JPH11243040A - Device and method for separating sample and manufacture of substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a substrate from breaking, when the laminated substrate is separated. SOLUTION: A laminated substrate 101 has the laminated structure of a first substrate 101a having small strength, a porous layer 101b used as the separating layer and a second substrate 101c having large strength. The side of the first substrate 101a is held by a substrate holding part 120 which has the holding surface of the large area. The side of the second substrate 101c is held by a substrate holding part 130 having the holding surface of a small area. When water is injected from an injection nozzle 102 and inserted into the porous layer 101b so as to separate the substrate 101, the first substrate 101a is not deflected, but the second substrate 101c is deflected. Therefore, while breakage of the first substrate 101a having a small strength is prevented, the discharging path of water is secured, and the separation can be made efficient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for separating a plate-shaped sample and a method for manufacturing a substrate. For example, a plate-shaped sample having a fragile layer therein is separated by the fragile layer. The present invention relates to a separation apparatus and a separation method suitable for the above, and a method for manufacturing a substrate to which the apparatus or the method is applied.

[0002]

2. Description of the Related Art As a substrate having a single-crystal Si layer on an insulating layer, there is a substrate (SOI substrate) having an SOI (silicon on insulator) structure. Devices using this SOI substrate have a number of advantages that cannot be achieved with a normal Si substrate. The advantages include, for example, the following. (1) Dielectric separation is easy and suitable for high integration. (2) Excellent radiation resistance. (3) The stray capacitance is small, and the operation speed of the element can be increased. (4) No well step is required. (5) Latch-up can be prevented. (6) A complete depletion type field effect transistor can be formed by thinning.

[0003] Since the SOI structure has various advantages as described above, research on a forming method thereof has been advanced in recent decades. As an SOI technology, an SOS (silico) method is known in which Si is heteroepitaxially grown on a single crystal sapphire substrate by a CVD (chemical vapor deposition) method.
n on sapphire) technology is known. Although this SOS technology has received a reputation as the most mature SOI technology, it generates a large number of crystal defects due to lattice mismatch at the interface between the Si layer and the underlying sapphire substrate, and the aluminum Si layer constituting the sapphire substrate Practical use has not been promoted due to reasons such as contamination of the substrate, cost of the substrate, and delay in increasing the area.

Following SOS technology, SIMOX (separa
tion by ion implanted oxygen) technology has emerged. With respect to the SIMOX technology, various methods have been attempted with the aim of reducing crystal defects and reducing manufacturing costs. As this method, a method of implanting oxygen ions into a substrate to form a buried oxide layer, bonding two wafers with an oxide film interposed therebetween, and polishing or etching one of the wafers to form a thin single-crystal Si layer A method of leaving on an oxide film, furthermore, hydrogen ions are implanted at a predetermined depth from the surface of the Si substrate on which the oxide film is formed, and after bonding with the other substrate, a thin film is formed on the oxide film by heat treatment or the like. A method of removing the bonded substrate (the other substrate) while leaving the single crystal Si layer, or the like can be given.

The present applicant has disclosed a new SOI technique in Japanese Patent Application Laid-Open No. Hei 5-21338. According to this technique, a first substrate in which a non-porous single-crystal layer (SiO ₂ ) is formed on a single-crystal semiconductor substrate in which a porous layer is formed is separated from an insulating layer (Si).
O ₂ ) is applied to the second substrate, the two substrates are separated by a porous layer, and the non-porous single crystal layer is transferred to the second substrate. This technique has excellent thickness uniformity of the SOI layer, can reduce the crystal defect density of the SOI layer, has good surface flatness of the SOI layer,
Eliminates the need for expensive special equipment
It is excellent in that an SOI substrate having an SOI film in the range of about Å to 10 μm can be manufactured by the same manufacturing apparatus.

[0006] Further, the present applicant has disclosed in Japanese Patent Application Laid-open No. Hei 7-30288.
In No. 9, after the first substrate and the second substrate are bonded to each other, the first substrate is separated from the second substrate without breaking, and then the separated surface of the first substrate is removed. A technique has been disclosed in which a porous layer is formed again after smoothing and reused. This technique has excellent advantages that the first substrate can be used without waste, so that the manufacturing cost can be greatly reduced and the manufacturing process is simple.

[0007]

In the above technique, when a bonded substrate obtained by bonding a first substrate and a second substrate is separated into two, the substrate or the separated substrate is damaged. It is desired not to. The present invention has been made in view of the above circumstances, a separation apparatus and a separation method suitable for separating a plate-shaped sample represented by a substrate such as a bonded substrate, and a substrate to which the apparatus or the method is applied. It is intended to provide a manufacturing method.

[0008]

A separation device according to the present invention is a separation device for separating a plate-shaped sample, and a jetting unit for jetting a fluid for separating the sample toward the sample,
There are provided first and second holding portions for holding the sample so as to sandwich the sample from both sides, wherein the first and second holding portions have holding surfaces having different shapes from each other.

In the above-described separation apparatus, for example, the first holding portion may be configured so that one of the surfaces of the sample is relatively bent by the pressure of the fluid injected into the inside of the sample, and the other of the first holding portion is relatively small. Preferably, the surface is held, and the second holding portion holds the other surface of the sample such that the amount of deflection of the other surface of the sample due to the pressure of the fluid becomes relatively large. In the above-described separation device, for example, the first holding unit holds the one surface of the sample so as not to bend by the pressure of a fluid injected into the inside of the sample, The second holding unit preferably holds the other surface of the sample such that the other surface of the sample is bent by the pressure of the fluid.

In the above separating apparatus, for example, the holding surface of the first holding portion and the holding surface of the second holding portion preferably have different areas. In the above separation apparatus, for example, the first holding unit has a holding surface that holds the entire surface of one surface of the sample, and the second holding unit includes a part of the other surface of the sample. It is preferable to have a holding surface for holding.

In the above separating apparatus, for example, it is preferable that the holding surface of the first holding portion is formed as a flat surface. In the above-described separation device, for example, it is preferable that the holding surface of the first holding unit is formed of a curved surface. In the above-described separation device, for example, it is preferable that the holding surface of the second holding unit has an annular shape.

In the above-mentioned separation apparatus, for example, it is preferable that the second holding section has a plurality of projecting members, and holds the sample at the tips of the plurality of projecting members. In the above-described separation apparatus, for example, the second holding portion bends such that a central portion of a surface of the sample on the second holding portion side expands due to a pressure of a fluid injected into a sample. It is preferable to have a shape that allows this.

In the above separating apparatus, for example, the second holding portion may bend so that the surface of the sample on the second holding portion side is wavy due to the pressure of the fluid injected into the sample. Preferably. In the above separation apparatus, it is preferable that a rotation mechanism that rotates the sample by rotating at least one of the first and second holding units around an axis perpendicular to the holding surface is preferable.

The sample to be processed by the above separation apparatus is
For example, it is preferable that the first and second substrates have different strengths from each other when the first and second substrates are bonded to each other. The separation method according to the present invention is a separation method for separating a plate-shaped sample, holding the sample so as to sandwich both sides by a pair of holding portions having different holding surface shapes, in the thickness direction of the sample. The sample is separated by ejecting a fluid toward a predetermined position.

[0015] In the above separation method, the sample to be separated has a fragile layer inside, and when separating the sample, it is preferable to jet a fluid toward the fragile layer. The separation method according to the present invention is a separation method for separating a plate-shaped sample having a fragile layer therein by the fragile layer, and injecting a fluid toward the fragile layer of the sample to form the sample. A separating step of separating, and in the separating step, with respect to one surface of the sample, the other side of the sample is so reduced that the amount of deflection caused by the pressure of the fluid injected into the sample is relatively small. As for the surface, the sample is held so that the amount of deflection caused by the pressure of the fluid injected into the sample becomes relatively large.

The separation method according to the present invention is a separation method for separating a plate-shaped sample having a fragile layer therein by the fragile layer, by jetting a fluid toward the fragile layer of the sample. A separation step of separating the sample, wherein in the separation step, the other surface of the sample is limited with respect to one surface of the sample so as to limit deflection due to pressure of a fluid injected into the sample. The method is characterized in that the sample is held so as to allow bending due to the pressure of the fluid injected into the sample.

In each of the above separation methods, when the sample is separated by the fluid, it is preferable that the sample is rotated about an axis perpendicular to the main surface. The sample to be processed by the above-described separation method is, for example, a sample obtained by bonding first and second substrates, and the first and second substrates preferably have different strengths.

According to the separation method of the present invention, a composite substrate having a fragile layer between a first substrate having a relatively low strength and a second substrate having a relatively high strength is separated by the fragile layer. A separating method for separating the composite substrate by injecting a fluid toward the fragile layer, wherein in the separating step, regarding the first substrate,
With respect to the second substrate, the amount of deflection due to the pressure of the fluid injected into the composite substrate is relatively small so that the amount of deflection due to the pressure of the fluid injected into the composite substrate is relatively small. The composite substrate is held so as to be larger.

According to the separation method of the present invention, a composite substrate having a fragile layer between a first substrate having a relatively low strength and a second substrate having a relatively high strength is separated by the fragile layer. A separating method for separating the composite substrate by injecting a fluid toward the fragile layer, wherein in the separating step, regarding the first substrate,
Limiting the deflection due to the pressure of the fluid injected into the composite substrate, and regarding the second substrate, the composite substrate is allowed to bend due to the pressure of the fluid injected into the composite substrate. It is characterized by holding.

The method for manufacturing a substrate according to the present invention comprises the steps of: bonding a non-porous layer side of a first substrate having a porous layer and a non-porous layer formed on one surface in that order to a second substrate; A separation step of separating the bonded substrates by the porous layer, wherein the separation step,
It is characterized by using any one of the separation devices described above.

The method of manufacturing a substrate according to the present invention comprises the steps of: bonding a non-porous layer side of a first substrate having a porous layer and a non-porous layer formed on one surface in that order to a second substrate; A separating step of separating the bonded substrates by the porous layer, wherein the separating step is performed by applying any one of the above-described separating methods.

A holding device according to the present invention is a holding device for holding a sample when separating the sample by injecting a fluid toward a predetermined position in a thickness direction of the plate-shaped sample. The present invention is characterized in that the sample is held so as to sandwich both sides by a pair of holding portions having different shapes of holding surfaces for holding the sample.

[0023]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a view for explaining a method of manufacturing an SOI substrate according to a preferred embodiment of the present invention in the order of steps. In the step shown in FIG. 1A, a single-crystal Si substrate 11 is prepared, and a porous Si layer 12 is formed on the surface thereof by anodization or the like. Next, in a step shown in FIG. 1B, a single-crystal Si layer 13 which is a non-porous layer is formed on the porous Si layer 12 by an epitaxial growth method, and then the surface of the single-crystal Si layer 13 is oxidized. To form an SiO ₂ layer 15. Thereby, a first substrate () is formed.

In the step shown in FIG. 1C, a single-crystal Si substrate 14 is prepared as a second substrate (), and the SiO ₂ layer 15 of the first substrate () and the second substrate () are Then, the first substrate () and the second substrate () are brought into close contact with each other at room temperature. After that, the first substrate () and the second substrate () are bonded to each other by anodic bonding, pressing, heat treatment, or a combination thereof. With this process,
The second substrate () and the SiO ₂ layer 15 are firmly bonded. The SiO ₂ layer 15 is made of single crystal Si as described above.
It may be formed on the substrate 11 side, may be formed on the second substrate (), may be formed on both, and as a result,
When the first substrate and the second substrate are brought into close contact with each other, FIG.
The state shown in FIG.

In the step shown in FIG. 1D, the two bonded substrates are separated at the porous Si layer 12. Thereby, the second substrate side ("+") has a laminated structure of the porous Si layer 12 "/ the single-crystal Si layer 13 / the insulating layer 15 / the single-crystal Si substrate 14. On the other hand, on the first substrate side (')
Has a structure having a porous Si layer 12 ′ on a single-crystal Si substrate 11.

The separated substrate (') is formed by removing the remaining porous Si layer 12' and, if necessary, flattening the surface thereof to form the first substrate () again. Used as a single crystal Si substrate 11. After the bonded substrates are separated, in the step shown in FIG.
The porous layer 12 '' on the substrate side ("+") is selectively removed. Thereby, the single crystal Si layer 13 / insulating layer 1
5 / Laminated structure of single crystal Si substrate 14, ie, SOI
A substrate having a structure is obtained.

As the second substrate, for example, single crystal Si
In addition to the substrate, an insulating substrate (for example, a quartz substrate) and a light-transmitting substrate (for example, a quartz substrate) are suitable. In this embodiment, a porous layer 12 having a fragile structure is formed in a separation region in order to facilitate a process of separating two substrates after they are bonded to each other, but instead of this porous layer, For example, a microbubble layer may be formed. The microbubble layer can be formed, for example, by implanting ions into a semiconductor substrate.

The substrate manufactured by the above manufacturing method can be applied not only to the manufacture of semiconductor devices but also to the manufacture of fine structures. In this embodiment, the process shown in FIG.
In a step of separating two substrates (hereinafter, a bonded substrate), a high-pressure liquid or gas (fluid) is jetted to a porous Si layer which is a separation region to separate the substrate into two in the separation region. Use a separation device.

[Basic Configuration of Separation Apparatus]
The water jet method was applied. In general,
In the water jet method, water is jetted onto a target in a high-speed, high-pressure bundle flow, and ceramics, metal,
This method involves cutting and processing concrete, resin, rubber, wood, etc., removing the coating film on the surface, and cleaning the surface (see “Water Jet” Vol. 1, No. 1, page 4).

This separation apparatus injects a high-speed, high-pressure fluid in a bundle-like flow in the surface direction of the substrate onto the porous layer (separation region) of the bonded substrate, which is a fragile structure. The substrate is separated at the portion of the porous layer by selectively collapsing the porous layer. Hereinafter, this bundled flow is referred to as a “jet”. Further, the fluid constituting the jet is referred to as “jet constituting medium”. As the jet forming medium, for example, water is preferable.

When this separation apparatus is applied to the manufacture of a semiconductor substrate such as the above-mentioned SOI substrate, the water as the jet constituting medium is preferably pure water or ultrapure water from which impurity metals, particles and the like have been removed as much as possible. However, low-purity water can be used as a jet forming medium if the substrate is washed after being separated. Further, the jet constituting medium is not limited to water, for example, organic solvents such as alcohol, hydrofluoric acid, nitric acid and other acids, potassium hydroxide and other alkalis, air, nitrogen gas, carbon dioxide gas, rare gas, etching gas and other gases. It may be gas or plasma.

This separation device removes the porous layer from the outer peripheral portion toward the central portion by jetting a jet toward the porous layer (separation region) exposed on the side surface of the bonded substrate. As a result, the bonded substrate is separated into two substrates without damaging the main body portion, removing only the separation region having weak mechanical strength.
Note that even when the side surface of the bonded substrate is covered with some thin layer and the porous layer is not exposed, the layer is removed by jetting, and thereafter, the bonding is performed in the same manner as described above. The mating substrate can be separated.

It is preferable that there is a V (concave) groove along the circumferential direction at the outer peripheral portion of the bonded substrate. FIG.
It is a figure which shows notionally the force which acts on a bonding substrate.
FIG. 2A shows a bonded substrate having a V-shaped groove 22,
FIG. 2B shows a bonded substrate having no V-shaped groove. As shown in FIG. 2A, in the bonded substrate having the V-shaped groove 22, a force (hereinafter, separation force) is applied from the inside to the outside of the bonded substrate as indicated by an arrow 23. On the other hand, as shown in FIG. 2B, in a bonded substrate having a convex outer peripheral portion, a force is applied from the outside to the inside of the bonded substrate as indicated by an arrow 24. Therefore, in the bonded substrate whose outer peripheral portion has a convex shape, the separating force does not act unless the outer peripheral portion of the porous layer 12 which is the separation region is removed by the jet 21.

Further, even when a thin layer is formed on the surface of the outer peripheral portion of the bonded substrate, as shown in FIG. Since a separating force acts on the substrate, the layer can be easily broken. To use jet effectively, V
The width W1 of the opening of the mold groove 22 is equal to the diameter d of the jet 21.
It is preferable that it is equal to or more than the same. For example, each of the first substrate () and the second substrate () is 1 mm
Consider a case where the thickness of the bonded substrate is about 2 mm. Since the width W1 of the opening of the V-shaped groove 22 is generally about 1 mm, the diameter of the jet is preferably 1 mm or less. Since a jet having a diameter of about 0.1 to 0.5 mm is used in a general water jet device, such a general water jet device (for example, a water jet nozzle) can be used. .

Here, as the shape of the nozzle for jetting the jet, various shapes other than a circle can be adopted. For example, by adopting a slit-shaped nozzle and jetting a jet having an elongated rectangular cross section, the jet can be efficiently inserted (inserted between two substrates) into the separation region. The jet ejection conditions may be determined according to, for example, the type of the separation region (for example, the porous layer), the shape of the outer peripheral portion of the bonded substrate, and the like. The jet ejection conditions include, for example, the pressure applied to the jet constituting medium, the scanning speed of the jet, the width or diameter of the nozzle (substantially the same as the diameter of the jet), the nozzle shape, the distance between the nozzle and the separation region, the flow rate of the jet constituting medium. Are important parameters.

The method of separating the bonded substrates includes, for example,
1) A method in which a jet is inserted parallel to the bonding surface in the vicinity of the bonding surface and the nozzle is scanned along the bonding surface, and 2) The nozzle is parallel to the bonding surface in the vicinity of the bonding surface. 3) a method in which a jet is inserted and a bonded substrate is scanned, and 3) a method in which a jet is inserted in parallel with the bonding surface with respect to the vicinity of the bonding surface and the jet is scanned in a fan shape with the nozzle vicinity as a hip. 4)
A method in which a jet is inserted in the vicinity of the bonding surface in parallel with the bonding surface and the bonded substrate is rotated about the center of the bonded substrate as an axis (particularly effective when the bonded substrate has a disk shape). ). Note that the jet does not necessarily need to be jetted completely parallel to the bonding surface.

The bonded substrate has a cutting force, that is, a breaking force, which is a force acting in a direction for expanding the bonded substrate, in addition to a destruction of the hole wall due to an impact force of a jet colliding with the hole wall of the porous layer. That is, the separation is caused by the destruction of the pore wall due to the pressure of the jet constituting medium injected into the porous layer. The axial separation force applied to the bonded substrate is preferably, for example, about several hundred gf per 1 cm 2 in order to prevent the substrate from being damaged.

In order to separate the bonded substrates using only the cutting force of the jet, it is necessary to jet the jet at a high pressure of, for example, 1000 kgf or more per square cm. When the bonded substrates are separated by such a high-pressure jet, there is a risk of damaging the substrates. The bonded substrate is, for example, 0.5 mm to 1.0 m
It is preferable to have a thickness of about m, but when such a thin bonded substrate is separated by a high-pressure jet, for example, if there is a locally strong portion of the porous layer,
There is also a risk that the pressure (separation force) of the jet suddenly increases and the substrate is broken because the discharge path of the jet constituent medium is not secured.

Therefore, for example, 500 k per square cm
It is preferable to use a jet having a low pressure of about gf to compensate for the shortage of the cutting force with the separating force. This method can prevent the substrate from being damaged at a considerable rate. However, in order to further prevent damage to the substrate, it is preferable to consider the shape and characteristics of the member to be separated. For example, when the bonded substrate is separated into the first substrate side (') and the second substrate side ("+") as described above, the shapes and characteristics (particularly strength) of both substrates are taken into consideration. It is preferable to optimize the method of holding the bonded substrate at the time of separation. That is, since the first substrate () is formed through various processes (including a high-temperature process) such as anodization, formation of an epitaxial layer, and oxidation, the first substrate () is more easily broken than the second substrate (). there is a possibility. After removing the porous layer remaining on the surface on the first substrate side after the separation, the porous layer is again removed from the first substrate.
When used as (), the first substrate is a single SO
Each time the I-substrate is manufactured, it becomes thinner, for example, by about 30 μm. Therefore, as the number of reuses increases, the risk of cracking during the separation process increases.

In this embodiment, among the members to be separated, those having a small strength and being easily cracked are prevented from cracking by reducing the amount of deflection due to the separation force by the jet, while having a large strength and hard to crack. On the member side, there is disclosed a separation device that increases the amount of deflection caused by the separation force of the jet to increase the efficiency of discharging the jet constituent medium from the separation region (inside the member).

[Structural Example of Separating Apparatus] FIGS. 3 to 5
A specific configuration example of the separation device according to the preferred embodiment of the present invention will be described with reference to FIG. The separation device according to this configuration example is suitable for separating a bonded substrate having a porous layer or a microbubble layer which is a fragile structure inside, but other members having a fragile structure inside. Can also be used for the separation of In this case, it goes without saying that the components of the separation device should be appropriately changed according to the shape of the member to be separated.

FIG. 3 is a diagram schematically showing a configuration of a separation apparatus according to a preferred embodiment of the present invention. FIG. 4 shows FIG.
It is a perspective view of a part of separation device shown in FIG. FIG. 5 is a diagram schematically illustrating a state of the separation processing. This separation device 100
Is provided with substrate holding units 120 and 130 having a vacuum suction mechanism, and holds the bonded substrate 101 by sandwiching the bonded substrate 101 from both sides. One substrate holding part 120 has a structure that contacts the bonded substrate 101 with a large area, and the other substrate holding part 130 has a structure that contacts the bonded substrate 101 with a small area. In these structures, one side of the bonded substrate 101 is configured such that the amount of bending during the separation processing is reduced or does not occur, and the other side is configured such that the amount of bending during the separation processing is relatively small. This is an example of a structure for increasing the size of the image.

The bonded substrate 101 has a porous layer 101b, which is a fragile structure, inside.
0, the first substrate 101 in the portion of the porous layer 101b
a and the second substrate 101c. Here, the first
Substrate 101a corresponds to the above-mentioned first substrate side ('), and the second substrate 101c corresponds to the above-mentioned second substrate side (').
+).

As described above, the first substrate 101a is formed through various processes (including a high-temperature process) such as anodization, formation of an epitaxial layer, and oxidation, and therefore, compared to the second substrate 101c. Easy to crack. Therefore, by holding the first substrate 101a side of the bonded substrate 101 with the substrate holding portion 120 having a large-area holding surface,
Deflection of the first substrate 101a during the separation processing can be limited to prevent cracking. On the other hand, the second substrate 101c
Is relatively stronger than the first substrate 101a, and can withstand a corresponding bending. Therefore, the second substrate 101c is connected to the substrate holding portion 13 having a small-area holding surface.
By holding at 0, it is possible to allow a certain amount of bending during the separation process, thereby allowing the jet medium injected between the substrates 101a and 101c to be efficiently discharged, and as a result, the separation process can be efficiently performed. Can be

The substrate holding unit 120 includes a rotating shaft 10 rotatably supported on a support 109 via a bearing 108.
4, and the other end of the rotating shaft 104 is connected to the rotating shaft of the motor 110. Therefore, the rotational force generated by the motor 110 causes the bonded substrate 101
Will be rotated. The motor 110 rotates the rotating shaft 104 at a designated rotation speed according to a command from a controller (not shown).

The substrate holding section 130 has a rotating shaft 103 which is slidably and rotatably supported via a bearing 111.
And the other end of the rotating shaft 103 is connected to an air cylinder 112 fixed to a support 109. When the air cylinder 112 pushes the rotating shaft 103, the bonded substrate 101 is pressed by the substrate holding unit 130.

In order to limit the amount of bending of the first substrate 101a as much as possible, the diameter of the suction surface of the substrate holding unit 120 is adjusted so that the entire surface of the first substrate 101a can be supported. It is preferable that the suction surface is made equal to or more than that and the suction surface is formed of a flat surface. However, the shape of the suction surface of the substrate holding unit 120 is not limited to this, and may be, for example, a curved surface such as a spherical surface or an area smaller than the bonded substrate 101. That is, the shape of the suction surface of the substrate holding unit 120 may be determined according to the amount of bending that the first substrate 101a can tolerate.

On the other hand, the substrate holding section 130 holds the second substrate 1
The amount of flexure of the second substrate 101c may be determined so that the amount of flexure of the first substrate 101c is relatively larger than the amount of flexure of the first substrate 101a. The substrate holding units 120 and 130 exist on the same rotation axis. Further, the substrate holders 120 and 130 are respectively provided with rotating shafts 104 and 103, respectively.
It is possible to remove from. Further, the substrate holding unit 12
On the holding surfaces 0 and 130, grooves for vacuum suction are formed, and these grooves communicate with the vacuum lines passing through the insides of the rotating shafts 104 and 103, respectively. The vacuum line is connected to an external vacuum line via, for example, a rotary vacuum joint. A solenoid valve is attached to the external vacuum line, and by controlling the solenoid valve, the attachment and detachment of the substrate can be controlled.

Hereinafter, the separation processing of the substrate by the separation apparatus 100 will be described. In order to set the bonded substrate 101 in the separation processing 100, first, the rotating shaft 103 is housed in the air cylinder 112, so that an appropriate distance is provided between the holding surfaces of the substrate holding units 120 and 130. Next, after the bonded substrate 101 is placed on the positioning shaft 113, the rotating shaft 103 is attached to the air cylinder 112.
Are pushed out to press and hold the bonded substrate 101 (the state shown in FIG. 3). The positioning shaft 113 is rotatably supported by bearings 105 and 107.

In this embodiment, the bonded substrate 10
1 is held not by vacuum suction but by the pressing force of the air cylinder 112. For example, the pressing force is 3kgf
The degree is preferred. However, it is of course possible to hold the bonded substrate 101 by vacuum suction. Next, a jet forming medium (for example, water) is sent from the pump 114 to the injection nozzle 102, and waits until the jet injected from the injection nozzle 102 is stabilized. When the jet is stabilized, the shutter 106 is opened and the bonded substrate 101 is opened.
And the motor 1
10 rotates the bonded substrate 101. At this time, the rotating shaft 104, the substrate holding unit 120, the bonded substrate 101, the substrate holding unit 130, and the rotating shaft 103 rotate integrally. Note that the injection nozzle 102 is attached to a position adjustment mechanism (for example, an XY stage), and the position at which the jet is inserted into the bonded substrate 101 can be adjusted by the position adjustment mechanism.

When the jet is sandwiched, a separation force due to the pressure of the jet forming medium continuously injected into the porous layer 101b, which is a fragile structure, acts on the bonded substrate 101. The porous layer 101b connecting 101a and 101c is broken. At this time, the substrate 1
01a and 101c bend within the range permitted by the substrate holders 120 and 130, respectively. In this separation apparatus 100, the amount of deflection of the substrate 101a is relatively small, and
The deflection amount of 1c is relatively large.

By this processing, the bonded substrate 101
Is separated into two substrates 101a and 101c in about two minutes, for example. When the bonded substrate 101 is separated into two substrates, the shutter 106 is closed and the pump 114 is closed.
Stop the operation of. In addition, the rotation of the motor 110 is stopped, and the separated substrates 101a and 101c are vacuum-adsorbed to the substrate holding units 120 and 130 by controlling the above-described electromagnetic valve.

Next, the rotary shaft 103 is attached to the air cylinder 112.
Is accommodated, the two physically separated substrates 1
01a and 101c are jet constituting media (for example, water)
The surface tension is cut off and the two are separated. Next, modified examples of the substrate holding unit of the separation device 100 will be described. [Modification 1] A separation apparatus according to this modification is obtained by replacing the substrate holding units 120 and 130 of the separation apparatus 100 shown in FIGS. FIG. 6 is a diagram showing a schematic configuration of a separation device 100 'according to this modification.

In the separation apparatus 100 ', the substrate holding unit 1
At 20, the first substrate 101a side of the bonded substrate 101 is held, and at the substrate holding section 130, the second substrate 101c side is held. That is, in the separation device 100 ′, the second substrate 10 is placed on the rotation shaft 104 side where the horizontal position is fixed.
The bonded substrate 101 is held so that the side 1c is positioned.

The separating apparatus 100 'converts the separated first substrate 101a into a porous layer 101b remaining on its surface.
Is suitable for the case where is removed and reused as the first substrate (). The reason is as follows. First substrate 10
When reusing 1a, the thickness of the first substrate 101a is reduced according to the number of times of reuse. Therefore, in the separation apparatus 100 shown in FIG. 3, in order to perform the separation processing more efficiently and properly, the injection nozzle 102 is required every time the separation processing is performed.
Need to be located directly above the separation region of the bonded substrate 101. If the position of the injection nozzle 102 is fixed, the jet is not pinched at the center of the porous layer 101b, and there is a risk of damaging the substrates 101a and 101c.

On the other hand, the separation device 100 ′ according to this modification example
Then, if the bonded substrate 101 having a constant thickness of the second substrate 101c is processed, the positional relationship between the porous layer 101b and the injection nozzle 102 is changed even when the position of the injection nozzle 101b is fixed. Never be.
This is because the position of the substrate holding unit 130 is fixed, and the second substrate 101 held by the substrate holding unit 130 is fixed.
This is because the thickness of c is constant.

[Modification 2] This modification is shown in FIGS.
Is a modification of the structure of each substrate holder of the separation apparatus 100 shown in FIG. FIG. 7 is a diagram illustrating a schematic configuration of a substrate holding unit of a separation device according to this modification. In this separation device,
The first substrate 101a side of the bonded substrate 101 is held by the substrate holding portion 121 having a substantially circular suction surface, and the second substrate of the bonded substrate 101 is held by the substrate holding portion 131 having a substantially annular suction surface. Hold the 101c side.

The substrate holders 121 and 13 according to this modification example
1 is the amount of deflection of the first substrate 101a and the second substrate 10
The amount of flexure of 1c is limited to the range of the amount of flexure allowed, thereby preventing the substrates 101a and 101c from being damaged and increasing the efficiency of the separation process. Since the diameter of the substrate holding portion 121 is smaller than that of the bonded substrate 101, the first substrate 101a bends so that the outer peripheral portion is warped during the separation processing. The holding surface of the substrate holding unit 121 may be, for example, a flat surface or a curved surface such as a spherical surface. On the other hand, since the holding surface of the substrate holding portion 131 has an annular shape, the substrate 101c is located near the suction surface (see FIG.
1, 702), and bends in a wavy manner with the outer periphery and the center as antinodes. As described above, the substrate holding portions 121 and 13 having a shape that can bend so that the second substrate 101c undulates.
By employing 1, the jet constituting medium injected into the bonded substrate 101 can be efficiently discharged.

When the separation process was performed by this separation apparatus, after the jet was sandwiched between the bonded substrates 101, the jet advanced to the vicinity of the holding surface of the substrate holding portion 131 (701 in FIG. 7) in about 30 seconds. Thereafter, after about 30 seconds, the jet advanced to the vicinity of the holding surface on the opposite side (702 in FIG. 7), and as shown in FIG. 7, the substrate 101c was bent in a wavy manner. Then, the bonded substrate 101 takes 2 minutes in about 3 minutes.
It was separated into pieces.

In the separation process of the bonded substrate 101, since the jet constituting medium is hardly discharged at the central portion, the pressure of the jet constituting medium is likely to increase, and the possibility of breakage is higher than that of the peripheral portion. Therefore, like the substrate holding part according to this modification, the second substrate 101c having high strength is used.
Only, the central portion expands toward the substrate holding portion 131 and is allowed to bend to prevent the first substrate 101a having low strength from being damaged, while securing a discharge path of the jet forming medium. can do.

[Modification 3] This modification is shown in FIGS.
The structure of each of the substrate holders 120 and 130 of the separation apparatus 100 shown in FIG. FIG. 8 is a diagram illustrating a modified example of the substrate holding unit 120 that holds the first substrate side. FIG. 9 shows a substrate holding unit 130 that holds the second substrate side.
It is a figure which shows the modification of.

As shown in FIG. 8, the diameter of the substrate holding portion 122 for holding the first substrate 101a is slightly smaller than the diameter of the bonded substrate 101, and its suction surface is, for example, a flat surface. I have. Therefore, the first substrate 1
01a is bent so that the outer peripheral portion is warped during the separation process. On the other hand, as shown in FIG. 9, the substrate holding unit 132 has a plurality of protrusion-shaped suction portions 132a.
The second substrate 101c side of the bonded substrate 101 is held by the distal end portion 32a. By holding the second substrate 101c side by the protruding suction portion 132a in this manner, the second substrate 101c is easily bent, and the jet constituent medium injected into the bonded substrate 101 is discharged. Can be made more efficient. In order to stably hold the bonded substrate 101, it is preferable that the number of the protrusion-shaped suction portions 132a is three or more.

Although the characteristic technical ideas have been described with reference to the specific embodiments, the present invention is not limited to the matters described in these embodiments.
Various modifications can be made within the scope of the technical idea described in the claims.

[0064]

According to the present invention, it is possible to efficiently perform a separation process while preventing damage to a sample such as a substrate.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a method for manufacturing an SOI substrate according to a preferred embodiment of the present invention in the order of steps.

FIG. 2 is a diagram conceptually showing a force acting on a bonded substrate.

FIG. 3 is a diagram schematically showing a configuration of a separation device according to a preferred embodiment of the present invention.

4 is a perspective view of a part of the separation device shown in FIG.

FIG. 5 is a diagram schematically showing a state of a separation process.

FIG. 6 is a diagram illustrating a schematic configuration of a separation device according to a first modification.

FIG. 7 is a diagram illustrating a schematic configuration of a substrate holding unit of a separation device according to a second modification.

FIG. 8 is a diagram illustrating a schematic configuration of a substrate holding unit (first substrate side) according to Modification Example 3.

FIG. 9 is a diagram illustrating a schematic configuration of a substrate holding unit (second substrate side) according to Modification Example 3.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Single-crystal Si substrate 12, 12 ', 12' 'Porous Si layer 13 Non-porous single-crystal Si layer 14 Single-crystal Si substrate 15 Insulating layer 100, 100' Separation apparatus 101 Bonded substrate 101a First substrate 101b Porous Material layer 101c Second substrate 102 Injection nozzle 103, 104 Rotation axis 105, 107 Bearing 106 Shutter 108, 109 Bearing 110 Motor 112 Air cylinder 113 Alignment axis 114 High pressure pump 120, 121, 122 Substrate holder 130, 131, 132 Substrate holding part 132a Suction part

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takao Yonehara 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (24)

[Claims] 1. A separating apparatus for separating a plate-shaped sample, comprising: a jetting unit for jetting a fluid for separating the sample toward the sample; and first and second holding units so as to sandwich the sample from both sides. And a holding unit, wherein the first and second holding units have holding surfaces having different shapes from each other. 2. The method according to claim 1, wherein the first holding unit holds the one surface of the sample such that a deflection amount of the one surface due to a pressure of a fluid injected into the sample is relatively small. Second
2. The separation device according to claim 1, wherein the holding unit holds the other surface of the sample such that a deflection amount of the other surface of the sample due to a pressure of the fluid is relatively large. 3. The first holding unit holds one surface of the sample so that the one surface of the sample is not bent by the pressure of a fluid injected into the inside of the sample, and the second holding unit holds the second surface of the sample. 2. The holding unit according to claim 1, wherein the holding unit holds the other surface of the sample such that the other surface of the sample is bent by the pressure of the fluid.
The separation device according to claim 1. 4. The holding surface of the first holding portion and the holding surface of the second holding portion have different areas from each other. Separation equipment. 5. The first holding portion has a holding surface for holding the entire surface of one surface of the sample, and the second holding portion has a holding surface for holding a part of the other surface of the sample. The separation device according to any one of claims 1 to 4, wherein the separation device has a surface. 6. The separation device according to claim 1, wherein the holding surface of the first holding unit is formed as a flat surface. 7. The separation device according to claim 1, wherein the holding surface of the first holding unit is formed of a curved surface. 8. The apparatus according to claim 1, wherein the holding surface of the second holding portion has an annular shape.
The separation device according to Item. 9. The apparatus according to claim 1, wherein the second holding section has a plurality of projecting members, and holds the sample at a tip end of the plurality of projecting members. The separation device according to claim 1. 10. The second holding portion allows a central portion of a surface of the sample on the side of the second holding portion to expand due to a pressure of a fluid injected into the inside of the sample so as to bend. The separation device according to any one of claims 1 to 7, wherein the separation device has a shape that changes. 11. The second holding portion has a shape that allows the surface of the sample on the side of the second holding portion to undulate and bend by the pressure of the fluid injected into the sample. The method according to claim 1, wherein:
The separation device according to Item. 12. The apparatus according to claim 1, further comprising a rotation mechanism configured to rotate a sample by rotating at least one of the first and second holding units around an axis perpendicular to a holding surface. Item 12. The separation device according to any one of items 11 to 12. 13. A sample to be processed is a substrate obtained by bonding first and second substrates, wherein the first and second substrates are bonded.
2. The substrate according to claim 1, wherein the substrates have different strengths.
The separation device according to claim 12. 14. A separation method for separating a plate-shaped sample, wherein the sample is held by a pair of holding portions having different holding surfaces so as to sandwich both sides, and the sample is held at a predetermined position in the thickness direction of the sample. Separating the sample by ejecting a fluid toward the sample. 15. The sample according to claim 14, wherein the sample to be separated has a fragile layer inside, and when separating the sample, a fluid is jetted toward the fragile layer. Separation method. 16. A separation method for separating a plate-shaped sample having a fragile layer therein by the fragile layer, wherein the separation is performed by jetting a fluid toward the fragile layer of the sample. Having a step, in the separation step, with respect to one surface of the sample, so that the amount of deflection due to the pressure of the fluid injected into the sample is relatively small,
A separation method characterized by holding the sample such that the other surface of the sample is relatively bent by the pressure of the fluid injected into the sample, due to the pressure. 17. A separation method for separating a plate-shaped sample having a fragile layer therein by the fragile layer, wherein the separation is performed by jetting a fluid toward the fragile layer of the sample. A step of separating the sample with respect to the other surface of the sample in the separation step so as to limit deflection due to pressure of a fluid injected into the sample with respect to one surface of the sample. A separation method, comprising: holding the sample so as to allow deflection of the fluid injected therein due to pressure. 18. The separation according to claim 14, wherein when the sample is separated by a fluid, the sample is rotated around an axis perpendicular to the main surface thereof. Method. 19. A sample to be processed is a sample obtained by bonding first and second substrates, and wherein the first and second substrates are bonded together.
2. The substrate according to claim 1, wherein the substrates have different strengths.
The separation method according to any one of claims 4 to 18. 20. A separation method for separating a composite substrate having a fragile layer between a first substrate having a relatively low bending strength and a second substrate having a relatively high strength by the fragile layer. A separating step of separating the composite substrate by injecting a fluid toward the fragile layer, wherein in the separating step, the first substrate is injected into the composite substrate. As for the second substrate, the composite substrate is formed such that the amount of deflection caused by the pressure of the fluid injected into the interior of the composite substrate is relatively large so that the amount of deflection caused by the pressure of the fluid is relatively small. A separation method comprising: 21. A separation method for separating a composite substrate having a fragile layer between a first substrate having a relatively low strength and a second substrate having a relatively high strength, using the fragile layer. A separating step of separating the composite substrate by injecting a fluid toward the fragile layer, wherein in the separating step, for the first substrate, a fluid injected into the composite substrate is A separation method, comprising: limiting bending due to pressure, and holding the composite substrate such that the second substrate is allowed to bend due to pressure of a fluid injected into the composite substrate. 22. A step of bonding the non-porous layer side of a first substrate, on which a porous layer and a non-porous layer are sequentially formed on one surface, to a second substrate; 13. A method for manufacturing a substrate, comprising: a separation step of separating a substrate by a porous layer, wherein in the separation step, the separation device according to claim 1 is used. Production method. 23. A step of bonding the non-porous layer side of a first substrate, on which a porous layer and a non-porous layer are sequentially formed on one surface, to a second substrate; 19. A method for manufacturing a substrate, comprising: a separation step of separating a substrate by a porous layer, wherein the separation step is performed by applying the separation method according to any one of claims 14 to 18. Substrate manufacturing method. 24. A holding device for holding a sample when separating the sample by injecting a fluid toward a predetermined position in a thickness direction of a plate-shaped sample, the holding surface holding the sample. A holding device for holding the sample by sandwiching both sides between a pair of holding portions having different shapes.