JP2007220886A - Semiconductor film manufacturing method, and electronic component manufacturing method using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor film manufacturing method excellent in productivity while enabling wide range selection of materials. <P>SOLUTION: The method for manufacturing a semiconductor film 3 includes a step for forming a conductor layer 2 in a partial region on the surface of a film growth substrate 1, a step for forming the semiconductor film 3 covering the conductor layer 2 by epitaxially growing a semiconductor from a region other than the partial region on the surface of the film growth substrate 1, and a step for separating the semiconductor film 3 from the film growth substrate 1 by heating the conductor layer 2 by electromagnetic induction with an induction heating coil 4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a semiconductor film using epitaxial growth and a method for manufacturing an electronic component using the same.

  A semiconductor film can be formed by epitaxially growing a semiconductor on the surface of the substrate, and an electronic component including the semiconductor film can be manufactured by using such a semiconductor film formation. A substrate used for forming a semiconductor film by epitaxial growth as described above is hereinafter referred to as a film growth substrate.

  The semiconductor film formed on the surface of the film formation substrate as described above may be used separately from the film formation substrate to constitute an electronic component. As a method for separating a semiconductor film from a film formation substrate, removal by physical etching such as chemical etching or polishing (hereinafter, these chemical etching and physical etching are collectively referred to simply as “etching”) is used. . In these methods, the removal of the film-forming substrate proceeds slowly, the use of corrosive chemicals is required, and the film-growing substrate cannot be repeatedly used (reused).

  As a film forming substrate, semiconductors such as indium nitride (InN), gallium nitride (GaN), and aluminum nitride (AlN), and mixed crystals or alloys thereof (hereinafter collectively referred to as “group III element nitrides”) May be used. This group III element nitride is extremely difficult to chemically etch and does not provide a reliable wet chemical etching method and must be processed by a reactive ion etching (dry etching) method . However, this method is very expensive industrially and has a drawback that the etching rate is relatively slow and a toxic gas (for example, boron trichloride) is required. In addition, these etching methods require precise control of the etching rate and etching time in order to achieve a desired etching depth.

Incidentally, in Japanese Patent Laid-Open No. 5-299362 (Patent Document 1), in a semiconductor element wafer having an epitaxial operation layer on a growth substrate, a buffer made of a layered compound having an excellent cleavage property between the growth substrate and the operation layer. Those with layers are described. Patent Document 1 discloses a method of manufacturing a semiconductor element having an epitaxial operation layer using this semiconductor element wafer. Here, a buffer layer made of a layered compound having an excellent cleavage property is formed on the growth substrate, and after the operation layer is epitaxially grown on the buffer layer, the operation layer and the growth substrate are peeled off to form a support substrate for a semiconductor element. It is joined. In another method, a buffer layer made of a layered compound having an excellent cleavage property is formed on the growth substrate, and at least a part of the buffer layer other than the element formation region is removed to expose the growth substrate. An operating layer is epitaxially grown on the exposed portion of the semiconductor layer and the buffer layer. Thereafter, only the element formation region is cut out and taken out, and the operation layer in the element region is peeled off from the growth substrate and bonded to the support substrate for the semiconductor element. According to the method described in Patent Document 1, some of the technical problems associated with etching are solved.
Japanese Patent Laid-Open No. 5-299362

By the way, in the method described in Patent Document 1, it is preferable that the layered compound having excellent cleaving property used as the buffer layer is preferably one that bonds the layers with van der Waals force (molecular bonding force). ing. As such a layered compound having excellent cleavage properties, specifically, MoS ₂ , NbS ₂ , MoSe ₂ , NbSe ₂ , GaSe, SnS ₂ , SnSe ₂ , and InSe are disclosed. Thus, the method described in Patent Document 1 requires the use of a very limited buffer layer. Further, in the method described in Patent Document 1, it takes considerable time to sufficiently remove the buffer layer from the operation layer.

  An object of the present invention is to provide a method for manufacturing a semiconductor film, which allows a wide selection of materials and has excellent productivity. Moreover, the objective of this invention is providing the method of manufacturing an electronic component using the manufacturing method of such a semiconductor film.

  According to a first aspect of the present invention, there is provided a semiconductor film manufacturing method including the following steps to achieve the above object. That is, in the first step, a conductor layer is formed in a partial region of the surface of the film growth substrate. In the second step, a semiconductor is epitaxially grown from a region other than the partial region on the surface of the film growth substrate to form a semiconductor film covering the conductor layer. In the third step, the semiconductor layer is separated from the film growth substrate by heating the conductor layer by electromagnetic induction.

  Moreover, according to the 2nd thing of this invention, in order to achieve said objective, the manufacturing method of the semiconductor film characterized by including the following process is provided. That is, in the first step, a conductor layer is formed on the surface of the first substrate. In the second step, the first surface of the second substrate as the film growth substrate is bonded to the surface of the conductor layer. In the third step, a semiconductor film is formed by epitaxially growing a semiconductor on the second surface opposite to the first surface of the second substrate. In the fourth step, the second substrate is separated from the first substrate by causing the conductor layer to generate heat by electromagnetic induction.

  In the method of the present invention as described above, the semiconductor layer is separated from the film growth substrate by heating the conductor layer by electromagnetic induction, or the second substrate on which the semiconductor film is formed is the first substrate. Separate from. Therefore, a wide variety of materials can be selected for the film growth substrate or the second substrate, the conductor layer, the semiconductor film, or the first substrate, and the productivity is excellent.

  The first aspect of the present invention includes the following embodiments.

  That is, a dielectric layer or a semiconductor layer is formed on the conductor layer in the step of forming the conductor layer.

  A plurality of patterned conductor layers are repeatedly arranged, and the arrangement pitch of the conductor layers is such that the central portion between adjacent conductor layers is heated by heating the conductor layers by the electromagnetic induction. The temperature is set to be higher than the first order phase transition temperature.

  A plurality of patterned conductor layers are repeatedly arranged, and the conductor layers are arranged by causing the conductor layers to generate heat by the electromagnetic induction so that the central portion between adjacent conductor layers is The temperature is set to be higher than the first order phase transition temperature.

  The film growth substrate is disposed so as to be perpendicular to the direction of the lines of magnetic force generated by the electromagnetic induction.

  The conductor layer is made of a material that adsorbs nitrogen.

  By heating the conductor layer, the film growth substrate and / or the semiconductor film are heated to the first phase transition temperature or higher of these materials. Melting, sublimation or decomposition of the material for the film growth substrate and / or the material for the semiconductor film at the interface between them and / or the interface between the semiconductor film and the conductor layer, and the substrate for film growth And the semiconductor film are separated from each other.

  By heating the conductor layer, the film growth substrate and / or the semiconductor film are heated to less than the primary phase transition temperature of these materials. Stress is generated in the film growth substrate and / or the semiconductor film at the interface between them and / or the interface between the semiconductor film and the conductor layer, so that the film growth substrate and the semiconductor film are separated from each other. Let

  The semiconductor is a group III element nitride semiconductor that decomposes into a compound containing a group III element and nitrogen by heating at or above the primary phase transition temperature.

  The second aspect of the present invention includes the following embodiments.

  That is, by heating the conductor layer, the second substrate is heated to a temperature higher than the first phase transition temperature of the material, and the material of the second substrate is melted on the first surface of the second substrate. Then, sublimation or decomposition is caused to separate the second substrate and the conductor layer from each other.

  Heating the conductive layer to heat the second substrate to less than the first phase transition temperature of the material, generating stress on the second substrate at the first surface, The conductor layers are separated from each other.

  Further, the first and second embodiments of the present invention have the following embodiments.

  That is, the film growth substrate or the second substrate is a group III element nitride semiconductor that decomposes into a compound containing a group III element and nitrogen by heating at or above the primary phase transition temperature.

  The semiconductor film and the film growth substrate or the second substrate are compound semiconductors made of the same element.

  The conductor layer is made of a magnetic material.

  In the step of separating the semiconductor film from the film growth substrate or the step of separating the second substrate from the first substrate, the following is performed. That is, before the conductive layer is heated by electromagnetic induction, the film growth substrate or the second substrate, the conductive layer, and the semiconductor film or the first substrate have their primary phase transition temperatures. Preheat to the following.

  In addition, according to the present invention, the semiconductor film is manufactured by the method for manufacturing a semiconductor film as described above, and another member is added to the semiconductor film obtained thereby, Is provided.

  Embodiments of a method for manufacturing a semiconductor film and a method for manufacturing an electronic component using the same according to the present invention will be described below with reference to the drawings. However, the present invention is not limited to the following embodiments.

<Embodiment 1>
In FIG. 1, the schematic of the process of this embodiment is shown.

  First, as shown in FIG. 1A, the conductor layer 2 is formed in a partial region of the surface of the film growth substrate 1. As the substrate 1, an insulating substrate such as a sapphire substrate or a SiC substrate can be used. Examples of the size of the substrate 1 are about 1 cm in length and width. The conductor layer 2 is formed in an appropriate pattern on the surface of the substrate 1. As this pattern, for example, a line or stripe pattern extending in a direction perpendicular to the paper surface in FIG. 1 is exemplified. As for the dimension of the conductor layer 2 having a line pattern, for example, a width of about 10 μm and a thickness of 1 μm are exemplified. A plurality of patterned conductor layers 2 are repeatedly arranged, and the plurality of conductor layers 2 are arranged in parallel to each other. The pitch of the arrangement is, for example, about 20 μm. The thickness of the conductor layer 2 is, for example, 1 μm. An example of the material of the conductor layer 2 is graphite carbon, which can be formed by vapor deposition or epitaxial growth.

  Next, a semiconductor is epitaxially grown from a region other than the region where the conductor layer 2 is formed on the surface of the film growth substrate 1 to form a semiconductor film 3 covering the conductor layer 2. Examples of the semiconductor include group III element nitrides such as gallium nitride, indium nitride and aluminum nitride, other group III-V compound semiconductors, and other compound semiconductors. In such selective epitaxial growth, it is known that the patterned conductor layer 2 can be covered with an epitaxial film by lateral growth accompanying an increase in the thickness of the epitaxial film. That is, in selective growth, a facet structure that appears because the growth rate is slower than the other surfaces appears, dislocations progress toward the facets, and dislocations that have been extended perpendicular to the substrate 1 can extend in the vertical direction. It is thought to be lost. Thereby, the crystal growth of the III-V group compound semiconductor with few crystal defects such as gallium nitride can be performed on the conductor layer 2 as well.

  Next, as shown in FIG. 1B, the semiconductor layer 3 is made to be a substrate for film growth 1 and a conductor layer by causing the conductor layer 2 to generate heat by electromagnetic induction using the induction heating coil 4. Separate from 2. That is, by causing a high-frequency current to flow through the induction heating coil 4, the conductor layer 2 can be heated to a high temperature of 1000 ° C. or higher by heat generation due to eddy current loss or hysteresis loss in electromagnetic induction. Due to this heat generation, the film growth substrate 1 and / or the semiconductor film 3 is heated below the first-order phase transition temperature of these materials. As a result, portions of the film growth substrate 1 and the semiconductor film 3 in the vicinity of the conductor layer 2, particularly the vicinity of the interface between the semiconductor film 3 and the film growth substrate 1 and the vicinity of the interface between the conductor layer 2 and the semiconductor film 3 are heated. Is done. The semiconductor film 3 is separated from the film growth substrate 1 and the conductor layer 2 by thermal stress based on this. FIG. 1C shows a state where the semiconductor film 3 is separated from the film growth substrate 1 and the conductor layer 2.

  In this embodiment, a 1 cm square sapphire substrate is used as the substrate 1 for compound semiconductor film growth, and a graphite carbon layer as a conductor layer 2 for substrate separation is formed on the surface by vapor deposition. A number of graphite carbon layers were arranged at a pitch of 20 μm in a line pattern of width 10 μm × length 1 cm × thickness 1 μm (line 10 μm + space 10 μm, electrode volume V = 1 cm × 1/2 × 1 cm × 1 μm). Further, gallium nitride was epitaxially grown thereon to form a gallium nitride film 3.

  Next, electromagnetic induction was performed under the following conditions to separate the gallium nitride film 3 from the sapphire substrate 1 and the graphite carbon layer 2.

The amount of heat required for heating graphite having a volume V = 1 cm × 1/2 × 1 cm × 1 μm = 1/2 × 10 ⁻⁴ cm ³ to room temperature + 1200 ° C. is Q = MCΔT (where Q [J], The weight of the object to be heated is M [g]). Here, if the density d = 1.85, the specific heat C = 0.65 [J / g · K], and the rising temperature ΔT = 1200 [° C.], Q = 1.85 × 1/2 × 10 ⁻⁴ × 0.65 × 1200 = 0.07215 [ J]. If the heating time is 1μs, the required power is P = 0.07215 / 10 ⁻⁶ = 7.215 [kW].

Here, it is assumed that the graphite resistivity is ρ ₀ = 800 [μΩ · cm] and the graphite relative permeability is μ _r = 1. In this case, the relationship between the penetration depth p [mm] of the electromagnetic wave and the frequency f is f = 1 (50.3 / 1 × 10 ⁻³ ) ² × 1/800 = 3.16, where p = 1 μm = 1 × 10 ⁻³ mm. [M Hz]. Therefore, if it is 3 MHz or less, the graphite carbon layer 2 having a thickness of 1 μm can be heated uniformly.

  Therefore, in this embodiment, induction heating was performed for 10 μsec with an output of 8 kW at an AC frequency of 3 kHz.

  An electronic component can be manufactured using the semiconductor film 3 such as a gallium nitride film obtained as described above. For example, as shown in FIG. 2, the semiconductor film 3 is bonded to a suitable device substrate 20, and an electrode 21 and an insulating layer 22 are formed as necessary. An electronic circuit connected to the semiconductor film 3 can be built in the device substrate 20 in advance. It is also possible to add another semiconductor film in addition to the semiconductor film 3. Examples of the electronic component thus obtained include a light emitting element and a light receiving element.

<Embodiment 2>
In the present embodiment, in the step of forming the conductor layer 2 in the first embodiment, a dielectric layer (or semiconductor layer) 5 is further formed on the conductor layer 2 as shown in FIG. This dielectric layer 5 is formed in order to prevent the conductor layer 2 from hindering when the compound semiconductor is epitaxially grown. That is, since the optimum conditions for selective epitaxial growth differ depending on the material of the conductor layer 2, only the surface of the patterned conductor layer 2 is covered with the dielectric layer (or semiconductor layer) 5 so as to approach this optimum condition. As a material of the dielectric layer 5, SiO ₂ or the like can be used. By covering the dielectric layer 5, selective epitaxial growth with a dielectric or semiconductor having the same or similar structure as the film growth substrate 1 can be performed without depending on the material of the conductor layer 2.

In the present embodiment, the SiO ₂ layer 5 having the same shape pattern is formed to a thickness of 1000 mm on the conductor layer 2 made of graphite carbon having the same linear pattern as that used in the first embodiment. The formation of the coating of the dielectric layer 5 has substantially no influence on the separation between the film growth substrate 1 and the compound semiconductor film 3. It is known that a dielectric also generates heat by electromagnetic induction, but compared with a conductor, the amount of heat generated by the dielectric and the shield loss are negligible. Further, since the dielectric layer is thin, heat can be propagated without any problem.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Embodiment 3>
In the present embodiment, when the conductor layer 2 generates heat, the film growth substrate 1 and / or the semiconductor film 3 is heated to a temperature higher than the primary phase transition temperature of these materials. Accordingly, the film growth substrate 1 and the semiconductor film 3 in the vicinity of the conductor layer 2, particularly in the vicinity of the interface between the semiconductor film 3 and the film growth substrate 1 and in the vicinity of the interface between the conductor layer 2 and the semiconductor film 3. The material of the film growth substrate 1 and / or the material of the semiconductor film 3 is melted, sublimated or decomposed. Thus, the semiconductor film 3 is separated from the film growth substrate 1 and the conductor layer 2.

  In the present embodiment, a patterned conductor layer 2 made of graphite carbon is formed on the sapphire substrate 1 in the same manner as in the first embodiment, and the semiconductor film 3 made of GaAs is epitaxially grown. It is known that the melting point of GaAs is 1238 ° C. When electromagnetic induction heating was performed under conditions of 10 milliseconds with an output of 15 kW at an AC frequency of 3 kHz, the vicinity of the interface between the conductor layer 2 of the GaAs film 3 and the film growth substrate 1 was once melted. For this reason, stress concentrates on the interface between the sapphire substrate 1 and the conductor layer 2 and the GaAs film 3 which have been returned to room temperature, and thus the GaAs film 3 is easily separated from the sapphire substrate 1 and the conductor layer 2.

  In this embodiment, since the separation is based on the phase transition of the compound semiconductor, the processing accuracy of the separation surface can be increased as compared with the separation based on the thermal stress strain. In particular, when the substrate 1 or the compound semiconductor film 3 is made of a nitride, an irreversible reaction occurs due to induction heating, so that separation can be performed more reliably.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Embodiment 4>
In the present embodiment, the semiconductor film 3 is a group III element nitride semiconductor that decomposes into a compound containing a group III element and nitrogen by heating at or above the primary phase transition temperature.

In the present embodiment, a substrate obtained by growing aluminum nitride at a low temperature on the surface of a 1 cm square sapphire substrate is used as the film growth substrate 1. The conductor layer 2 was made of tungsten and formed in a line pattern having a width of 10 μm × thickness 1 μm × length 1 cm, and the patterns were arranged in parallel at a pitch of 20 μm. Epitaxial growth of group III element nitride semiconductor aluminum gallium nitride (composition formula: Al _0.2 Ga _0.8 N) was performed to form a semiconductor film 3.

The substrate 1 for film growth, the patterned conductor layer 2 and the compound semiconductor film 3 formed by epitaxial growth were heated by electromagnetic induction for 10 μsec with an output of 15 kW at an AC frequency of 3 kHz. Since the temperature of the melting point of Al _0.2 Ga _0.8 N has been reached, a compound containing a group III element in the vicinity of the interface between the conductor layer 2 and the film growth substrate 1 of the compound semiconductor film 3 formed by epitaxial growth (group III element) In itself) and nitrogen. As a result, separation occurred at the interface between the Al _0.2 Ga _0.8 N compound semiconductor film 3 and the film growth substrate 1 having the aluminum nitride surface and the conductor layer 2. The melting point of the aluminum nitride single crystal is about 2400 ° C. to 3273 ° C., although there is a difference depending on the document described. The melting point of Al _0.2 Ga _0.8 N is in the range of 1200 ° C to 1500 ° C. In any case, there is a difference of about 1000 ° C. between the melting point of aluminum nitride of the film growth substrate 1 and the melting point of the epitaxially grown Al _0.2 Ga _0.8 N film 3.

  Therefore, in this embodiment, the film growth substrate 1 can be separated from the substrate 1 under the condition that the film growth substrate 1 is not decomposed and the epitaxial growth compound semiconductor film 3 is decomposed. Easy to (reuse).

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Embodiment 5>
In this embodiment, the film growth substrate 1 is a group III element nitride semiconductor that decomposes into a compound containing a group III element and nitrogen by heating at or above the primary phase transition temperature.

In this embodiment, gallium nitride manufactured by Sumitomo Electric Industries, Ltd. cut into a 1 cm square is used as the film growth substrate 1. The conductor layer 2 was made of tungsten and formed in a line pattern having a width of 10 μm × thickness 1 μm × length 1 cm, and the patterns were arranged in parallel at a pitch of 20 μm. Epitaxial growth of group III element nitride semiconductor aluminum gallium nitride (composition formula: Al _0.2 Ga _0.8 N) was performed to form a semiconductor film 3.

The film growth substrate 1, the patterned conductor layer 2, and the compound semiconductor film 3 formed by epitaxial growth were heated by electromagnetic induction for 10 milliseconds with an output of 15 kW at an AC frequency of 3 kHz. The melting point of the gallium nitride substrate 1 reached 1200 ° C. and Al _0.2 Ga _0.8 N or higher. For this reason, the interface between the film growth substrate 1 and the compound semiconductor film 3 and the vicinity of the interface between the compound semiconductor film 3 and the film growth substrate 1 and the conductor layer 2 are decomposed into a compound containing a group III element and nitrogen. . As a result, separation occurred at the interface between the Al _0.2 Ga _0.8 N compound semiconductor film 3 and the gallium nitride substrate 1 and the conductor layer 2.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Embodiment 6>
In the present embodiment, the semiconductor film 3 and the film growth substrate 1 are compound semiconductors made of the same element.

  In the present embodiment, a 1 cm square gallium nitride substrate is used as the film growth substrate. The conductor layer 2 was made of tungsten and formed in a line pattern having a width of 10 μm × thickness 1 μm × length 1 cm, and the patterns were arranged in parallel at a pitch of 20 μm. The semiconductor film 3 was formed by epitaxial growth of gallium nitride.

  The film growth substrate 1, the patterned conductor layer 2, and the compound semiconductor film 3 formed by epitaxial growth were heated by electromagnetic induction for 10 milliseconds with an output of 15 kW at an AC frequency of 3 kHz. Since the melting point of the gallium nitride substrate 1 and the gallium nitride film 3 reached a temperature of 1200 ° C. or more, the film growth substrate 1 and the gallium nitride film 3 were decomposed into a compound containing a group III element and nitrogen. As a result, separation occurred at the interface between the gallium nitride film 3 and the gallium nitride substrate 1 and the conductor layer 2.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Embodiment 7>
In the present embodiment, the conductor layer 2 is made of a magnetic material.

  In the present embodiment, a 1 cm square gallium nitride substrate is used as the film growth substrate. The conductor layer 2 is made of fcc cobalt, which is a magnetic material, and is formed in a line pattern having a width of 10 μm, a thickness of 1 μm, and a length of 1 cm, and the patterns are arranged in parallel at a pitch of 20 μm. The semiconductor film 3 was formed by epitaxial growth of indium phosphide.

  The film growth substrate 1, the patterned conductor layer 2, and the compound semiconductor film 3 formed by epitaxial growth were heated by electromagnetic induction for 10 milliseconds with an AC frequency of 30 kHz and an output of 15 kW. Separation occurred at the interface between the indium phosphide film 3 and the gallium nitride substrate 1 and the conductor layer 2 due to the stress concentration when the melting point of indium phosphide reached 1070 ° C. and then returned to room temperature.

  The Curie point temperature of fcc cobalt is 1115 ° C., which is higher than the melting point of indium phosphide. However, since the melting point of gallium nitride of the film growth substrate 1 is 1200 ° C. or less, the decomposition and damage of the film growth substrate 1 are suppressed, and its reuse becomes easy.

  Thus, when the material of the conductor layer 2 is a magnetic material, the Curie point temperature can be controlled by the composition.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Eighth embodiment>
In the present embodiment, the arrangement pitch of the conductor layers 2 is set so that the central portion between adjacent conductor layers has a temperature equal to or higher than the primary phase transition temperature by causing the conductor layers 2 to generate heat by electromagnetic induction. Has been.

Take an example. In-plane direction lines of a one-dimensional line & space comprising a plurality of parallel line-shaped pattern portions (corresponding to the conductor layer 2) made of a conductive material and non-conductive portions between adjacent line-shaped pattern portions; Let x be the coordinates in the orthogonal direction. Further, the thermal diffusivity of the non-conductive portion is a = 1 (the thermal conductivity K = cρ where c is the specific heat of the non-conductive portion and ρ is the density). Here, equation of heat conduction (∂θ / ∂t) = [K / (cρ)] (∂ 2 θ / ∂x 2) = solving ^{a (∂ 2 θ / ∂x 2} ). As a result, the temperature of the central portion of the space (corresponding to the central portion between adjacent conductor layers) in an infinite time when the heating element having the initial temperature T ₀ is present in a one-dimensional line shape is obtained as follows. That is, when the line / space ratio (conductive material pattern portion / non-conductive portion) is 11/9 and 11/29, 0.543T ₀ and 0.244T ₀ are obtained, respectively. The conductive material pattern portion referred to here corresponds to the conductor layer of the present invention, and the non-conductive portion is the film growth substrate or semiconductor film of the present invention and fills the space between the conductive material pattern portions. It corresponds to a thing.

  In the present embodiment, when the compound semiconductor film 3 made of gallium nitride having a melting point of the primary phase transition temperature of 1200 ° C. is used, the conductor layer 2 may be made of tungsten. In this case, the condition for the temperature of the central portion of the space of conductive material pattern portion / nonconductive portion = 11/9 to be 1200 ° C. is that the initial temperature of the conductive pattern portion is 2210 ° C. or higher. This condition can be satisfactorily satisfied in this embodiment because the melting point of tungsten is 3410 ° C.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Ninth Embodiment>
In this embodiment, the arrangement of the conductor layers 2 is set so that the central portion between adjacent conductor layers has a temperature equal to or higher than the primary phase transition temperature by causing the conductor layers 2 to generate heat by electromagnetic induction. ing.

  Also for the pattern in which the line and space pattern shown in the eighth embodiment is expanded two-dimensionally, the temperature of the central portion of the non-conductive portion between the patterns becomes equal to or higher than the first-order phase transition temperature by solving the same heat conduction equation. Can be designed as

  Take an example. As a method for two-dimensionally arranging the conductor layers 2 in a dotted pattern, a square lattice arrangement in which the arrangement pitches in the vertical and horizontal directions as shown in FIG. 4 (a) are set as shown in FIG. 4 (b). Such an equilateral triangular lattice arrangement in which the arrangement pitch in each of the three directions is a is compared. The center of gravity G1 of the non-conductive portion in the square unit region formed by the four conductive layers 2 that are vertically and horizontally adjacent to each other in the square lattice arrangement is a distance a / √ ( 2) separated by a distance. On the other hand, the gravity center G2 of the non-conductive portion in the unit area of the equilateral triangle formed by the three conductor layers 2 adjacent to each other in the three directions in the equilateral triangle lattice arrangement is the three conductors closest to it. Separated from the layer by a distance a / √ (3).

  As in this example, the heat conduction distance varies depending on the arrangement of the conductive material pattern portions. However, if the temperature at the center of gravity of the non-conductive portion is equal to or higher than the primary phase transition temperature, it is considered that the entire non-conductive portion is equal to or higher than the primary phase transition temperature. 3 and uniform and complete separation.

  If the above boundary condition is included in the heat conduction equation similar to that of the eighth embodiment, if the heat generation temperature of the conductive material pattern portion is the same, the temperature of the non-conductive portion is higher in the equilateral triangle lattice arrangement than in the square lattice arrangement described above. It turns out that becomes high.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Embodiment 10>
In the present embodiment, the film growth substrate 1 and the conductor layer 2 are arranged so as to be perpendicular to the direction of the lines of magnetic force generated by electromagnetic induction.

  Since the pattern of the conductor layer 2 has anisotropy, the amount of generated eddy current and the heat generation efficiency vary depending on the direction of the magnetic field generated by the induction heating coil 4 (direction of the lines of magnetic force). For this reason, there exists an optimal layout regarding arrangement | positioning of an electroconductive material pattern part, and this embodiment prescribes | regulates the optimal layout of the conductor layer 2. FIG.

  An example of induction heating by a general coil will be described with reference to FIG. The eddy current flows in the opposite direction with respect to the coil current that makes one round. In the case of the line & space conductive material pattern portion as in the eighth embodiment, the line direction is the x direction, the direction perpendicular to the line in the pattern plane is the y direction, and the thickness direction of the line is the z direction. Only heat generation by induction is considered without considering heat conduction in the material pattern part. In order to concentrate heat on the interface where the film growth substrate 1 and the epitaxially grown compound semiconductor film 3 are in contact with each other, it is considered that a high temperature of the pattern cross section (xy plane and yz plane) is an ideal heat generation state. In the present embodiment, as shown in FIG. 5A, the film growth substrate 1 and the conductor layer 2 are arranged so as to be perpendicular or substantially perpendicular to the direction of the magnetic force lines B generated by electromagnetic induction. To do. As a result, an eddy current flows in the xy plane, and the temperature around the xy plane, that is, the pattern cross section becomes the highest temperature, and the temperature distribution is most uniform. On the other hand, if an eddy current flows in the xz plane, no current flows in the pattern cross section (xz plane) in the x direction. Therefore, the film growth substrate 1 and the epitaxially grown compound semiconductor film 3 are in contact with each other. The efficiency of raising the temperature of the interface is low. Further, as shown in FIG. 5B, if the direction of the magnetic lines of force B generated by electromagnetic induction is set to the line direction and an eddy current flows in the yz plane, the pattern cross section in the x direction ( Efficiency is good because current flows in the xz plane). However, non-uniform temperature distribution is likely to occur due to non-uniform line width and film thickness.

  Therefore, in the case of the conductive material pattern portion of the line and space as in the eighth embodiment, the layout in which eddy current flows in the xy plane is ideal. The same applies to a conductive material pattern such as a square, and a layout in which the interface where the film growth substrate 1 and the epitaxially grown compound semiconductor film 3 are in contact with the coil loop is in the same plane is preferable. is there.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Embodiment 11>
In the present embodiment, the conductor layer 2 is made of a material (substance) that adsorbs nitrogen.

  When the film growth substrate 1 and / or the compound semiconductor film 3 formed by epitaxial growth is a group III element nitride, these are decomposed into a group III element compound (including a group III element metal) and nitrogen gas by induction heating. There are things to do. In this case, it is desirable to relieve the stress caused by the nitrogen gas and perform uniform separation between the compound semiconductor film 3 and the film growth substrate 1 and the conductor layer 2. Therefore, the conductor layer 2 can be made of a conductive material that adsorbs nitrogen gas generated by induction heating. As a conductive material that adsorbs nitrogen gas, graphite, particularly porous bodies such as carbon nanotubes and C60 are known. In the present embodiment, by using these as the material of the conductor layer 2, it can act as a heating element in induction heating, and can also play a role of adsorbing nitrogen gas generated by heating.

  In the present embodiment, a 1 cm square sapphire substrate is used as the compound semiconductor film growth substrate 1, and graphite carbon is formed to a thickness of 1 μm on the surface by arc discharge of a carbon electrode to form a conductor layer 2. did. Furthermore, epitaxial growth of gallium nitride as a compound semiconductor was performed thereon. Thereafter, induction heating was performed under the same conditions as in the first embodiment. The peeled surface of the gallium nitride film 3 was several percent flatter than that of the first embodiment. Therefore, the polishing process in the subsequent device fabrication stage was easy.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Twelfth embodiment>
In this embodiment, in the step of separating the semiconductor film 3 from the film growth substrate 1 and the conductor layer 2, before the conductor layer 2 generates heat by electromagnetic induction, the film growth substrate 1, the conductor layer 2, and the semiconductor The membranes 3 are preheated below their first order phase transition temperature.

  Since the heat generated by induction heating is additive, if the preheating is performed, the time and power required for induction heating can be adjusted and shortened. Furthermore, the substrate surface roughness after peeling can be improved.

  In this embodiment, a sapphire substrate having a size of 1 cm square was used as the compound semiconductor film growth substrate 1 in the same manner as in Embodiment 1, and graphite carbon was epitaxially grown on the surface thereof. As a result, a conductor layer 2 having a thickness of 1 μm, a line of 10 μm + a space of 10 μm, and a volume V = 1 cm × 1/2 × 1 cm × 1 μm was formed. Further, gallium nitride as a compound semiconductor was epitaxially grown thereon to form a semiconductor film 3. In a state where the whole was placed in an oven at 600 ° C., electromagnetic induction was performed under the following conditions to separate the gallium nitride film from the sapphire substrate and the conductor layer 2.

Graphite C having a volume V = 1 cm × 1/2 × 1 cm × 1 μm = 1/2 × 10 ⁻⁴ cm ³ is heated from 600 ° C. to 1200 ° C. (temperature difference ΔT = 600 ° C.). The amount of heat required in this case is Q = MCΔT (where Q [J], the weight of an object to be heated M [g]). The density d = 1.85, the specific heat C = 0.65 [J / g · K], and the temperature rise ΔT = 600 [° C.]. In this case, Q = 1/2 × 1.85 × 10 ⁻⁴ × 0.65 × 600 = 0.0361 [J]. If heating time is 1μs, P = 0.0361 / 10 ⁻⁶ = 3.61 [kW]. In addition, when comparing room temperature with 600 ° C preheating, the temperature difference from the portion heated to 1200 ° C is smaller when preheating is performed, so there is less damage due to the difference in thermal expansion, and as a result the substrate surface roughness after peeling I was able to improve.

  Using the semiconductor film 3 obtained in the present embodiment, an electronic component can be manufactured in the same manner as in the first embodiment.

<Embodiment 13>
FIG. 6 shows a schematic diagram of the steps of the present embodiment.

  First, as shown in FIG. 6A, the conductor layer 6 is uniformly formed on the surface of the first substrate 7. As the first substrate 7, a silicon substrate, a sapphire substrate, or a SiC substrate can be used. As a material of the conductor layer 6, copper can be used. The thickness of the conductor layer 6 is, for example, 1 μm.

  Next, the first surface (lower surface in the drawing) of the second substrate 8 is bonded to the surface (upper surface in the drawing) of the conductor layer 6. As the second substrate 8, a substrate made of a group III element nitride such as gallium nitride, indium nitride, or aluminum nitride, another group III-V compound semiconductor, or another compound semiconductor can be used. The thickness of the second substrate 8 is, for example, 2 μm, and this second substrate 8 can be supported by the support layer 9 for convenience of handling when bonded to the conductor layer 6. Examples of the material of the support layer 9 include chrome. The conductor layer 6 and the second substrate 8 can be joined by, for example, pressure bonding.

  Next, as shown in FIG. 6B, the support layer 9 is removed by, for example, etching to expose the second surface (the upper surface in the drawing) of the second substrate 8, and the The second surface is smoothed by polishing.

  Next, as shown in FIG. 6C, a semiconductor film 10 is formed by epitaxially growing a compound semiconductor, for example, AlxGa1-xN on the second surface (upper surface in the drawing) of the second substrate 8. The semiconductor film 10 constitutes a cladding layer of a semiconductor laser. A DBR structure is formed in the semiconductor film 10. Next, a compound semiconductor such as an InGaN-based semiconductor is deposited on the semiconductor film 10 to form the semiconductor film 11. The semiconductor film 11 constitutes an active layer of a semiconductor laser. Next, a compound semiconductor, for example, AlxGa1-xN is epitaxially grown on the semiconductor film 11 to form the semiconductor film 12. The semiconductor film 12 constitutes a cladding layer of a semiconductor laser. A DBR structure is formed in the semiconductor film 12.

  Next, as shown in FIG. 6D, as in the first embodiment, the conductor layer 6 is heated by electromagnetic induction using an induction heating coil. Thereby, the stacked body of the second substrate 8, the semiconductor film 10, the semiconductor film 11, and the semiconductor film 12 is separated from the first substrate 7 and the conductor layer 6.

  This embodiment is particularly effective when the second substrate 8 which is a semiconductor film growth substrate is thin. This is because when the second substrate 8 is bonded to the conductor layer 6, the second surface of the second substrate 8 is reinforced by attaching a support layer 9 to the second surface of the second substrate 8. This is because the support layer 9 can be removed before the semiconductor film 10 is epitaxially grown.

In this embodiment, the copper layer as the conductor layer 6 is uniformly formed with a thickness of 1 μm on the silicon substrate 7 as the first substrate. The 2 μm-thick GaN film 8 supported by the chromium metal layer as the support layer 9 is used as the second substrate for the growth of the semiconductor film, and the copper layer 6 and the GaN film at a temperature of 200 to 300 ° C. and a pressure of 42 kg / cm ^2. 8 was joined. After this bonding, the chromium metal layer 9 was removed, the exposed surface of the GaN film 8 was polished, and an AlxGa1-xN film 10 was grown thereon to form a DBR structure. Furthermore, after forming an active layer made of InGaN-based semiconductor film 11, an AlxGa1-xN film 12 was grown again to form a DBR structure.

  Next, induction heating similar to that of Embodiment 1 was performed to heat the copper layer, and the GaN film 8 was heated to a temperature of the melting point of 1200 ° C. or less, and the silicon substrate 7 and the copper layer 6 were separated and removed by stress. Thereby, an optically pumped laser device (semiconductor laser) having a III-V group compound semiconductor composition was obtained.

  In this embodiment, a semiconductor film 11 and a semiconductor film 12 are formed on a semiconductor film 10 to manufacture an electronic component. If these three films are regarded as semiconductor films in the present invention, the semiconductor film is manufactured. Also applies. Further, using the semiconductor films 10 to 12 obtained in the present embodiment, or using the semiconductor film 10 obtained without forming the semiconductor films 11 and 12 in the present embodiment, in the same manner as in the first embodiment. Electronic parts can be manufactured.

  In this embodiment, the second substrate 8 is heated to a temperature lower than the primary phase transition temperature of the material by causing the conductor layer 6 to generate heat, and stress is applied to the first surface of the second substrate 8 on the conductor layer 6 side. The second substrate 8 and the conductor layer 6 are separated from each other. However, by causing the conductor layer 6 to generate heat, the second substrate 8 is heated to a temperature equal to or higher than the primary phase transition temperature of the material, and the second surface of the second substrate 8 on the conductor layer 6 side becomes the second surface. Melting, sublimation or decomposition of the material of the substrate 8 may occur. Also by this, the second substrate 8 and the conductor layer 6 can be separated from each other.

  In the present embodiment, the second substrate 8 is a group III element nitride semiconductor that decomposes into a compound containing a group III element and nitrogen by heating at or above the primary phase transition temperature as described in the above embodiment. There may be.

  In the present embodiment, the semiconductor film 10 and the second substrate 8 may be compound semiconductors made of the same element as described in the above embodiment.

  In the present embodiment, the conductor layer 6 may be made of a magnetic material as described in the above embodiment.

It is process schematic of embodiment of this invention. It is the schematic of the one part process of embodiment of this invention. It is the schematic of the one part process of embodiment of this invention. It is the schematic explaining the arrangement | sequence of the conductor layer in embodiment of this invention. It is the schematic explaining the electromagnetic induction heating in embodiment of this invention. It is process schematic of embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate for film growth 2 Conductor layer 3 Semiconductor film 4 Induction heating coil 5 Dielectric layer 6 Conductor layer 7 First substrate 8 Second substrate 9 Support layers 10, 11, 12 Semiconductor film 20 Device substrate 21 Electrode 22 Insulating layer

Claims (17)

Forming a conductor layer in a partial region of the surface of the film growth substrate;
A step of epitaxially growing a semiconductor from a region other than the partial region on the surface of the film growth substrate to form a semiconductor film covering the conductor layer;
And a step of separating the semiconductor film from the film growth substrate by causing the conductor layer to generate heat by electromagnetic induction.   2. The method of manufacturing a semiconductor film according to claim 1, wherein a dielectric layer or a semiconductor layer is formed on the conductor layer in the step of forming the conductor layer.   A plurality of patterned conductor layers are repeatedly arranged, and the arrangement pitch of the conductor layers is such that the central portion between adjacent conductor layers is heated by heating the conductor layers by the electromagnetic induction. The method of manufacturing a semiconductor film according to claim 1, wherein the semiconductor film is set to have a temperature equal to or higher than the first-order phase transition temperature.   A plurality of patterned conductor layers are repeatedly arranged, and the conductor layers are arranged by causing the conductor layers to generate heat by the electromagnetic induction so that the central portion between adjacent conductor layers is 3. The method of manufacturing a semiconductor film according to claim 1, wherein the semiconductor film manufacturing method is set to a temperature equal to or higher than a first-order phase transition temperature. 4.   5. The method of manufacturing a semiconductor film according to claim 1, wherein the film growth substrate is disposed so as to be perpendicular to a direction of a magnetic force line generated by the electromagnetic induction.   The method for manufacturing a semiconductor film according to claim 1, wherein the conductor layer is made of a material that adsorbs nitrogen.   By heating the conductor layer, the film growth substrate and / or the semiconductor film are heated to a temperature higher than the primary phase transition temperature of these materials, and their interface and / or the semiconductor film and the conductor layer are heated. The material for the film growth substrate and / or the material for the semiconductor film is melted, sublimated, or decomposed at the interface with the substrate to separate the film growth substrate and the semiconductor film from each other. The manufacturing method of the semiconductor film in any one of Claims 1-6.   By heating the conductor layer, the film growth substrate and / or the semiconductor film are heated to a temperature lower than the primary phase transition temperature of these materials, and their interface and / or the semiconductor film and the conductor layer are heated. A stress is generated in the film growth substrate and / or the semiconductor film at an interface with the substrate to separate the film growth substrate and the semiconductor film from each other. A method for producing a semiconductor film as described in 1. above.   9. The semiconductor according to claim 1, wherein the semiconductor is a group III element nitride semiconductor that decomposes into a compound containing a group III element and nitrogen by heating at or above the first phase transition temperature. A method for manufacturing a semiconductor film. Forming a conductor layer on the surface of the first substrate;
Bonding a first surface of a second substrate as a film growth substrate to the surface of the conductor layer;
Forming a semiconductor film by epitaxially growing a semiconductor on a second surface opposite to the first surface of the second substrate;
And a step of separating the second substrate from the first substrate by generating heat in the conductor layer by electromagnetic induction.   By heating the conductor layer, the second substrate is heated to a temperature higher than the first phase transition temperature of the material, and the material of the second substrate is melted and sublimated on the first surface of the second substrate. 11. The method of manufacturing a semiconductor film according to claim 10, wherein decomposition is caused to separate the second substrate and the conductor layer from each other.   Heating the conductive layer to heat the second substrate to less than the first phase transition temperature of the material, generating stress on the second substrate at the first surface, The method of manufacturing a semiconductor film according to claim 10, wherein the conductor layers are separated from each other.   The substrate for film growth or the second substrate is a group III element nitride semiconductor that decomposes into a compound containing a group III element and nitrogen by heating at or above the primary phase transition temperature. The manufacturing method of the semiconductor film in any one of 1-12.   The method of manufacturing a semiconductor film according to claim 1, wherein the semiconductor film and the film growth substrate or the second substrate are compound semiconductors made of the same element.   The method of manufacturing a semiconductor film according to claim 1, wherein the conductor layer is made of a magnetic material.   In the step of separating the semiconductor film from the film growth substrate or the step of separating the second substrate from the first substrate, before the conductor layer is heated by electromagnetic induction, the film growth substrate or The said 2nd board | substrate, the said conductor layer, and the said semiconductor film or the said 1st board | substrate are preheated below those 1st-order phase transition temperatures, The any one of Claims 1-15 characterized by the above-mentioned. Manufacturing method of the semiconductor film.   An electronic component manufacturing method, wherein the semiconductor film is manufactured by the method for manufacturing a semiconductor film according to claim 1, and another member is added to the semiconductor film obtained thereby.

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