Optical element substrate manufacturing method, optical communication substrate, optical communication device, optical element substrate, and optical communication substrate manufacturing method

Abstract

This light-emitting element substrate manufacturing method includes: a step for preparing a semiconductor substrate comprising a main substrate, a first seed pattern that includes a first seed portion, a second seed pattern that includes a second seed portion, a first semiconductor layer that is bonded to the first seed portion and that includes a nitride semiconductor, and a second semiconductor layer that is bonded to the second seed portion and that includes a nitride semiconductor; and a step for forming a first functional layer that is positioned on the first semiconductor layer and that has a light-emitting function and a second functional layer that is positioned on the second semiconductor layer and that has a light-receiving function.

Description

Method for manufacturing optical element substrate, optical communication substrate, optical communication device, optical element substrate, and method for manufacturing optical communication substrate

[0001] The present disclosure relates to an optical element substrate and the like.

[0002] Patent Document 1 discloses a communication device using a GaN-based micro LED.

[0003] Japanese Patent Application Laid-Open No. 2024-141946

[0004] A method for manufacturing an optical element substrate according to the present disclosure is a semiconductor comprising: a main substrate; a first seed pattern including a first seed portion; a second seed pattern including a second seed portion; a first semiconductor layer bonded to the first seed portion and containing a nitride semiconductor; and a second semiconductor layer bonded to the second seed portion and containing a nitride semiconductor, wherein the first seed pattern and the second seed pattern are arranged above the main substrate along a first direction, the first seed portion and the second seed portion have a longitudinal direction that is a second direction orthogonal to the first direction, the first semiconductor layer has a first base portion extending upward from the first seed portion and a first wing portion extending from the first base portion in the first direction, and the second semiconductor layer has a second base portion extending upward from the second seed portion and a second wing portion extending from the second base portion in the first direction. The method includes: a step of preparing a substrate; and a step of forming a first functional layer that is located on the first semiconductor layer and has a light-emitting function, and a second functional layer that is located on the second semiconductor layer and has a light-receiving function.

[0005] This is a plan view showing an example of a method for manufacturing this optical element substrate. This is a flowchart showing an example of a method for manufacturing this optical element substrate. This is a plan view showing an example of a method for manufacturing this optical element substrate. This is a cross-sectional view showing an example of a method for manufacturing this optical element substrate. This is a cross-sectional view showing an example of a method for manufacturing this optical element substrate. This is a plan view showing an example of a method for manufacturing this optical element substrate. This is a plan view showing an example of a method for manufacturing this semiconductor substrate. This is a flowchart showing an example of a method for manufacturing this optical communication substrate. This is a plan view showing an example of a method for manufacturing this optical communication substrate. This is a plan view showing an example of a method for manufacturing this optical communication substrate. This is a cross-sectional view showing an example of a method for manufacturing this optical communication substrate. This is a cross-sectional view showing an example of a method for manufacturing this optical communication substrate. This is a cross-sectional view showing an example of a method for manufacturing this semiconductor substrate. This is a plan view showing an example of a method for manufacturing this optical communication substrate. This is a plan view showing an example of a method for manufacturing this optical communication substrate. This is a plan view showing an example of a method for manufacturing this optical communication substrate. This is a flowchart showing an example of a method for manufacturing this optical communication substrate. This is a flowchart showing an example of a method for manufacturing this optical communication substrate. This is a cross-sectional view showing an example of a method for manufacturing this optical communication substrate. This is a plan view showing an example of a method for manufacturing this optical communication substrate. This is a plan view showing an example of a configuration of an optical light-emitting layer (first functional layer) and a photodetector layer (second functional layer). This is a plan view showing an example of a configuration of an optical light-emitting layer (first functional layer) and a photodetector layer (second functional layer). This is a plan view showing an example configuration of a light-emitting element layer (first functional layer) and a photodetector layer (second functional layer). This is a plan view showing an example configuration of a light-emitting element layer (first functional layer) and a photodetector layer (second functional layer). This is a plan view showing an example configuration of a light-emitting element layer (first functional layer) and a photodetector layer (second functional layer). This is a plan view showing an example configuration of a light-emitting element layer (first functional layer) and a photodetector layer (second functional layer). This is a cross-sectional view showing an example of a method for manufacturing this semiconductor substrate. This is a cross-sectional view showing an example of a method for manufacturing this semiconductor substrate. This is a cross-sectional view showing an example of a method for manufacturing this optical communication substrate. This is a cross-sectional view showing an example of a method for manufacturing this optical communication substrate. This is a cross-sectional view showing an example of a method for manufacturing this optical communication substrate. This is a flowchart showing an example of a method for manufacturing an optical communication device. This is a cross-sectional view showing an example of a method for manufacturing an optical communication device. This is a cross-sectional view showing an example configuration of this information processing device. This is a flowchart showing an example of a method for manufacturing an optical communication substrate.This is a cross-sectional view showing an example of a method for manufacturing an optical communication substrate. block diagram showing an example of the configuration of the manufacturing apparatus for this optical element substrate. This is a block diagram showing an example of the configuration of the manufacturing apparatus for this optical communication substrate.

[0006] Figure 1 is a plan view showing an example of a method for manufacturing this optical element substrate. Figure 2 is a flowchart showing an example of a method for manufacturing this optical element substrate. Figure 3 is a plan view showing an example of a method for manufacturing this optical element substrate. Figures 4 and 5 are cross-sectional views showing an example of a method for manufacturing this optical element substrate. In the following, the description of "numerical value A to numerical value B" with respect to physical quantities means that the physical quantity is greater than or equal to A and less than or equal to B. As shown in Figures 1 to 5, the method for manufacturing an optical element substrate according to this embodiment includes a step S5 of preparing a semiconductor substrate 10 having a first semiconductor layer L1 and a second semiconductor layer L2, and a step S15 of forming a first functional layer K1 located on the first semiconductor layer L1 and having an emitting function, and a second functional layer K2 located on the second semiconductor layer L2 and having a light receiving function. The light receiving function is, for example, a photoelectric conversion function that converts light into an electrical signal.

[0007] The semiconductor substrate 10 comprises a main substrate 1, a first seed pattern P1 including a first seed portion S1, a second seed pattern P2 including a second seed portion S2, a first semiconductor layer L1 bonded to the first seed portion S1 and containing a nitride semiconductor, and a second semiconductor layer L2 bonded to the second seed portion S2 and containing a nitride semiconductor. The first seed pattern P1 may include a plurality of seed portions S arranged in a stripe pattern in a first direction D1. The second seed pattern P2 may include a plurality of seed portions S arranged in a stripe pattern in the first direction D1. The first seed portion S1 is the growth starting point of the first semiconductor layer L1 containing a nitride semiconductor. The second seed portion S2 is the growth starting point of the second semiconductor layer L2 containing a nitride semiconductor.

[0008] As shown in Figures 1 to 5, the first seed pattern P1 and the second seed pattern P2 are arranged above the main substrate 1 along the first direction D1 (aligned with the first direction D1). The first seed portion S1 and the second seed portion S2 have the second direction D2, which is perpendicular to the first direction D1, as their longitudinal direction. The first semiconductor layer L1 has a first base portion X1 extending upward from the first seed portion S1 and a first wing portion W1 extending from the first base portion X1 along the first direction D1. The second semiconductor layer L2 has a second base portion X2 extending upward from the second seed portion S2 and a second wing portion W2 extending from the second base portion X2 along the first direction D1. The two wing portions extending from the first base portion X1 in the positive direction (direction of the arrow) and negative direction of the first direction D1 are each referred to as the first wing portion W1. The two wing sections extending from the second base X2 in the positive direction (direction of the arrow) and the negative direction of the first direction D1 are referred to as the second wing section W2.

[0009] By steps S5 and S15, an optical device substrate DK (nitride semiconductor-based optical device substrate) can be obtained, on which a first functional layer K1 having an emissive function and a second functional layer K2 having a light-receiving function are formed on a semiconductor substrate 10 containing a nitride semiconductor. Then, by transferring at least a portion of the first semiconductor layer L1 and the first functional layer K1, and at least a portion of the second semiconductor layer L2 and the second functional layer K2 to another substrate, a nitride semiconductor-based light-emitting and light-receiving substrate (for example, an optical communication substrate) can be obtained (described later).

[0010] A crystal growth substrate (template substrate) TK may be configured to include a main substrate 1, first and second seed patterns P1 and P2, and a mask pattern 6 including a mask portion 5. A base substrate may be configured to include the main substrate 1 and the first and second seed patterns P1 and P2. The main substrate 1 may be a different type of substrate with a different lattice constant from the nitride semiconductor of the first and second semiconductor layers L1 and L2.

[0011] The first and second seed patterns P1 and P2 are inverted patterns of the mask pattern 6. In a plan view, the first and second seed portions S1 and S2 are located at the openings of the mask pattern 6. A plan view is when an object (optical element substrate DK, crystal growth substrate TK, etc.) is viewed in the direction normal to the main substrate 1 (including perspective), and in a cross-sectional view, it can be said to be a view from top to bottom or bottom to top (perspective). The first and second seed portions S1 and S2 have a longitudinal shape, with the first direction D1 (the a-axis direction of the first semiconductor L1) being the short-side direction, and the second direction D2 (the m-axis direction of the first semiconductor L1), which is perpendicular to the first direction D1, being the longitudinal direction.

[0012] The mask portion 5 may function as a growth-inhibiting (selective growth) mask. The first and second wing portions W1 and W2 may extend above the mask portion 5 in the first direction D1. Silicon nitride, silicon oxide, and the like can be used for the mask portion 5.

[0013] In the optical element substrate DK, a first functional layer K1 may be formed on each of two paired first wing portions W1 (extending in opposite directions from the first base portion X1). In the optical element substrate DK, a second functional layer K2 may be formed on each of two paired second wing portions W2 (extending in opposite directions from the second base portion X2). The first functional layer K1 may be a light-emitting layer H, and the second functional layer K2 may be a light-receiving element layer J. Multiple light-emitting layers H arranged in a second direction D2 may be formed on the first wing portion W1 of the first semiconductor layer L1. Multiple light-receiving element layers J arranged in a second direction D2 may be formed on the second wing portion W2 of the second semiconductor layer L2.

[0014] The first seed pattern P1 may include a third seed section S3 adjacent to the first seed section S1. The second seed pattern P2 may include a fourth seed section S4 adjacent to the second seed section S2. The third seed section S3 and the fourth seed section S4 may have the second direction D2 as their longitudinal direction.

[0015] The semiconductor substrate 10 may include a third semiconductor layer L3 bonded to a third seed portion S3 and containing a nitride semiconductor, and a fourth semiconductor layer L4 bonded to a fourth seed portion S4 and containing a nitride semiconductor. The third semiconductor layer L3 may have a third base portion X3 extending upward from the third seed portion S3 and a third wing portion W3 extending in a first direction D1 from the third base portion X3. The fourth semiconductor layer L4 may have a fourth base portion X4 extending upward from the fourth seed portion S4 and a fourth wing portion W4 extending in a first direction D1 from the fourth base portion X4. Hereinafter, the first to fourth seed portions S1 to S4 may be collectively referred to as seed portion S, and the first to fourth semiconductor layers L1 to L4 may be collectively referred to as semiconductor layer L. The first to fourth wing portions W1 to W4 may be collectively referred to as wing portion W.

[0016] In step S15 (Figure 2), a third functional layer K3 located on the third semiconductor layer L3 and having an emitting function, and a fourth functional layer K4 located on the fourth semiconductor layer L4 and having a light-receiving function may be formed. In step S15, the first functional layer K1, the second functional layer K2, the third functional layer K3, and the fourth functional layer K4 may be formed simultaneously (simultaneous formation of the light-emitting layer and the light-receiving layer). In step S15, the second functional layer K2 and the fourth functional layer K4 (light-receiving layer) may be formed simultaneously before or after the simultaneous formation of the first functional layer K1 and the third functional layer K3 (light-emitting layer). Hereinafter, the first to fourth functional layers K1 to K4 may be collectively referred to as functional layer K.

[0017] The semiconductor layer L contains a nitride semiconductor. The semiconductor layer L may be a nitride semiconductor crystal. The functional layer K may contain a nitride semiconductor. The functional layer K may contain electrodes (e.g., a metal layer, a metal oxide layer). The functional layer K may contain an insulating film IS. The first functional layer K1 and the second functional layer K2 may have the same (common) layer configuration (stacked structure and composition) of nitride semiconductors. The first functional layer K1, the second functional layer K2, the third functional layer K3, and the fourth functional layer K4 may have the same (common) layer configuration (stacked structure and composition) of nitride semiconductors.

[0018] The semiconductor layer L contains a nitride semiconductor as its main component. A nitride semiconductor can be represented, for example, as AlxGayInzN (0≦x≦1; 0≦y≦1; 0≦z≦1; x+y+z=1). Specific examples of nitride semiconductors include GaN-based semiconductors, AlN (aluminum nitride), InAlN (indium aluminum nitride), and InN (indium nitride). A GaN-based semiconductor is a semiconductor containing gallium atoms (Ga) and nitrogen atoms (N), and typical examples include GaN, AlGaN, AlGaInN, and InGaN. The first and semiconductor layers L1 and L2 may be doped (e.g., n-type including a donor) or undoped.

[0019] The first direction D1 may be the a-axis direction (<11-20> direction) of the nitride semiconductor contained in the semiconductor layer L. The second direction D2, which is orthogonal to the first direction D1, may be the m-axis direction (<1-100> direction) of the nitride semiconductor. The third direction D3, which is orthogonal to the first and second directions D1 and D2, may be the c-axis direction (<0001> direction) of the nitride semiconductor.

[0020] The main substrate 1 may be a self-supporting, heterogeneous substrate (such as a silicon substrate, sapphire substrate, or silicon carbide substrate) with a different lattice constant from the semiconductor layer L (for example, a nitride semiconductor crystal). The term "semiconductor substrate 10" means a substrate containing a semiconductor, and the main substrate 1 may contain a semiconductor (for example, silicon, silicon carbide) or it may not contain a semiconductor. An example of a main substrate 1 that does not contain a semiconductor is a sapphire substrate.

[0021] In the semiconductor substrate 10, the spacing d1 between the first seed portion S1 and the third seed portion S3 may be different from the spacing d2 between the second seed portion S2 and the fourth seed portion S4. The spacing d1 between the first seed portion S1 and the third seed portion S3 may be larger than the spacing d2 between the second seed portion S2 and the fourth seed portion S4. The first semiconductor layer L1 and the third semiconductor layer L3 may be adjacent to each other with a first gap G1 in between, and the second semiconductor layer L2 and the fourth semiconductor layer L4 may be adjacent to each other with a second gap G2 in between. The width of the first wing portion W1 (length in the first direction D1) may be larger than the width of the second wing portion W2 (length in the first direction D1). The width of the third wing portion W3 (length in the first direction D1) may be larger than the width of the fourth wing portion W4 (length in the first direction D1). The first gap G1 may be smaller than the second gap G2.

[0022] The through-dislocation density of the first wing portion W1 may be 1 / 5 or less of the through-dislocation density of the first base portion X1. The first direction D1 may be the a-axis direction of the nitride semiconductor contained in the semiconductor layer L. The second direction D2 may be the m-axis direction of the nitride semiconductor contained in the semiconductor layer L.

[0023] The semiconductor substrate 10 may have light-emitting regions AH including a first seed pattern P1 and light-receiving regions AJ including a second seed pattern P2 arranged alternately in the first direction D1.

[0024] The first wing portion W1 and the second wing portion W2 may each face the crystal growth substrate TK via a gap GD. The first wing portion W1 and the second wing portion W2 may each be floating above the mask portion (non-seed portion) 5 of the crystal growth substrate TK.

[0025] The crystal growth substrate TK may have a ridge portion R. The upper part of the ridge portion R may be the first seed portion S1. The ridge portion R may have a protrusion on the upper surface of the main substrate. The first and second seed portions S1 and S2 may contain a nitride semiconductor.

[0026] The light-emitting function of the first functional layer K1 may be that of a light-emitting diode or a laser diode. The light-receiving function of the second functional layer K2 may be that of a photodiode.

[0027] As shown in Figure 5, the first functional layer K1 may include the first electrode HP. The second functional layer K2 may include the second electrode JP, which has a longer length in the first direction D1 than the first electrode HP. The first functional layer K1 may include the first active layer HM. The second functional layer K2 may include the second active layer JM, which has a higher indium concentration than the first active layer HM. The second active layer JM may have a higher indium composition ratio than the first active layer HM.

[0028] As shown in Figures 1 to 5, the widths (lengths in the first direction D1) of the first seed portion S1 and the second seed portion S2 may be equal. Figure 6 is a plan view showing an example of a method for manufacturing the optical element substrate. As shown in Figure 6, the width F1 (length in the first direction D1) of the first seed portion S1 may be greater than the width F2 (length in the first direction D1) of the second seed portion S2.

[0029] As shown in Figures 1 to 6, the optical element substrate DK comprises a main substrate 1, a first seed pattern P1 including a first seed portion S1, a second seed pattern P2 including a second seed portion S2, a first semiconductor layer L1 bonded to the first seed portion S1 and containing a nitride semiconductor, a second semiconductor layer L2 bonded to the second seed portion S2 and containing a nitride semiconductor, a first functional layer K1 located on the first semiconductor layer L1, and a second functional layer K2 located on the second semiconductor layer L2.

[0030] In the optical element substrate DK, the first semiconductor layer L1 includes a first base X1 extending upward from the first seed portion S1 and a first wing portion W1 extending in a first direction D1 from the first base portion X1. The second semiconductor layer L2 includes a second base X2 extending upward from the second seed portion S2 and a second wing portion W2 extending in a first direction D1 from the second base portion X2. The first seed portion S1 and the second seed portion S2 have a longitudinal direction in the second direction D2 which is perpendicular to the first direction D1. The first functional layer K1 is a light-emitting element layer H. The second functional layer K2 is a light-receiving element layer J.

[0031] Figure 7 is a plan view showing an example of a method for manufacturing this semiconductor substrate. As shown in Figure 7, by making the spacing d1 between the first seed portion S1 and the third seed portion S3 larger than the spacing d2 between the second seed portion S2 and the fourth seed portion S4, the amount of raw material supplied onto the first seed pattern P1 is greater than that supplied onto the second seed pattern P2, and the width of the first wing portion W1 can be made larger than that of the second wing portion W2. In addition, the second gap G2 can be made larger than the first gap G1. In this way, when the first and second functional layers K1 and K2 are formed, the concentration of indium incorporated into the second functional layer K2 is higher than that of the first functional layer K1. As a result, when the first functional layer K1 and the second functional layer K2 are formed in the same process, the effective wavelength band of the first functional layer K1 can be made shorter compared to that of the second functional layer K2. Since light-receiving elements tend to have shorter wavelengths compared to light-emitting elements, the first functional layer K1 can be made into a light-emitting layer H and the second functional layer K2 into a light-receiving element layer J in order to bring the wavelengths of the light-emitting and light-receiving elements closer together.

[0032] The spacing d1 between the first seed section S1 and the third seed section S3 is preferably approximately an integer multiple of the spacing d2 between the second seed section S2 and the fourth seed section S4. This allows for efficient one-to-one mounting of light-receiving elements and light-emitting elements in the process of transferring the first functional layer K1 and the second functional layer K2 to a separate substrate (mounting substrate, transfer substrate). Basically, by matching the pitch of adjacent light-emitting elements and adjacent light-receiving elements to the pitch of bundled optical transmission fibers (fiber pitch), an optical transmission module with high optical utilization efficiency can be manufactured at low cost.

[0033] Figure 8 is a flowchart showing an example of a method for manufacturing the optical communication substrate. Figures 9 and 10 are plan views showing an example of a method for manufacturing the optical communication substrate. Figures 11 and 12 are cross-sectional views showing an example of a method for manufacturing the optical communication substrate. As shown in Figures 9 to 12, in step S25 following step S15, the light-emitting element portion HY, which includes at least a part of the first semiconductor layer L1 and the first functional layer K1, and the light-receiving element portion JY, which includes at least a part of the second semiconductor layer L2 and the second functional layer K2, are separated from the crystal growth substrate TK and transferred to the mounting substrate MK. This results in an optical communication substrate EK comprising the first functional layer K1 and the second functional layer K2 and the mounting substrate MK.

[0034] In the first semiconductor layer L1, the base X1 is bonded to the first seed portion S1, the first functional layer K1 is located on the first wing portion W1, and the second functional layer K2 is located on the second wing portion W2. As shown in Figures 11 and 12, the transfer of the first functional layer K1 and the second functional layer K2 to the mounting substrate MK is easy.

[0035] Because the first wing portion W1 and the second wing portion W2 have a lower threading dislocation density compared to the base portions X1 and X2, the quality (crystallinity) of the first functional layer K1 and the second functional layer K2 is improved, and the light emission characteristics and light receiving (photodetection) characteristics can be enhanced. In particular, in the second functional layer K2, which extracts electrons generated in the active layer from the n-type semiconductor layer, the crystallinity of the n-type semiconductor layer on the wing portion W2 is improved, which can lead to improved detection accuracy.

[0036] As shown in Figure 12, the first functional layer K1 may include a first lower layer HS containing an n-type semiconductor layer (e.g., an n-type nitride semiconductor layer), a first active layer HM, a first upper layer HT containing a p-type semiconductor layer (e.g., a p-type nitride semiconductor layer), and an electrode HP (e.g., a p-electrode, anode). The second functional layer K2 may include a second lower layer JS containing an n-type semiconductor layer (e.g., an n-type nitride semiconductor layer), a second active layer JM, a second upper layer JT containing a p-type semiconductor layer (e.g., a p-type nitride semiconductor layer), and an electrode JP (e.g., a p-electrode). In step S25, as shown in Figures 11 and 12, the first wing portion W1 may be broken to separate it from the crystal growth substrate TK, and the second wing portion W2 may be broken to separate it from the crystal growth substrate TK. For example, the first and second wing portions W1 and W2 may each include a tether portion TZ. The tether portion TZ is a region adjacent to the base where the length in the second direction D2 is smaller (than the length in the second direction D2 of the central portion), and the tether portion TZ may be broken during the transfer of the first functional layer K1 and the second functional layer K2.

[0037] During the transfer of the first functional layer K1 and the second functional layer K2, the first functional layer K1 may be connected to the pad HV of the mounting substrate MK via the solder layer 17, and the second functional layer K2 may be connected to the pad JV of the mounting substrate MK via the solder layer 18. The solder layer 17 connected to the pad HV may hold the first functional layer K1 by covering at least a portion of it, and the solder layer 18 connected to the pad JV may hold the second functional layer K2 by covering at least a portion of it. Instead of the solder layer 17, an anisotropic conductive layer 17 that is conductive only in the third direction D3 may be applied.

[0038] Figure 13 is a cross-sectional view showing an example of a method for manufacturing this semiconductor substrate. As shown in Figure 13, the first and second semiconductor layers L1 and L2 can be formed by the ELO (Epitaxial Lateral Overgrowth) method, starting from the first and second seed portions S1 and S2. For example, the base portion X1 of the first semiconductor layer L1, located above the first seed portion S1, becomes a dislocation inheritance portion with many through-dislocations. For example, the first and second wing portions W1 and W2 become low-defect portions with a smaller through-dislocation density compared to the dislocation inheritance portion.

[0039] Figures 14 and 15 are plan views showing an example of a method for manufacturing the optical communication substrate. As shown in Figures 14 and 15, a first functional layer K1 may be formed over two paired first wing portions W1 and a first base portion X1, and a second functional layer K2 may be formed over two paired second wing portions W2 and a second base portion X2.

[0040] Figure 16 is a plan view showing an example of a method for manufacturing this optical communication substrate. As shown in Figure 16, the first and second semiconductor layers L1 and L2 may be patterned before step S25 (transfer step). For example, the first and second wing portions W1 and W2 may each be divided into multiple portions (divided layers) aligned in a second direction D2 perpendicular to the first direction D1. In this case, the first functional layer K1 may be located on one divided layer, and the second functional layer K2 may be located on another divided layer.

[0041] Figure 17 is a plan view showing an example of a manufacturing method for this optical communication substrate. As shown in Figure 17, the width of the first wing portion W1 and the width of the second wing portion W2 are equal, and the second gap G2 may be larger than the first gap G1. In this case, when the first and second functional layers K1 and K2 are formed, the indium concentration incorporated into the second functional layer K2 will be higher than that of the first functional layer K1. As a result, when the first functional layer K1 and the second functional layer K2 are formed in the same process, the working wavelength band of the first functional layer K1 can be made shorter compared to the second functional layer K2. Since photodetectors tend to have shorter wavelengths than light-emitting elements, in order to bring the wavelengths of the light-emitting and photodetectors closer together, the first functional layer K1 can be made into a light-emitting layer H and the second functional layer K2 into a photodetector layer J.

[0042] The technology described in Figures 7 and 17 allows for the simultaneous formation of multiple semiconductor layers on the same substrate with a small number of steps, satisfying at least one of the following conditions: different wing widths and different gap widths. By utilizing the existence of multiple semiconductor layers that satisfy at least one of the following conditions, it becomes possible to simultaneously form multiple functional layers with different indium compositions.

[0043] In the case of a general flat substrate, the indium (In) concentration is uniform within the wafer surface, and it is impossible to control the In concentration for each region. In the present embodiment, a plurality of semiconductor layers (semiconductor pieces) are formed in large numbers on the same substrate (TK), and by changing at least one of the size (for example, the size in the a-axis direction or the m-axis direction) and the gap width of the plurality of semiconductor layers, even when functional layers are simultaneously formed on each of the plurality of semiconductor layers, a plurality of functional layers having different operating peak wavelengths (peak emission wavelength for a light-emitting element, peak light-receiving wavelength for a light-receiving element) can be obtained. Then, by using a semiconductor layer having a short operating peak wavelength for a light-receiving element and a semiconductor layer having a long operating peak wavelength for a light-emitting element, an optical element module with high light utilization efficiency can be obtained even when a plurality of functional layers are simultaneously peeled off and mounted on another drive circuit.

[0044] FIGS. 18 and 19 are flowcharts showing an example of the method for manufacturing the present optical communication substrate. FIG. 20 is a cross-sectional view showing an example of the method for manufacturing the present optical communication substrate. FIG. 21 is a plan view showing an example of the method for manufacturing the present optical communication substrate. In step S15 of FIGS. 2 and 8, steps S11 to S14 shown in FIGS. 18 to 21 may be performed. That is, in step S11, a first lower layer HS including an n-type layer (for example, an n-type nitride semiconductor layer) is formed on the first wing portion W1, and a second lower layer JS including an n-type layer (for example, an n-type nitride semiconductor layer) is formed on the second wing portion W2. In step S12, a first active layer HM is formed on the first lower layer HS, and a second active layer JM is formed on the second lower layer JS. In step S13, a first upper layer HT including a p-type layer (for example, a p-type nitride semiconductor layer) is formed on the first active layer HM, and a second upper layer JT including a p-type layer (for example, a p-type nitride semiconductor layer) is formed on the second active layer JM. In step S14, a p-electrode HP on the first upper layer HT, an n-electrode HN on the first lower layer HS, a p-electrode JP on the second upper layer JT, and an n-electrode JN on the second lower layer JS are formed.

[0045] Thereby, a first functional layer K1 including a first lower layer HS including an n-type semiconductor layer, a first active layer HM, a first upper layer HT, a p-electrode HP and an n-electrode HN is formed, and a second functional layer K2 including a second lower layer JS including an n-type semiconductor layer, a second active layer JM, a second upper layer JT, a p-electrode JP and an n-electrode JN is formed.

[0046] As shown in FIG. 19, step S11 may include step SE of forming a layer common to the first lower layer HS and the second lower layer JS using the same material under the same conditions. All layers included in the first lower layer HS and all layers included in the second lower layer JS may be common. After step SE, a predetermined treatment (impurity doping, annealing, plasma treatment, etc.) may be performed on the common layer of the first lower layer HS or the common layer of the second lower layer JS.

[0047] Step S12 may include step SF of forming a layer common to the first active layer HM and the second active layer JM using the same material under the same conditions. All layers included in the first active layer HM and all layers included in the second active layer JM may be common. After step SF, a predetermined treatment (impurity doping, annealing, plasma treatment, etc.) may be performed on the common layer of the first active layer HM or the common layer of the second active layer JM.

[0048] Step S13 may include step SG of forming a layer common to the first upper layer HT and the second upper layer JT using the same material under the same conditions. All layers included in the first upper layer HT and all layers included in the second upper layer JT may be common. After step SG, a predetermined treatment (impurity doping, annealing, plasma treatment, etc.) may be performed on the common layer of the first upper layer HT or the common layer of the second upper layer JT.

[0049] As shown in FIG. 19, before step SE, a step of forming a layer unique to the first lower layer HS may be performed. Before step SE, a step of forming a layer unique to the second lower layer JS may be performed. Between step SE and step SF, a step of forming a layer unique to the first lower layer HS or a layer unique to the first active layer HM may be performed. Between step SE and step SF, a step of forming a layer unique to the second lower layer JS or a layer unique to the second active layer JM may be performed.

[0050] Between steps SF and SG, a step may be performed to form a layer specific to the first active layer HM or a layer specific to the first upper layer HT. Between steps SF and SG, a step may be performed to form a layer specific to the second active layer JM or a layer specific to the second upper layer JT. After step SG, a step may be performed to form a layer specific to the first upper layer HS. After step SG, a step may be performed to form a layer specific to the second upper layer JS.

[0051] As shown in Figure 21, in the first functional layer K1, the first lower layer HS and the n electrode HN (cathode) may be in contact, and the first upper layer HT and the p electrode HP (anode) may be in contact. In the second functional layer K2, the second lower layer JS and the n electrode JN may be in contact, and the second upper layer JT and the p electrode JP may be in contact. The second functional layer K2 may be a photodiode in which electrons generated in the second active layer JM by light reception are extracted to the outside via the second lower layer JS and the n electrode JN. The mounting substrate MK of the optical communication substrate EK may include a sensing circuit that detects the flow of electrons from the n electrode JN of the light-receiving element layer J to the mounting substrate MK.

[0052] The emission wavelength range of the first functional layer K1 and the light-receiving wavelength range of the second functional layer K2 may be 420 nm to 480 nm. In this way, even if the layer configuration (layer structure and composition) of the nitride semiconductor (GaN-based semiconductor) is common to the first functional layer K1 and the first photodetector layer, the emission wavelength of the first functional layer K1 and the light-receiving wavelength of the second functional layer K2 can be matched.

[0053] In Figures 18 to 21, the first active layer HM and the second active layer JM include a quantum well layer (MQW), and the number of quantum wells in the first active layer HM and the second active layer JM may be equal. The second active layer JM may have more quantum wells than the first active layer HM. The second active layer JM may have a higher indium (In) concentration than the first active layer HM. The p electrode JP of the second functional layer K2 may have a larger area than the p electrode HP of the first functional layer K1. The n electrode JN of the second functional layer K2 may have a larger area than the n electrode HN of the first functional layer K1.

[0054] If the number of quantum well layers is the same, the functional layers can be deposited simultaneously on the first and second wing sections W1 and W2. If they are different, for example, the second wing section can be masked (using a protective film such as SiN) and the first functional layer K1 can be deposited only on the first wing section W1. Then, the semiconductor substrate can be removed from the deposition furnace, the mask on the second wing section W2 can be removed, and the first wing section W1 can be masked to form the second functional layer K2 only on the second wing section W2. In this way, it is possible to form quantum well layers with different configurations on the first wing section W1 and the second wing section W2.

[0055] The p-electrode region of the light-emitting element layer H may be smaller than the p-electrode region of the photodetector layer J. In this case, a higher current density can be achieved in the light-emitting element layer H with a lower current value. When a c-plane GaN-based light-emitting element is fabricated, driving the light-emitting element HY with a high current density reduces the QCSE (Quantum Confined Stark Effect) present in the active layer HM, increasing the carrier recombination rate and enabling operation in high-frequency bands. By increasing the p-electrode area of ​​the photodetector layer J, holes generated by receiving light from the light-emitting element layer H can be effectively captured within the active layer JM, thereby improving the light-receiving efficiency. In this way, by setting the relationship between the electrode area (area of ​​the functional region) of the light-emitting element layer H and the photodetector layer Y, a highly efficient communication module can be realized.

[0056] If the emission wavelength range of the first functional layer K1 is longer wavelength than the light-receiving wavelength range of the second functional layer K2 (i.e., the emission wavelength range and the light-receiving wavelength range are misaligned), the emission wavelength range and the light-receiving wavelength range can be superimposed by, for example, making the indium concentration of the second active layer JM greater than the indium concentration of the first active layer HM. For example, the area of ​​the second active layer JM can be made smaller than the area of ​​the first active layer HM (for example, by making the width in the first direction smaller), thereby making the indium concentration of the second active layer JM greater than the indium concentration of the first active layer HM. For this purpose, the width of the second wing portion W2 may be smaller than that of the first wing portion W1.

[0057] Figures 22 to 27 are plan views showing examples of the configuration of the light-emitting element layer (first functional layer) and the photodetector layer (second functional layer). As shown in Figures 22 and 23 and Figures 25 and 26, in the first functional layer K1, the p electrode HP (anode) and the n electrode HN (cathode) may be arranged in the second direction D2 (m-axis direction of the first wing portion W1), and in the second functional layer K2, the p electrode JP and the n electrode JN may be arranged in the second direction D2 (m-axis direction of the second wing portion W2). In this case, as shown in Figures 22 and 25, the p electrode HP of the light-emitting element layer H and the p electrode JP of the photodetector layer J may be arranged in the first direction D1, and the n electrode HN of the light-emitting element layer H and the n electrode JN of the photodetector layer J may be arranged in the first direction D1.

[0058] As shown in Figures 23 and 26, the p electrode HP of the light-emitting layer H and the p electrode JP of the photodetector layer J may be aligned in an oblique direction with respect to the first direction D1, and the n electrode HN of the light-emitting layer H and the n electrode JN of the photodetector layer J may also be aligned in an oblique direction with respect to the first direction D1. As shown in Figures 24 and 27, in the first functional layer K1, the p electrode HP (anode) and the n electrode HN (cathode) may be aligned in the first direction D1 (a-axis direction of the first wing portion W1), and in the second functional layer K2, the p electrode JP and the n electrode JN may be aligned in the first direction D1 (a-axis direction of the second wing portion W2).

[0059] As shown in Figures 22 to 24, the p electrodes HP and JP and the n electrodes HN and JN may be rectangular. As shown in Figures 25 to 27, the p electrodes HP and JP and the n electrodes HN and JN may be circular. The light-emitting region of the light-emitting element layer H may be circular, and the light-receiving region of the light-receiving element layer J may be circular.

[0060] Figures 28 and 29 are cross-sectional views showing an example of a method for manufacturing this semiconductor substrate. As shown in Figure 28, the growth of two crystal layers extending in opposite directions from the base X1 along the first direction D1 may be stopped by a stop wall WS to form a second wing portion W2 that is shorter than the first wing.

[0061] As shown in Figure 29, a crosslinked layer GK may be formed by associating two crystal layers that grow from adjacent seed portions S and extend toward each other along the first direction D1, and then etching a predetermined portion UG of the crosslinked layer GK to form the first wing portion W1 or the second wing portion W2.

[0062] Figure 30 is a cross-sectional view showing an example of a method for manufacturing the optical communication substrate. As shown in Figure 30, the method may include a step of forming a texture structure including protrusions 33 on the lower surface of at least one of the first wing portion W1 and the second wing portion W2. In the optical element substrate DK, the lower surface of the first wing portion W1 may have a plurality of protrusions 33, while the lower surface of the second wing portion W2 may not have protrusions. In the optical communication substrate EK obtained after transfer, the lower surface of the light-emitting portion HY may have a plurality of protrusions 33, while the lower surface of the light-receiving portion JY may not have protrusions. The lower surfaces of the light-emitting portion HY and the light-receiving portion JY may each have a plurality of protrusions 33.

[0063] When a textured structure is formed that overlaps with the light-emitting element layer H in a plan view, the light generated in the active layer HM is effectively extracted to the outside of the light-emitting element layer H by the textured structure, thus improving the extraction efficiency of the light-emitting element HY. On the other hand, when a textured structure is formed that overlaps with the photodetector layer J in a plan view, the light that is effectively scattered by the textured structure is incident on the active layer JM, so the amount of light incident at an angle increases. Since the active layer JM is basically thin, about 10 nm to 100 nm or less, the optical path length in the active layer JM is longer for light incident at an angle than for light incident perpendicularly to the active layer JM, thus improving the light absorption efficiency.

[0064] Figure 31 is a cross-sectional view showing an example of a method for manufacturing this optical communication substrate. In Figure 4 and other figures, a gap GD is located between the first and second wing portions W1 and W2 and the mask portion 5 (the first and second wing portions W1 and W2 are floating from the crystal growth substrate TK), but the method is not limited to this. As shown in Figure 31, the first and second wing portions W1 and W2 may be in contact with the mask portion 5. Even in this case, since there is no crystalline bond between the first and second wing portions W1 and W2 and the mask portion 5, the first and second wing portions W1 and W2 can be easily peeled off.

[0065] Figure 32 is a cross-sectional view showing an example of a method for manufacturing this optical communication substrate. In Figure 4 and other figures, the crystal growth substrate TK includes a mask pattern 6, but is not limited to this. As shown in Figure 32, by modifying the pattern of the underlayer 3, a modified region DA (growth suppression region, non-seed pattern) and an unmodified region SA (seed pattern including the first and second seed portions S1 and S2) can be formed. In Figure 32, a coating 7 (growth suppression film) may be formed on the side surface of the lower part (raised portion) of the base X1. An encapsulation film (growth suppression film) may be formed inside the lower part (raised portion) of the base X1.

[0066] For example, a resist film deposited on the seed layer 3 can be patterned, and the exposed seed material can be surface-modified in the irradiated area by, for example, plasma, thereby forming a modified region DA. Specific examples of plasma include argon plasma, oxygen plasma, nitrogen plasma, hydrogen plasma, or a mixture thereof. In Figure 32, the unmodified region SA (seed pattern) may be aluminum nitride, and the modified region DA (unseed pattern) may be aluminum oxynitride.

[0067] Figure 33 is a flowchart showing an example of a method for manufacturing an optical communication device. Figure 34 is a cross-sectional view showing an example of a method for manufacturing an optical communication device. As shown in Figures 33 and 34, the method for manufacturing this optical communication device includes a step S35 of preparing a first optical communication substrate 11 (EK) and a second optical communication substrate 12 (EK), and a step S45 of connecting the first optical communication substrate 11 and the second optical communication substrate 12 to an optical waveguide DL. Through these steps, an optical communication device 30 including the first and second optical communication substrates 11 and 12 and the optical waveguide DL can be obtained. The optical waveguide DL transmits light from the first functional layer K1 of the first optical communication substrate 11 to the second functional layer K2 of the second optical communication substrate 12.

[0068] Figure 35 is a cross-sectional view showing an example of the configuration of this information processing device. As shown in Figure 35, the information processing device 40 can be configured by connecting the first optical communication board 11 of the optical communication device 30 to the processor unit 31 via the interface board IF, and connecting the second optical communication board 12 to the processor unit 32 via the interface board IS.

[0069] The information processing device 40 converts the output data of the processor unit 31 into a light-emitting pattern on the first optical communication board 11, transmits the light-emitting pattern to the second optical communication board 12 via the optical waveguide group LF and converts it back into data, thereby enabling the output data of the processor unit 31 to be input to the processor unit 32. Similarly, the output data of the processor unit 32 is converted into a light-emitting pattern on the second optical communication board 12, transmits the light-emitting pattern to the first optical communication board 11 via the optical waveguide group LF and converts it back into data, thereby enabling the output data of the processor unit 32 to be input to the processor unit 31. This makes high-speed bidirectional communication between the processor units 31 and 32 possible.

[0070] Figure 36 is a flowchart showing an example of a method for manufacturing an optical communication substrate. Figures 37 and 38 are cross-sectional views showing an example of a method for manufacturing an optical communication substrate. As shown in Figures 36 to 38, in this method for manufacturing an optical communication substrate, after step S15 in Figure 2, step S23 is performed to connect the optical element substrate DK to the mounting substrate MK. Through these steps, an optical communication substrate EK can be obtained, comprising a semiconductor substrate 10, an element substrate DK including a first functional layer K1 and a second functional layer K2, and a mounting substrate MK connected to the element substrate DK.

[0071] A translucent substrate (for example, a sapphire substrate) can be used for the main substrate 1 in Figure 37. In Figure 38, a hole UH that overlaps with the light-emitting element layer H in a plan view and a hole UJ that overlaps with the photodetector layer J in a plan view are formed on the main substrate 1. In this case, since the holes UH and UJ become light-transmitting holes, the main substrate 1 may be a non-translucent substrate (for example, a silicon substrate).

[0072] Figure 39 is a block diagram showing an example configuration of the optical element substrate manufacturing apparatus. As shown in Figure 39, the optical element substrate manufacturing apparatus 60 comprises an apparatus M5 that performs process S5 in Figure 2, an apparatus M15 that performs process S15, and a control device MX that controls apparatus M5 and apparatus M15. Apparatus M15 may include a MOCVD apparatus.

[0073] Figure 40 is a block diagram showing an example configuration of the optical communication substrate manufacturing apparatus. As shown in Figure 40, the optical communication substrate manufacturing apparatus 70 comprises an apparatus M5 that performs process S5 in Figure 8, an apparatus M15 that performs process S15, an apparatus M25 that performs process S25, and a control device MX that controls apparatus M5, apparatus M15, and apparatus M25. Apparatus M15 may include a MOCVD apparatus.

[0074] [Examples] As the main substrate 1, a silicon substrate, a silicon carbide substrate (4H-SiC, 6H-SiC substrate), a sapphire substrate, a nitride substrate (GaN, AlN substrate, etc.), a ScMgAlO substrate, etc. can be used.

[0075] The seed patterns P1 and P2 (including the first and second seed portions S1 and S2) may be GaN, AlN, AlGaN, AlInN, AlGaInN, or Al, etc., formed at a low temperature (500°C or below). The thickness of the first and second seed portions S1 and S2 is, for example, 10 nm to 500 nm.

[0076] In the examples, an AlN film (seed layer) was deposited on top of a sapphire or silicon substrate, which served as the main substrate, using a sputtering method. By using sputtering methods such as parallel plate sputtering, magnetron sputtering, or pulsed sputtering, low-temperature and low-cost film deposition is possible. Alternatively, a highly crystalline AlN film may be formed using the MOCVD method.

[0077] A buffer layer may be formed between the main substrate 1 and the seed patterns P1 and P2 (e.g., nitride semiconductor layers). The buffer layer improves the crystallinity and flatness of the seed patterns P1 and P2. The buffer layer may be planar or shaped to match the seed pattern 4 (e.g., stripe-shaped). As the buffer layer, a GaN layer, AlN layer, AlGaN layer, AlInN layer, AlGaInN, Al, etc., formed at a low temperature (below 500°C) may be used. The thickness of the buffer layer is, for example, about 10 nm to 500 nm.

[0078] The mask pattern 6 (including the mask portion 5) is formed on the main substrate 1 using a material that suppresses the longitudinal growth of nitride semiconductors and enables lateral growth. The material of the mask pattern 6 may be silicon nitride, silicon carbide, silicon carbonitride, diamond-like carbon, silicon oxide, or silicon oxynitride. The material of the mask pattern 6 may be a silicon-free component. The material of the mask pattern 6 may be titanium nitride, molybdenum nitride, tungsten nitride, or tantalum carbide. The material of the mask pattern 6 may be a high-melting-point metal. For example, high-melting-point metals include molybdenum, tungsten, or platinum. The mask pattern 6 may be a single layer film made of one of these materials. The mask pattern 6 may also be a multilayer film made by combining multiple of these materials. The thickness of the mask portion 5 is, for example, 5 nm to 2 μm.

[0079] The semiconductor layer L is formed on the crystal growth substrate TK using a MOCVD apparatus. In this embodiment, the semiconductor layer L is a GaN layer, the growth temperature is 1000-1200 degrees Celsius, the V / III ratio is 500-20000, and the growth pressure is 50 kPa. To make the semiconductor layer L n-type, SiH ４ You can dope by flushing it. I'll deliberately use SiH ４ Even without introducing it, a material containing Si can be used in the mask pattern 6, for example, SiO ２ Alternatively, by using SiN, it is possible to perform Si doping with the Si evaporated from it.

[0080] It is preferable to set the film deposition conditions in at least two stages. In the first stage, the film deposition temperature is set to about 1030°C and V / III is set to about 2000 to form growth nuclei (vertical growth portions) of the first semiconductor layer L1 on the first seed portion S1 and growth nuclei (vertical growth portions) of the second semiconductor layer L2 on the second seed portion S2 (see Figure 13). The thickness (height) of the growth nuclei is set to about 0.2 to 3.0 μm, and its width may be about the same as the width of the ridge portion R (width of the first seed portion S1) or slightly exceeding in the a-axis direction (second direction). In the second stage, the film deposition temperature is raised to about 100°C to grow (stretch) the first and second wing portions W1 and W2 (GaN layers) from the growth nuclei in the lateral direction (a-axis direction). Here, growth is stopped when the gap width between the wing portions growing in opposite directions on the void GD reaches a specified value, and a semiconductor substrate 10 is obtained.

[0081] A GaN-based semiconductor layer of the first functional layer K1 (first lower layer HS, first active layer HM, and first upper layer HT) and a GaN-based semiconductor layer of the second functional layer K2 (second lower layer JS, second active layer JM, and second upper layer JT) were deposited on the semiconductor substrate 10 using the same process, and each of the resulting GaN-based semiconductor layers was patterned.

[0082] Specifically, the first and second lower layers HS and JS were formed in the following order: an n-type GaN layer, an n-type AlGaN layer, a superlattice layer of GaN and InGaN layers, and a non-doped GaN layer (all layers of the first and second lower layers were common). The first and second active layers HM and JM were formed as a multi-quantum well layer of InGaN layers (well layer) and GaN layers (barrier layer) (all layers of the first and second active layers were common). The first and second upper layers HT and JT were formed in the following order: a p-type AlGaN layer, a p-type GaN layer (low-concentration Mg doped), and a p-type GaN layer (high-concentration Mg doped) (all layers of the first and second upper layers were common). As a result, the emission wavelength range of the first functional layer K1 and the light-receiving wavelength range of the second functional layer K2 could be superimposed (for example, 420 to 480 nm).

[0083] After forming an insulating film IS covering the sides of the GaN-based semiconductor layers of the first and second functional layers K1 and K2, the p-electrode HP and n-electrode HN of the first functional layer K1 and the p-electrode JP and n-electrode JN of the second functional layer K2 were formed using a metal film to obtain the optical element substrate DK. For example, the metal layer is a single element, alloy, or multilayer film containing at least one of Al, Ti, Sn, Au, Ag, Cu, Mg, Mo, Pt, and In.

[0084] The electrode material may be a metal oxide (indium tin oxide, indium zinc oxide, etc.). The materials of p-electrode HP, n-electrode HN, p-electrode JP, and n-electrode JN can be common, but are not limited to this. p-electrode HP and p-electrode JP may be made of different materials. n-electrode HN and n-electrode JN may be made of different materials. p-electrode HP and n-electrode HN may be made of different materials. p-electrode JP and n-electrode JN may be made of different materials.

[0085] Furthermore, multiple light-emitting layers H (including the first functional layer K1) and multiple first photodetector layers J (including the second functional layer K2) were transferred from the optical element substrate DK to the same mounting substrate MK to obtain an optical communication substrate EK (light-emitting and photodetector substrate). For example, by rupturing the bases (tether portions TZ) of the first and second wing portions W1 and W2 while the first and second functional layers K1 and K2 are connected to the mounting substrate via a conductive layer (solder layer, anisotropic conductive layer, etc.), the light-emitting portion (light-emitting body) HY, which includes a part of the first wing portion W1 and the first functional layer K1, and the photodetector portion (photodetector) JY, which includes a part of the second wing portion W2 and the second functional layer K2, can be transferred to the mounting substrate MK (e.g., ASIC). When rupturing the tether portion TZ, ultrasonic vibration may be applied to at least one of the optical element substrate DK and the mounting substrate MK.

[0086] (Note) The above disclosure is for illustrative and explanatory purposes only, and not for limitation. Based on these examples and descriptions, many variations will be obvious to those skilled in the art, and these variations are also included in the embodiments.

[0087] Disclosure 1: A method for manufacturing an optical element substrate, comprising: preparing a semiconductor substrate comprising: a main substrate; a first seed pattern including a first seed portion; a second seed pattern including a second seed portion; a first semiconductor layer bonded to the first seed portion and containing a nitride semiconductor; and a second semiconductor layer bonded to the second seed portion and containing a nitride semiconductor, wherein the first seed pattern and the second seed pattern are arranged above the main substrate along a first direction; the first seed portion and the second seed portion have a longitudinal direction in a second direction perpendicular to the first direction; the first semiconductor layer has a first base portion extending upward from the first seed portion and a first wing portion extending from the first base portion in the first direction; and the second semiconductor layer has a second base portion extending upward from the second seed portion and a second wing portion extending from the second base portion in the first direction; and forming a first functional layer located on the first semiconductor layer and having a light-emitting function; and a second functional layer located on the second semiconductor layer and having a light-receiving function.

[0088] Disclosure 2: The method for manufacturing an optical element substrate according to Disclosure 1, comprising the steps of forming a third functional layer located on the third semiconductor layer and having a light-emitting function, and a fourth functional layer located on the fourth semiconductor layer and having a light-receiving function. The semiconductor substrate comprises a third semiconductor layer bonded to the third seed portion and containing a nitride semiconductor, and a fourth semiconductor layer bonded to the fourth seed portion and containing a nitride semiconductor, the third semiconductor layer having a third base portion extending upward from the third seed portion and a third wing portion extending in the first direction from the third base portion, and the fourth semiconductor layer having a fourth base portion extending upward from the fourth seed portion and a fourth wing portion extending in the first direction from the fourth base portion.

[0089] Disclosure Item 3: A method for manufacturing an optical element substrate according to Disclosure Item 2, wherein the spacing between the first seed portion and the third seed portion is different from the spacing between the second seed portion and the fourth seed portion.

[0090] Disclosure Item 4: A method for manufacturing an optical element substrate according to Disclosure Item 2, wherein the distance between the first seed portion and the third seed portion is greater than the distance between the second seed portion and the fourth seed portion.

[0091] Disclosure Item 5: The method for manufacturing an optical element substrate according to Disclosure Item 4, wherein the spacing between the first seed portion and the third seed portion is approximately an integer multiple of the spacing between the second seed portion and the fourth seed portion.

[0092] Disclosure Item 6: A method for manufacturing an optical element substrate according to any one of Disclosure Items 2 to 4, wherein the first semiconductor layer and the third semiconductor layer are adjacent to each other with a first gap between them, and the second semiconductor layer and the fourth semiconductor layer are adjacent to each other with a second gap between them.

[0093] Disclosure Item 7: A method for manufacturing an optical element substrate according to any one of Disclosure Items 1 to 6, wherein the width of the first wing portion in the first direction is greater than the width of the second wing portion in the first direction.

[0094] Disclosure Item 8: A method for manufacturing an optical element substrate according to any one of Disclosure Items 2 to 6, wherein the width of the third wing portion in the first direction is greater than the width of the fourth wing portion in the first direction.

[0095] Disclosure Item 9: A method for manufacturing an optical element substrate according to Disclosure Item 6, wherein the first gap is smaller than the second gap.

[0096] Disclosure Item 10: A method for manufacturing an optical element substrate according to any one of Disclosure Items 1 to 9, wherein the through-dislocation density of the first wing portion is 1 / 5 or less of the through-dislocation density of the first base portion.

[0097] Disclosure Item 11: A method for manufacturing an optical element substrate according to any one of Disclosure Items 1 to 10, wherein the first direction is the a-axis direction of the nitride semiconductor.

[0098] Disclosure Item 12: A method for manufacturing an optical element substrate according to any one of disclosure items 1 to 11, wherein the second direction is the m-axis direction of the nitride semiconductor.

[0099] Disclosure Item 13: A method for manufacturing an optical element substrate according to any one of Disclosure Items 1 to 12, wherein the semiconductor substrate has light-emitting regions including the first seed pattern and photodetector regions including the second seed pattern arranged alternately in a first direction.

[0100] Disclosure Item 14: A method for manufacturing an optical device substrate according to any one of disclosure items 1 to 13, wherein the semiconductor substrate comprises the main substrate and a crystal growth substrate including the first and second seed patterns, and the first wing portion and the second wing portion each face the crystal growth substrate with a gap between them.

[0101] Disclosure Item 15: A method for manufacturing an optical element substrate according to any one of Disclosure Items 1 to 14, wherein the light-emitting function is a function as a light-emitting diode or laser diode, and the light-receiving function is a function as a photodiode.

[0102] Disclosure Item 16: A method for manufacturing an optical element substrate according to any one of disclosure items 1 to 15, wherein the first functional layer includes a first electrode, and the second functional layer includes a second electrode having a longer length in the first direction than the first electrode.

[0103] Disclosure Item 17: A method for manufacturing an optical device substrate according to any one of disclosure items 1 to 16, wherein the first functional layer includes a first active layer, and the second functional layer includes a second active layer having a higher indium concentration than the first active layer.

[0104] Disclosure Item 18: A method for manufacturing an optical element substrate according to any one of Disclosure Items 1 to 17, wherein the widths of the first seed portion and the second seed portion in the first direction are equal.

[0105] Disclosure Item 19: A method for manufacturing an optical element substrate according to any one of Disclosure Items 1 to 17, wherein the width of the first seed portion in the first direction is greater than the width of the second seed portion in the first direction.

[0106] Disclosure Item 20: A method for manufacturing an optical element substrate according to any one of Disclosure Items 1 to 19, wherein the main substrate is a different type of substrate with a different lattice constant from the nitride semiconductor.

[0107] Disclosure Item 21: An optical communication substrate from which a light-emitting element including at least a portion of the first semiconductor layer and the first functional layer, and a photodetector including at least a portion of the second semiconductor layer and the second functional layer are transferred, from an optical element substrate manufactured by any one of the manufacturing methods described in Disclosure Items 1 to 20.

[0108] Disclosure Item 22: An optical communication device comprising an optical communication substrate as described in Disclosure Item 21 and an optical waveguide connected to the optical communication substrate.

[0109] Disclosure Item 23: An optical element substrate comprising: a main substrate; a first seed pattern including a first seed portion and a second seed pattern including a second seed portion; a first semiconductor layer bonded to the first seed portion and containing a nitride semiconductor; a second semiconductor layer bonded to the second seed portion and containing a nitride semiconductor; a first functional layer located on the first semiconductor layer; and a second functional layer located on the second semiconductor layer, wherein the first semiconductor layer includes a first base portion extending upward from the first seed portion and a first wing portion extending in a first direction from the first base portion; the second semiconductor layer includes a second base portion extending upward from the second seed portion and a second wing portion extending in a first direction from the second base portion; the first seed portion and the second seed portion have a longitudinal direction in a second direction perpendicular to the first direction; the first functional layer is a light-emitting element layer; and the second functional layer is a light-receiving element layer.

[0110] Disclosure Item 24: The optical element substrate according to Disclosure Item 23, wherein the first seed pattern includes a third seed portion adjacent to the first seed portion, the second seed pattern includes a fourth seed portion adjacent to the second seed portion, a third semiconductor layer bonded to the third seed portion and containing a nitride semiconductor, a fourth semiconductor layer bonded to the fourth seed portion and containing a nitride semiconductor, a third functional layer located on the third semiconductor layer, and a fourth functional layer located on the fourth semiconductor layer, the third semiconductor layer includes a third base portion extending upward from the third seed portion and a third wing portion extending in a first direction from the third base portion, the second semiconductor layer includes a fourth base portion extending upward from the fourth seed portion and a fourth wing portion extending in a first direction from the fourth base portion, the third seed portion and the fourth seed portion have the second direction as their longitudinal direction, the third functional layer is a light-emitting element layer, and the fourth functional layer is a light-receiving element layer.

[0111] Disclosure Item 25: The optical element substrate according to Disclosure Item 24, wherein the spacing between the first seed portion and the third seed portion is different from the spacing between the second seed portion and the fourth seed portion.

[0112] Disclosure Item 26: The optical element substrate according to Disclosure Item 25, wherein the distance between the first seed portion and the third seed portion is greater than the distance between the second seed portion and the fourth seed portion.

[0113] Disclosure Item 27: The optical element substrate according to any one of Disclosure Items 24 to 26, wherein the first semiconductor layer and the third semiconductor layer are adjacent to each other with a first gap between them, and the second semiconductor layer and the fourth semiconductor layer are adjacent to each other with a second gap between them.

[0114] Disclosure Item 28: The optical element substrate according to any one of disclosure items 23 to 27, wherein the width of the first wing portion in the first direction is greater than the width of the second wing portion in the first direction.

[0115] Disclosure Item 29: The optical element substrate according to any one of Disclosure Items 24 to 27, wherein the width of the third wing portion in the first direction is greater than the width of the fourth wing portion in the first direction.

[0116] Disclosure 30: The optical element substrate according to Disclosure 27, wherein the first gap is smaller than the second gap.

[0117] Disclosure Item 31: The optical element substrate according to any one of disclosure items 23 to 30, wherein the width of the first seed portion in the first direction is greater than the width of the second seed portion in the first direction.

[0118] Disclosure Item 32: A step of preparing an optical element substrate comprising: a main substrate; a first seed pattern including a first seed portion; a second seed pattern including a second seed portion; a first semiconductor layer bonded to the first seed portion and containing a nitride semiconductor; a second semiconductor layer bonded to the second seed portion and containing a nitride semiconductor; a first functional layer located on the first semiconductor layer; and a second functional layer located on the second semiconductor layer, wherein the first semiconductor layer includes a first base portion extending upward from the first seed portion and a first wing portion extending in a first direction from the first base portion; the second semiconductor layer includes a second base portion extending upward from the second seed portion and a second wing portion extending in a first direction from the second base portion; the first seed portion and the second seed portion have a longitudinal direction in a second direction perpendicular to the first direction; the first functional layer is a light-emitting element layer; and the second functional layer is a light-receiving element layer. A method for manufacturing an optical communication substrate, comprising the step of transferring the first functional layer and the second functional layer from the optical element substrate to a mounting substrate.

[0119] Disclosure 33: A method for manufacturing an optical communication substrate according to disclosure 32, comprising transferring a light-emitting element including at least a portion of the first semiconductor layer and a first functional layer, and a photodetector including at least a portion of the second semiconductor layer and a second functional layer, from the main substrate and a crystal growth substrate including the first seed pattern and the second seed pattern, onto the mounting substrate.

[0120] 1 Main substrate 4 Seed pattern 5 Mask section 6 Mask pattern 10 Semiconductor substrate 30 Optical communication device 40 Information processing device 60 Optical element substrate manufacturing equipment 70 Optical communication device manufacturing equipment L1-L4 First to fourth semiconductor layers W1-W4 First to fourth wing sections K1-K4 First to fourth functional layers P1 First seed pattern P2 Second seed pattern S1 First seed section S2 Second seed section DK Optical element substrate EK Optical communication substrate MK Mounting substrate H Light-emitting element layer J Photodetector layer TK Crystal growth substrate

Claims

1. A method for manufacturing an optical element substrate, comprising the steps of: preparing a semiconductor substrate comprising a main substrate, a first seed pattern including a first seed portion, a second seed pattern including a second seed portion, a first semiconductor layer bonded to the first seed portion and containing a nitride semiconductor, and a second semiconductor layer bonded to the second seed portion and containing a nitride semiconductor, wherein the first seed pattern and the second seed pattern are arranged above the main substrate along a first direction, the first seed portion and the second seed portion have a longitudinal direction in a second direction perpendicular to the first direction, the first semiconductor layer has a first base portion extending upward from the first seed portion and a first wing portion extending from the first base portion in the first direction, and the second semiconductor layer has a second base portion extending upward from the second seed portion and a second wing portion extending from the second base portion in the first direction; and forming a first functional layer located on the first semiconductor layer and having a light-emitting function, and a second functional layer located on the second semiconductor layer and having a light-receiving function.

2. The method for manufacturing an optical element substrate according to claim 1, comprising the steps of forming a third seed portion adjacent to the first seed portion, a fourth seed portion adjacent to the second seed portion, the third seed portion and the fourth seed portion having the second direction as their longitudinal direction, the semiconductor substrate comprising a third semiconductor layer bonded to the third seed portion and containing a nitride semiconductor, and a fourth semiconductor layer bonded to the fourth seed portion and containing a nitride semiconductor, the third semiconductor layer having a third base portion extending upward from the third seed portion and a third wing portion extending in the first direction from the third base portion, the fourth semiconductor layer having a fourth base portion extending upward from the fourth seed portion and a fourth wing portion extending in the first direction from the fourth base portion, and forming a third functional layer located on the third semiconductor layer and having a light-emitting function, and a fourth functional layer located on the fourth semiconductor layer and having a light-receiving function.

3. The method for manufacturing an optical element substrate according to claim 2, wherein the spacing between the first seed portion and the third seed portion is different from the spacing between the second seed portion and the fourth seed portion.

4. The method for manufacturing an optical element substrate according to claim 2, wherein the distance between the first seed portion and the third seed portion is greater than the distance between the second seed portion and the fourth seed portion.

5. The method for manufacturing an optical element substrate according to claim 4, wherein the spacing between the first seed portion and the third seed portion is approximately an integer multiple of the spacing between the second seed portion and the fourth seed portion.

6. A method for manufacturing an optical element substrate according to any one of claims 2 to 4, wherein the first semiconductor layer and the third semiconductor layer are adjacent to each other with a first gap between them, and the second semiconductor layer and the fourth semiconductor layer are adjacent to each other with a second gap between them.

7. The method for manufacturing an optical element substrate according to any one of claims 1 to 6, wherein the width of the first wing portion in the first direction is greater than the width of the second wing portion in the first direction.

8. The method for manufacturing an optical element substrate according to any one of claims 2 to 6, wherein the width of the third wing portion in the first direction is greater than the width of the fourth wing portion in the first direction.

9. The method for manufacturing an optical element substrate according to claim 6, wherein the first gap is smaller than the second gap.

10. The method for manufacturing an optical element substrate according to any one of claims 1 to 9, wherein the penetration dislocation density of the first wing portion is 1 / 5 or less of the penetration dislocation density of the first base portion.

11. The method for manufacturing an optical element substrate according to any one of claims 1 to 10, wherein the first direction is the a-axis direction of the nitride semiconductor.

12. The method for manufacturing an optical element substrate according to any one of claims 1 to 11, wherein the second direction is the m-axis direction of the nitride semiconductor.

13. The method for manufacturing an optical element substrate according to any one of claims 1 to 12, wherein the semiconductor substrate has light-emitting regions including the first seed pattern and photodetector regions including the second seed pattern arranged alternately in a first direction.

14. The method for manufacturing an optical element substrate according to any one of claims 1 to 13, wherein the semiconductor substrate comprises the main substrate and a crystal growth substrate including the first seed pattern and the second seed pattern, and the first wing portion and the second wing portion each face the crystal growth substrate with a gap between them.

15. A method for manufacturing an optical element substrate according to any one of claims 1 to 14, wherein the light-emitting function is a function as a light-emitting diode or laser diode, and the light-receiving function is a function as a photodiode.

16. A method for manufacturing an optical element substrate according to any one of claims 1 to 15, wherein the first functional layer includes a first electrode, and the second functional layer includes a second electrode having a longer length in the first direction than the first electrode.

17. A method for manufacturing an optical element substrate according to any one of claims 1 to 16, wherein the first functional layer includes a first active layer, and the second functional layer includes a second active layer having a higher indium concentration than the first active layer.

18. A method for manufacturing an optical element substrate according to any one of claims 1 to 17, wherein the widths of the first seed portion and the second seed portion in the first direction are equal.

19. The method for manufacturing an optical element substrate according to any one of claims 1 to 17, wherein the width of the first seed portion in the first direction is greater than the width of the second seed portion in the first direction.

20. The method for manufacturing an optical element substrate according to any one of claims 1 to 19, wherein the main substrate is a different type of substrate with a different lattice constant from the nitride semiconductor.

21. An optical communication substrate on which a light-emitting element including at least a portion of the first semiconductor layer and the first functional layer, and a light-receiving element including at least a portion of the second semiconductor layer and the second functional layer are transferred from an optical element substrate obtained by the manufacturing method described in any one of claims 1 to 20.

22. An optical communication device comprising an optical communication substrate as described in claim 21 and an optical waveguide connected to the optical communication substrate.

23. An optical element substrate comprising: a main substrate; a first seed pattern including a first seed portion and a second seed pattern including a second seed portion; a first semiconductor layer bonded to the first seed portion and containing a nitride semiconductor; a second semiconductor layer bonded to the second seed portion and containing a nitride semiconductor; a first functional layer located on the first semiconductor layer; and a second functional layer located on the second semiconductor layer, wherein the first semiconductor layer includes a first base portion extending upward from the first seed portion and a first wing portion extending in a first direction from the first base portion; the second semiconductor layer includes a second base portion extending upward from the second seed portion and a second wing portion extending in a first direction from the second base portion; the first seed portion and the second seed portion have a longitudinal direction in a second direction perpendicular to the first direction; the first functional layer is a light-emitting element layer; and the second functional layer is a light-receiving element layer.

24. The optical element substrate according to claim 23, wherein the first seed pattern includes a third seed portion adjacent to the first seed portion, the second seed pattern includes a fourth seed portion adjacent to the second seed portion, the third semiconductor layer bonded to the third seed portion and containing a nitride semiconductor, the fourth semiconductor layer bonded to the fourth seed portion and containing a nitride semiconductor, the third functional layer located on the third semiconductor layer, and the fourth functional layer located on the fourth semiconductor layer, the third semiconductor layer includes a third base portion extending upward from the third seed portion and a third wing portion extending in a first direction from the third base portion, the second semiconductor layer includes a fourth base portion extending upward from the fourth seed portion and a fourth wing portion extending in a first direction from the fourth base portion, the third seed portion and the fourth seed portion have the second direction as their longitudinal direction, the third functional layer is a light-emitting element layer, and the fourth functional layer is a light-receiving element layer.

25. The optical element substrate according to claim 24, wherein the spacing between the first seed portion and the third seed portion is different from the spacing between the second seed portion and the fourth seed portion.

26. The optical element substrate according to claim 25, wherein the distance between the first seed portion and the third seed portion is greater than the distance between the second seed portion and the fourth seed portion.

27. The optical element substrate according to any one of claims 24 to 26, wherein the first semiconductor layer and the third semiconductor layer are adjacent to each other with a first gap between them, and the second semiconductor layer and the fourth semiconductor layer are adjacent to each other with a second gap between them.

28. The optical element substrate according to any one of claims 23 to 27, wherein the width of the first wing portion in the first direction is greater than the width of the second wing portion in the first direction.

29. The optical element substrate according to any one of claims 24 to 27, wherein the width of the third wing portion in the first direction is greater than the width of the fourth wing portion in the first direction.

30. The optical element substrate according to claim 27, wherein the first gap is smaller than the second gap.

31. The optical element substrate according to any one of claims 23 to 30, wherein the width of the first seed portion in the first direction is greater than the width of the second seed portion in the first direction.

32. A step of preparing an optical element substrate comprising: a main substrate; a first seed pattern including a first seed portion; a second seed pattern including a second seed portion; a first semiconductor layer bonded to the first seed portion and containing a nitride semiconductor; a second semiconductor layer bonded to the second seed portion and containing a nitride semiconductor; a first functional layer located on the first semiconductor layer; and a second functional layer located on the second semiconductor layer, wherein the first semiconductor layer includes a first base portion extending upward from the first seed portion and a first wing portion extending in a first direction from the first base portion; the second semiconductor layer includes a second base portion extending upward from the second seed portion and a second wing portion extending in a first direction from the second base portion; the first seed portion and the second seed portion have a longitudinal direction in a second direction perpendicular to the first direction; the first functional layer is a light-emitting element layer; and the second functional layer is a light-receiving element layer. A method for manufacturing an optical communication substrate, comprising the step of transferring the first functional layer and the second functional layer from the optical element substrate to a mounting substrate.

33. A method for manufacturing an optical communication substrate according to claim 32, comprising transferring a light-emitting element including at least a portion of the first semiconductor layer and a first functional layer, and a photodetector including at least a portion of the second semiconductor layer and a second functional layer, from the main substrate and a crystal growth substrate including the first seed pattern and the second seed pattern to the mounting substrate.

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