JPH1145840A - Method for separating composite member, separated member, separator, and manufacture of semiconductor base - Google Patents

Abstract

PROBLEM TO BE SOLVED: To separate a composite member by a method, wherein a fluid is sprayed to a recess type of the composite member or a side face having a narrow gas. SOLUTION: A first member 1 has a separation area 3 which is to became a separation portion therein. This layered separation region 3 is weaker in mechanical strength than that of a layer region 5 on the side of a joint face 4a. Two members 1, 2 joint joint faces 4a, 4b which face counter to each other to form a discoidal composite member having a joint interface 14. A fluid 7 is ejected towards an end part of the separation region 3 on a side face 6 of this composite member from a nozzle 8, and spayed. The separation region 3 in which the fluid 7 is sprayed or collapsed. Thus, the composite member is separated into two member 11, 12 with the separation region 3 as a border. A layered region 5 no longer existed on a separation face 13a of the separated one member 11 and is transferred onto the joint face 4b of the original second member 2 so as to expose a separation face 13b. Thus, a member having the layered region 5 on the second member 2 is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for separating a composite member, a separating device, a separated member, a semiconductor substrate, and a method for manufacturing the same.

[0002]

2. Description of the Related Art The formation of a single-crystal Si semiconductor layer on an insulating surface of a substrate is widely known as a semiconductor-on-insulator (SOI) technique, and cannot be achieved with a bulk Si substrate for fabricating a normal Si integrated circuit. Much research has been done because devices utilizing SOI technology have numerous advantages. That is, by using the SOI technology, (1) dielectric isolation is facilitated and high integration is possible, (2) radiation resistance is excellent, (3) stray capacitance is reduced and high speed is possible, (4) a well formation step can be omitted; (5) latch-up can be prevented;
(6) An advantage such as realization of a fully depleted field effect transistor can be realized by thinning.

[0003] In order to realize many of the above advantages in device characteristics, researches have been made on a method of forming an SOI structure for several decades. In the old days, CVD (chemical vapor deposition) of Si on a single crystal sapphire substrate
SOS (silicon on sapphire) is known to be formed by heteroepitaxy, and although it has achieved some success as the most mature SOI technology, a large amount of crystal due to lattice mismatch between the Si layer and the underlying sapphire substrate. Defects, the incorporation of aluminum from the sapphire substrate into the Si layer, and most of all, the delay in increasing the cost and area of the substrate has hindered its application. In recent years, attempts have been made to realize an SOI structure without using a sapphire substrate. This attempt is roughly divided into the following two.

[0004] 1. After oxidizing the surface of the Si single crystal substrate,
A window is opened in the oxide film to partially expose the Si substrate, and that portion is epitaxially grown laterally as a seed,
Form a Si single crystal layer on SiO ₂ (in this case,
With the deposition of a Si layer on SiO ₂ ).

[0005] 2. The Si single crystal substrate itself is used as an active layer, and SiO ₂ is formed thereunder (this method does not involve the deposition of a Si layer).

Means for achieving the above 1 include a method of directly growing a single crystal layer Si in the lateral direction by CVD, a method of depositing amorphous Si and performing a solid-phase lateral epitaxial growth by heat treatment, ,
An energy beam such as an electron beam or a laser beam is converged and irradiated onto the polycrystalline Si layer, and the single crystal layer is melted and recrystallized to form a Si crystal.
A method of growing on O ₂ , and a method of scanning a molten region in a band shape by a rod-shaped heater (Zone Melti)
ing Recycling) is known. Although each of these methods has advantages and disadvantages, it still has significant problems in controllability, productivity, uniformity, and quality, and there is no industrially practical method yet. For example, in the CVD method, sacrificial oxidation is required to make the thin film flat. Crystallinity obtained by the solid phase growth method is poor. Further, the beam annealing method has a problem in controllability such as processing time by convergent beam scanning, beam overlap, focus adjustment, and the like. Among them, Zone Meltii
Although the ng recrystallization method is the most mature and relatively large-scale integrated circuits have been prototyped, a large number of crystal defects such as sub-grain boundaries still remain, which is sufficient to produce a minority carrier device. High quality crystals have not been obtained.

[0007] In the above method 2 in which the Si substrate is not used as a seed for epitaxial growth, the following 4 methods are used.
There are different methods.

(1) An oxide film is formed on a Si single crystal substrate having a V-shaped groove anisotropically etched on its surface, and a polycrystalline Si layer is deposited on the oxide film as thick as the Si substrate. Si
Polishing from the back side of the substrate, V
A dielectrically separated Si single crystal region surrounded by the groove is formed. In this method, the crystallinity is good, but the step of depositing polycrystalline Si to a thickness of several hundred microns is called single crystal Si.
There is a problem from the viewpoint of controllability and productivity in the step of polishing the substrate from the back surface to leave only the separated Si active layer.

(2) SIMOX: Sepox
eration by Ion Implanted
Oxygen) is a method of forming an SiO ₂ layer by ion implantation of oxygen into a Si single crystal substrate.
Currently the most mature method due to its good consistency with the process. However, in order to form a SiO ₂ layer, it is necessary to implant oxygen ions of 10 ¹⁸ ions / cm ² or more. However, the implantation time is long and the productivity is not high. Cost is high. Furthermore,
Many crystal defects remain, and are not of sufficient quality to produce a minority carrier device industrially.

(3) A method of forming an SOI structure by dielectric isolation by oxidation of porous Si. This method uses P-type S
Proton ion implantation of an N-type Si layer on the surface of an i-single crystal substrate (Imai et al., J. Crystal Growth, Vo
163, 547 (1983)) or an island is formed by epitaxial growth and patterning, and only the P-type Si substrate is made porous by anodizing in an HF solution so as to surround the Si island from the surface. This is a method in which N-type Si islands are dielectrically separated by rapid oxidation. In this method,
The separated Si region is determined before the device process, and there is a problem that the degree of freedom in device design may be limited.

(4) A method of forming an SOI structure by bonding a Si single crystal substrate to another thermally oxidized Si single crystal substrate by using a heat treatment or an adhesive has attracted attention. This method requires that the active layer for the device be uniformly thinned. That is, it is necessary to reduce the thickness of a Si single crystal substrate having a thickness of several hundred microns to the order of microns or less.

There are two types of methods for reducing the thickness as follows.

1) Thinning by polishing 2) Thinning by selective etching It is difficult for the polishing of 1) to uniformly thin. In particular, when the thickness is reduced to a submicron, the variation becomes tens of percent, and the uniformity is a serious problem. Further, if the diameter of the substrate is increased, the difficulty will only increase.

The etching of 2) is said to be effective for uniform thinning, but the selectivity is not sufficient at most 10 ^2. The surface properties after etching are poor. Ion implantation, high concentration B-doped Si layer Since the above epitaxial growth or heteroepitaxial growth is used, there are problems such as poor crystallinity of the SOI layer.

Further, the semiconductor substrate using the bonding is
Inevitably, two substrates are required, and one of them is almost completely removed by polishing or etching and discarded, and wastes limited earth resources. Therefore, in SOI by lamination,
In the current method, there are many problems in controllability, uniformity, and economy.

On a light-transmitting substrate represented by glass, generally, the deposited thin-film Si layer is amorphous or amorphous, reflecting the disorder of the substrate, due to the disorder of its crystal structure. It is only a polycrystalline layer at best, and a high-performance device cannot be manufactured. This is due to the fact that the crystal structure of the substrate is amorphous, and even if a Si layer is simply deposited, a high-quality single crystal layer cannot be obtained. Incidentally, a light-transmitting substrate is important in manufacturing a contact sensor or a projection-type liquid crystal image display device as a light receiving element. And the pixels (picture elements) of sensors and display devices have been further densified,
Higher resolution and higher definition require not only improved pixels but also high-performance driving elements. As a result, a single crystal layer having excellent crystallinity is required even when an element is formed on a light transmitting substrate.

In such an SOI substrate manufacturing method, a non-single-crystal semiconductor layer is formed on a porous layer as disclosed in JP-A-5-21338, and this is transferred to a supporting substrate via an insulating layer. The method used is that the thickness of the SOI layer is excellent in uniformity, that the density of crystal defects in the SOI layer is easy to keep low, that the surface flatness of the SOI layer is good, and that an expensive special specification device is used in manufacturing. This is very excellent in that it does not need to be used, and that it can be manufactured with the same apparatus in a wide SOI film thickness range from several hundred angstroms to about 10 microns.

Further, the above method is disclosed in Japanese Patent Application Laid-Open No. 7-30288.
9, a non-porous single-crystal semiconductor layer is formed on the porous layer of a first substrate having a porous layer, and the non-porous single-crystal layer is formed on a second substrate. After laminating via an insulating layer, the first substrate and the second substrate in the porous layer are separated without breaking both,
The first substrate can be used many times by repeating the process of smoothing the surface of the first substrate, forming the porous material again, and reusing. Therefore, a great effect is obtained that the manufacturing cost can be greatly reduced and the manufacturing process itself can be simplified.

There are several methods for separating a bonded substrate that separates both the first substrate and the second substrate without breaking. For example, one is a method of pulling in a method perpendicular to the bonding surface. A method of applying a shearing stress in parallel to the bonding surface (for example, a method of moving the respective substrates in directions opposite to each other in a plane parallel to the bonding surface or a method of rotating the respective substrates in the circumferential direction in opposite directions) Method). Alternatively, a method of applying pressure in a direction perpendicular to the bonding surface may be used. Further, there is a method of applying wave energy such as ultrasonic waves to the separation region.
Alternatively, a method of inserting a peeling member (e.g., a sharp blade such as a knife) into the separation region from the side surface of the bonded substrate in parallel with the bonded surface may be used. Further, there is a method of utilizing the expansion energy of a substance impregnated in a porous layer functioning as a separation region. There is also a method in which a porous layer functioning as a separation region is thermally oxidized from the side surface of the bonded substrate to expand the volume, thereby separating the substrate. There is also a method in which a porous layer functioning as a separation region is selectively etched and separated from a side surface of a bonded substrate. Microcavities formed by ion implantation as separation regions
There is also a method of irradiating a laser from the normal direction of the bonding surface using a layer capable of obtaining the above and heating the separation region containing bubbles to perform separation.

[0020]

However, while the above-described method of separating two bonded substrates is ideally a good method, any method for realizing it is suitable for manufacturing a semiconductor substrate. Not necessarily. One of the major obstacles is that the bonded semiconductor substrates are generally disc-shaped (disk-shaped), and their thickness is as thin as about 0.5 to 1.0 mm, so that the jig can be hooked on the bonded portions. This means that there are very few relatively large dents. For this reason, a jig having a concave portion corresponding to the orientation flat portion (orientation flat) is used to hook the orientation flat portion of the base and rotate it in parallel with the bonding surface, or to make a slight concave portion in the bonding portion on the side surface of the bonded base.
There is a limit to using the method of hooking a jig and peeling it off. In the method of separation by pressurization, a very large pressure is required, so that the apparatus becomes large. In the case of the method using the wave energy, it is necessary to devise a method of irradiating the wave in order to efficiently irradiate the wave to the bonded substrates, and the separated substrates are required to be separated immediately after the separation. They can vibrate in partial contact and injure each other. In the method of separating from the side surface, only the side surface is peeled off due to bending of the base body, and the substrate may not be easily separated to the center. In the method in which the peeling member is inserted into the separation region from the side surface of the bonded substrate, the portion that was the bonding surface of the substrate may be damaged by friction between the peeling member and the substrate by inserting the peeling member.

In order to avoid such a problem, one solution may be to make the mechanical strength of the separation region considerably weak. However, in this case, the probability that the portion of the separation region is broken by an external impact before bonding the substrates is increased. In such a case, a part of the broken separation region may contaminate the inside of the manufacturing apparatus as particles. Each of the conventional separation methods has significant advantages,
The above issues still remain.

An object of the present invention is to separate the substrates without destroying the substrates themselves, not to damage the separated substrates, and to prevent the destruction of the separation region even before receiving an external impact before the step of separating the bonded substrates. It is another object of the present invention to provide a more excellent separation method and a separation apparatus which can prevent the contamination of the production apparatus by particles.

[0023]

According to the present invention, a composite member having a plurality of members joined to each other is separated into a plurality of members at a portion (separation region) different from a joining portion of the members by spraying a fluid. It is characterized by doing.

The term "composite member" as used herein means a member having a separation region therein, and any structure can be considered from the standpoint of the separation method. That is, the separation region is formed in a layer shape parallel to the surface at a portion deeper than the surface, and the surface and a portion shallower from the surface are formed of the first substrate, which is a semiconductor substrate having a structure that is not the separation region, and the second substrate. A bonded substrate is a main example. In addition, in the case of application to a method of manufacturing a semiconductor substrate, the members that can be separated are not the first substrate and the second substrate before joining.

In the present invention, the separation region is located at a position different from a bonding interface (joining surface) between the first substrate and the second substrate. In the separation step, it is necessary not to separate from the bonding interface but to separate in a separation region located at a position different from the bonding interface.

Therefore, the mechanical strength of the separation region is weaker than the mechanical strength of the bonding interface, and the separation region is broken before the bonding interface in the separation step. As a result, when the separation layer is broken, a portion of a specific thickness on the surface side of the first substrate is separated from the first substrate while being adhered to the second substrate, and is transferred onto the second substrate. Can be The separation region may be a porous layer formed by an anodization method or a layer from which microcavities formed by ion implantation can be obtained. Each of these layers contains many microvoids. Further, a heteroepitaxial layer in which strains and defects are concentrated in the crystal lattice may be used.

The separation region may be composed of a plurality of layers having different structures. For example, if necessary, porosity (p
It is also possible to use a porous layer having a plurality of porous layers having different org.

For example, the layer transferred from the first base to the second base obtained by separating the composite member in which the first base and the second base are bonded via the insulating layer is: Used as a semiconductor layer (SOI layer) on an insulating layer for manufacturing a semiconductor device or the like.

The spraying of the fluid that can be used for the separation can be realized by a so-called water jet method in which a high-pressure water stream is jetted from a nozzle. Also, an organic solvent such as alcohol may be used without using water, an acid such as hydrofluoric acid, nitric acid, or an alkali such as potassium hydroxide, or a liquid having an action of selectively etching a separation region. There may be. In particular, a liquid containing no abrasive particles is preferably used. Further, a fluid composed of a gas such as air, nitrogen gas, carbon dioxide gas, and rare gas may be used as the fluid. A fluid having gas or plasma having an etching effect on the separation region may be used.

By employing the above-described separation method as a method for manufacturing a semiconductor substrate, 1) a first substrate in which a porous single-crystal semiconductor layer and a non-porous single-crystal semiconductor layer are sequentially laminated on a substrate; The process of preparing,
Bonding the first substrate and the second substrate such that a composite member having the non-porous single-crystal semiconductor layer positioned inside is obtained; and A step of separating the composite member in the porous single crystal semiconductor layer by spraying a fluid; and 2) a predetermined depth of the first base made of the single crystal semiconductor. By implanting ions into the micro bubble layer (microc)
forming an ion-implanted layer from which the first substrate and the second substrate can be obtained via an insulating layer, and the surface of the first substrate into which the ions are implanted is located inside. Bonding the composite member to obtain a composite member, and spraying a fluid near the ion-implanted layer of the composite member, thereby separating the composite member at the ion-implanted layer. A manufacturing method and the like can be realized, and a semiconductor substrate that can solve the conventional problems can be manufactured.

[0031]

FIG. 1 is a schematic view for explaining a method of separating a composite member according to the present invention.

FIG. 1A shows a state before joining a first member 1 and a second member 2 in a disk shape (plate shape). First
The member 1 has a separation region 3 serving as a separation portion inside. The layer-shaped separation region 3 has lower mechanical strength than the layer region 5 on the bonding surface 4a side.

As shown in FIG. 1B, the two members 1 and 2 are joined with their joining surfaces 4a and 4b facing each other to form a disc-shaped composite member having a joining interface 14. A fluid 7 is ejected from a nozzle 8 toward an end of the separation region 3 on a side surface (end surface) 6 of the composite member, and is sprayed. The separation region 3 to which the fluid 7 has been sprayed is removed or collapsed. In this way, the composite member is separated into two members 11 and 12 at the separation region 3 as shown in FIG.

The layer region 5 does not already exist on the separation surface 13a of the one member 11 thus separated, and the layer region 5 is removed from the second member 2 so that the separation surface 13b is exposed.
Is transferred onto the joining surface 4b.

Thus, a member having the thin layer region 5 on the second member 2 is obtained.

If the second member 2 and the layer region 5 are made of different materials, members having different kinds of junctions can be easily manufactured. Specific examples of such materials include conductors, semiconductors,
It is an insulator, and two of them are selected to form the second member 2 and the layer region 5.

The separation region may be divided into two parts by the injected fluid at the boundary of the separation region, and may be formed as a fragile region so as not to damage regions other than the separation region. Specifically, if a plurality of minute gaps are included in the separation region, the separation region becomes fragile. Alternatively, strain may be created by implanting different ions. The minute voids are formed by pores of a porous body and bubbles by ion implantation as described later. The separation region is preferably set to about 0.1 μm to 900 μm. More preferably, it is 0.1 μm to 10 μm.

In the present invention, the flow of the fluid used for performing the separation can be realized by ejecting a pressurized fluid from a nozzle. "Water jet" is a method to make the jet flow faster and narrower with high pressure
A water jet method using water as a fluid as introduced in Vol. 1, No. 1, page 4 or the like can be used. The water jet that can be used in the present invention jets high-pressure water of several thousand kgf / cm ² pressurized by a high-pressure pump from a thin nozzle, whereby ceramics, metal, concrete, resin, rubber,
Cutting such as wood (However, when a hard material is SiO ₂ in water
Abrasives such as fine particles are added), processing, removal of the surface coating film, cleaning of the member surface, and the like can be performed. In the conventional use of the water jet, the main effect was to remove a part of the material as described above. That is, the water jet cutting is to remove the margin of the main member, and the removal of the coating film and the cleaning of the member surface are to remove unnecessary portions. When a water jet is used as the method of forming a fluid flow according to the present invention, at least a part of the separation region is removed from the side surface by jetting the water jet in accordance with a bonding edge of a side surface (end surface) of the bonded substrate. It is possible to do. In this case, first, a water jet is directly jetted onto the separation region exposed on the side surface of the bonded substrate and a part of the first substrate and the second substrate around the separation region. Then, the respective substrates are not damaged and only the separation region where the mechanical strength is weak is removed or collapsed by the water jet and separated into two substrates. Also, for some reason, even if the separation region is not previously exposed to the side surface and the portion is covered with a thin layer, the layer on the side surface covering the separation region is first removed with a water jet, and the process is continued as it is. What is necessary is just to remove the isolation region exposed from the side surface.

Although this is an effect that has been rarely used in the past, water is jetted into a narrow recess on the side surface around the bonded substrate where the two chamfered substrates are bonded, so that water is formed in the minute voids. It is also possible to separate the bonded substrates by intruding and breaking down the minute voids in the separation region where the structure is fragile and has a weak structure. In this case, cutting or removal is not the purpose, so there is almost no cutting debris in the separation area, and even if the material itself in the separation area cannot be removed by the water jet itself, it can be separated without using abrasive particles. Separation can be performed without damaging the obtained surface (separation surface). Thus, this effect can be considered as a kind of wedge effect by the fluid, not the effect of cutting or polishing. Therefore, this effect can be greatly expected when a concave or narrow gap is present on the side surface of the bonded substrate and a water jet is applied to apply a force in the direction of peeling off the separation region. If this effect is to be sufficiently exerted, it is preferable that the shape of the side surface of the bonded substrate is not convex but concave.

FIG. 2 is a diagram showing this effect. In FIG. 2, reference numerals 901 and 911 denote a first base, reference numerals 902 and 912 denote a second base, reference numerals 903 and 913 denote separation regions, and reference numerals 904 and 91.
4 is a semiconductor layer, 905 and 915 are insulating layers, 906 and 91
6 is a bonding interface, 907 is a fluid jet, 90
8, 918 indicate the direction of the force that the substrate receives from the fluid.

FIG. 2A conceptually shows the direction of the force applied by the water jet to the base when the end side surface of the bonded base is concave. A force is applied in a direction in which the concave portion is pushed and expanded, and thus in a direction in which the bonded substrates are peeled off from each other. On the other hand, FIG. 2B conceptually shows the direction of the force applied by the water jet to the base when the end side surface is convex. In this case, the direction in which the bases are peeled off from each other is shown. Since no force is applied, the substrate is difficult to separate unless at least an initial portion of the separation region is removed, but separation is possible if a fluid can enter the voids (pores) of the porous layer.

Even if the separation region is not previously exposed for some reason and the portion is covered with a thin layer, the same applies if the side surface of the bonded substrate is concave as described above. Since a force is applied in a direction that can expand and spread the vicinity of the separation region, the pressure first destroys the thin layer covering the separation region on the side surface, and then the separation region is expanded and destroyed, so that the separation effect is sufficiently exhibited. Is done. In order to receive the flow of the water jet without waste, it is desirable that the opening width of the concave portion is approximately equal to or larger than the diameter of the water jet. When the present invention is used for manufacturing a semiconductor substrate, the thickness of the bonded substrate, that is, the thickness of the composite member, that is, the thickness of each of the first substrate and the second substrate is less than 1.0 mm, It is less than 2.0 mm. Since the width of the opening of the concave portion is generally about 1/2 of this, the diameter of the water jet is 1.0 m.
m or less is preferable. Actually, a water jet diameter of about 0.1 mm is within the range of practical use.

The shape of the nozzle for ejecting the fluid can be any shape other than a circle. Nozzles on elongated slits can also be used. If a fluid is blown out from such a nozzle, a thin strip-shaped flow can be formed.

Various jetting conditions of the water jet can be freely selected depending on the kind of the separation region, the shape of the side surface of the bonded substrate, and the like. For example, jet pressure, jet scanning speed, nozzle diameter (ノ ズ ル water jet diameter), nozzle shape, distance between the nozzle and the separation area, fluid flow rate, and the like are important parameters.

In the actual separation step, the nozzle is scanned along the bonding surface while spraying a water jet from a direction parallel to the bonding surface, or the water jet is fixed and the bonded substrate is set in parallel. It can be separated by moving. In addition, the method of scanning the water jet in a fan shape around the nozzle,
As is often the case, if the bonded substrate is a disc-shaped disk such as an orientation rat or a notched wafer, a method in which the nozzle is fixed and the bonded substrate is rotated about its center as a rotation center can be adopted. Further, if necessary, the jet can be directed to the separation region from an angled direction instead of placing the nozzle in the same plane as the bonding interface. The water jet can be scanned in any manner as required, and is not limited to these methods. Since the diameter of the water jet is very small and the jetting direction is almost parallel to the substrate surface, a high pressure of several thousand kgf / cm ² is hardly applied to the substrate by vector decomposition. The force applied by the water jet to the bonded substrate other than the separation area is several tens
Since the weight is about 0 g, the substrate is not broken. For example, the pressure of such a water jet is a pressure at which the water jet cannot be cut even if the water jet is applied vertically to the surface of the wafer to cut the wafer.

As a fluid to be used, an organic solvent such as alcohol, an acid such as hydrofluoric acid or nitric acid, an alkali such as potassium hydroxide or other liquid having an action of selectively etching a separation region is used without using water. It is possible. Further, a gas such as air, nitrogen gas, carbon dioxide gas, and rare gas may be used as the fluid. A gas or plasma having an etching effect on the separation region may be used. It is desirable to use high-purity water, such as pure water or ultrapure water, from which impurity metals and particles are removed as much as possible for the method of separating composite members introduced into the semiconductor substrate manufacturing process. Since it is a completely low-temperature process, it can be sufficiently removed by washing after separation by a water jet. In particular, in the present invention, the fluid is preferably free of abrasive particles so that undesired scratches are not left on the substrate.

The semiconductor substrate according to the present invention can be used not only for manufacturing a semiconductor device, but also for using a single crystal semiconductor layer on an insulating layer to form a fine structure instead of an electronic device.

FIG. 3 is a schematic diagram showing a separation device according to one embodiment of the present invention.

Reference numeral 101 denotes a bonded wafer as a composite member, reference numeral 102 denotes a fluid ejection nozzle, reference numeral 103 denotes a vertical movement mechanism for adjusting the vertical position of the nozzle 102, reference numeral 104 denotes a nozzle 10
Reference numeral 115 denotes a horizontal moving mechanism for adjusting the horizontal position of the wafer, and reference numeral 105 denotes a wafer holder as a holder. 113, 114 and 116 are guides, respectively. In the apparatus shown in FIG.
03, 104, and 115, the nozzle 102 and the wafer 1
01 is positioned with respect to the end of the separation region, and a high-pressure fluid is ejected from the nozzle 102 toward the end of the separation region on the side surface of the wafer 101, and the horizontal movement of the nozzle and By moving up and down,
The wafer separation operation proceeds.

Reference numeral 106 denotes a backing material made of a porous or non-porous elastic material used as needed.

FIG. 4 is a schematic perspective view showing another example of the separation device used in the present invention. In FIG. 4, 401 is
A semiconductor wafer as a composite member obtained by laminating and integrating two Si wafers, in which a porous layer serving as a separation region exists. Numerals 403 and 404 denote holders for adsorbing / fixing the semiconductor wafer 401 by means of a vacuum chuck, which are located on the same rotation axis and are rotatably mounted. Further, the holding body 404 is fitted to a bearing 408 and is supported by a support base 409, and is directly connected to a rotating shaft of a speed control motor 410 at a rear end. As a result, the motor 4
Holder 40 at any speed by controlling 10
4 can be rotated. Also, another holding body 4
03 is fitted to the bearing 411 and is supported by the support 409, and a force is applied in a direction in which the holding body 403 is separated from the semiconductor wafer 401 by interposing a compression spring 412 between the support 409 and the support 409 at the rear end.

First, the semiconductor wafer 401 is set so as to be aligned with the concave portion of the positioning pin 413,
Hold. The holder 404 arranges the upper and lower positions of the semiconductor wafer 401 with the pins 413 so that the semiconductor wafer 40
One central part can be held. The holder 403 is moved leftward against the spring 412 to a position where the holder 403 sucks / holds the semiconductor wafer 401. At this time, a force is applied to the holding body 403 in the right direction by the compression spring 412. At this time, the compression spring 412 adjusts the returning force of the compression spring and the force of the holding body 403 to attract the semiconductor wafer 401 so that the holding body 403 does not separate from the semiconductor wafer 401, and balances the two.

The fluid is sent from the jet pump 414 to the jet nozzle 402 and is continuously discharged for a certain period of time until the ejected fluid is stabilized. When the flow of the fluid is stabilized, the nozzle is moved, the shutter 406 is opened, and the fluid ejected from the jet nozzle 402 to the center of the thickness of the semiconductor wafer 401 is applied to the side surface of the base 101. At this time, the semiconductor wafer 401 and the holder 403 are rotated by rotating the holder 404 by the motor 410. The fluid is applied near the center in the thickness direction of the semiconductor wafer 401,
The semiconductor wafer 401 is spread in two and the semiconductor wafer 40 is spread.
Within one, the relatively weak porous layer is destroyed and eventually separates into two.

At this time, as described above, the semiconductor wafer 40
1 is uniformly applied to the fluid, and the holding body 403 exerts a force in the right direction while holding the semiconductor wafer 401, so that the separated semiconductor wafers 401 are hard to slide after being separated. .

It is possible to separate the bonded wafer 401 by rotating the nozzle 402 in a direction parallel to the bonding interface (surface) of the bonded wafer 401 without rotating the bonded wafer 401. When the nozzle 402 is separated by scanning the nozzle 402 without rotating the aligned wafer 401, a nozzle diameter of 0.15 mm has a diameter of 20 mm.
Although high-pressure water of 0 kgf / cm ² is required, when the bonded wafer 401 is rotated and the nozzle 402 is fixed and separated, separation can be performed at a pressure of 200 kgf / cm ² .

This is because water can be made to act as a force to push and spread the water pressure more efficiently than in a method in which the nozzle is scanned by ejecting water toward the center of the bonded wafer 401.

The following effects can be obtained by reducing the water pressure.

1) The wafer can be separated without cracking. 2) A lot of jets can be used at the same time because the pump capacity is sufficient. 3) The pump can be made small and light. 4) The range of material selection for the pump and piping system. 5) The pump and, in particular, the jet noise of the jet are reduced, making it easier to take soundproofing measures.

The wafer holding means shown in FIG.
The holders 403 and 404 are held by pulling from both sides by pressing the holders 403 and 404 from both sides. In such a case as well, the high-pressure water spreads and spreads the bonded wafer 401 and proceeds while making a small gap, and can be finally separated into two bodies.

The shapes of the holders 403 and 404 are such that the smaller the contact portion with the bonded wafer 401 is, the more the high pressure water spreads the bonded wafer 401 and the more the bonded wafer 4
01 can move flexibly. In this way, stress concentration due to excessively high pressure and water at the separation interface of the bonded wafer 401 can be prevented from cracking and spread easily. The above enables effective separation. For example, the holders 403, 4
04, the diameter of the contact portion with the bonded wafer 401 is 30 m.
m, the nozzle diameter is 0.2 mm and the pressure is 400
At kgf / cm ² , the bonded wafer 401 can be separated during one rotation of the bonded wafer 401 without cracking.

Further, the larger the contact portion of the holding members 403 and 404 with the bonded wafer 401 is, the more the high pressure water spreads the bonded wafer 401, so that the back surface of the bonded wafer 401 is supported, so that cracks during separation can be prevented. . When the diameter of the contact portion between the holding members 403 and 404 and the bonded wafer 401 is set to 100 mm or more, the nozzle diameter is 0.2 m
m, pressure 400 kgf / cm ² bonded wafer 40
1 can be separated without cracking.

When foreign matter such as particles is inserted into the contact portion between the holders 403 and 404 and the bonded wafer 401, the bonded wafer 401 is not held vertically, and the nozzle 402 is moved from the uppermost vertical direction of the bonded wafer 401. In some cases, the high-pressure fluid does not effectively hit the separation interface of the bonded wafer 401 in some cases. The holders 403, 4
By forming the contact surface of the bonded wafer 401 of FIG. 4 with a large number of minute projections, the contact area can be reduced as much as possible, thereby reducing the effect of pinching foreign matter.

In the support shown in FIG. 4, since the holder 404 rotates and the holder 403 rotates together therewith, a slight force is applied in the direction in which the rotation is stopped, so that the wafer 401 bonded immediately before the entire surface is separated is separated. Surfaces may be separated by twisting. In that case, the holder 403
Is rotated in synchronism with the holding member 404, so that the separation surface can be prevented from being twisted. The detailed method will be described later.

FIG. 5 shows another separation device of the present invention.

In FIG. 5, reference numeral 204 denotes a wafer horizontal drive mechanism, 205 denotes a wafer carrier, and 206 denotes a wafer transfer arm. As shown in FIG. 5, the wafer cassette 205 is placed on the cassette table 207 so that the wafer 201 is horizontal. The wafer 201 is the wafer transfer robot 20
6, the wafer is transferred to the wafer support 204. Wafer 20
1 is placed on a wafer support 204 by a support moving mechanism such as a belt conveyor.
It is sent to the position of 3. A high-pressure fluid is applied to the recess formed by the beveling of the two wafers from the nozzles 202 and 203 of the fluid jet device arranged on the side of the wafer, and the separation area is separated from a direction parallel to the bonding interface (surface) of the wafer. Inject toward. At that time, the nozzle was fixed, and the bonded wafer was scanned in the horizontal direction so that the high-pressure fluid was along the recess formed by beveling. The nozzles may be only on one side 202 or 203, and if necessary, both nozzles 202 and 203 may be used.

Thus, the wafer can be divided into two parts via the porous Si layer. Although not shown here, the separated wafer is separated and stored on the first substrate side and the second substrate side by another transfer robot.

In the horizontal jet method, it is not necessary to fix the wafer, and there is little risk that the wafer after the two divisions will fly out of the wafer support 204 by its own weight. Alternatively, after the wafer is transferred to the wafer support, the pins for preventing the protrusion from protruding above the wafer may be projected from the wafer support 204, or the upper portion of the wafer may be lightly pressed.

Further, a plurality of bonded wafers are set side by side on the surface in the vertical direction, and one set of the bonded wafers is horizontally scanned and separated. It is also possible to move and separate the second set of bonded wafers sequentially by horizontal scanning as in the first set.

FIG. 6 schematically shows another separation apparatus of the present invention.

FIG. 6 conceptually shows the nozzle of the water jet device used and its movement. As shown in FIG. 6, the bonded wafer 301 is held by the holding body 310 and stands upright. A high-pressure fluid is jetted from a nozzle 302 of a jet device disposed above the concave portion formed by beveling of both wafers from a direction parallel to the bonding interface (surface) of the bonded wafers.
At this time, the nozzle 30 is positioned in the same plane as the wafer bonding surface.
2 and a fulcrum 30 for swiveling the nozzle in a fan shape in a plane
Put 3. The jet flow is also swung in this plane while the nozzle is swung in the wafer bonding plane. This makes it possible to move the high-pressure jet while ejecting it along the concave portion or gap of the bonded portion at the edge of the bonded wafer. In this way, a wide range can be used without using a robot for accurately moving the nozzle within the bonding surface or using a mechanically more complicated mechanism such as moving or rotating the bonded wafer. The fluid can be ejected to the separation region of.

FIG. 7 conceptually shows another separation apparatus of the present invention, that is, another method of jetting a jet 503 around the bonded wafer 501. By fixing the bonded wafer 501 by the holding body 510 and rotating the nozzle 502 around the bonded wafer 501, the jet 503 can be jetted to the bonded portion on the entire periphery of the wafer edge portion. Holding the center portion of the wafer, a rail (not shown) concentric with the wafer is set around the wafer 501, and a jig 512 fixing the nozzle 502 is slid on the rail to bond the wafer 501 from the periphery. Jet 503 can be ejected to the portion.

FIG. 8 shows another example of the separation apparatus of the present invention.

In FIG. 8, 601 is the first wafer, 602 is the second wafer, 603 is the bonding surface, 6
04 indicates a fluid jet, 605 indicates the direction of the force applied to the wafer from the fluid jet, and 606 indicates the angle formed by the fluid jet with respect to the bonding surface. In this example, the nozzle 611 and the holder 6 are arranged such that the jet direction of the jet from the nozzle 611 forms an inclination angle α with respect to a direction parallel to the separation surface of the wafer.
Ten positions are defined.

The wafer can be held by an apparatus as shown in FIG. 4 and its nozzles can be arranged as shown in FIG. Since the jet 604 has an angle α (606) with respect to the bonding surface 603, the pressures applied to the two wafers 601 and 602 are not equal. In the example of FIG. 8, of the wafers 601 and 602, the side 602 on the side where the jet is inclined receives a relatively small force, and the wafer 601 on the opposite side receives a larger force. Porous S
When the jet is tilted to the opposite side of the wafer on which the i is formed, the layer having porous Si or microbubbles is easily broken.
It is desirable to set the bonded wafer so that the wafer 601 has porous Si.

FIG. 9 shows another separation device of the present invention.

In FIG. 9, reference numerals 705 and 706 denote a vertical drive mechanism for the fluid jet apparatus nozzles 702 and 703,
Denotes a horizontal drive mechanism for the water jet device nozzle 704, and 708 denotes a wafer holder.

As shown in FIG. 9, the bonded wafer 701 is held upright by the wafer holder 708 from both sides of the wafer. Here, the side with the orientation flat is facing upward. A high-pressure fluid is bonded to a recess or gap formed by beveling of both wafers 701 from a plurality (three in this example) of water jet device nozzles 702, 703, and 704 disposed above or beside the recess. Injection was performed from a direction parallel to the bonding interface (surface) of the wafer. Fig. 3 shows the structure of a single nozzle.
Is the same as At that time, the plurality of nozzles 702, 703,
704 was scanned according to guides 711, 712, and 713 in a direction in which high-pressure pure water moves along a gap formed by beveling.

Thus, the wafer is divided into two parts.

In the case of one nozzle, a high pressure was required to separate a distance corresponding to the diameter of the wafer. Alternatively, in the case of a pressure that can be separated only by the distance of the radius of the wafer, it is necessary to turn the wafer upside down and further separate the distance of the radius from the opposite side. By using a plurality of nozzles, it is sufficient for each nozzle to separate the radius of the wafer, and the entire wafer can be separated at once without having to turn over the wafer and spray high-pressure water again.

FIG. 10 shows another separation device of the present invention. In FIG. 10, reference numeral 801 denotes a bonded wafer as a composite member; 802, a nozzle of a fluid jet;
Indicates a fluid. As shown in FIG. 10, the bonded wafers are held upright on a holder 811, and a slit-like slit of a jet device disposed above or beside the gap formed by beveling the two wafers. High-pressure pure water is sprayed from a nozzle having an opening in a direction parallel to the bonding interface (surface) of the bonded wafer. The slit is arranged in parallel with the bonding interface (surface) of the bonded wafers, and is positioned so that a linear water flow is properly jetted into a gap formed by beveling of both wafers. The plurality of nozzles are scanned in a direction in which the high-pressure fluid moves along a gap formed by beveling.

If the length of the slit is set to be longer than the diameter of the wafer, the scanning of the nozzle becomes unnecessary.

The effect of this slit-shaped nozzle is that the wafer can be divided at a lower pressure than a single micro-diameter nozzle. Even at a low pressure, by increasing the area from which the high-pressure water flows, the energy used for dividing the wafer can be increased, and the wafer can be more easily peeled off.

The nozzles that can be used in the present invention are not limited to those having slit-shaped openings, and the same applies when a plurality of nozzles 1202 are closely arranged in a straight line as shown in FIG. The result is obtained. Here, reference numeral 1211 denotes a wafer holder.

FIG. 12 shows another separation apparatus according to the present invention, in which a plurality of wafers can be simultaneously separated using a plurality of jets.

The basic configuration of the apparatus shown in FIG. 12 is the same as that shown in FIG. The wafer 1001a is set on the holder 1005a. The high-pressure fluid ejected from the nozzle 1002a
To the beveling section. The nozzle 1002a can be moved by the horizontal moving mechanism 1004a in a direction perpendicular to the paper surface while high-pressure water hits the beveling portion. The same operation is performed for the nozzle 1002b, the horizontal movement mechanism 1004b,
This is also possible with the device on the right side of the figure having the holder 1005b, thereby doubling the throughput. Although two sets are shown in this figure, more than two sets may be installed.

If the capacity of the high-pressure pump is not large, the right wafer may be replaced while the high-pressure water on the left is being sprayed, and this may be alternately performed. As a result, only one set of loader and unloader robots is required.

FIG. 13 shows another separating apparatus according to the present invention, in which wafers 1101a, b, c, d, and e are set on the wafer holding means 1105 at one time. A plurality of nozzles 1102a to 1102 are attached to one set of nozzle moving mechanisms 1103 and 1104.
2e is installed. The nozzle interval is the same as the wafer fixing interval. The holding mechanism and the nozzle moving method are the same as those in FIG.

The five wafers are held on holders 1115 a, 1115 b, and 1115 which can move horizontally on guide 1114.
c, 1115d, 1115e, and 1115f are fixed with their central axes aligned.

The five nozzles 1102a to 1102e are connected via a separator 1113 to a common supply pipe for fluid and a movable supply pipe 1112 which also serves as a mechanism for moving the nozzle up and down.

After stabilizing the ejection amount and pressure of the fluid from each nozzle at the standby position, all the nozzles 1102a to 1102e move to the wafer separation position along the guide 1111 and separate the guide 111 while separating the wafer. Follow along. When the separation is completed, the injection amount of the fluid is reduced or stopped and the nozzle is returned to the standby position.

In the apparatus shown in FIGS. 10 to 13, the separation can be performed by rotating the wafer holder and ejecting a fluid while rotating the wafer.

FIGS. 14 and 15 are a top view and a side view showing a composite material separating apparatus used in the present invention.

This separating device has a rotation synchronizing mechanism, and has a first holder for holding the first surface of the composite member,
The second holding member holding the second surface of the composite member can be rotated in the same direction at the same angular velocity.

When a rotational driving force is applied to only one surface of the composite member, or when the above-described synchronization is not established, the following phenomenon is likely to occur.

Immediately before the wafer, which is a composite member, is completely separated over the entire surface, there is always a moment at which a minute region to be finally separated remains somewhere on the separation surface without being separated. The following two separation modes can be considered depending on the position of the final remaining minute area.

One is the case where the final remaining area remains almost at the center of the separation plane, and the second is the case where the final remaining area remains in the area other than the center.

FIG. 16 conceptually shows this situation.

When the former occurs, it may be in the case of a separation state in which separation is performed uniformly from the periphery toward the center, or when the strength near the center of the separation surface is high. In this case, if a rotational driving force is applied only to the holder 21 on one side of the wafer,
This rotation causes the final remaining microregion to be separated by being screwed off.

When the latter separation mode occurs, in the initial stage of the fluid spraying, when the separation state is such that the cracks enter from a certain peripheral portion over the radius of the wafer and separate at a time, or when the separation surface is formed. This is the case where the strength other than near the center is high. In this case, when a rotational driving force is applied only to the holder 21 on one side of the wafer, the final remaining minute area is separated by the shear stress due to the rotation.

Since the independent holding force is not applied to the opposite holding member 22 and the holding member 22 is merely rotated through the wafer, the opposite holding member 22 can be held lightly by a bearing or the like. This is because, even if it is, the force is slightly applied in the direction in which the holding body 22 stops rotating.

Due to the twisting and shearing, a complicated force acts on the separation surface in a direction other than the vertical direction, and undesired separation may occur on a surface other than the separation surface.

Therefore, when the wafer is separated while rotating, if both sides of the wafer are driven to rotate without synchronization, the wafer may be separated from a surface other than the desired separation surface at the time of separation, or the wafer or the active layer may be separated. Damage can occur. These phenomena cause a significant decrease in yield.

A motor support 36 for supporting the speed-controllable motor 32 is provided on the support 40,
A pair of shaft supports 37 and 38 for rotatably supporting the motor shaft 31 are fixed.

Further, a first holder support 33 for rotatably supporting the holder 21 and a second holder support 34 for rotatably supporting the holder 22 are provided on the support 40. , Has been fixed.

The timing pulley 29 attached to the motor shaft 31 and the timing pulley 25 attached to the rear end of the rotating shaft 23 of the holder 21 are connected by a timing belt 27 so as to rotate in the same direction.

Similarly, the timing pulley 30 attached to the motor shaft 31 and the timing pulley 26 attached to the rear end of the rotating shaft 24 of the holder 22 are connected by a timing belt 28 so as to rotate in the same direction. I have.

The pulleys 25 and 26 have the same driving radius, and the pulleys 29 and 30 have the same driving radius.

The same timing belts 27 and 28 are used.

Thus, the driving force of the motor 32 is
1 is transmitted to the holders 21 and 22 via the respective pulleys and belts, and rotates the holders 21 and 22 in the same direction and at the same angular speed at the same timing.

In FIG. 15, reference numeral 60 denotes a jet nozzle 61 for ejecting a fluid, and a shutter. The nozzles and shutters are simplified for clarity.

The nozzle 60 is fixed on the support base 40 by a fixing jig (not shown). A wafer positioning member 35 is provided on the support base 40 in accordance with the position of the nozzle 60.

FIG. 17 is a partial cross-sectional view of the holder of the separation device in a state before holding the wafer 20.

The holders 21 and 22 hold holding units 45 a and 46 a that perform actual operations of sucking and holding a wafer, and the holding units 4.
Fixed portions 45b, 46b for rotating 5a, 46a together with the rotating shafts 23, 24, and detents 41, 42, 43,
44 and the like.

The holding portion 45a can move in the direction away from the rotary shaft 23 (to the right in the figure) against the compression spring (coil spring) 47 by the pressurized gas sent to the tube 52 and the pressurizing path 56.

An opening op is provided near the center of the holding portion 45a, and communicates with the pressure reducing passage 55 in the rotating shaft. Opening o
p is evacuated to a pressure lower than the atmospheric pressure by a vacuum pump (not shown) connected via a decompression tube 51.

As shown in FIG. 17, the holding portions 45a for directly attracting the wafer are guided by the rotating shaft 23, and the holders 21 and 22 are moved rightward by the air pressure introduced from the pressure tube 52. Then, the compression spring 47 retreats leftward in the drawing. Further, the holding portion 45a is provided with
2 rotates together with the rotating shaft 23. The holding body 22 is basically mirror-symmetrical to the holding body 21 and has the same mechanism. However, when the bonded wafer 20 is positioned and held on the holding body 22, the positions of the bonded wafer 20 and the nozzle 60 are always fixed. The pressing force is controlled or adjusted so that the holding body 21 always exerts a stronger force than the holding body 22 in the forward movement and the holding body 22 exerts a stronger force than the holding body 21 in the backward movement so as to be positioned. Have been.

The method of using this apparatus, that is, the method of separating the composite member of the present invention is as follows.

First, as shown in FIG. 17, the bonded wafers 20 are set so as to follow the notches of the positioning table 35. Next, as shown in FIG. 18, the holding portion 45a is advanced by the introduction of pressurized air, and the holding body 21 sucks / holds the wafer.
The holder 21 holds the bonded wafer 20 on the positioning table 3.
The central part of the bonded wafers 20 can be held by following the notches of No. 5. Bonded wafer 2
0 is held at the correct position, the nozzle 60 is positioned in the vertical direction at the top of the bonded wafer 20, and the distance between the bonded wafer 20 and the nozzle 60 is 10 to 30 mm.
It is configured to be. Next, the holding unit 4 of the holding body 22
6a is advanced to the left in the drawing to be adsorbed / held on the bonded wafer 20, and then the introduction of the pressurized air into the holding portion 46a is stopped. The bonded wafer 20 stops in a state where a force is applied in the right direction in the figure by the force generated by the compression spring and the vacuum suction force. At this time, the force generated by the compression spring is
Since a does not exceed the force for adhering the bonded wafers 20, the insides of the decompression paths 55 and 57 are broken by vacuum, and the adsorbing force is lost and the wafer 20 does not fall.

Next, a fluid containing no abrasive particles is fed from the pump 62 to the nozzle 60, and is continuously discharged for a certain period of time until the jetted water is stabilized. When the water is stable, shutter 61
Is opened, and high-pressure water spouted from the nozzle 60 is applied to the center of the bonded wafers 20 in the thickness direction. At this time, by rotating the speed control motor 32, the holders 21 and 22 are synchronously rotated to rotate the wafer 20. When the high-pressure fluid strikes the center of the wafer 20 in the thickness direction, the high-pressure fluid also enters the separation region, pushes the bonded wafer 20 apart into two members, and finally separates the bonded wafer 20 into two members.

At this time, as described above, high-pressure water is evenly applied to the bonded wafers 20 and the holders 21 and 22
Is applied in the direction of pulling the bonded wafers 20, so that the bonded wafers 20 are further separated from each other after separation, and the separated portions do not slide.

The wafer support means shown in FIGS. 17 to 20 support the holders 21 and 22 by applying a force in the direction of retreating from the wafer.
The wafer can be held by the pressing pressure by applying a force in the forward direction. Also in such a case, the high-pressure water pushes the bonded wafer 20 apart and infiltrates while making a slight gap, and finally separates the wafer into two pieces. In this method, when the holders 21 and 22 were not synchronized, the separated surfaces of the separated wafers were damaged by sliding, but when rotated in synchronization, there was no damage. Further, when a force is applied to the holding members 21 and 22 in the retreating direction, the holding members 21 and
Since the amount of displacement is different between a part that is not separated by pulling in the retreating direction and a part that is separated by 2, the balance of the bonded wafers 20 is lost, and high-pressure water is applied to the bonded wafers 20, causing cracks. However, when a force is applied to the holders 21 and 22 in the forward direction, the bonded wafers 20 can be separated stably without breaking the balance.

The completely separated bonded wafer is subjected to a force in the backward direction while applying a high-pressure or normal-pressure fluid to cut off the surface tension of the intervening water and completely separate into two. can do.

As described above, the separation device according to the present invention comprises:
One or more composite members are sequentially or simultaneously separated by a fluid. Regarding the manner of disposing the composite members, the composite members may be arranged in a direction normal to the surface, or may be arranged in a direction parallel to the surface.

Further, the composite member may be rotated or translated parallel to the surface so as to be applied to the fluid, or the flow of the fluid may be moved parallel to the surface and applied to the side surface of the composite member. Alternatively, both may be moved together.

[0125]

【Example】

(Example 1) (Single layer porous / nozzle scanning) Specific resistance 0.01 Ω · cm
The first P-type (or N-type) single crystal Si substrate was anodized in an HF solution. The anodizing conditions were as follows.

Current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1:
1 hour: 11 (min) Thickness of porous Si: 12 (μm)

The porous Si is used as a separation layer in order to form a high-quality epitaxial Si layer, and the functions are shared by one layer.

The thickness of the porous Si layer is not limited to this, but can be used from several hundred μm to about 0.1 μm.

This substrate was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm. The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, as an insulating layer, a 200 nm oxide film (Si) was formed on the surface of the epitaxial Si layer by thermal oxidation.
O ₂ layer).

A second S prepared separately from the surface of the SiO ₂ layer
After overlapping and contacting the surface of the i-substrate, 1180
Heat treatment was performed at a temperature of 5 ° C. for 5 minutes, and bonding was performed.

In order to separate the bonded substrates formed as described above using the apparatus shown in FIG. 3, the bonded wafers are supported upright on both sides of the wafer by a wafer holder. An abrasive-free water jet disposed above the gap formed by beveling the two wafers was 2,000 kN from a 0.15 mm nozzle.
High-pressure pure water was sprayed at a pressure of gf / cm ² from a direction parallel to the bonding interface (surface) of the bonded wafer.
Then, the nozzle was scanned by a nozzle horizontal drive mechanism in a direction in which high-pressure pure water moved along a gap formed by beveling. At this time, if the elastic body 106 (for example, viton, fluorine-based rubber, silicone rubber, or the like) is used in a portion where the wafer and the holding member are in contact with each other, the wafer is vertically opened in the plane, so that the wafer is held by the wafer holding tool. However, the high-pressure water also penetrated into the porous Si layer, and the wafer could be separated.

As a result, the SiO ₂ layer, the epitaxial Si layer, and the porous S
Part of the i-layer was transferred to the second substrate side. Only porous Si remained on the surface of the first substrate.

After that, the porous Si layer transferred onto the second substrate is selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The single-crystal Si remained without being etched, and the porous Si was selectively etched and completely removed using the single-crystal Si as a material for an etch stop.

The etching rate of the non-porous Si single crystal with respect to the etching solution is extremely low, the selectivity with respect to the etching rate of the porous layer reaches more than the tenth power, and the etching amount (number) About 10 angstroms)
Is a practically negligible decrease in film thickness.

That is, a single-crystal Si layer having a thickness of 0.2 μm was formed on the Si oxide film. There was no change in the single crystal Si layer even by selective etching of the porous Si. When the thickness of the formed single crystal Si layer was measured at 100 points over the entire surface in the plane, the uniformity of the film thickness was 201.
nm ± 4 nm.

As a result of observation of a cross section by a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
Mean square roughness in the area of 50 μm square is about 0.2 nm
Was equivalent to a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result can be obtained by forming it on the surface of the second substrate or both.

Further, the porous Si remaining on the first substrate was also selectively etched while being stirred with a mixed solution of 40% hydrofluoric acid and 30% hydrogen peroxide. After that, a surface treatment such as hydrogen annealing or surface polishing is performed and the first
The above-described steps could be repeated by using this as a substrate or as a second substrate.

(Example 2) (Two layers of porosity / nozzle scanning) Specific resistance 0.01 Ω · cm
Was subjected to two-stage anodization in an HF solution to form two porous layers.
The anodizing conditions were as follows.

First stage current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1:
1 time: 5 (min) Thickness of first porous Si: 4.5 (μm) Second stage current density: 30 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1: 1
1 time: 10 (seconds) Thickness of the second porous Si: 0.2 (μm)

By forming the porous Si layer into a two-layer structure, the porous Si of the surface layer previously anodized at a low current is used to form a high quality epitaxial Si layer, and then the anode is formed at a high current at the anode. The lower porous Si thus formed was used as a separation layer to separate functions. Therefore,
The thickness of the low-current porous Si layer is not limited to this,
It can be used up to several hundred micrometers.

The third and subsequent layers may be formed after the formation of the second porous Si layer.

This substrate was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm. The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ Gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, as an insulating layer, a 200 nm oxide film (Si) was formed on the surface of the epitaxial Si layer by thermal oxidation.
O ₂ layer) was formed.

A second S prepared separately from the surface of the SiO ₂ layer
After overlapping and contacting the surface of the i-substrate, 1180
Heat treatment was performed at a temperature of 5 ° C. for 5 minutes, and bonding was performed.

The bonded substrate formed as described above was separated using the apparatus shown in FIG. The separation process was the same as in Example 1. As a result, a part of the SiO ₂ layer, the epitaxial Si layer, and the porous Si layer originally formed on the surface of the first substrate were transferred to the second substrate side.
Only porous Si remained on the surface of the first substrate.

Thereafter, the porous Si layer transferred onto the second substrate was selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The single-crystal Si remained without being etched, and the porous Si was selectively etched and completely removed using the single-crystal Si as a material for an etch stop.

That is, a single-crystal Si layer having a thickness of 0.2 μm was formed on the Si oxide film. There was no change in the single crystal Si layer even by selective etching of the porous Si. When the film thickness of the formed single crystal Si layer was measured at 100 points over the entire surface, the uniformity of the film thickness was 200.
nm ± 4 nm.

As a result of observation of a cross section by a transmission electron microscope, S
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
Mean square roughness in the area of 50 μm square is about 0.2 nm
Was equivalent to a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result can be obtained by forming it on the surface of the second substrate or both.

Further, the porous Si remaining on the first substrate was also selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. After that, a surface treatment such as hydrogen annealing or surface polishing is performed and the first
The above-described steps could be repeated by using this as a substrate or as a second substrate.

Example 3 (Separation Layer / Nozzle Scan by Porous Si + Ion Implantation) A P-type first single-crystal Si substrate having a specific resistance of 0.01 Ω · cm was anodized in an HF solution. .

The anodizing conditions were as follows.

Current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1:
1 hour: 11 (min) Thickness of porous Si: 12 (μm)

This substrate was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm. The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, as an insulating layer, a 200 nm oxide film (Si) was formed on the surface of the epitaxial Si layer by thermal oxidation.
O ₂ layer).

Here, ions were implanted from the surface of the first substrate so that the projection range was at the interface between the epitaxial layer / porous Si or the interface between the porous Si / substrate or the porous Si layer. As a result, a layer serving as a separation layer was formed as a microbubble layer or a strained layer formed of a layer with a high concentration of implanted ion species at a depth of the projection range.

Before the superposition, a pretreatment such as a plasma treatment of N ₂ is performed, and the surface of the SiO ₂ layer and the second
After overlapping and contacting the surface of the Si substrate of
Heat treatment was performed at a temperature of 00 ° C. for 10 hours, and bonding was performed.

The bonded substrate formed as described above was separated using the apparatus shown in FIG. The separation process was the same as in Example 1. As a result, a part of the SiO ₂ layer, the epitaxial Si layer, and the porous Si layer originally formed on the surface of the first substrate were transferred to the second substrate side. Only porous Si remained on the surface of the first substrate.

Thereafter, the porous Si layer transferred onto the second substrate was selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The single crystal Si remained without being etched, and the porous Si was selectively etched and completely removed using the single crystal as a material for the etch stop.

That is, a single-crystal Si layer having a thickness of 0.2 μm was formed on the Si oxide film. There was no change in the single crystal Si layer even by selective etching of the porous Si. When the film thickness of the formed single crystal Si layer was measured at 100 points over the entire in-plane surface, the uniformity of the film thickness was 201.
nm ± 4 nm.

As a result of observing the cross section with a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
The mean square roughness was about 0.2 nm in a 50 μm square area, which was equivalent to that of a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result can be obtained by forming it on the surface of the second substrate or both.

Further, the porous Si remaining on the first substrate was also selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. After that, a surface treatment such as hydrogen annealing or surface polishing is performed and the first
The above-mentioned process was able to be repeated by using as a second substrate or as a second substrate.

In this embodiment, the ion implantation is performed after the epitaxial Si layer is formed. However, the ion implantation may be performed in the porous Si layer or at the porous Si / Si substrate interface before the epitaxial growth.

Example 4 (Bubble Layer / Nozzle Scan by Ion Implantation) On the surface of the first single crystal Si substrate, an oxide film (SiO ₂ layer) of 200 mn was formed as an insulating layer by thermal oxidation.

Here, ions were implanted from the surface of the first substrate so that the projection range was in the Si substrate. As a result, a layer serving as a separation layer was formed as a microbubble layer or a strained layer formed of a layer with a high concentration of implanted ion species at a depth of the projection range.

Before the superposition, a pretreatment such as N ₂ plasma treatment is performed, and the surface of the SiO ₂ layer and the surface of the separately prepared second Si substrate are superposed and contacted.
Heat treatment was performed at a temperature of 10 ° C. for 10 hours, and bonding was performed.

The bonded substrate formed as described above was separated using the apparatus shown in FIG. The separation process was the same as in Example 1.

As a result, the SiO ₂ layer, the surface single crystal layer, and part of the separation layer originally formed on the surface of the first substrate were transferred to the second substrate. The remainder of the separation layer remained on the first substrate surface.

Thereafter, the separation layer transferred onto the second substrate was selectively etched while being stirred with a mixed solution of 49%, hydrofluoric acid and 30% hydrogen peroxide. The single-crystal Si remained without being etched, and the separation layer was selectively etched using the single-crystal Si as a material for an etching stop and completely removed.

If the remaining separation layer is sufficiently thin, this etching step may be omitted.

That is, a single-crystal Si layer having a thickness of 0.2 μm was formed on the Si oxide film. The selective etching of the separation layer did not change the single crystal Si layer at all. When the thickness of the formed single crystal Si layer was measured at 100 points over the entire in-plane surface, the uniformity of the film thickness was 201 nm.
± 4 nm.

As a result of observation of a cross section by a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
Mean square roughness in the area of 50 μm square is about 0.2 nm
Was equivalent to a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result can be obtained by forming it on the surface of the second substrate or both.

The separation layer remaining on the first substrate was also selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. After that, a surface treatment such as hydrogen annealing or surface polishing was performed and the substrate was used again as the first substrate or the second substrate, and the above-described steps could be repeated.

This embodiment is an example in which the surface region of the Si wafer is originally transferred to the second substrate via the separation layer formed by ion implantation. You may transfer to a 2nd board | substrate. In addition, after the surface SiO ₂ was removed after the ion implantation of this embodiment, an epitaxial layer was formed and the SiO _{2 was} further removed.
After the formation, the bonding step may be started, and the epitaxial layer may be transferred to the second substrate via the separation layer by ion implantation. In the latter case, the surface area of the Si wafer is also originally transferred.

Example 5 (Water Horizontal, Wafer Movement) A P-type first single-crystal Si substrate having a specific resistance of 0.01 Ω · cm was anodized in an HF solution.

The anodizing conditions were as follows.

Current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1:
1 hour: 11 (min) Thickness of porous Si: 12 (μm)

The porous Si is for forming a high-quality epitaxial Si layer and for use as a separation layer.

The thickness of the porous Si layer is not limited to this, but can be used from several hundred μm to about 0.1 μm.

This substrate was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm. The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, as an insulating layer, a 200 nm oxide film (Si) was formed on the surface of the epitaxial Si layer by thermal oxidation.
O ₂ layer).

The second S prepared separately from the surface of the SiO ₂ layer
After overlapping and contacting the surface of the i-substrate, 1180
Heat treatment was performed at a temperature of 5 ° C. for 5 minutes, and bonding was performed.

The bonded substrate formed as described above was separated using the apparatus shown in FIG. As shown in FIG. 5, the wafer cassette 205 was placed on the cassette table 207 so that the wafer 201 was horizontal.

The gap formed by the beveling of the two wafers is 2,000 kg from the 0.15 mm nozzles 202 and 203 of the water jet device arranged on the side.
High-pressure pure water at a pressure of f / cm ² was sprayed from a direction parallel to the bonding interface (surface) of the bonded wafer. Then, the nozzle was fixed, and the bonded wafer was scanned in the horizontal direction so that high-pressure pure water was along the gap formed by beveling.

As a result, the wafer was divided into two parts via the porous Si layer. Next, the illustrated and separated wafers were separated and stored on the first substrate side and the second substrate side by another transfer robot, and were collected.

The SiO ₂ formed on the surface of the first substrate
A part of the layer, the epitaxial Si layer, and the porous Si layer were transferred to the second substrate side. Only porous Si remained on the surface of the first substrate.

Thereafter, the porous Si layer transferred onto the second substrate was selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The single crystal remained without being etched by Si, and the porous Si was selectively etched and completely removed using the single crystal Si as a material for the etch stop.

Thus, a single-crystal Si layer having a thickness of 0.2 μm was formed on the Si oxide film. There was no change in the single crystal Si layer even by selective etching of the porous Si. When the film thickness of the formed single crystal Si layer was measured at 100 points over the entire surface, the uniformity of the film thickness was 200.
nm ± 5 nm.

As a result of observation of a cross section by a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
Mean square roughness in the area of 50 μm square is about 0.2 nm
Was equivalent to a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result can be obtained by forming it on the surface of the second substrate or both.

Further, the porous Si remaining on the first substrate was also selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. After that, a surface treatment such as hydrogen annealing or surface polishing is performed and the first
The above process was repeated by using the substrate as a second substrate or as a second substrate.

(Example 6) (Shaking the nozzle neck) Anodization was performed on a P-type first single-crystal Si substrate having a specific resistance of 0.01 Ω · cm in an HF solution.

The anodizing conditions were as follows.

Current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1:
1 hour: 11 (min) Thickness of porous Si: 12 (μm)

The porous Si is to be used as a separation layer in order to form a high quality epitaxial Si layer.

This substrate was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm. The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, as an insulating layer, a 200 nm oxide film (Si) was formed on the surface of the epitaxial Si layer by thermal oxidation.
O ₂ layer).

The surface of the SiO ₂ layer and the surface of a separately prepared Si substrate were overlapped and brought into contact with each other, and then subjected to a heat treatment at a temperature of 1180 ° C. for 5 minutes to perform bonding.

[0213] The bonded substrate formed as described above was separated using the apparatus shown in FIG. As shown in FIG.
The bonded wafer 301 is set up vertically, and the water jet device 0.15 mm nozzle 30 disposed above the gap formed by beveling of both wafers is placed above the gap.
High pressure pure water at a pressure of 2 to 2000 kgf / cm ² ,
The spray was performed from a direction parallel to the bonding interface (surface) of the bonded wafer. Then, when the nozzle 302 and the nozzle are swung in a fan shape in a plane on the same plane as the bonding surface of the wafer, the flow of the jet is also swung in this plane.

Thus, the wafer was divided into two via the porous Si layer. As a result, a part of the SiO ₂ layer, the epitaxial Si layer, and the porous Si layer originally formed on the surface of the first substrate were transferred to the second substrate side. Only porous Si remained on the surface of the first substrate.

Thereafter, the porous Si layer transferred onto the second substrate was selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The single-crystal Si remained without being etched, and the porous Si was selectively etched and completely removed using the single-crystal Si as a material for an etch stop.

That is, a single-crystal Si layer having a thickness of 0.2 μm was formed on the Si oxide film. There was no change in the single crystal Si layer even by selective etching of the porous Si. When the thickness of the formed single crystal Si layer was measured at 100 points over the entire surface in the plane, the uniformity of the film thickness was 201.
nm ± 4 nm.

As a result of observation of a cross section by a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
Mean square roughness in the area of 50 μm square is about 0.2 nm
Was equivalent to a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result can be obtained by forming it on the surface of the second substrate or both.

The porous Si remaining on the first substrate was also selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. After that, a surface treatment such as hydrogen annealing or surface polishing is performed and the first
The above-described steps were repeated using the same substrate or the second substrate.

When the wafer on which the separation layer was formed was separated as in Examples 2 to 4, similar results were obtained.

Example 7 (Rotation of Wafer) A P-type first single-crystal Si substrate having a specific resistance of 0.01 Ω · cm was anodized in an HF solution.

Anodizing conditions were as follows.

Current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₂ OH = 1: 1:
1 hour: 11 (min) Thickness of porous Si: 12 (μm)

The porous Si is intended to be used as a separation layer in order to form a high-quality epitaxial Si layer.

This substrate was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm. The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, as an insulating layer, a 200 nm oxide film (Si) was formed on the surface of the epitaxial Si layer by thermal oxidation.
O ₂ layer).

The second S prepared separately from the surface of the SiO ₂ layer
After overlapping and contacting the surface of the i-substrate, 1180
Heat treatment was performed at a temperature of 5 ° C. for 5 minutes, and bonding was performed.

The bonded substrate formed as described above was separated using the apparatus shown in FIG.

[0231] The bonded wafer 401 is supported and supported vertically from both sides.

First, the bonded wafer 401 is set so as to follow the positioning pins 413,
Was held. The stuck 401 is the positioning pin 41
3, the nozzle 402 was moved in the vertical direction of the uppermost portion of the wafer 401, and the distance between the bonded wafer 401 and the nozzle 402 was set to 15 mm. Next, the wafer 401 attached to the holding body 403 was moved leftward along the bearing 411 until the wafer 401 was attracted / held.

Next, water containing no abrasive particles was fed from the water jet pump 414 to the nozzle 402, and was continuously discharged for a certain period of time until the jetted water became stable. When the water becomes stable, the shutter 406 is opened and the bonded wafer 4
High-pressure pure water spouted from the nozzle 402 was applied to the center of the side surface of No. 01 in the thickness direction. At this time, by rotating the holder 404, the bonded wafer 401 and the holder 403 were rotated. The high-pressure water also entered the porous Si layer portion, and the bonded wafer 401 was spread out into two bodies, and finally separated into two bodies.

Thereafter, the porous Si layer transferred onto the second substrate was selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The single-crystal Si remained without being etched, and the porous Si was selectively etched and completely removed using the single-crystal Si as a material for an etch stop.

That is, a single crystal having a thickness of 0.2 μm was formed on the Si oxide film. There was no change in the single crystal Si layer even by selective etching of the porous Si. The film thickness of the formed single crystal Si layer was measured at 100 points over the entire surface of the plane, and the uniformity of the film thickness was 20 points.
0 nm ± 3 nm.

As a result of observation of a cross section by a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
Mean square roughness in the area of 50 μm square is about 0.2 nm
Was equivalent to a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result can be obtained by forming it on the surface of the second substrate or both.

The porous Si remaining on the first substrate was also selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. After that, a surface treatment such as hydrogen annealing or surface polishing is performed and the first
The above-described steps could be repeated by using this as a substrate or as a second substrate.

When the wafer on which the separation layer was formed was separated as in Examples 2 to 4, similar results were obtained.

(Example 8) (From an oblique direction) A first P-type single crystal Si substrate having a specific resistance of 0.01 Ω · cm was anodized in an HF solution.

The anodizing conditions were as follows.

Current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1:
1 hour: 11 (min) Thickness of porous Si: 12 (μm)

The porous Si is to be used as a separation layer in order to form a high quality epitaxial Si layer.

[0245] The thickness of the porous Si layer is not limited to this, and can be used from several hundreds of μm to several tens of μm.

This substrate was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm. The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, a 200 nm oxide film (SiO 2 film) was formed on the surface of this epitaxial Si layer as an insulating layer by thermal oxidation.
₂ layers).

A second S prepared separately from the surface of the SiO ₂ layer
After overlapping and contacting the surface of the i-substrate, 1180
Heat treatment was performed at a temperature of 5 ° C. for 5 minutes, and bonding was performed.

The bonded wafers are set upright, and the gap formed by beveling of both wafers is placed in a gap of 0.15 mm of a water jet device placed above the gap.
, High-pressure pure water was sprayed from the nozzle having a pressure of 2000 kgf / cm ² from a direction having an angle α to the bonding interface (surface) of the bonded wafer.

The wafer was held by an apparatus as shown in FIG. 4, and its nozzles were arranged as shown in FIG.

Thereafter, the porous Si layer transferred onto the second substrate was selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The single-crystal Si remained without being etched, and the porous Si was selectively etched and completely removed using the single-crystal Si as a material for an etch stop.

That is, a single-crystal Si layer having a thickness of 0.2 μm was formed on the Si oxide film. There was no change in the single crystal Si layer even by selective etching of the porous Si. When the thickness of the formed single crystal Si layer was measured at 100 points over the entire surface in the plane, the uniformity of the film thickness was 201.
nm ± 4 nm.

As a result of observation of a cross section by a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
Mean square roughness in the area of 50 μm square is about 0.2 nm
Was equivalent to a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result was obtained whether it was formed on the surface of the second substrate or on both.

Further, the porous Si remaining on the first substrate was also selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. After that, a surface treatment such as hydrogen annealing or surface polishing is performed and the first
The above-described steps were repeated using the same substrate or the second substrate.

When the wafer having the separation layer formed thereon was separated as in Examples 2 to 4, similar results were obtained.

Example 9 (Plural Jets) A P-type first single-crystal Si substrate having a specific resistance of 0.01 Ω · cm was anodized in an HF solution.

Anodizing conditions were as follows.

Current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1:
1 hour: 11 (min) Thickness of porous Si: 12 (μm)

The porous Si is to be used as a separation layer in order to form a high quality epitaxial Si layer.

The thickness of the porous Si layer is not limited to this, and can be used from several hundred μm to several tens μm.

This substrate was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm. The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, a 200 nm SiO ₂ layer was formed on the surface of the epitaxial Si layer by thermal oxidation.

The second S prepared separately from the surface of the SiO ₂ layer
After overlapping and contacting the surface of the i-substrate, 1180
Heat treatment was performed at a temperature of 5 ° C. for 5 minutes to perform bonding.

The bonded substrate formed as described above was separated using the apparatus shown in FIG.

As shown in FIG. 9, the bonded wafer 701
Was held upright from both sides of the wafer by a wafer holder 708. A 0.15 mm nozzle 70 of three water jet devices disposed above or beside the gap formed by beveling the two wafers 701.
High-pressure pure water was sprayed at a pressure of 2-704 to 2000 kgf / cm ² from a direction parallel to the bonding interface (surface) of the bonded wafer. A plurality of nozzles were scanned in a direction in which high-pressure pure water moved along a gap formed by beveling.

As a result, the wafer was divided into two parts via the porous Si layer.

As a result, the SiO ₂ layer, the epitaxial Si layer, and the porous S
Part of the i-layer was transferred to the second substrate side. Only porous Si remained on the surface of the first substrate.

Thereafter, the porous Si layer transferred onto the second substrate was selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The single-crystal Si remained without being etched, and the porous Si was selectively etched and completely removed using the single-crystal Si as a material for an etch stop.

Thus, a single-crystal Si layer having a thickness of 0.2 μm was formed on the Si oxide film. There was no change in the single crystal Si layer even by selective etching of the porous Si. When 100 points were measured on the entire in-plane thickness of the formed single crystal Si layer, the uniformity of the thickness was 201.
nm ± 4 nm.

As a result of observation of a cross section by a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
Mean square roughness in the area of 50 μm square is about 0.2 nm
Was equivalent to a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result can be obtained by forming it on the surface of the second substrate or both.

The porous Si remaining on the first substrate was also selectively etched while stirring with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. After that, a surface treatment such as hydrogen annealing or surface polishing is performed and the first
The above-described steps were repeated using the same substrate or the second substrate.

When the wafer on which the separation layer was formed was separated as in Examples 2 to 4, similar results were obtained.

Also, in the water jet injection method as in the above-described Embodiments 5 to 8, the use of a plurality of nozzles enables efficient separation of the bonded wafer.

Example 10 (Slit Jet) A P-type first single-crystal Si substrate having a specific resistance of 0.01 Ω · cm was anodized in an HF solution.

Anodizing conditions were as follows.

Current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1:
1 hour: 11 (min) Thickness of porous Si: 12 (μm)

The porous Si is for forming a high-quality epitaxial Si layer and for further use as a separation layer.

[0284] The thickness of the porous Si layer is not limited to this, and can be used from several hundreds of μm to several tens of μm.

This substrate was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm. The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ Gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, as an insulating layer, a 200 nm oxide film (Si) was formed on the surface of the epitaxial Si layer by thermal oxidation.
O ₂ layer) was formed.

The second S prepared separately from the surface of the SiO ₂ layer
After overlapping and contacting the surface of the i-substrate, 1180
Heat treatment was performed at a temperature of 5 ° C. for 5 minutes to perform bonding.

The bonded substrate formed as described above was separated using the apparatus shown in FIG. As shown in FIG. 10, the bonded wafers are set upright, and 0.15 of a water jet device disposed above or beside the gap formed by beveling the two wafers.
80 mm from a slit-shaped nozzle with a width of 50 mm and a length of 50 mm
High-pressure pure water was sprayed at a pressure of 0 kgf / cm ² from a direction parallel to the bonding interface (surface) of the bonded wafer. The slit was arranged in parallel with the bonding interface (surface) of the bonded wafers, and a linear water flow was properly jetted into a gap formed by beveling of both wafers. And
A plurality of nozzles were scanned in a direction in which high-pressure pure water moved along a gap formed by beveling.

As a result, the wafer was divided into two parts via the porous Si layer.

As a result, the SiO ₂ layer, the epitaxial Si layer, and the porous S
Part of the i-layer was transferred to the second substrate side. Only porous Si remained on the surface of the first substrate.

Thereafter, the porous Si layer transferred to the second substrate was selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The single-crystal Si remained without being etched, and the porous Si was selectively etched and completely removed using the single-crystal Si as a material for an etch stop.

That is, a single-crystal Si layer having a thickness of 0.2 μm was formed on the Si oxide film. There was no change in the single crystal Si layer even by selective etching of the porous Si. When the thickness of the formed single crystal Si layer was measured at 100 points over the entire surface in the plane, the uniformity of the film thickness was 201.
nm ± 4 nm.

As a result of observation of a cross section by a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed in hydrogen at 1100 ° C. for 1 hour, and the surface roughness was evaluated by an atomic force microscope.
Mean square roughness in the area of 50 μm square is about 0.2 nm
Was equivalent to a commercially available Si wafer.

The oxide film is not on the surface of the epitaxial layer,
The same result can be obtained by forming it on the surface of the second substrate or both.

The porous Si remaining on the first substrate was also selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. Then, hydrogen annealing or surface treatment of the surface polishing layer is performed, and the first polishing is performed again.
As a second substrate or as a second substrate.

When the wafer on which the separation layer was formed as in Examples 2 to 4 was separated, similar results were obtained.

Example 11 (Quartz Substrate) As a second substrate, a light-transmitting substrate (quartz) was prepared.

Before the bonding, the quartz surface was subjected to N ₂ plasma treatment, and heat treatment was performed at 400 ° C. for 100 hours. Then, heat treatment in hydrogen for flattening the surface of the SOI layer after the separation was performed at 970 ° C. which is 1000 ° C. or lower for 4 hours.

The other steps are the same as those in Examples 1 to 10 described above.

As described above, when a transparent substrate made of an insulating material is used as the second substrate, an oxide film (an insulating film) formed on the surface of the epitaxial Si layer in the above-described Examples 1 to 10 is used. Layer) is not necessary. However, in order to separate the epitaxial Si layer on which an element such as a transistor is formed later from the bonding interface and reduce the influence of impurities on the interface, it is desirable to form the oxide film (insulating layer).

(Example 12) (GaAs on Si) In the same manner as in Examples 1 to 10, even when the epitaxial layer was formed of a compound semiconductor represented by GaAs.

In the above-described embodiment, the water jet pressure and the nozzle diameter are 500 to 35, respectively.
It could be realized in the same manner between 00 kgf / sm ² , 0.1 mm and (half of the total thickness of the bonded wafer).

The method of epitaxially growing GaAs on porous Si can be carried out by various methods such as MBE, sputtering, liquid phase growth, etc. in addition to CVD, and is not limited to CVD.
Further, the film thickness can be from several nm to several hundred μm.

In each of the above embodiments, 49% hydrofluoric acid and 3%
Not only a mixture with 0% hydrogen peroxide solution, but also hydrofluoric acid, hydrofluoric acid + alcohol, hydrofluoric acid + alcohol + hydrogen peroxide water, buffered hydrofluoric acid, buffered hydrofluoric acid + alcohol, buffered hydrofluoric acid + peroxide Porous Si can be selectively etched due to its enormous surface area even with a hydrogen oxide solution, a buffered hydrofluoric acid + alcohol + hydrogen peroxide solution, or a mixed solution of hydrofluoric acid / nitric acid / acetic acid.

The other steps can be carried out not only under the conditions limited to the embodiment but also under various conditions.

(Example 13) (Wafer rotation) A disk-shaped wafer made of P-type single-crystal Si having a specific resistance of 0.01 Ω · cm was prepared as a first Si substrate, and the surface thereof was placed in an HF solution. Anodizing treatment was performed.

The anodizing conditions were as follows.

Current density: 7 (mA · cm ⁻² ) Anodizing solution: HF: H ₂ O: C ₂ H ₅ OH = 1: 1:
1 hour: 11 (min) Thickness of porous Si: 12 (μm)

This wafer was oxidized in an oxygen atmosphere at 400 ° C. for 1 hour. Due to this oxidation, the inner wall of the porous Si hole was covered with the thermal oxide film. The surface of the porous Si layer is treated with hydrofluoric acid to remove only the oxide film on the surface of the porous Si layer while leaving the oxide film on the inner wall of the hole. The epitaxial growth was performed by 0.3 μm.
The growth conditions are as follows.

Source gas: SiH ₂ Cl ₂ / H ₂ gas flow rate: 0.5 / 180 l / min Gas pressure: 80 Torr Temperature: 950 ° C. Growth rate: 0.3 μm / min

Further, as an insulating layer, a 200 nm oxide film (Si) was formed on the surface of the epitaxial Si layer by thermal oxidation.
O ₂ layer).

A disc-shaped Si wafer was prepared as a second Si substrate separately from the first substrate thus obtained.

The surface of the SiO ₂ layer of the first Si substrate and the surface of the second Si substrate were overlapped and brought into contact with each other.
A heat treatment was performed at a temperature of 180 ° C. for 5 minutes to bond the two substrates together.

Next, preparations were made to separate the composite member composed of the bonded wafers using the apparatus shown in FIGS. 14, 15, and 17 to 20.

The wafer, which is a composite member, was placed upright in accordance with the notch of the positioning table 35.

[0318] The air pressurized from the tubes 52 and 54 is supplied to the pressurizing path 56, and the holding parts 45a, 46a
18 is directed toward the front surface and the back surface of the wafer as shown in FIG. 18, and the holding surfaces of the holding portions 45a and 46a having the openings op contact the front surface and the back surface of the wafer, respectively.

The wafer was suctioned from the tubes 51 and 53, and the wafer was fixed to the holders 45a and 46a.

The supply of the pressurized air is interrupted, and the spring 4
A tension of 7,48 was applied.

With the shutter 61 closed, the pump 6
From No. ² , pure water containing no abrasive particles was pumped to a nozzle having a diameter of 0.15 mm, and the pump 62 was operated so as to inject water at a pressure of about 200 kgf / cm ² .

The positioning table 35 is retracted to the standby position, and the motor 32 is energized so that the shaft 31 and the belt 2
The holders 21 and 22 were rotated by the rotational driving force transmitted via the switches 7 and 28.

Since the wafers are attracted to the holders 45a and 46a, they started to rotate simultaneously with the holders 21 and 22 in the same direction at the same angular velocity.

[0324] As shown in Fig. 19, the shutter 61 was opened, and a water jet was applied to the separation portion on the side surface of the wafer.

[0325] Water from the water jet penetrated into the holes at the separation location, and separated the wafer from its surroundings at the porous layer serving as the separation location.

As the jetting of the water jet and the rotation of the wafer are continued, the gap formed by the separation gradually grows from the periphery of the wafer to the center of rotation, and finally, as shown in FIG.
The wafer could be separated as shown in FIG.

Since the wafer is subjected to a force in the directions indicated by arrows TA and TB in FIG. 20, the center of rotation of the wafer is finally separated and the wafer separates as shown in FIG.

Thereafter, the water supply was interrupted, and the separated wafers were removed from the holders 45a and 46a.

Then, the remaining portion of the porous Si layer transferred onto the second substrate was selectively etched while being stirred with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. The transferred single crystal Si under the porous layer remains without being etched, and the porous Si is selectively etched and completely removed using the single crystal Si as a material for an etch stop. It was exposed.

Thus, a first SOI substrate having a single-crystal Si layer having a thickness of 0.2 μm on the Si oxide film of the second substrate was obtained. There was no change in the single crystal Si layer even by selective etching of the porous Si. The film thickness of the formed single-crystal Si layer was measured at 100 points over the entire in-plane surface.
Met.

As a result of observing the cross section with a transmission electron microscope,
No new crystal defects were introduced into the i-layer, and it was confirmed that good crystallinity was maintained.

Further, a heat treatment was performed at 1100 ° C. in hydrogen for 50 hours.
Minutes, and the surface roughness was evaluated with an atomic force microscope. The average square roughness in a 50 μm square area was approximately 0.2
nm.

The porous Si remaining on the first substrate was also selectively etched while stirring with a mixed solution of 49% hydrofluoric acid and 30% hydrogen peroxide. Thereafter, a surface treatment such as polishing was performed.

The polished first substrate was again subjected to anodization to form a porous Si layer, on which non-porous single-crystal Si was grown. The surface of the non-porous single-crystal Si layer epitaxially grown was oxidized. Then, a separately prepared third substrate, ie, a Si wafer, was bonded to the oxidized surface of the single crystal Si layer of the first substrate.

The conditions of the above steps are the same as the conditions for manufacturing the first bonded wafer. Again the first
The wafer is separated in the same manner as the second separation method, and the second SOI having a single-crystal Si layer on the insulating surface of the third substrate
A substrate was obtained. By repeating the above steps and recycling the first substrate, the third and fourth SOI
A substrate was manufactured.

[0336]

As described above, according to the present invention, it is possible to separate a composite member having a separation area into a plurality of small members in the separation area without damaging or damaging the other parts than the separation area. By utilizing this, it becomes possible to easily and surely manufacture a semiconductor substrate of higher quality than ever before with a high yield.

[Brief description of the drawings]

FIG. 1 is a schematic view for explaining a method for separating a composite member according to the present invention.

FIG. 2 is a schematic diagram for explaining an example of a method for separating a composite member using a fluid according to the present invention.

FIG. 3 is a perspective view showing an example of the separation device of the present invention.

FIG. 4 is a sectional view showing another example of the separation device of the present invention.

FIG. 5 is a perspective view showing another example of the separation device of the present invention.

FIG. 6 is a schematic view showing still another example of the separation device of the present invention.

FIG. 7 is a schematic view showing still another example of the separation device of the present invention.

FIG. 8 is a schematic view for explaining another example of the method for separating a composite member using a fluid according to the present invention.

FIG. 9 is a schematic view showing still another example of the separation device of the present invention.

FIG. 10 is a schematic view showing still another example of the separation device of the present invention.

FIG. 11 is a schematic view showing still another example of the separation device of the present invention.

FIG. 12 is a schematic view showing still another example of the separation device of the present invention.

FIG. 13 is a schematic view showing still another example of the separation device of the present invention.

FIG. 14 is a top view of another separation device of the present invention.

FIG. 15 is a side view of the separation device shown in FIG.

FIG. 16 is a schematic diagram for explaining the state of separation of the composite member.

FIG. 17 is a sectional view of the separation device shown in FIG. 15 in a standby state.

FIG. 18 is a sectional view of the separation device shown in FIG. 15 in a substrate holding state.

FIG. 19 is a sectional view of the separation device shown in FIG. 15 in a separation operation start state.

FIG. 20 is a sectional view of the separation device shown in FIG. 15 in a state at the end of the separation operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st member 2 2nd member 3 Separation area 5 Layer area 6 Side surface (end surface) 7 Fluid 8 Nozzle 14 Joining interface

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[Procedure amendment]

[Submission date] May 25, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

41. A composite member separating method for separating a composite member having a plurality of members joined to each other in a separation region including a minute gap at a position different from a joint portion of the plurality of members, comprising: Separating the composite member by spraying a fluid containing no abrasive particles on the side surface of the composite member. ────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] October 9, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Patent application title: Method of separating composite member, separated part
Material, separation device , method of manufacturing semiconductor substrate, and semiconductor substrate

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0023

[Correction method] Change

[Correction contents]

[0023]

According to the present invention, there is provided a method for separating a composite member having a plurality of members joined to each other at a portion different from a joint portion of the plurality of members. The concave or narrow gap of the member
The composite member is separated by spraying a fluid on the side surface having the composite member. The invention is bonded to each other
A composite member having a plurality of members
A composite member that separates at a location different from the joint
The high-pressure water stream from the nozzle in the separation method
The water jet method is applied to the front side of the composite member.
The composite member is separated by spraying the current.
It is characterized by that. The present invention relates to a method for manufacturing a semiconductor substrate.
Wherein a porous single crystal semiconductor layer and a porous single crystal semiconductor layer are formed on a substrate.
Non-porous single crystal semiconductor layer provided on crystal semiconductor layer
Preparing a first substrate having: the first substrate
And a second substrate, and a concave or narrow gap on the side
Forming a composite member having:
Spraying a fluid on the side surface of the porous single crystal semiconductor layer
With the above, the composite member in the porous single crystal semiconductor layer
It has a separating step. The present invention
A method for producing a conductive substrate, comprising: forming a porous single crystal half on a substrate.
A non-multi layer provided on the conductor layer and the porous single crystal semiconductor layer;
Step of preparing a first base having a porous single crystal semiconductor layer
The first substrate and the second substrate are bonded together to form a composite
The process of forming the member, and blowing high-pressure water flow from the nozzle
The composite member by the water jet method
Spraying the water stream on the side surface of the porous single crystal semiconductor layer
With the above, the composite member in the porous single crystal semiconductor layer
It has a separating step. The present invention
A method for manufacturing a conductive substrate, comprising:
By implanting ions at a predetermined depth in one substrate,
Form ion-implanted layer to obtain microbubble layer
Performing the step of: interposing an insulating layer between the first base and the second base.
Forming a composite member by bonding
Spraying fluid on the side of the ion implantation layer of the composite
Separates the composite member in the ion-implanted layer
Characterized by a step of performing The present invention provides a separation device
Unit having a plurality of members joined together
Support means for supporting the material, concave or narrow gap of said composite member
Having a spraying means for spraying a fluid to the side surface having a gap
And at a location different from the joining location of the plurality of members.
The composite member is separated. The present invention
First part of a composite member having a plurality of members joined together
The surface is rotatably held by a first holding body;
A second surface of the material is rotatably held by a second holding body,
Rotating the first and second holders in synchronization,
Fluid at a separation location different from the joint location of the composite member
And the fluid was sprayed on the composite member.
It is characterized by being separated into multiple members starting from the point
I do. TECHNICAL FIELD The present invention relates to a separation device, and relates to a multi-piece bonded to each other.
A first surface of a composite member having a number of members is rotatably held.
The first holder to be rotated, the second surface of the composite member can be rotated
Of the first and second holding bodies,
Synchronizing means for synchronizing rotation, contact of the rotating composite member
A nozzle that sprays fluid to a separation point different from the joint
Having a location where the fluid is sprayed on the composite member.
It is characterized by being separated into a plurality of members as a starting point. Book
The invention provides a composite member having a plurality of members joined together.
At a location different from the joining location of the plurality of members.
In the separation area including small voids,
In the separating method, a concave or narrow gap of the disc-shaped composite member is provided.
Abrasive-free fluid is sprayed on the side with gaps
Thereby separating the composite member.
You.

Continuation of front page (72) Inventor Takao Yonehara 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (41)

[Claims] 1. A method for separating a composite member having a plurality of members joined to each other at a portion different from a joint portion of the plurality of members, wherein a fluid is sprayed on a side surface of the composite member. And separating the composite member. 2. The composite member according to claim 1, wherein the composite member has a separation region including a minute space inside one member, and separates the separation region into a plurality of members by spraying a fluid near the separation region. Separation method as described. 3. The separation method according to claim 2, wherein a concave shape is formed in the vicinity of the separation region so as to generate a force for receiving the fluid and expanding the separation region. 4. The separation method according to claim 2, wherein the separation region has weaker mechanical strength than the joint. 5. The separation method according to claim 2, wherein the separation region comprises a porous layer formed by an anodizing method. 6. The separation method according to claim 2, wherein the separation region is a layer from which microbubbles formed by ion implantation can be obtained. 7. The separation method according to claim 1, wherein the method of spraying the fluid uses a water jet method in which a high-pressure water stream is blown from a nozzle. 8. A member separated by the separation method according to claim 1. 9. A step of preparing a first base having a porous single-crystal semiconductor layer on a substrate and a non-porous single-crystal semiconductor layer provided on the porous single-crystal semiconductor layer; 1
Bonding the base member and the second base member to form a composite member, and spraying the composite member with a porous single crystal semiconductor layer by spraying a fluid near the porous single crystal semiconductor layer of the composite member. 3. A method for manufacturing a semiconductor substrate, comprising the step of separating the substrate. 10. A concave shape is formed in the vicinity of the porous single crystal semiconductor layer of the composite member so as to generate a force in a direction of expanding the porous single crystal semiconductor layer by receiving a fluid flow. 3. The method for producing a semiconductor substrate according to item 1. 11. The method according to claim 9, wherein the porous single crystal semiconductor layer has a weaker mechanical strength than a bonding surface of the first base and the second base. 12. The method according to claim 9, wherein the porous single-crystal semiconductor layer is formed by an anodizing method. 13. The method of manufacturing a semiconductor substrate according to claim 9, wherein the method of spraying the fluid uses a water jet method in which a high-pressure water stream is blown from a nozzle. 14. A first substrate, wherein a single-crystal silicon substrate is partially made porous to form a porous single-crystal silicon layer, and a non-porous single-crystal silicon layer is formed on the porous single-crystal silicon layer. The method for manufacturing a semiconductor substrate according to claim 9, wherein the layer is formed by epitaxially growing a layer. 15. The first substrate and the second substrate are bonded together via at least one insulating layer, and the insulating layer is formed by oxidizing a surface of the non-porous single-crystal silicon layer. A method for manufacturing a semiconductor substrate according to claim 14. 16. The method according to claim 9, wherein the second base comprises a light-transmitting substrate. 17. The method according to claim 9, wherein the second base is made of a silicon substrate. 18. A step of forming an ion-implanted layer from which a microbubble layer can be obtained by implanting ions into a predetermined depth of a first base made of a single crystal semiconductor, wherein the first base and the second base are formed. Forming a composite member by laminating the substrate with an insulating layer, and separating the composite member in the ion-implanted layer by spraying a fluid near the ion-implanted layer of the composite member. A method for manufacturing a semiconductor substrate, comprising: 19. The method of manufacturing a semiconductor substrate according to claim 18, wherein a concave shape is formed near the ion-implanted layer of the composite member so as to generate a force in a direction of receiving the fluid and expanding the ion-implanted layer. 20. The method according to claim 18, wherein the ion-implanted layer has weaker mechanical strength than a bonding surface of the first base and the second base. 21. The method for manufacturing a semiconductor substrate according to claim 18, wherein the method of spraying the fluid uses a water jet method of blowing a high-pressure water stream from a nozzle. 22. A semiconductor substrate produced by the method according to claim 9. 23. A separation apparatus for executing the separation method according to claim 1. 24. The separation apparatus according to claim 23, wherein the fluid is blown by a water jet method in which a high-pressure water stream is blown from a nozzle. 25. The separation device according to claim 24, wherein the water stream is scanned by relatively moving the composite member and the nozzle. 26. The water stream is scanned by fixing the composite member and scanning the nozzle.
6. The separation device according to 5. 27. A holder for holding the composite member, a nozzle horizontal movement mechanism for horizontally moving the nozzle along the joint of the composite member, and a vertical distance between the composite member and the nozzle. 27. The separation device according to claim 26, further comprising a nozzle vertical movement mechanism that adjusts the pressure. 28. The separation device according to claim 26, further comprising a mechanism that scans the nozzle in a fan shape around a fulcrum. 29. The separation device according to claim 26, wherein the nozzle rotates around the composite material around the composite material. 30. The separation device according to claim 26, wherein the nozzle includes a plurality of nozzles. 31. The water stream is scanned by scanning the composite member and fixing the nozzle.
6. The separation device according to 5. 32. The separation device according to claim 31, further comprising a rotation mechanism for rotating the composite member. 33. The separation device according to claim 32, wherein the nozzle is positioned toward a rotation center of the composite member. 34. The separation device according to claim 32, further comprising a rotation holding member that holds a rotation center of the composite member. 35. A composite member having a plurality of members joined to each other, a first surface of the composite member is rotatably held by a first holder, and a second surface of the composite member is rotated by a second holder. Holding, rotating the first and second holding bodies in synchronization with each other, spraying a fluid on an end face of the rotating composite member, and starting from the place where the fluid is sprayed on the composite member, a plurality of A separation method, comprising separating into members. 36. The separation method according to claim 35, wherein the fluid is blown to a separation location different from a joining location of the composite member. 37. The separation method according to claim 35, wherein a concave portion is provided on an end surface of the composite member, and the fluid is blown to a bottom portion of the concave portion. 38. A first holder for rotatably holding a first surface of a composite member having a plurality of members joined to each other, and a second holder for rotatably holding a second surface of the composite member.
Holding member, a synchronizing means for synchronizing the rotation of the first and second holding members, a nozzle for spraying a fluid to an end face of the rotating composite member, and a plurality of the composite members starting from a location where the fluid is sprayed. A separation device, wherein the separation device separates the members. 39. The separation apparatus according to claim 38, further comprising means for determining the position of the nozzle so as to spray the fluid to a separation point different from a connection point of the composite member. 40. The separation apparatus according to claim 38, wherein a concave portion is provided on an end surface of the composite member, and the device has means for positioning the nozzle so as to spray the fluid to a bottom portion of the concave portion. 41. A composite member separating method for separating a composite member having a plurality of members joined to each other in a separation region including a minute gap at a position different from a joint portion of the plurality of members, Separating the composite member by spraying a fluid containing no abrasive particles on the side surface of the composite member.