P of the laser beam is moved along the planned dividing line L1, the laser source may be moved, or the semiconductor substrate 1 may be moved in the vertical direction. Further, both the laser source and the semiconductor substrate 1 may be moved in directions opposite to each other. According to this method, the time for forming the modified region 1c can be shortened.
(6) When the modified region 1c is formed by irradiating the laser beam, the modified region 1c may be formed by irradiating the laser beam from both the front surface 1f and the back surface 1g of the semiconductor substrate 1. In this case, a modified region 1c may be formed by using a plurality of laser sources and irradiating laser light simultaneously or sequentially from both the front surface 1f and the back surface 1g.
(7) In the first to third embodiments described above, the case where the DAF is used as the mounting member for mounting the semiconductor chip 1e has been described. However, a metal thin film for mounting the semiconductor chip 1e by soldering is used. The present invention can also be applied when used as a mounting member. The present invention can also be applied when the mounting member is formed of resin or glass.

(8) The mounting member such as the DAF 2 and the metal thin film can be divided not only by a diamond blade but also by pressing an object having a sharp blade edge.
(9) A curved surface (swelled surface) of an object having a curvature (for example, a hemispherical object) is pressed against the semiconductor substrate 1 through the dicing film 5, thereby causing the arrows F2 and F3 on the semiconductor substrate 1. The semiconductor substrate 1 can also be divided by applying a corresponding force.

FIGS. 1A to 1D are explanatory views showing steps of a method for dividing a semiconductor substrate according to the first embodiment. 2A to 2D are explanatory views showing steps of a method for dividing a semiconductor substrate according to the second embodiment. FIGS. 3A to 3D are explanatory views showing steps of a method for dividing a semiconductor substrate according to the third embodiment. 4A to 4C are explanatory views showing a conventional method for dividing a semiconductor substrate. FIG. 5A is a vertical cross-sectional view of the semiconductor chip obtained by the process shown in FIG. 1D, and FIG. 5B is the semiconductor chip obtained by the process shown in FIG. It is a longitudinal cross-sectional view. 6A to 6D are explanatory views showing steps of a method for dividing a semiconductor substrate according to the fourth embodiment. FIG. 9 shows another example of a longitudinal sectional view of a semiconductor chip obtained by the process shown in FIG. FIGS. 8A to 8D are explanatory views showing the steps of the semiconductor substrate dividing method according to the modification of the first embodiment.

Explanation of symbols

  1 ... Semiconductor substrate, 1a ... Cut, 1b ... Crack, 1c ... Modified region, 1e ... Semiconductor chip, 1f ... Front, 1g ... Back, 2. DAF, 2a ... Mounting member division 3. Diamond blade 4. Laser beam 5 Dicing film 6 Pressing member 7 Laser beam 8 Glass substrate

Claims (13)

In a method for dividing a semiconductor substrate in which a mounting member for mounting the divided semiconductor substrate is divided in the thickness direction of the semiconductor substrate attached to the substrate surface,
A mounting member dividing step for dividing at least the mounting member along a dividing line for dividing the semiconductor substrate in the thickness direction from the surface on the mounting member side,
A sticking step of sticking a film-like member to prevent the divided semiconductor substrate from being separated on the surface of the mounting member where the mounting member is divided by the mounting member dividing step;
A laser beam is emitted from at least one of the surface on the mounting member side and the substrate surface on the opposite side of the surface to the inside of the semiconductor substrate along the planned dividing line to irradiate the laser beam. A modified region forming step of forming a modified region by multiphoton absorption at a point;
A semiconductor substrate cutting step for obtaining a semiconductor chip by dividing the semiconductor substrate in the thickness direction along the scheduled cutting line after the modified region forming step and the attaching step are completed,
A method for dividing a semiconductor substrate, comprising:   The said mounting member parting process forms the notch which reaches the inside of the said semiconductor substrate from the surface by the said mounting member along the said parting plan line from the said surface by the side of the said mounting member. Method for dividing a semiconductor substrate. A mounting member for mounting the divided semiconductor substrate is attached to the substrate surface, and a film-like member for preventing the separation of the divided semiconductor substrate is attached to the mounting surface of the mounting member. In the semiconductor substrate dividing method of dividing the semiconductor substrate in the thickness direction,
The first laser beam is irradiated from the surface on the mounting member side or the substrate surface opposite to the surface, and the mounting member is divided along a dividing line for dividing the semiconductor substrate in the thickness direction. Mounting member cutting step;
A second laser beam is irradiated from the at least one surface of the mounting member side surface and the opposite substrate surface to the inside of the semiconductor substrate along the planned dividing line with a second laser beam. A modified region forming step of forming a modified region by multiphoton absorption at the light spot;
A semiconductor substrate dividing step of obtaining a semiconductor chip by dividing the semiconductor substrate in the thickness direction along the planned dividing line after the modified region forming step is completed;
A method for dividing a semiconductor substrate, comprising:   4. The method for dividing a semiconductor substrate according to claim 3, wherein the first laser beam and the second laser beam are irradiated from the same surface.   5. The method for dividing a semiconductor substrate according to claim 3, wherein the first laser beam and the second laser beam are emitted from the same laser source. In a semiconductor substrate dividing method for dividing a semiconductor substrate in its thickness direction,
A notch having a predetermined depth reaching the inside of the semiconductor substrate from a mounting surface, which is a surface on which the divided semiconductor substrate is mounted, along a planned dividing line for dividing the semiconductor substrate in its thickness direction. A notch forming step to be formed;
A sticking step of sticking a film-like member for preventing the separation of the divided semiconductor substrate on the mounting surface on which the cut is formed by the cut forming step;
From at least one of the mounting surface and the substrate surface opposite to the mounting surface, a laser beam is irradiated to the inside of the semiconductor substrate along the line to be cut along the converging line to irradiate a laser beam. A modified region forming step for forming a modified region by photon absorption;
A semiconductor substrate cutting step for obtaining a semiconductor chip by dividing the semiconductor substrate in the thickness direction along the scheduled cutting line after the modified region forming step and the attaching step are completed,
A method for dividing a semiconductor substrate, comprising: On the mounting side surface of the semiconductor substrate, a substrate is formed of the same or different material as the semiconductor substrate material, and the mounting member is attached to the mounting side surface of the substrate,
7. The semiconductor chip is obtained by dividing the semiconductor substrate and the substrate in a thickness direction along the scheduled dividing line in the semiconductor substrate dividing step. 8. A method for dividing a semiconductor substrate according to 1. On the surface of the mounting side of the semiconductor substrate, a substrate is formed of the same or different material as the semiconductor substrate material,
The semiconductor substrate cutting method according to claim 6, wherein, in the semiconductor substrate cutting step, the semiconductor chip is obtained by cutting the semiconductor substrate and the substrate in a thickness direction along the line to be cut.   The substrate is made of a material that relieves stress generated between the mounting member and the mounting substrate due to a difference between the thermal expansion coefficient of the mounting member and the thermal expansion coefficient of the mounting substrate on which the semiconductor chip is mounted. The method for dividing a semiconductor substrate according to claim 7, wherein the semiconductor substrate is divided.   The method for dividing a semiconductor substrate according to claim 7, wherein the material different from that of the semiconductor substrate is glass.   A semiconductor chip obtained by the semiconductor substrate cutting method according to any one of claims 1, 2, 3, 4, 5, 7, 9, and 10. The width between the divided sections of the mounting member formed by the cutting is equal to or less than the width between the divided sections of the surface of the semiconductor chip to which the mounting member is attached. Chip.   The width between the divided sections of the mounting member formed by the division is equal to or less than the width between the divided sections of the surface of the semiconductor chip to which the mounting member is attached, and the mounting member is attached. 12. The semiconductor chip according to claim 11, wherein a width between the divided sections of the surface to be mounted is equal to or smaller than a width between the divided sections of the surface on the opposite side to the surface on the mounting side.   A semiconductor chip obtained by the method for dividing a semiconductor substrate according to claim 1, wherein a width between divided sections of a surface on a mounting side of the semiconductor chip is the mounting size. A semiconductor chip having a width equal to or smaller than a width between divided surfaces of a side surface and an opposite surface.

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