JP4834920B2 - Manufacturing method of semiconductor device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor element composed of a nitride compound. Of child Regarding the manufacturing method, in particular, cracks can be reduced, and growth substrate peeling and back surface etching can be performed efficiently. Half The present invention relates to a method for manufacturing a conductor element.
[0002]
[Prior art]
As a material of a semiconductor element generally used as a light emitting source of a light emitting device such as a light emitting diode or a semiconductor laser, for example, GaAs, GaAlAs, GaP, etc. are known for red, orange, yellow, and green light emitting elements. Regarding devices, gallium nitride compound semiconductors such as GaN, InGaN, and GaAlN have been studied as practical blue light emitting materials.
[0003]
Conventionally, a semiconductor growth layer on which semiconductors are stacked is separated into elements by a dicer or a scriber. For example, since a zinc flash structure crystal such as GaP or GaAs has a cleavage property in the “110” direction, it can be easily separated into elements by inserting a scribe line in this direction. However, nitride compound semiconductors have a so-called heteroepi structure that is stacked on a sapphire substrate. Nitride compound semiconductors and sapphire have large lattice constant mismatches, and sapphire is a hexagonal crystal because of its crystalline nature. It does not have a cleavage property. Therefore, the nitride compound semiconductor layer formed on the growth substrate is separated into regions for each element by etching and dicing without scribing.
[0004]
As a method for manufacturing a nitride-based compound semiconductor element that is separated by such etching or dicing, a method described in JP-A-5-343742 is known. This is because when a semiconductor growth layer in which n-type and p-type gallium nitride compound semiconductors are sequentially stacked on a substrate is separated into elements, the sapphire substrate is polished and thinned, and then a part of the p-type layer is n. In this method, etching is performed to the mold layer, the n-type layer is etched or diced to the sapphire substrate, and the sapphire substrate is diced or scribed.
[0005]
In this way, the semiconductor growth layer on the growth substrate separated into regions for each element is formed on the temporary holding substrate together with the sapphire substrate, which is the growth substrate, after a groove reaching the growth substrate is formed by etching or dicing. Then, ablation is generated by a laser beam from the back surface of the sapphire substrate, and individual devices are peeled off from the sapphire substrate to form a nitride compound semiconductor device such as a light emitting diode.
[0006]
[Problems to be solved by the invention]
However, as described in JP-A-5-343742, after forming a groove for element isolation such as etching and dicing in the nitride-based compound semiconductor growth layer to reach the growth substrate, together with the growth substrate In the method of holding on a temporary holding substrate and peeling the sapphire substrate from the back surface by laser ablation and separating it into individual semiconductor elements, the size of each element is as small as several tens of μm, so that cracks occur in the element There is a problem.
[0007]
Furthermore, a micro-sized element is transferred from the growth substrate to the temporary holding substrate by laser ablation, and an adhesive layer is formed on the transfer surface of the temporary holding substrate. Will be ablated, and there is a problem that a good element cannot be held.
[0008]
Therefore, the present invention Half of In the method of manufacturing a conductor element, when a semiconductor growth layer formed on a growth substrate is separated into elements, cracks of the element that occur when the growth substrate is peeled off are prevented and irradiation is performed to peel the growth substrate. The laser beam prevents the adhesive layer on the temporary holding substrate from being ablated, and each semiconductor element can be easily peeled off from the growth substrate. Half It aims at providing the manufacturing method of a conductor element.
[0012]
The method of manufacturing a semiconductor device according to the present invention includes a step of forming an isolation groove having a depth up to a middle portion of the thickness of the semiconductor growth layer in the semiconductor growth layer formed on the first substrate, Separating the semiconductor growth layer from the first substrate and transferring the semiconductor growth layer to the second substrate; and cutting the semiconductor growth layer from the separated surface to the middle portion to separate the semiconductor growth layer for each element. The semiconductor growth layer is formed of a wurtzite compound semiconductor. In order to separate the semiconductor growth layer from the first substrate, ablation by light irradiated through the first substrate is used. It is characterized by that.
[0013]
Since the depth of the element isolation groove formed in the semiconductor growth layer on the sapphire substrate is the depth to the middle of the thickness of the semiconductor growth layer, the semiconductor growth layer is integrated even when the sapphire substrate is peeled off by laser ablation. Since the integrated semiconductor growth layer has a sufficiently large size as compared with a micro-sized element, cracks generated in the semiconductor element when the sapphire substrate is peeled can be reduced.
[0014]
In addition, when the sapphire substrate is peeled off by laser ablation, the semiconductor growth layer is integral. Therefore, when this sapphire substrate is peeled off by laser ablation, the laser beam irradiated from the back surface is grown by the semiconductor growth layer. It is possible to prevent the adhesive layer formed to transfer the layer to the temporary holding substrate, and to prevent the adhesive layer from being ablated by the laser beam, thereby maintaining a good semiconductor element. it can.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0016]
First, a light emitting device in which the second growth layer formed by selective growth has a hexagonal pyramid shape with a substantially triangular cross section will be described as an example.
[0017]
As shown in FIG. 1A, the first growth layer 12 is formed on the growth substrate 11. The growth substrate 11 is not particularly limited as long as it can form a wurtzite type compound semiconductor layer, and various types can be used. For example, as the growth substrate 11, a sapphire substrate having a C plane as a main surface, which is often used when growing a gallium nitride (GaN) compound semiconductor material, can be used. In this case, the C plane as the main surface of the substrate includes a plane orientation inclined within a range of 5 to 6 degrees.
[0018]
As the first growth layer 12 formed on the main surface of the growth substrate 11, a wurtzite type compound semiconductor can be used because a hexagonal pyramid pyramid structure is formed in a later step. For example, a group III compound semiconductor can be used, and further, a gallium nitride (GaN) compound semiconductor, an aluminum nitride (AlN) compound semiconductor, an indium nitride (InN) compound semiconductor, an indium gallium nitride (InGaN) compound A semiconductor, an aluminum gallium nitride (AlGaN) based compound semiconductor, or the like.
[0019]
As a method for growing the first growth layer 12, various vapor phase growth methods can be exemplified. For example, it can be grown using a vapor phase growth method such as an organic metal compound vapor phase growth method (MOCVD (MOVPE) method) or a molecular beam epitaxy method (MBE method), or a hydride vapor phase growth method (HVPE method). . In particular, when the MOVPE method is used, a crystal with good crystallinity can be obtained quickly. Although omitted in FIG. 2, a required buffer layer may be formed on the bottom side of the first growth layer 12.
[0020]
Here, the first growth layer 12 is formed by sequentially laminating an undoped first growth layer 12a and a silicon-doped first growth layer 12b. In general, since the first growth layer 12 functions as a conductive layer for connecting to the n-side electrode, the whole is doped with an impurity such as silicon. However, in the present embodiment, as will be described later, an element isolation groove having a depth up to the middle of the thickness of the semiconductor growth layer is formed in the semiconductor growth layer on the growth substrate, and the semiconductor growth layer is used as a temporary holding substrate. After the semiconductor growth layer is separated from the growth substrate by laser ablation from the back surface of the growth substrate and transferred to the temporary holding substrate, the semiconductor growth layer is shaved from the back surface so as to reach the element isolation groove. The portion of the first growth layer 12a may not be doped with impurities.
[0021]
As shown in FIG. 1B, the growth inhibition comprising a silicon oxide film or a silicon nitride film on the entire surface of the first growth layer 12 in which the undoped first growth layer 12a and the silicon-doped first growth layer 12b are sequentially stacked. A film 13 is formed. The growth inhibition film 13 is a film used as a mask layer, and is formed on the surface of the first growth layer 12 by sputtering or other methods.
[0022]
After the growth inhibition film 13 is formed on the entire surface in this way, as shown in FIG. 1C, a part of the growth inhibition film 13 functioning as a mask is removed to form an opening 13a. The shape of the opening 13a is not particularly limited as long as it can be a facet structure having an inclined surface inclined with respect to the main surface of the substrate, and as an example, a stripe shape, a rectangular shape, a circular shape, an elliptical shape, It is a polygonal shape such as a triangular shape or a hexagonal shape. The surface of the first growth layer 12 below the growth inhibition film 13 is exposed reflecting the shape of the opening 13a.
[0023]
After the opening 13a having such a predetermined shape is formed, a second growth layer is formed by selective growth. As shown in FIG. 2D, a first conductive layer 14, an active layer 15, and a second conductive layer 16 are stacked as a second growth layer by selective growth.
[0024]
Like the first growth layer 12, the first conductive layer 14 is a wurtzite type compound semiconductor layer, and is formed of a material such as silicon-doped GaN. The first conductive layer 14 functions as an n-type cladding layer. The first conductive layer 14 is formed in a hexagonal pyramid shape having a substantially triangular cross section by selective growth when the growth substrate 11 is a sapphire substrate and its main surface is a C plane.
[0025]
The active layer 15 is a layer for generating light of the light emitting element, and includes, for example, an InGaN layer or a layer having a structure in which an InGaN layer is sandwiched between AlGaN layers. The active layer 15 extends along a facet formed of the inclined surface of the first conductive layer 14 and has a thickness suitable for emitting light.
[0026]
The second conductive layer 16 is a wurtzite type compound semiconductor layer, and is formed of a material such as magnesium-doped GaN, for example. The second conductive layer 16 functions as a p-type cladding layer. The second conductive layer 16 also extends along the facet formed of the inclined surface of the first conductive layer 14 and has a thickness suitable for emitting light. The hexagonal pyramid-shaped inclined surface formed by selective growth is a surface selected from, for example, an S surface, a {11-22} surface, and a surface substantially equivalent to each of these surfaces.
[0027]
FIG. 2E and FIG. 2F show a process of forming the element isolation groove 18. As shown in FIG. 2E, in order to prevent the second conductive layer 16 formed on the outermost part from being eroded by the etching for forming the element isolation trench 18, the second conductive layer 16 and the growth inhibiting film 13 are used. The entire surface of the first growth layer 12 on which is formed is covered with a protective film 17. The protective film 17 is, for example, a silicon oxide film formed by a plasma CVD method or the like. After such a protective film 17 is formed, as shown in FIG. 2 (f), a process such as reactive ion etching is performed to form an element isolation groove 18 to be separated into regions for each element.
[0028]
The depth of the element isolation trench 18 is a depth up to the middle of the thickness of the semiconductor growth layer, and is a depth reaching the undoped first growth layer 12a. Therefore, even when the growth substrate 11 is peeled off, the semiconductor growth layer is integrated with the undoped first growth layer 12a, and this integrated semiconductor growth layer is sufficiently large compared to a micro-sized element. Cracks generated in the semiconductor element when the growth substrate 11 is peeled can be reduced. Further, when the growth substrate 11 is peeled off by laser ablation, the semiconductor growth layer is integrated with the undoped first growth layer 12a. Therefore, the undoped first growth layer 12a including the semiconductor growth layer is integrated with the growth substrate 11. Prevents the laser beam irradiated from the back side from reaching the adhesive layer for holding the semiconductor growth layer, and prevents the adhesive layer from being ablated by the laser beam. It is possible to hold a semiconductor element.
[0029]
Then, after the element isolation trench 18 is formed, the protective film 17 is removed with an acid or the like (FIG. 3C). FIG. 3H shows the formation of the p-side electrode 19 on the surface of the second conductive layer 16 that is the outermost part of the hexagonal pyramid-shaped second growth layer after the protective film 17 is removed. As an example, the p-side electrode 19 has a Ni / Pt / Au electrode structure or a Pd / Pt / Au electrode structure, and is formed by vapor deposition or the like. Further, since the n-side electrode is formed at the bottom, it is not formed here.
[0030]
After fixing the semiconductor growth layer to the adhesive layer 20 made of wax, synthetic resin or the like of the temporary holding substrate 21 as shown in FIG. 3 (i), from the back side of the growth substrate 11 as shown in FIG. 4 (i). The laser beam of the excimer laser to be irradiated with ultraviolet rays is irradiated to cause laser ablation, the growth substrate 11 is peeled off, and the semiconductor growth layer is transferred to the temporary holding substrate 21. Since the gallium nitride based semiconductor layer is decomposed into metal gallium and nitrogen at the interface with sapphire, the growth substrate 11 is a sapphire substrate and the first growth layer 12 is a GaN based semiconductor layer. It can be peeled off relatively easily at the interface of the growth layer 12. An excimer laser, a harmonic YAG laser or the like is used as a laser to be irradiated.
[0031]
At this time, since the depth of the element isolation groove 18 is a depth up to the middle of the thickness of the semiconductor growth layer and reaches the undoped first growth layer 12a, even when the growth substrate 11 is peeled off. The semiconductor growth layer is integrated by an undoped first growth layer 12a, and the undoped first growth layer 12a in which the semiconductor growth layer is integrated is irradiated from the back surface to peel off the growth substrate 11 by laser ablation. It is possible to prevent the beam from reaching the adhesive layer 20 for holding the semiconductor growth layer, and to prevent the adhesive layer 20 from being ablated by the laser, so that a good semiconductor element can be held.
[0032]
In FIG. 4K, the first growth layer 12 is etched by etching from the back surface of the semiconductor growth layer transferred to the temporary holding substrate 21 and separated into elements as shown in FIG. Since the first growth layer 12 is separated by the element isolation groove 18, etching is performed from the back surface of the first growth layer 12 to reach the element isolation groove 18, and the semiconductor growth layer is separated into elements. The
[0033]
Usually, in order to form an n-side electrode on the back surface of a semiconductor element having poor crystallinity, a portion having poor crystallinity on the back surface is further removed after element isolation, but the depth of the element isolation groove 18 is undoped. Since the depth reaches the first growth layer 12a, the semiconductor growth layer on the sapphire substrate 11 is cut down to the element isolation trench 18 to separate the semiconductor growth layer into each semiconductor element, so that the semiconductor growth layer is separated into elements and at the same time the crystal The vicinity of the sapphire substrate interface that is not good can be removed, and the n-side electrode 22 can be efficiently formed on the back surface.
[0034]
Then, an n-side electrode 22 is formed on the back surface of the separated element as shown in FIG. For example, the n-side electrode 22 has a Ti / Al / Pt / Au electrode structure and is formed by a vapor deposition method or the like.
[0035]
Thus, the depth of the element isolation groove 18 formed in the semiconductor growth layer on the sapphire substrate 11 is a depth up to the middle of the thickness of the semiconductor growth layer, and the depth reaching the undoped first growth layer 12a. Therefore, even when the sapphire substrate 11 is peeled off by laser ablation, the semiconductor growth layer is integrated on the undoped first growth layer 12a, and this integrated semiconductor growth layer is smaller than a minute size such as an element. Since the size is sufficiently large, cracks that occur when the sapphire substrate 11 is peeled can be reduced.
[0036]
Further, when the sapphire substrate 11 is peeled off by laser ablation, the semiconductor growth layer is integrated on the undoped first growth layer 12a. Therefore, when the sapphire substrate 11 is peeled off by laser ablation, the integrated semiconductor growth layer is removed. The laser beam irradiated from the back surface is prevented from reaching the adhesive layer 20 formed to transfer the semiconductor growth layer to the temporary holding substrate 21, and the adhesive layer 20 is ablated by the laser beam. Therefore, a good semiconductor element can be held.
[0037]
Furthermore, when the sapphire substrate 11 is peeled after the semiconductor growth layer is separated into small-sized elements, it is not easy to remove the sapphire substrate 11 because cracks occur. In the method of manufacturing a semiconductor device according to the present invention in which the depth of the element isolation groove 18 formed in the semiconductor growth layer is a depth up to the middle of the thickness of the semiconductor layer, even when the sapphire substrate 11 is peeled off by laser ablation. The growth layer is integrated by the undoped first growth layer 12a, and the integrated semiconductor growth layer is sufficiently large compared to a minute size such as a device, so that there is no risk of cracks and can be easily performed. The sapphire substrate 11 can be peeled off.
[0038]
In order to form the n-side electrode on the back surface of the semiconductor element having poor crystallinity, the portion having poor crystallinity on the back surface is further removed after element isolation. By cutting up to the element isolation groove 18 for separating into semiconductor elements, the semiconductor growth layer can be separated into elements, and at the same time, the vicinity of the interface of the sapphire substrate having poor crystallinity can be removed, and the n-side electrode 22 is efficiently formed on the back surface. It can be formed well.
[0039]
Next, a planar formed by separating the semiconductor growth layer stacked on the growth substrate by an element isolation groove having a depth up to the middle of the thickness of the semiconductor growth layer formed in the semiconductor growth layer on the growth substrate. A type semiconductor light emitting device will be described.
[0040]
First, as shown in FIG. 6A, the first growth layer 32 is formed on the growth substrate 31. In general, the growth substrate 31 is not particularly limited as long as it can form a wurtzite type compound semiconductor layer next, and various growth substrates 31 can be used. The growth substrate 31 is formed on the main surface of the growth substrate 31. Various growth layers 32 can be used. As the first growth layer 32, for example, a group III compound semiconductor can be used, and a gallium nitride (GaN) compound semiconductor, an aluminum nitride (AlN) compound semiconductor, an indium nitride (InN) compound semiconductor, and indium nitride. Examples include a gallium (InGaN) compound semiconductor and an aluminum gallium nitride (AlGaN) compound semiconductor.
[0041]
Here, GaAs used in the planar red light emitting element is used as the growth substrate 31 and AlAs is used as the material of the first growth layer 32. By using AlAs as the first growth layer 32, as will be described later, an element isolation groove having a depth up to a middle portion of the thickness of the semiconductor growth layer is formed in the semiconductor growth layer on the growth substrate 31, and semiconductor growth is performed. After the layer is held on the temporary holding substrate and the semiconductor growth layer is separated from the growth substrate 31 and transferred to the temporary holding substrate, when the semiconductor growth layer is scraped from the back surface so as to reach the element isolation trench, AlAs is hydrofluoric acid. The first growth layer 32 of AlAs can be easily removed and the growth substrate 31 can be peeled off due to the property of being easily dissolved in the substrate.
[0042]
As a method for growing the first growth layer 32, various vapor phase growth methods can be exemplified. For example, it can be grown using a vapor phase growth method such as an organometallic compound vapor phase growth method (MOVPD (MOVPE) method) or a molecular beam epitaxy method (MBE method), or a hydride vapor phase growth method (HVPE method). . In particular, when the MOVPE method is used, a crystal with good crystallinity can be obtained quickly. Although omitted in FIG. 6A, a required buffer layer may be formed on the bottom side of the first growth layer 32 made of AlAs.
[0043]
6B, the n-side contact layer 33, the first conductive layer 34, the active layer 35, the second conductive layer 36, and the p-side contact layer 37 are sequentially formed on the first growth layer 32 made of AlAs. Are stacked to form a second growth layer.
[0044]
In general, the n-side contact layer 33 and the first conductive layer 34 are wurtzite type compound semiconductor layers like the first growth layer 32, and are made of a material such as silicon-doped GaN. The first conductive layer 34 functions as an n-type cladding layer. The active layer 35 is a layer for generating light of the light emitting element, is stacked on the first conductive layer 34, and has a thickness suitable for emitting light. The p-side contact layer 37 and the second conductive layer 36 are wurtzite type compound semiconductor layers, and are formed of a material such as magnesium-doped GaN, for example. The second conductive layer 35 functions as a p-type cladding layer.
[0045]
As described above, various materials can be used for each layer of the second growth layer. In this embodiment, GaAs is used as the n-side contact layer 33, AlGaInP is used as the first conductive layer 34, GaInP is used as the active layer 35, AlGaInP is used as the second conductive layer 36, and GaAs is used as the p-side contact layer 37.
[0046]
FIG. 6C shows a step of forming the element isolation trench 38 in the semiconductor growth layer stacked on the GaAs growth substrate 31. The element isolation trench 38 is formed by performing a process such as reactive ion etching, and the semiconductor growth layer is separated into regions for each element.
[0047]
The depth of the element isolation trench 38 is a depth up to the middle of the thickness of the semiconductor growth layer, and reaches the first growth layer 32 of AlAs but does not reach the GaAs growth substrate 31. Therefore, as will be described later, the first growth layer 32 made of AlAs is removed using hydrofluoric acid and the GaAs growth substrate 31 is peeled off. At the same time, the semiconductor growth layer is separated into semiconductor elements, and the GaAs growth substrate 31 can be easily removed. Can be peeled off.
[0048]
FIG. 7D shows the formation of the p-side electrode 39 on the surface of the p-side contact layer 37 at the top of the second growth layer. As an example, the p-side electrode 39 has a Ti / Pt / Au electrode structure or a Ni (Pd) / Pt / Au electrode structure, and is formed by a vapor deposition method or the like. Further, since the n-side electrode is formed at the bottom, it is not formed here.
[0049]
As shown in FIG. 7E, the semiconductor growth layer is held in the adhesive layer 40 made of wax, synthetic resin or the like formed on the transfer surface of the temporary holding substrate 41, and as shown in FIG. Is used to remove the first growth layer 32 of AlAs and the GaAs growth substrate 31 is peeled off. Since AlAs has a property of being easily dissolved in hydrofluoric acid, the first growth layer 32 made of AlAs can be easily removed, and the growth substrate 31 can be peeled off. Further, the depth of the element isolation trench 38 is a depth up to the middle part of the thickness of the semiconductor growth layer, and the depth reaching the first growth layer 32 of AlAs. Therefore, the first isolation layer 38 is made of AlAs using hydrofluoric acid. At the same time that the growth layer 32 is removed and the GaAs growth substrate 31 is peeled off, the semiconductor growth layer separated into regions for each element is separated into semiconductor elements.
[0050]
Then, the plurality of semiconductor elements held on the temporary holding substrate 41 are etched from the back surface, and the n-side electrode 42 is formed as shown in FIG. For example, the n-side electrode 42 has an AuGe / Ni / Au electrode structure and is formed by a vapor deposition method or the like.
[0051]
As described above, since the depth of the element isolation groove formed in the semiconductor growth layer on the growth substrate is a depth to the middle of the thickness of the semiconductor growth layer, the semiconductor growth layer is integrated even when the growth substrate is peeled off. In addition, since this integrated semiconductor growth layer has a sufficiently large size compared to a minute size such as an element, it is possible to reduce cracks that occur when the growth substrate is peeled off.
[0052]
Also, when the growth substrate is peeled after separating the semiconductor growth layer into small-sized elements, it is not easy to take care of peeling the growth substrate due to cracks. In the method of manufacturing a semiconductor device according to the present invention in which the depth of the element isolation groove formed in the semiconductor layer is a depth up to the middle of the thickness of the semiconductor layer, the integrated semiconductor growth layer is like an element even when the growth substrate is peeled off. The growth substrate can be easily peeled off without causing cracks at a sufficiently large size compared to a very small size.
[0053]
【The invention's effect】
In the semiconductor device and the manufacturing method thereof according to the present invention, the depth of the element isolation groove formed in the semiconductor growth layer on the sapphire substrate is the depth to the middle of the thickness of the semiconductor growth layer. Even when the first growth layer is peeled off by peeling off with acid or the like, the semiconductor growth layer is integrated, and this integrated semiconductor growth layer has a sufficiently large size compared to a micro size like a device. Therefore, the crack which arises when peeling a sapphire substrate can be reduced.
[0054]
In addition, when the sapphire substrate is peeled off by laser ablation, the semiconductor growth layer is integral. Therefore, when this sapphire substrate is peeled off by laser ablation, the laser beam irradiated from the back surface is grown by the semiconductor growth layer. It is possible to prevent the adhesive layer formed to transfer the layer to the temporary holding substrate, and to prevent the adhesive layer from being ablated by the laser beam, thereby maintaining a good semiconductor element. it can.
[0055]
Furthermore, when the sapphire substrate is peeled after separating the semiconductor growth layer into small-sized elements, it is not easy to take care of peeling the sapphire substrate because of cracks, but the semiconductor growth layer on the sapphire substrate In the method for manufacturing a semiconductor device of the present invention, in which the depth of the element isolation groove formed in the semiconductor layer is a depth up to the middle of the thickness of the semiconductor layer, the first growth layer is peeled off by laser ablation or the first growth layer is formed by acid, etc. Even when removed and peeled off, the integrated semiconductor growth layer can be easily peeled off from the sapphire substrate without the possibility of cracking at a sufficiently large size compared to the micro size of the element.
[0056]
In order to form an electrode on the back surface of a semiconductor element having poor crystallinity, the portion having poor crystallinity on the back surface is further removed after element isolation. A semiconductor growth layer on a sapphire substrate is formed on each semiconductor element. By separating the semiconductor growth layer into elements by removing the element isolation trench having a depth up to the middle part of the thickness of the semiconductor growth layer in order to isolate, the vicinity of the interface of the sapphire substrate having poor crystallinity can be removed. And the electrodes can be efficiently formed on the back surface.
[Brief description of the drawings]
FIG. 1 shows a process for forming a first growth layer, a growth inhibition film, and an opening in a method for manufacturing a semiconductor device according to an embodiment of the present invention. FIG. b) is a process cross-sectional view of growth inhibition film formation, and (c) is a process cross-sectional view of opening formation.
FIG. 2 shows a process of forming a second growth layer and an element isolation groove in the method for manufacturing a semiconductor device according to the embodiment of the present invention, (d) is a process cross-sectional view of the second growth layer formation, (e) It is process sectional drawing of protective film formation, (f) is process sectional drawing of element isolation groove formation.
FIGS. 3A and 3B show a step of forming a p-side electrode and a step of peeling a growth substrate in a method for manufacturing a semiconductor device according to an embodiment of the present invention, FIG. It is process sectional drawing of side electrode formation, (i) is process sectional drawing of adhesion | attachment to the board | substrate for temporary holding.
FIGS. 4A and 4B show a process for peeling a growth substrate and a process for separating a semiconductor growth layer in a method for manufacturing a semiconductor device according to an embodiment of the present invention. FIG. It is process sectional drawing of an etching process, (l) It is process sectional drawing of element isolation.
FIG. 5 shows a process of forming an n-side electrode in the method for manufacturing a semiconductor device according to the embodiment of the present invention, and FIG.
FIG. 6 shows a process for forming a first growth layer, a second growth layer, and an element isolation groove in a method for manufacturing a semiconductor device according to an embodiment of the present invention, wherein FIG. (B) is process sectional drawing of a 2nd growth layer, (c) is process sectional drawing of element isolation groove | channel formation.
7A and 7B show a step of forming a p-side electrode and holding a semiconductor growth layer in a method for manufacturing a semiconductor device according to an embodiment of the present invention, wherein FIG. It is process sectional drawing of a growth layer holding | maintenance.
8A and 8B show a process of peeling a growth substrate and forming an n-side electrode in a method for manufacturing a semiconductor device according to an embodiment of the present invention, and FIG. It is process sectional drawing of n side electrode formation.
[Explanation of symbols]
11,31 Growth substrate
12,32 First growth layer
12a Undoped first growth layer
12b doped first growth layer
13 Growth inhibition film
13a opening
14,34 First conductive layer
15,35 active layer
16, 36 Second conductive layer
17 Protective film
18,38 element isolation groove
19,39 p-side electrode
20,40 Adhesive layer
21,41 Temporary holding substrate
22,42 n-side electrode
33 n-side contact layer
37 p-side contact layer

Claims (7)

In a method for manufacturing a semiconductor element for separating a semiconductor growth layer formed on a first substrate into elements,
Forming a separation groove having a depth to the middle of the thickness of the semiconductor growth layer;
Separating the semiconductor growth layer from the first substrate and transferring the semiconductor growth layer to a second substrate;
Cutting the semiconductor growth layer from the separated surface to the midway part, and separating the semiconductor growth layer for each element,
The semiconductor growth layer is formed from a wurtzite compound semiconductor ,
Separation of the semiconductor growth layer from the first substrate uses ablation by light irradiated through the first substrate . 2. The method of manufacturing a semiconductor device according to claim 1, wherein the semiconductor growth layer is formed of an undoped wurtzite compound semiconductor up to the middle portion, and is formed of a silicon-doped wurtzite compound semiconductor from the middle portion. The method for manufacturing a semiconductor device according to claim 1, wherein the wurtzite compound semiconductor is a nitride compound semiconductor. The method for manufacturing a semiconductor device according to claim 1, wherein the first substrate is a sapphire substrate. The method for manufacturing a semiconductor device according to claim 1, wherein the semiconductor growth layer is separated from the first substrate by removing a part of the semiconductor growth layer. The method for manufacturing a semiconductor device according to claim 1, wherein an adhesive layer is formed on the semiconductor growth layer holding surface of the second substrate. The semiconductor growth layer forms a crystal layer having an inclined crystal plane inclined with respect to a main surface of the first substrate on the first substrate,
A first conductive layer, an active layer, and a second conductive layer extending in a plane parallel to the inclined crystal plane are formed on the crystal layer, or the main surface of the first substrate on the first substrate A crystal layer to be laminated is formed, and a first conductive layer, an active layer, and a second conductive layer extending in a plane parallel to the main surface are formed on the crystal layer. A method for producing a semiconductor device according to 1.

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