JP2023079907A - Method for cutting substrate and method for manufacturing small piece of substrate - Google Patents

Abstract

To cut a substrate having a first layer (cleavable layer) made of semiconductor single crystals and a second layer (non-cleavable layer) of glass formed on the surface of the first layer, using fewer processes and without requiring complex equipment adjustments.SOLUTION: A method for cutting a substrate S having a first layer LA1 consisting of a cleavable layer and a second layer LA2 consisting of a non-cleavable layer formed on the first layer LA1 includes the steps of forming a scribe line SL for the second layer LA2 only and cutting the substrate S along the scribe line SL.SELECTED DRAWING: Figure 6

Description

The present invention relates to a method for cutting a substrate having a first layer made of a semiconductor single crystal and a glass layer formed on the surface of the first layer, and a method for manufacturing substrate pieces from the substrate.

As a method for cutting a laminated substrate in which a glass layer is formed on the surface of a substrate made of a semiconductor single crystal such as Si, both the substrate made of a semiconductor single crystal and the glass layer thereon are irradiated with a laser beam to obtain a semiconductor. A modified layer is formed on both the single crystal substrate and the glass layer along the planned processing line, and the thermal stress generated by locally applying a temperature change to the laminated substrate cuts the laminated substrate from the modified portion as a starting point. is known to cut along a planned processing line (see Patent Document 1, for example).

Japanese Patent Application Laid-Open No. 2009-23215

In the conventional cutting method described above, in order to form the modified layer on both the substrate made of a semiconductor single crystal and the glass layer, the formation process of the modified layer is repeated multiple times along the same planned processing line (laser light irradiation) must be performed. Further, in order to irradiate a substrate made of a semiconductor single crystal with a laser beam, it is necessary to align the focal point of the laser beam with the surface of the substrate made of a semiconductor single crystal via a glass layer. It is difficult to adjust the focal position through the glass layer due to variations in the thickness of the glass layer, differences in the refractive index of the medium through which the laser beam passes, and the like. That is, conventional cutting methods require many processes and require complex equipment adjustments.

An object of the present invention is to produce a substrate having a first layer made of a semiconductor single crystal and a glass layer formed on the surface of the first layer with a smaller number of processes without requiring adjustment of complicated equipment. to be cut with

A plurality of aspects will be described below as means for solving the problem. These aspects can be arbitrarily combined as needed.
A method of cutting a substrate according to one aspect of the present invention is a method of cutting a substrate having a first layer made of a semiconductor single crystal and a second layer that is a glass layer formed on the first layer. The substrate cutting method includes the following steps.
A step of forming scribe lines only on the second layer.
A step of cutting the substrate along the scribe lines.

In the substrate cutting method described above, a process of forming scribe lines only on the second layer, which is a glass layer, is performed, and then the substrate is cut from the first layer side or the second layer side along the scribe lines. disconnecting. It is preferable to cut the substrate from the second layer side. When the substrate is cut along the scribe line by pressing the scribe line, the substrate can be cut from the second layer side by pressing the scribe line from the first layer side. In a substrate having a first layer made of a semiconductor single crystal and a second layer made of glass, if a scribe line is formed in the second layer, the first layer becomes the second layer when the substrate is cut. is cleaved according to the cleavage of As described above, since the above cutting method does not require formation of scribe lines on the first layer, it requires fewer processes than the conventional method, and requires complicated adjustment such as adjustment of the focal position through the glass layer. The substrate can be cut without cutting. That is, the present invention includes a cleavable layer and a cleavable layer formed on the cleavable layer. It can also be understood as a method of cutting a substrate with a non-lateral layer. The scribe line is formed with a predetermined thickness along a plane extending from the surface side to the back side of the layer on which the scribe line is formed (the plane perpendicular to the main surface of the layer on which the scribe line is formed). It can be a modified layer of thickness. In addition, scribe lines are accompanied by vertical cracks (cracks extending in the direction perpendicular to the main surface of the layer on which scribe lines are formed) from the surface side to the inside or back side of the layer on which the scribe lines are formed. can be.

The substrate may have a third layer which is a layer of glass formed on the side of the first layer opposite to the side on which the second layer is formed. In this case, scribe lines may be formed in the second and third layers. As a result, scribe lines are formed in both the second layer and the third layer, which are glass layers, so that the substrate can be easily cut at the time of breaking. The scribe lines on the third layer can be formed in the same manner as the scribe lines on the second layer.

A method of cutting a substrate according to another aspect of the present invention is a method of cutting a substrate having a cleavable first layer and a non-cleavable second layer formed on the first layer. The substrate cutting method includes the following steps.
A step of forming scribe lines only on the second layer.
A step of cutting the substrate along the scribe lines.

In the substrate cutting method described above, a process of forming scribe lines only on the second layer having no cleavability is performed, and then the substrate is cut from the first layer side or the second layer side along the scribe lines. disconnecting. In a substrate having a cleavable first layer and a non-cleavable second layer, if a scribe line is formed in the non-cleavable second layer, the first layer is cut when the substrate is cut. is cleaved according to the cutting of the second layer. As described above, the above cutting method does not require formation of scribe lines on the first layer, and therefore requires fewer processes than the conventional method, and requires complicated adjustment such as adjustment of the focal position via the second layer. The substrate can be cut without cutting.

The substrate may have a non-cleavable third layer formed on the side of the first layer opposite to the side on which the second layer is formed. In this case, scribe lines may be formed in the second and third layers. As a result, scribe lines are formed in both the second layer and the third layer, which do not have cleavability, making it easier to cut the substrate at the time of breaking. Further, after forming scribe lines on the second layer and the third layer, the substrate can be cut by pressing the scribe lines from the second layer side or the third layer side.

In the cutting step, the substrate may be cut along the scribe lines by pushing the scribe lines. As a result, the substrate can be cut by a simple method of pressing the scribe line.

In a substrate having a second layer and a third layer, the thickness of the second layer may be smaller than the thickness of the third layer. In this case, cutting of the substrate may be performed by pushing the substrate from the second layer side. This makes it easier to cut the substrate along the scribe lines.

In the step of forming the scribe lines, the scribe lines are formed by first applying a laser beam having a pulse width of picosecond order (for example, 0.1 picosecond or more and 100 picosecond or less, particularly 1 picosecond or more and 50 picosecond or less). It may be formed by irradiating two layers. Thereby, a scribe line (for example, a scribe line made of a modified layer) can be selectively formed in the second layer, which is a glass layer.

The above laser light may have a wavelength in the infrared region (for example, 750 nm or more and 4000 nm or less, particularly 750 nm or more and 2500 nm or less, specifically the fundamental wave of a YAG laser). Thereby, a scribe line (for example, a scribe line made of a modified layer) can be properly formed in the second layer, which is a glass layer.

The first layer may be a silicon substrate. As a result, the first layer can be cut using the cleaving property of the silicon substrate, so that the substrate can be properly cut.

A manufacturing method according to still another aspect of the present invention manufactures a substrate piece from a substrate having a first layer made of a semiconductor single crystal and a second layer that is a glass layer formed on the first layer. The method. A method for manufacturing a substrate piece includes the following steps.
A step of forming scribe lines only on the second layer.
A step of cutting the substrate along the scribe lines.

In the above method for manufacturing a small substrate piece, the process of forming scribe lines on a substrate having a first layer made of a semiconductor single crystal and a second layer made of glass is performed on the second layer made of glass. is running only for After that, the substrate is cut by pressing the scribe line from the first layer side or the second layer side along the scribe line, thereby cutting out the substrate pieces from the substrate. In a substrate having a first layer made of a semiconductor single crystal and a second layer made of glass, if a scribe line is formed in the second layer, the first layer becomes the second layer when the substrate is cut. is cleaved according to the cleavage of In this way, the above-described method for manufacturing substrate pieces does not require formation of scribe lines on the first layer. Substrate strips can be manufactured without the need for

The substrate may have a third layer which is a layer of glass formed on the side of the first layer opposite to the side on which the second layer is formed. In this case, scribe lines may be formed in the second and third layers. As a result, scribe lines are formed in both the second layer and the third layer, which are glass layers, so that the substrate can be easily cut at the time of breaking.

A substrate strip method according to yet another aspect of the present invention has a first layer comprising a layer having cleavability and a second layer comprising a layer having no cleavability formed on the first layer. A method of manufacturing a substrate piece from a substrate. A method for manufacturing a substrate piece includes the following steps.
A step of forming scribe lines only on the second layer.
A step of cutting the substrate along the scribe lines.

In the above-described method for manufacturing a small substrate piece, the process of forming scribe lines on a substrate having a first layer made of a layer having cleavability and a second layer being a layer not having cleavability is performed by We are only doing it for the second layer, which we don't have. After that, the substrate is cut by pressing the scribe line from the first layer side or the second layer side along the scribe line, thereby cutting out the substrate pieces from the substrate. In a substrate having a cleavable first layer and a non-cleavable second layer, if a scribe line is formed in the second layer, the first layer is separated from the second layer when the substrate is cut. It is cleaved according to the cleavage. In this way, the above-described method for manufacturing substrate pieces does not require formation of scribe lines on the first layer, so that fewer processes than in the prior art can be used to perform complex adjustments such as focal point adjustment via the second layer. Substrate strips can be manufactured without the need for

The substrate may have a non-cleavable third layer formed on the side of the first layer opposite to the side on which the second layer is formed. In this case, scribe lines may be formed in the second and third layers. As a result, scribe lines are formed in both the second layer and the third layer, which do not have cleavability, making it easier to cut the substrate at the time of breaking.

A substrate having a first layer made of a semiconductor single crystal and a second layer made of glass formed on the surface of the first layer, or a first layer having a cleavage property and cleavage formed on the surface of the first layer A substrate having a second layer having no properties can be cut in fewer processes and without the need for complex equipment adjustments.

The figure which shows the cross-section of a board|substrate. Schematic diagram of a scribe line forming apparatus. FIG. 2 is a diagram showing the configuration of a transmission optical system; Schematic which shows the structure of a breaking apparatus. 4 is a flow chart showing a method for cutting a substrate; The figure which shows typically the cutting method of a board|substrate. A microscope image of a cut surface of a substrate piece.

1. First Embodiment (1) Substrate Hereinafter, a method for cutting and manufacturing a substrate piece SS from a substrate S according to the present disclosure will be described. The substrate S from which the substrate pieces SS are cut has a plurality of structures (for example, MEMS devices) arranged vertically and horizontally in a plan view. The substrate piece SS has a quadrangle containing a predetermined number of these structures.

On the other hand, the cross section of the substrate S has a structure as shown in FIG. A small substrate piece SS cut out from the substrate S also has the same cross-sectional structure. FIG. 1 is a diagram showing a cross-sectional structure of a substrate. The substrate S is a laminated substrate having a first layer LA1, a second layer LA2, and a third layer LA3.

The first layer LA1 is a cleavable substrate. Specifically, the first layer LA1 is a plate-like substrate made of a semiconductor single crystal. The first layer LA1 is, for example, a silicon (Si) substrate. The crystal orientation of the first layer LA1, which is a silicon substrate, is (111) and has the property (cleavage) that it is easily cracked in a specific direction. The second layer LA2 is a non-cleavable layer laminated by being fixed on the first surface SU1 of the first layer LA1. The second layer LA2 is, for example, a plate-like substrate made of glass. Glass substrates generally do not have cleavage.

The third layer LA3 is a non-cleavable layer laminated by being fixed on the second surface SU2 of the first layer LA1 opposite to the first surface SU1. The third layer LA3 is, for example, a plate-like substrate made of glass. The thickness of the second layer LA2 is smaller than the thickness of the third layer LA3.

As described above, the substrate S to be processed in the present disclosure includes the plate-like first layer LA1 having cleavability, the plate-like second layer LA2 and third layer LA3 (glass layers) having no cleavability. ). When cutting out the substrate pieces SS from the substrate S, a process of forming scribe lines SL only on the second layer LA2 and the third layer LA3, which are glass layers, along the boundary lines of the substrate pieces SS is executed. do. That is, the process of forming the scribe line SL is not performed on the first layer LA1. Thereafter, by breaking the substrate S along the formed scribe lines SL, the substrate pieces SS can be cut out from the substrate S.

Note that the scribe lines SL are formed on a plane extending from the surface side to the back side of the layers (the second layer LA2 and the third layer LA3) on which the scribe lines SL are formed (the principal surfaces of the layers on which the scribe lines SL are formed). It is a modified layer of a predetermined thickness formed along a plane perpendicular to the surface of the substrate. In addition, the scribe line SL is a vertical crack extending from the surface side of the layer on which the scribe line SL is formed to the inside or the back side (that is, a crack extending in the direction perpendicular to the main surface of the layer on which the scribe line SL is formed). ).

(2) Scribe Line Forming Apparatus A scribe line forming apparatus 100 for forming scribe lines SL on the second layer LA2 and the third layer LA3 of the substrate S will be described below with reference to FIG. FIG. 2 is a schematic diagram of a scribe line forming apparatus. The scribe line forming apparatus 100 is an apparatus that forms scribe lines SL in the second layer LA2 and the third layer LA3 by irradiating the second layer LA2 and the third layer LA3, which are glass layers, with laser light. A scribe line forming apparatus 100 includes a laser system 1 , a processing table 3 , a table driving section 5 and a control section 7 .

The laser system 1 outputs laser light for forming a scribe line SL on the substrate S (referred to as processing laser light L1). Specifically, the laser system 1 has a laser device 11 , a transmission optical system 13 and a drive mechanism 15 . The laser device 11 outputs laser light L2 to be incident on the transmission optical system 13 . The laser device 11 has a laser oscillator 11a and a laser controller 11b. The laser oscillator 11a outputs pulsed laser light L2 having a wavelength in the infrared region at a predetermined irradiation cycle. The laser oscillator 11a is, for example, a YAG laser oscillator. This laser oscillator 11a outputs the fundamental wave of the YAG laser as laser light L2. The wavelength output from this laser oscillator 11a is, for example, 750 nm or more and 4000 nm or less. More preferably, it is 750 nm or more and 2500 nm or less.

Note that the irradiation period mentioned above refers to the time from when one laser light pulse is output until when the next laser light pulse is output.

The pulse width of the laser light L2 from the laser oscillator 11a is set to the order of picoseconds. Specifically, the pulse width of the laser beam L2 (processing laser beam L1) is set to 100 femtoseconds or more and 100 picoseconds or less. More preferably, it is set to 1 picosecond or more and 50 picosecond or less. The processing laser beam L1 having such a pulse width on the order of picoseconds has a wavelength range that passes through the glass and has a high peak energy, so that the processing laser beam L1 is a modified layer over the entire thickness direction of the glass layer. It is possible to form marks (that is, scribe lines SL). On the other hand, since silicon absorbs the processing laser beam L1 having a pulse width on the order of picoseconds at the incident surface, no processing marks are formed inside the silicon. Therefore, by using the processing laser beam L1 having a pulse width on the order of picoseconds in the process of forming the scribe lines SL, processing marks that become the scribe lines SL are likely to be formed in the glass layer, while the first Processing marks (scribe lines SL) are less likely to be formed in the layer LA1. That is, the scribe line SL can be formed only on the glass layer by using the processing laser beam L1 having a pulse width on the order of picoseconds.

The laser control unit 11b controls the laser oscillator 11a according to the generation conditions of the laser light L2 (irradiation cycle, intensity of the laser light L2, etc.).

The transmission optical system 13 receives the laser beam L2 output from the laser device 11, and outputs the laser beam L2 whose beam diameter on the substrate S is adjusted. Specifically, the transmission optical system 13 has an axicon lens 131 and a reduction optical system 133, as shown in FIG. FIG. 3 is a diagram showing the configuration of a transmission optical system.

The axicon lens 131 receives the laser beam L2 and converts the incident laser beam L2 into a ring beam L3 having a constant ring width w in the propagation direction of the laser beam. The reducing optical system 133 receives the ring beam L3, reduces the incident ring beam L3, and forms the processing laser beam L1 on the substrate S whose beam diameter is adjusted. The reduction optical system 133 is composed of, for example, a plurality of lenses.

Since the transmission optical system 13 has the above configuration, the laser beam L2 output from the laser device 11 can be converted into the processing laser beam L1 that is optimal for forming the scribe line SL.

In addition to the axicon lens 131 and reduction optical system 133, the transmission optical system 13 may include other optical members such as a λ/4 wavelength plate, a beam expander, and a prism.

The driving mechanism 15 adjusts the beam diameter of the processing laser beam L1 on the substrate S in the optical axis direction (propagation direction).

The processing table 3 is a table on which the substrate S is placed. A table drive unit 5 (an example of a drive unit) moves the processing table 3 with respect to the laser system 1 (transmission optical system 13). The table drive unit 5 is a known mechanism having, for example, guide rails, a motor, and the like.

The control unit 7 has a processor (eg, CPU), a storage device (eg, ROM, RAM, HDD, SSD, etc.), and various interfaces (eg, A/D converter, D/A converter, communication interface, etc.). computer system. The control unit 7 performs various control operations in the scribe line forming apparatus 100 by executing programs stored in a storage unit (corresponding to part or all of the storage area of the storage device). The control unit 7 may be composed of a single processor, or may be composed of a plurality of independent processors for each control.

The controller 7 outputs, for example, the set value of the output condition of the laser beam L2 to the laser controller 11b. The control unit 7 also controls the drive mechanism 15 to adjust the beam diameter of the processing laser beam L1 on the substrate S. As shown in FIG.

Furthermore, the control unit 7 moves the processing table 3 in the horizontal direction by controlling the table driving unit 5, thereby moving the substrate S with respect to the processing laser beam L1. That is, the control unit 7 moves the substrate S with respect to the processing laser beam L1 to scan the substrate S with the processing laser beam L1. Further, the control unit 7 controls the scanning speed of the processing laser beam L1 on the substrate S by adjusting the moving speed of the processing table 3 in the horizontal direction.

Although not shown, the controller 7 is connected with sensors for detecting the size, shape and position of the substrate S, sensors and switches for detecting the state of each part of the scribe line forming apparatus 100, and an information input device. there is

(3) Breaking Device Next, a breaking device 200 for breaking the substrate S along the scribe line SL will be described with reference to FIG. FIG. 4 is a schematic diagram showing the configuration of the breaking device. The breaking device 200 is a device that cuts the substrate S by three-point bending breaking. That is, the breaking device 200 is a device for cutting the substrate S along the scribe lines SL by pressing the substrate S at the scribe line SL formation locations. It has a break plate 21 and a pair of receiving blades 23 .

The break plate 21 is a member for pushing the scribe line SL formed portion of the substrate S toward the pair of receiving blades 23 to cut the substrate S along the scribe line SL. The break plate 21 is, for example, a member made of zirconia. The pair of receiving blades 23 is a member for holding the substrate S arranged at a predetermined interval (for example, about several mm). In the breaking device 200 , the substrate S is aligned so that the scribe line SL is arranged in the space between the pair of receiving blades 23 .

When breaking the substrate S using the breaking device 200, the surface of the substrate S facing the break plate 21 is protected by the wafer tape WT. On the other hand, the surface of the substrate S facing the pair of receiving blades 23 is protected by a protective film F disposed between the wafer ring WR and the pair of receiving blades 23 .

(4) Substrate Cutting Method A method of cutting the substrate S along the planned processing lines to cut out the substrate pieces SS will be described with reference to FIGS. FIG. 5 is a flow chart showing a method for cutting a substrate. FIG. 6 is a diagram schematically showing a method of cutting a substrate. First, the substrate S to be processed is placed on the processing table 3 so that the side of the second layer LA2, which is a glass layer having no cleavability, becomes the irradiation surface of the processing laser beam L1.

Thereafter, in step S1, the laser device 11 generates a laser beam L2 at a predetermined irradiation cycle, and the processing laser beam L1 having a predetermined beam diameter is directed from the transmission optical system 13 toward the surface of the second layer LA2 of the substrate S. to emit light. While emitting the processing laser beam L1, the table driving unit 5 is driven to move the processing table 3 in the horizontal direction. Scan. Specifically, the processing laser beam L1 is scanned in two directions, ie, the vertical and horizontal sides of the substrate piece SS.

As described above, the processing laser beam L1 is an infrared region laser beam having a pulse width on the order of picoseconds. Therefore, as shown in (1) of FIG. 6, the processing laser beam L1 can form a scribe line SL in the second layer LA2 which is a glass layer having no cleavability, but the scribe line SL can be formed in the silicon substrate having the cleavability. The scribe line SL is scarcely formed in the first layer LA1.

After forming the scribe line SL on the second layer LA2, as shown in FIG. A processing laser beam L1 is applied. As a result, scribe lines SL are formed in the third layer LA3, which is a glass layer having no cleavability.

The order of forming the scribe lines SL is not limited to the above. The scribe lines SL are formed by first irradiating the third layer LA3 with the processing laser beam L1, and then the second layer LA2 is irradiated with the processing laser beam L1. scribe lines SL may be formed.

After forming the scribe lines SL on the second layer LA2 and the third layer LA3, in step S2, the substrate S is cut along the scribe lines SL using the breaking device 200, thereby cutting out the substrate pieces SS from the substrate S. . Specifically, the substrate S is cut along the scribe lines SL by pushing the scribe lines SL of the substrate S toward the pair of receiving blades 23 with the break plate 21 .

When breaking the substrate S by the breaking device 200, it is preferable to press the substrate S from the side of the second layer LA2, which is a thin glass layer, as shown in (3) and (4) of FIG. . Although it is possible to press the substrate S from the side of the third layer LA3, which is a thick glass layer, to break the substrate S, the present inventors generally It was found that the substrate S tends to be cut by breaking the substrate S from the second layer LA2 side having a smaller thickness than breaking the substrate S from the LA3 side.

(5) Examples Hereinafter, examples of cutting out the substrate pieces SS from the substrate S by the method for cutting the substrate S described above will be described. In this example, as the substrate S to be processed, a laminated substrate was used in which a glass layer (second layer LA2), a silicon substrate (first layer LA1), and a glass layer (third layer LA3) were sequentially laminated. The thicknesses of the glass layer (second layer LA2), the silicon substrate (first layer LA1), and the glass layer (third layer LA3) are 300 μm, 150 μm, and 500 μm, respectively.

Infrared light having a pulse width of 15 picoseconds or less and a wavelength of 1060 nm was used as the processing laser light L1. The energy per pulse of the processing laser beam L1 is 340 μJ. This processing laser beam L1 was output along the scribe line SL at a scanning speed of 100 mm per second while outputting 22500 times per second. In addition, the processing laser beam L1 was scanned only once along the scribe line SL.

In order to cut out a square substrate piece SS from the substrate S, the second layer LA2 and the third layer LA3 were irradiated with the processing laser beam L1 along the vertical and horizontal sides of the substrate piece SS. After that, the substrate S was cut along the vertical and horizontal scribe lines SL using the breaking device 200 to cut out the substrate pieces SS. The breaking of the substrate S was performed from the side of the second layer LA2 having a smaller thickness.

In addition, for example, due to the thickness of the second layer LA2 and/or the third layer LA3, which are glass layers having no cleavability, the scribe formed by scanning the processing laser beam L1 only once In the line SL, when it is difficult to cut the substrate S by the breaking device 200, the processing laser beam L1 may be scanned a plurality of times to form the scribe line SL. As a result, the scribe line SL extending further in the thickness direction of the second layer LA2 and/or the third layer LA3 can be formed, so that the substrate S can be easily cut by the breaking device 200 .

FIG. 7 shows a microscope image of a cut surface of the substrate piece SS after being cut out from the substrate S. As shown in FIG. (1) in FIG. 7 is a cut surface along one of the vertical or horizontal sides of the small substrate piece SS, and (2) in FIG. 7 is a cut of the small substrate piece SS along the other side of the small substrate piece SS. It is the surface. FIG. 7 is a microscope image of a cut surface of the substrate piece.

As shown in FIG. 7, the substrate S can be cut in both the vertical and horizontal directions of the substrate piece SS. However, the state of the cut surface of the first layer LA1 was different between the vertical side and the horizontal side. Specifically, while no uncut portion was found on one cut surface, some uncut portion was found on the other cut surface. This is because of the cleavability of the first layer LA1 made of a semiconductor single crystal, and the relationship between the susceptibility to cracking of the first layer LA1 in the direction along the vertical side and the direction along the horizontal side and the position at which the crack is likely to occur and the scribe line SL. This is probably due to the difference in position.

As described above, in the method for cutting the substrate S of the present disclosure, only the second layer LA2 and the third layer LA3, which are glass layers, are irradiated with the processing laser beam L1, and the substrate along the scribe line SL formed thereby. The substrate S can be cut only by breaking the S. That is, in the method for cutting the substrate S of the present disclosure, the substrate S can be cut with fewer processes and without requiring complicated device adjustments.

2. Other Embodiments Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the invention. In particular, multiple embodiments and modifications described herein can be arbitrarily combined as required.
(A) The first layer LA1 may be a substrate made of a semiconductor single crystal other than a silicon substrate, or may be a substrate having a cleavage property other than a silicon substrate.

(B) The substrate S may have only the second layer LA2 as a glass layer or a non-cleavable layer. That is, a glass layer or a non-cleavable layer may be formed only on one side of the first layer LA1. In this case, the scribe line SL may be formed (irradiated with the processing laser beam L1) only on the second layer LA2. In this case, the cutting of the substrate S by breaking is preferably performed from the side of the first layer LA1 that does not have cleavability. When the substrate S is cut along the scribe line SL by pressing the scribe line SL, the substrate S can be cut from the second layer LA2 side by pressing the scribe line SL from the first layer LA1 side.

(C) The formation of the scribe line SL in the second layer LA2 and/or the third layer LA3, which is a glass layer or a layer having no cleavability, is a method other than irradiation with a laser beam having a pulse width on the order of picoseconds. can be done by For example, the scribe line SL may be formed by a method using a scribe wheel.

(D) The break of the substrate S is not limited to the three-point bending break. For example, other breaking methods such as table breaking (a breaking method in which the scribe line SL formed on the substrate S placed on the table is cut by pressing with a break plate) can be used.

INDUSTRIAL APPLICABILITY The present invention can be widely applied to cutting a substrate having a first layer made of a semiconductor single crystal and a glass layer formed on the surface of the first layer. Further, the present invention can be widely applied to cutting a substrate having a cleavable first layer and a non-cleavable layer formed on the surface of the first layer.

100 scribe line forming device 1 laser system 11 laser device 11a laser oscillator 11b laser control unit 13 transmission optical system 131 axicon lens 133 reduction optical system 15 drive mechanism L1 processing laser beam L2 laser beam L3 ring beam 3 processing table 5 table driving unit 7 control unit 200 breaking device 21 breaking plate 23 receiving blade F protective film WR wafer ring WT wafer tape S substrate SS substrate piece SU1 first surface SU2 second surface LA1 first layer LA2 second layer LA3 third layer SL scribe line

Claims (13)

A method for cutting a substrate having a first layer made of a semiconductor single crystal and a second layer that is a glass layer formed on the first layer, comprising:
forming a scribe line only on the second layer;
cutting the substrate along the scribe lines;
A cutting method comprising: The substrate has a third layer, which is a layer of glass, formed on the side of the first layer opposite to the side on which the second layer is formed,
2. The cutting method according to claim 1, wherein said scribe lines are formed in said second layer and said third layer. A method for cutting a substrate having a cleavable first layer and a non-cleavable second layer formed on the first layer, comprising:
forming a scribe line only on the second layer;
cutting the substrate along the scribe lines;
A cutting method comprising: the substrate has a non-cleavable third layer formed on the side of the first layer opposite to the side on which the second layer is formed;
4. The cutting method according to claim 3, wherein said scribe line is formed in said second layer and said third layer. 5. The cutting method according to claim 1, wherein in said cutting step, said substrate is cut along said scribe lines by pressing said scribe lines. The thickness of the second layer is smaller than the thickness of the third layer,
5. The cutting method according to claim 2, wherein cutting the substrate is performed by pushing the substrate from the second layer side. 6. The method according to any one of claims 1 to 5, wherein in the step of forming the scribe line, the scribe line is formed by irradiating a layer on which the scribe line is to be formed with a laser beam having a pulse width on the order of picoseconds. The cutting method according to any one of the above. 8. The cutting method according to claim 7, wherein said laser light has a wavelength in the infrared region. The cutting method according to any one of claims 1 to 8, wherein said first layer is a silicon substrate. A method for manufacturing a substrate piece from a substrate having a first layer made of a semiconductor single crystal and a second layer made of glass formed on the first layer, the method comprising:
forming a scribe line only on the second layer;
cutting the substrate along the scribe lines;
A method of manufacturing a substrate piece comprising: The substrate has a third layer, which is a layer of glass, formed on the side of the first layer opposite to the side on which the second layer is formed,
11. The method of manufacturing a substrate piece according to claim 10, wherein said scribe lines are formed in said second layer and said third layer. A method for producing a substrate piece from a substrate having a first layer made of a layer having cleavability and a second layer being a layer having no cleavability formed on the first layer, the method comprising:
forming a scribe line only on the second layer;
cutting the substrate along the scribe lines;
A method of manufacturing a substrate piece comprising: the substrate has a non-cleavable third layer formed on the side of the first layer opposite to the side on which the second layer is formed;
13. The method of manufacturing a substrate piece according to claim 12, wherein said scribe lines are formed in said second layer and said third layer.

Images