JP4529036B2 - Manufacturing method of thin film wafer for semiconductor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a semiconductor thin film wafer, and more particularly to a manufacturing method suitable for manufacturing a bonded semiconductor thin film wafer or a SIMOX semiconductor thin film wafer.
[0002]
[Prior art]
With the high integration, high performance, multi-functionality, and high reliability of semiconductor integrated circuits, pattern dimensions are becoming increasingly finer. Accordingly, there has been a demand for a semiconductor wafer having a semiconductor thin film (hereinafter referred to as an SOI layer) thinned to a defect-free 100 nm or 200 nm thickness by separating an oxide film on a wafer surface layer serving as a device formation region. Development of wafers for semiconductors such as SIMOX, which has an active wafer to be thinned in accordance with the thickness of the wafer and a support wafer, or a wafer with oxygen ions implanted to form a buried oxide film layer at a certain depth from the surface Is underway. In the thinning process of the bonded wafer, the active wafer side is processed by machining, chemical etching, vapor phase etching, or the like, or hydrogen ions are implanted into the active wafer, and the wafer is parallel to the surface starting from this implanted layer. It is known to use the smart cut method of dividing by.
[0003]
These manufacturing methods are
(1) Generally, in a bonded SOI wafer, as shown in FIG. 7 to be described later, the active wafer 11 has a predetermined thickness obtained by oxidizing one surface 11a after mirror polishing (hereinafter referred to as mirror polishing). After the oxide film 15 is formed, it is bonded to the mirror-finished support wafer 12 at a predetermined bonding temperature, and heat treatment is performed to obtain a strong adhesion surface. After that, the active wafer 11 to be the SOI layer is thinned to a predetermined thickness by machining, chemical etching, vapor phase etching, etc., and the thin film SOI wafer 10 is manufactured.
(2) In the smart cut SOI, as shown in FIG. 10, the active wafer 51 and the support wafer 52 oxidize one of the surfaces 51 a and 52 a after mirror processing to form a predetermined oxide film 55. Next, hydrogen ions 57 are implanted into the active wafer, and then bonded to the support wafer 52 at room temperature or at a predetermined bonding temperature. After that, annealing is performed at about 500 ° C. to 600 ° C., divided by the hydrogen injection layer 57a, and annealing is performed at about 1000 ° C. or higher to obtain the smart cut SOI wafer 50.
(3) In a SIMOX wafer, although not shown, one surface of one wafer is mirror-finished and oxygen ions are implanted from the mirror-finished surface into a predetermined position in the wafer by implantation, and a buried oxide film is formed inside the wafer by high-temperature heat treatment. Thus, a SIMOX wafer is manufactured.
[0004]
[Problems to be solved by the invention]
However, in the conventional manufacturing method, in the mirror surface processing step, the surface of the wafer is a shallow scratch that can be observed for the first time by other methods such as parallel light, under a microscope, and etching. There are micro scratches or mechanical damage (mirror finish damage) of small holes. For this reason, conventionally, as shown in FIG. 11, the active wafer 61 is formed with a primary oxide film 63 in advance by a primary oxidation process after mirror-processing one surface 61a. As a result, the surface layer of the active wafer is oxidized to a predetermined depth together with mechanical damage 65 such as micro scratches and small holes. Then, the scratches were removed by the primary oxide film removing step, and then an oxide film 67 having a predetermined thickness was formed. However, it has been found that these damages remain without being sufficiently removed by the primary oxide film removal step. This mechanical damage 65 is caused by forming through defects 69 penetrating through the silicon thin film when the active wafer 61 is thinned by machining, chemical etching, or vapor phase etching to a predetermined thickness after being bonded to the support wafer 62, and SOI The semiconductor device manufactured from the wafer 60 is deteriorated in electrical characteristics, and the yield is lowered.
[0005]
Also, in SIMOX wafers, when oxygen ions are implanted into a wafer that has micro scratches or mechanical damage of minute holes, the defects in the wafer are increased by the energy during implantation and the penetration defects are increased. It was discovered that
[0006]
The present invention pays attention to the above-mentioned conventional problems, and relates to a method for manufacturing a thin film wafer for semiconductors. In particular, by removing mechanical damage caused by mirror finishing, the electrical characteristics of semiconductor devices are improved and the yield is improved. An object of the present invention is to provide a method for manufacturing a semiconductor thin film wafer.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a method of manufacturing a semiconductor thin film wafer according to the present invention includes manufacturing a semiconductor wafer by oxidizing a surface of a mirror-polished active wafer and bonding it to a support wafer, and thinning the active wafer. In the method of manufacturing a thin film wafer for semiconductor, mechanical damage caused by the mirror polishing process is applied to the mirror polishing surface of the active wafer. By spin etching Apply the treatment to remove, this mechanical damage removal treatment surface Oxidize After bonding to the support wafer, the active wafer was thinned. Also, The machining allowance by the spin etching process may be set to a depth equivalent to or greater than the mechanical damage due to the mirror polishing.
[0008]
The mirror-finished wafer has mechanical damage such as micro scratches or minute holes. By removing this mechanical damage by the removal means using spin etching, the active wafer is thinned. Can also avoid the effects of damage. The machining allowance is generally set to a value greater than this value because the damage depth caused by mirror polishing is generally about 1 μm. Since the SOI wafer formed by laminating the damage removal surface of the active wafer to the support wafer is erased even when the active wafer is thinned, the electrical characteristics are improved. The yield can be improved without deteriorating.
[0009]
In addition, the above configuration is used when a thin film wafer is manufactured by performing machining, chemical etching, and vapor phase etching, or a hydrogen injection layer is formed by implanting hydrogen ions to a predetermined depth from the surface of the active wafer, and hydrogen implantation. The present invention can be applied to a case where a thin film wafer is manufactured by dividing into layers.
[0010]
Further, the present invention relates to a method for manufacturing a thin film wafer for semiconductor in which oxygen ions are implanted into a mirror-polished wafer to form a buried oxide film, and mechanical damage caused by the mirror-polishing treatment is applied to the mirror-polished surface. By spin etching It is possible to adopt a configuration in which a buried oxide film is formed by performing a removal process and then implanting oxygen ions.
[0011]
In such a configuration, since there are microscopic small holes generated by mirror polishing, oxygen ions are implanted into the wafer after mirror polishing, so that the small hole defects are increased by ion implantation energy, and penetrating defects are reduced. Although it is formed, the mirror surface processing damage is removed by spin etching before ion implantation, so that the generation of through defects itself can be reduced, and a thin film wafer with a high yield with very little electrical property deterioration can be manufactured. .
[0012]
According to the manufacturing method described above, mechanical damage of micro scratches or minute holes due to mirror finishing is completely removed by spin etching on the mirror finishing surface. Also, the etched surface obtained by spin etching, unlike other alkali etching, etc., has very good flatness and good surface microroughness. There is no. In addition, by using a mixed acid (hydrofluoric acid, nitric acid, sulfuric acid, phosphoric acid) having a high etching rate and uniform etching characteristics as the etchant, the flatness and microroughness of the spin-etched surface can be mirror-finished. The same accuracy as the surface is obtained, and the adhesive strength in the bonded state is naturally kept good. In addition, when the thickness of the intermediate oxide film layer is 6000 mm or less, the effect of removing mechanical damage by spin etching is exhibited, and the effect is remarkably exhibited particularly when the thickness is 4000 mm or less.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Specific embodiments of a method for producing a semiconductor thin film wafer according to the present invention will be described below in detail with reference to the drawings.
[0014]
FIG. 1 is a flowchart showing a manufacturing process of a bonded SOI wafer. A silicon wafer to be a material for manufacturing an SOI wafer is provided after being mirror-finished (steps 100 and 200), one of which is a support wafer (step 110) and the other is an active wafer (step 212). The silicon wafer that is the active wafer has a bonding surface to the support wafer and a surface side on which a circuit is formed by thin film processing. In particular, spin etching processing should be performed on the mirror-finished surface on the bonding surface side. (Step 210). In this spin etching, mixed acid (hydrofluoric acid, nitric acid, sulfuric acid, phosphoric acid) is used as an etching solution, and this etching solution is dropped on the upper surface of a rotating silicon wafer using a supply nozzle, and etching processing is performed using the rotation of the wafer. To do. In such spin etching, when a small hole having a certain depth exists on the wafer surface, as shown in FIG. 2, the etching solution flows through the surface layer by centrifugal force and enters the small hole 10. Etching without removing the so-called land portion of the wafer 12 where the small holes 10 existed in this place as shown in FIG. 5A is removed (FIG. 5B), and the size of the small holes 10 is gradually increased. Etching is performed to make it smaller, and the small holes 10 are eventually eliminated ((c) in the figure). On the other hand, in the immersion etching performed by immersing the wafer 12 in the etching solution, as shown in FIG. 3, the etching solution enters the inside of the small hole 10, and as shown in FIG. Etching is also performed on the inner wall surface of the small hole 10 together with the so-called land portion of the wafer 12 in which the small hole 10 was present (FIG. 5B), and the surface is maintained while maintaining the surface shape including the small hole 10. Etching eventually enlarges the small hole 10 ((c) in the figure). Therefore, it is desirable to use spin etching that performs surface etching without enlarging the small holes 10 in order to realize a function of eliminating micro scratches and smile holes generated by mirror finishing.
[0015]
The amount of etching by spin etching depends on the mechanical damage depth of micro scratches or microscopic holes by mirror finishing, but it may be set to an empirically obtained value. At present, the damage depth is about 1 μm. Therefore, it is sufficient to process to a depth greater than that.
[0016]
Thus, after spin etching is performed on the active wafer, surface oxidation is performed (step 214 in FIG. 1). This is for finally forming an insulating layer between the supporting wafer.
[0017]
After such processing, it may be performed in the same manner as a conventional process for producing a bonded SOI wafer. First, the support wafer and the surface-oxidized active wafer are washed and then bonded and integrated. (Step 300). Then, heat treatment is performed (step 310), the bonding surface is strengthened, thin film processing such as mechanical processing and chemical etching / vapor phase etching is performed (step 312), and a thin film SOI wafer is manufactured (step 314).
[0018]
FIG. 4 is a flowchart showing a process for producing a SIMOX wafer. The material silicon single crystal wafer is mirror-finished (step 400). Due to this mirror finishing, micro scratches or mechanical damages of minute holes are generated on the surface. In order to remove this damage, a spin-etching process is performed on the wafer that has been subjected to the mirror finishing, as in the above-described example (step 410). This spin etching process is performed until the etching rate reaches 1 μm or more, that is, to a depth that eliminates the mechanical damage. Then, after performing the spin etching, oxygen ions are implanted from the side of the spin etching surface to form a buried oxide film layer (step 412). Then, heat treatment such as annealing is performed (step 414) to obtain a thin film SOI wafer (step 416).
[0019]
As described above, in the embodiment of the present invention, it is generated by performing the mirror surface processing by performing the spin etching on the bonded surface of the mirror surface processed wafer, or in the case of the SIMOX wafer, the oxygen ion implantation surface. Mechanical damage such as micro scratches or minute holes is removed in advance. As a result, it is possible to suppress the generation of penetration defects due to the thinning process of the active wafer and the ion implantation process of the SIMOX wafer in the case of the bonded wafer, and the deterioration of the electrical characteristics of the semiconductor elements using the wafer and the product yield. Can be improved.
[0020]
【Example】
The manufacturing method of the SOI wafer and the SIMOX wafer was confirmed in the following examples and comparative examples. In order to evaluate the penetration defect density existing in the SOI layer of the thin-film SOI wafer and the SIMOX wafer, SiO formed by immersing the formed SOI wafer and the SIMOX wafer in a hydrogen fluoride solution and dissolving through the penetration defect. ₂ The number of pits (HF pits) was counted with a microscope.
[0021]
Example 1
A method of manufacturing the thin film SOI wafer according to the first embodiment of the present invention will be described based on the steps shown in FIG.
(A) Seven pairs of two semiconductor silicon wafers 1 and 2 (active wafer 1 and support wafer 2) having a diameter of 150 mm were prepared, and the mirror surface processing was applied to the surfaces 1a and 2a. On the mirror-finished surfaces 1 a and 2 a of the semiconductor silicon wafers 1 and 2, microscratches or microscopic small holes of 1 μm or less, usually caused by mirror finishing, are generated.
(B) The active wafer 1 is subjected to spin etching on the mirror-finished surface 1a to remove the mechanical scratches 3 caused by the micro-scratch or minute holes generated by the mirror-finishing. The machining allowance Gr of the mirror-finished surface 1a by spin etching was 5 μm with a margin to completely remove the mechanical damage 3. As an etchant used for this spin etching, a mixed acid (hydrofluoric acid, nitric acid, sulfuric acid, phosphoric acid) having a high etching rate and uniform etching characteristics was used. As a result, the flatness and microroughness of the spin etching processed surface 1b of the active wafer 1 are processed uniformly over the entire surface of the wafer, so that the same accuracy as that of mirror processing is obtained, and the adhesive strength is also kept good. .
(C) The seven active wafers 1 have intermediate oxide films 7 (SiO2) having different thicknesses of seven levels on the wafer surface. ₂ Film) is grown by thermal oxidation.
[0022]
The thickness levels of the intermediate oxide film 7 were set to (1) 0 mm, (2) 1000 mm, (3) 2000 mm, (4) 4000 mm, (5) 6000 mm, (6) 8000 mm, and (7) 10,000 mm.
(D) The active wafer 1 is bonded to the support wafer 2 on the spin etching processed surface 1b side where the spin etching is performed.
(E) The surface of the active wafer 1 bonded to the support wafer 2 is thinned by machining etching, chemical etching, and vapor phase etching. Thus, finally, a thin film SOI wafer 1A having a SOI layer thickness Ta of 1000 mm is manufactured. This thinning may be performed by a combination of mechanical etching and chemical etching, or mechanical etching and vapor phase etching.
(F) The 1000 Å thin film SOI wafer 1A is immersed in a hydrogen fluoride solution, and then SiO2 is used using a microscope. ₂ The number of pits (HF pits) was counted.
[0023]
As a result, as shown by the mark ● in FIG. 6, the HF pit density of the sample subjected to the spin etching is SiO 2 which becomes the intermediate oxide film 7. ₂ It was confirmed that a constant value was obtained regardless of the thickness of the film. This is because the mechanical damage 3 is removed by spin etching, and the HF defect density is constant and low at all levels. In addition, when spin etching is performed, there is no shallow mechanical damage 3 in which no penetrating defect is formed, and the device yield can be improved.
[0024]
(Comparative Example 1)
For comparison, a conventional thin film SOI wafer manufacturing method will be described with reference to FIG.
(G) Seven pairs of two semiconductor silicon wafers 11 and 12 (active wafer 11 and support wafer 12) having a diameter of 150 mm were prepared, and the mirror finish was applied to the surfaces 11a and 12a. On the mirror-finished surfaces 11a and 12a of the semiconductor silicon wafers 11 and 12, there are usually micro scratches of 1 μm or less or mechanical damages 13 of minute holes generated by mirror finishing.
(H) The seven active wafers 11 have intermediate oxide films 15 (SiO2) having different thicknesses of seven levels on the wafer surface. ₂ Film) is grown by thermal oxidation.
[0025]
The thickness of the intermediate oxide film is the same as that of the example. (1) 0 mm, (2) 1000 mm, (3) 2000 mm, (4) 4000 mm, (5) 6000 mm, (6) 8000 mm, (7) 10,000 mm It was.
(I) The active wafer 11 is bonded to the support wafer 12 on the side subjected to the mirror-finished surface 11a.
(J) The surface of the active wafer 11 bonded to the support wafer 12 is thinned by machining etching, chemical etching, and vapor phase etching. Thus, a thin film SOI wafer 10 having an SOI layer thickness Ta of 1000 mm is finally produced.
(K) A 1000 Å thin-film SOI wafer 10 is immersed in a hydrogen fluoride solution, and is then SiO2 using a microscope. ₂ The number of pits (HF pits) was counted.
[0026]
As a result, as shown by the circles in FIG. 6, the HF pit density of the sample that was not subjected to the spin etching showed a high value in the intermediate oxide films (1) 0, (2) 1000, and (3) 2000. It was. This is because SiO that becomes the intermediate oxide film 15 is formed. ₂ However, if it is 4000 mm or less, the mechanical damage 13 remains in the intermediate oxide film 15 and the HF defect density is high. In the case of thermal oxidation, about half of the oxide film is generated on the wafer surface, and the other half is generated by penetrating into the bulk. Therefore, when the intermediate oxide film is 6000 mm or more, the damage caused by mirror finishing is taken into the oxide film and disappears, and no great difference is seen in the HF pit density regardless of the presence or absence of spin etching. However, the HF pit density is slightly higher than those of the samples that were not subjected to spin etching at 4000 mm and 8000 mm, because the mechanical damage 13 caused by mirror processing exists, and the thick intermediate oxide film 15 is formed. Even if applied, it shows that mechanical damage 13 may remain, and it seems that these lead to the generation of defective products.
[0027]
From the results of Example 1 and Comparative Example 1, the thickness of the intermediate oxide film layer is 6000 mm or less, and the effect of removing mechanical damage by spin etching is manifested. The effect of removing the mechanical damage is preferably 4000 mm or less. Turned out to be great.
[0028]
(Example 2)
In Example 2, a process of manufacturing a smart cut thin film SOI wafer using the present invention will be described with reference to FIG.
(L) Seven pairs of two semiconductor silicon wafers 21 and 22 having diameters of 150 mm (referred to as active wafer 21 and support wafer 22) were prepared, and the mirror surface processing was applied to the surfaces 21a and 22a. On the mirror-finished surfaces 21 a and 22 a of the semiconductor silicon wafers 21 and 22, microscratches usually having a size of 1 μm or less or mechanical damages 23 of minute small holes generated by the mirror-finishing are generated.
(M) The active wafer 21 is subjected to spin etching on the mirror-finished surface 21a to remove mechanical scratches 23 caused by the mirror-finishing or microscratches or minute holes. The machining allowance Gr of the mirror-finished surface 21a by spin etching was set to 5 μm as described above. As an etchant used for this spin etching, a mixed acid (hydrofluoric acid, nitric acid, sulfuric acid, phosphoric acid) having a high etching rate and uniform etching characteristics was used as described above. As a result, the flatness and microroughness of the spin-etched surface 21b of the active wafer 21 are processed uniformly over the entire surface of the wafer, so that the same accuracy as that of the mirror surface processing can be obtained and the adhesive strength can be kept good. .
(N) Seven levels of intermediate oxide films 27 (SiO 2) on the spin-etched surface 21b of the seven active wafers 21 and the surface 22a of the support wafer 22 ₂ Film) is grown by thermal oxidation.
[0029]
In the manufacture of smart cut thin film SOI wafers, it is necessary to inject hydrogen into the active wafer as will be described later. However, if there is an oxide film having a thickness as required for a normal SOI wafer, it serves as a shield against hydrogen injection. It works and the injection is hindered. Therefore, a method is adopted in which most of the required oxide film is formed on the support wafer, and only a very small amount is formed on the active wafer. Although it is ideal that there is no oxide film on the active wafer from the meaning of shielding, the energy at the time of implantation may in turn cause damage to the silicon part that will be the SOI layer in the future. The oxide film is applied to the active wafer very thinly to the extent that it does not hinder.
[0030]
The level of the thickness of the intermediate oxide film 27 is the sum of the oxide film formed on the active wafer and the oxide film formed on the support wafer. (1) 0, (2) 1000, (3) 2000, (4) 4000 kg, (5) 6000 kg, (6) 8000 kg, and (7) 10,000 kg.
(O) Hydrogen 29 is injected into the active wafer 21 to which the intermediate oxide film 27 has been applied to form a hydrogen injection layer 29a at a predetermined depth.
(P) The active wafer 21 that has been subjected to the spin etching is bonded to the support wafer 22 on the spin etching processed surface 21b side.
(Q) After the active wafer 21 is bonded to the support wafer 22, the active wafer 21 is subjected to an annealing process at 500 ° C. to 600 ° C. and divided by the hydrogen injection layer 29 a. The surface of the active wafer 21 bonded to the support wafer 22 is thinned by machining. In this way, a smart cut thin film SOI wafer 1B having an SOI layer thickness Ta of 1000 mm is manufactured.
[0031]
After the smart cut thin film SOI wafer 1B is immersed in a hydrogen fluoride solution, it is SiO using a microscope. ₂ The number of pits (HF pits) was counted.
The result of this smart cut thin film SOI wafer 1B is the same as in Example 1 of FIG. 6, and the HF pit density of the sample subjected to the spin etching as shown by the mark ● is SiO to be the intermediate oxide film 27. ₂ It was confirmed that a constant value was obtained regardless of the thickness of the film. Since the mechanical damage 23 is removed by spin etching as in the first embodiment, the HF pit density is constant and low at all levels. In addition, when spin etching is performed, there is no very shallow mechanical damage 23 in which no through defect is formed, and the device yield is improved.
[0032]
(Example 3)
In Example 3, a process of manufacturing a SIMOX wafer using the present invention will be described with reference to FIG.
(U) The surface 31a of the semiconductor silicon wafer 31 having a diameter of 150 mm was mirror-finished. On the surface 31a, a mechanical scratch 33 of a micro scratch of 1 μm or a small small hole usually generated by mirror finishing is generated. The semiconductor silicon wafer 31 was subjected to spin etching on the mirror-finished surface 31a to remove mechanical scratches 33 of micro scratches or minute holes generated by the mirror finishing. The machining allowance Gr of the mirror-finished surface 31a by spin etching was set to 5 μm as described above. As an etchant used for the spin etching, a mixed acid (hydrofluoric acid, nitric acid, sulfuric acid, phosphoric acid) having a high etching rate and uniform etching characteristics was used as described above.
(V) Oxygen ions 37 were implanted into a predetermined position in the wafer from the mirror-finished surface 31b subjected to spin etching with an ion implantation apparatus. After the implantation of oxygen ions 37, heat treatment was performed at 1100 to 1300 ° C. for several hours in an argon atmosphere to form an intermediate oxide film 39 at a predetermined depth to obtain a SIMOX wafer 30.
[0033]
After the SIMOX wafer 30 is immersed in a hydrogen fluoride solution, the SiOX wafer 30 is scanned using a microscope. ₂ The number of pits (HF pits) was counted. The thickness Ta of the SOI layer at this time is 1000 mm.
[0034]
As a result, a density equivalent to that of the HF pits of the sample subjected to spin etching corresponding to 0Å indicated by ● in FIG. 6 was obtained. This is presumably because, in the sample subjected to the spin etching, the mechanical damage 33, which is increased by the energy during implantation of the implanted oxygen ions 37, is removed by the spin etching.
[0035]
【The invention's effect】
As described above, according to the present invention, mechanical damage of micro scratches or minute holes due to mirror finishing is effectively removed. Also, the etched surface obtained by spin etching, unlike other alkali etching, etc., has very good flatness and good surface microroughness, so that the active wafer is bonded to the support wafer after spin etching. There is no adverse effect. Therefore, if the thin film wafer for semiconductor manufactured by this invention is used, the electrical property of a semiconductor device can be improved and a yield can be improved. In addition, by using a mixed acid (hydrofluoric acid, nitric acid, sulfuric acid, phosphoric acid) having a high etching rate and uniform etching characteristics as the etchant, the flatness and microroughness of the spin-etched surface are mirror-finished. It is possible to maintain the same accuracy as that, and the adhesive strength can also be kept good. Further, since the thickness of the intermediate oxide film layer is 6000 mm or less, the effect of removing mechanical damage by spin etching is exhibited, and the effect becomes remarkable at 4000 mm or less.
[Brief description of the drawings]
FIG. 1 is a flowchart of a method for manufacturing a bonded SOI wafer according to an embodiment.
FIG. 2 is an explanatory diagram of an etching action of spin etching.
FIG. 3 is an explanatory diagram of the etching action of immersion etching.
FIG. 4 is a flowchart of a method for manufacturing a SIMOX wafer according to the embodiment.
FIG. 5 is a manufacturing process diagram illustrating a method for manufacturing an SOI wafer according to an embodiment.
FIG. 6 is a diagram for explaining the relationship between the thickness of an intermediate oxide film and the density of HF pits with and without spin etching.
FIG. 7 is a manufacturing process diagram showing a conventional method for manufacturing an SOI wafer.
FIG. 8 is a manufacturing process diagram illustrating a manufacturing method of a smart cut SOI wafer according to an embodiment.
FIG. 9 is a manufacturing process diagram illustrating a method of manufacturing a SIMOX wafer according to an example.
FIG. 10 is a manufacturing process diagram showing a manufacturing method of a conventional smart cut SOI wafer.
FIG. 11 is a manufacturing process diagram showing a conventional method for manufacturing an SOI wafer.
[Explanation of symbols]
1, 11, 12, 21, 22 Semiconductor silicon wafer
1A, 10 Thin-film SOI wafer
3, 13, 23 Mechanical damage
7, 15, 27 Intermediate oxide film
29 Hydrogen
29a Hydrogen injection layer
30 SIMOX wafer
31 Semiconductor silicon wafer
37 oxygen ions
39 Intermediate oxide film (buried oxide layer B-SiO ₂ )

Claims (5)

In the method for manufacturing a semiconductor thin film wafer, the surface of the mirror-polished active wafer is oxidized and bonded to a support wafer, and the active wafer is thinned to manufacture a semiconductor wafer.
The active wafer is subjected to a process for removing mechanical damage generated by the mirror polishing process by spin etching on the mirror-polished surface of the active wafer, the mechanical damage removing process surface is oxidized and bonded to the support wafer, and then the active wafer A method for producing a thin film wafer for a semiconductor, comprising:   2. The method of manufacturing a thin film wafer for a semiconductor according to claim 1, wherein the machining allowance by the spin etching treatment is set to a depth equal to or greater than the mechanical damage due to the mirror polishing.   The method of manufacturing a thin film wafer for a semiconductor device according to claim 1, wherein the thinning process of the active wafer is performed by machining and etching.   3. The method of manufacturing a thin film wafer for a semiconductor according to claim 1, wherein the thinning process of the active wafer is performed by implanting hydrogen ions into the active wafer and dividing the active wafer by a hydrogen implanted layer. . In a method for manufacturing a thin film wafer for a semiconductor in which oxygen ions are implanted into a mirror-polished wafer to form a buried oxide film,
A method for manufacturing a thin film wafer for a semiconductor, in which a mirror-polished surface is subjected to a process for removing mechanical damage caused by the mirror-polishing process by spin etching , and then oxygen ions are implanted to form a buried oxide film.

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