Semiconductor device and method for producing a semiconductor device

Abstract

A method for producing a semiconductor device (1) comprises applying a getter layer (3) over a sapphire substrate (2). The getter layer (3) is formed from a compound semiconductor material comprising Al, N and a transition metal X. High-temperature heating of the getter layer (3) is then carried out at a temperature of greater than 1400°C and less than 2400°C.

Description

[0001] 2024PF01113 1

[0002] Semiconductor Device and Method for Manufacturing a Semiconductor Device

[0003] DESCRIPTION

[0004] The present disclosure relates to a semiconductor device and a method for manufacturing such a semiconductor device. In particular, the present disclosure relates to the use of a getter layer made of a compound semiconductor material containing aluminum, nitrogen, and a transition metal on a sapphire substrate.

[0005] Such semiconductor devices are suitable as substrates or templates for the epitaxial growth of layers containing, for example, (Al)GaN or InGaN. Due to their large bandgap, semiconductor devices with GaN or InGaN layers are used in numerous applications, including optoelectronic devices.

[0006] One purpose of the present disclosure is to provide an improved manufacturing process and improved semiconductor devices.

[0007] According to the implementation forms, the problem is solved by the subject matter of the independent patent claims. Advantageous further developments are defined in the dependent claims.

[0008] The problem is solved in particular by a method for fabricating a semiconductor device, which includes the deposition of a getter layer over a sapphire substrate. This getter layer is formed from a compound semiconductor material comprising aluminum (Al), nitrogen (N), and a transition metal X. Subsequently, a high-temperature 2024PF01113 2

[0009] Temperature heating of the sapphire substrate with the getter layer at a temperature greater than 1400°C and less than 2400°C.

[0010] A compound semiconductor material is a semiconductor material composed of two or more elements. In this case, the compound semiconductor material comprises aluminum, nitrogen, and a transition metal X. The transition metal X could be, for example, scandium (Sc), yttrium (Y), titanium (Ti), or hafnium (Hf).

[0011] A getter layer has the effect of binding unwanted impurities, such as oxygen, thereby improving the purity and quality of the layers above it. As a result, a subsequent process for removing the impurities, for example in a later epitaxy procedure, can be omitted.

[0012] By incorporating a getter layer containing Al, N, and X, the formation of so-called AlON volcanoes—that is, Al10N accumulations that grow from the sapphire / Al interface to the surface—can be prevented. This allows the high-temperature heating process to be carried out at higher temperatures, resulting in a lower dislocation density. A lower dislocation density is advantageous because it increases the internal quantum efficiency in optoelectronic devices such as UV LEDs.

[0013] The function of the getter layer also includes effectively preventing or reducing oxygen diffusion by introducing a transition metal X, thereby preventing or at least reducing the formation of AlON contamination on the surface. This simplifies the downstream epitaxy process and improves the crystal quality of subsequent layers. 2024PF01113 3

[0014] Furthermore, by using X and controlling the concentration of X in a layer of A1XN, a lattice fitting can be achieved, which advantageously reduces relaxations and thus allows for better performance characteristics of the components.

[0015] In the context of this disclosure, high-temperature heating is a process in which the material is heated to very high temperatures. It is therefore a heating of the semiconductor device or layer sequence at very high temperatures in the range of 1400°C to 2400°C. It can also be referred to as high-temperature annealing or simply annealing. High-temperature heating can be carried out in a furnace. Advantageously, it serves to improve the crystal structure of the material and reduce defects. High-temperature heating is performed, for example, at a temperature higher than that at which a downstream sputtering or epitaxial deposition process is carried out.

[0016] One advantage of the process is therefore improved crystal quality of the fabricated semiconductor device. Another advantage is the potential for lattice matching to subsequent layers, such as AlGaN, which can improve the performance of the semiconductor device.

[0017] According to one implementation, the thickness of the getter layer is in the range of 20 nm to 400 nm, for example in a range of 50 nm to 300 nm.

[0018] In one implementation of the process, high-temperature heating takes place at a temperature of 1400°C to 1800°C. This temperature range is advantageous because it provides good Ba-2024PF01113 4

[0019] lance offers a balance between minimizing defects and maintaining the structural integrity of the sapphire substrate and the getter layer applied to it.

[0020] According to one execution method, after high-temperature heating of the sapphire substrate with the getter layer, a semiconductor body is epitaxially grown over the getter layer, which has an lUxAlyGai-x-yN layer, where 0 < x < 1 and 0 < y < Igilt .

[0021] The lUxAlyGai-x-yN layer is a compound semiconductor layer composed of the elements indium (In), aluminum (Al), gallium (Ga), and nitrogen (N). The variables x and y determine the specific composition of the layer, which in turn influences the optoelectronic properties such as band gap and emission wavelength.

[0022] The term "epitactical" refers to the controlled growth of a crystalline layer on a substrate, where the crystalline structure of the layer is influenced by the structure of the underlying substrate. In particular, at least one crystallographic orientation of the growing crystal corresponds to an orientation of the crystalline substrate.

[0023] According to one implementation method, during the fabrication of a semiconductor device, the amount of transition metal X contained in the getter layer is selected according to the lattice constant of the semiconductor body. This means that the concentration of the transition metal X in the getter layer is specifically adjusted so that the resulting crystal structure of the getter layer optimally matches the lattice constant of the subsequently deposited semiconductor body. By adjusting the amount of X in the getter layer, 2024PF01113 5

[0024] The lattice matching between the getter layer and the semiconductor body is improved, leading to a reduction in lattice mismatches and associated defects.

[0025] Furthermore, the targeted selection of the amount of X can also help to suppress oxygen diffusion from the sapphire substrate by having the transition metal act as an oxygen getter. This prevents the formation of unwanted A10N contamination, which could negatively affect surface quality and subsequent epitaxial growth processes. Advantageously, this can lead to improved quantum efficiency and quality of the produced semiconductor devices, which is of particular importance for applications in optoelectronics and power electronics.

[0026] According to an implementation form, a method for manufacturing a semiconductor device is described in which a transition metal X is selected from a group comprising scandium (Sc), yttrium (Y), titanium (Ti) and hafnium (Hf).

[0027] The specific selection of X from Sc, Y, Ti, and Hf offers advantages. These transition metals, due to their high electronegativity, contribute to the inhibition of oxygen diffusion that could occur from the sapphire substrate into the getter layer and further into the layers above. This is particularly important to prevent the formation of A10N contamination, which could impair the crystal quality of subsequent layers. Furthermore, the inclusion of these transition metals enables better lattice matching of the getter layer to subsequent layers, especially to AlGaN layers typically used in UV LEDs. This lattice matching is crucial to ensure optimal performance.

[0028] To minimize stress relaxations and defect formation caused by grid mismatches.

[0029] The selection of Sc, Y, Ti and Hf as the transition metal X in the getter layer advantageously leads to improved control over oxygen diffusion, better lattice matching and a reduction in dislocation density, which supports a higher quality of the manufactured semiconductor device.

[0030] Following a specific design, an AIN layer is applied to the sapphire substrate before the getter layer is applied. This AIN layer can be applied to the sapphire substrate using various methods, such as sputtering.

[0031] An AIN layer is a semiconductor layer made of aluminum (Al) and nitrogen (N).

[0032] According to one embodiment, the method comprises an initial high-temperature heating of the sapphire substrate with the AIN layer at a temperature greater than 1400°C and less than 2400°C, for example at a temperature in a range between 1400°C and 1800°C, before the getter layer is applied.

[0033] Heating stabilizes the AIN layer and reduces potential stresses that could arise from lattice mismatch between the sapphire substrate and the AIN layer. This leads to improved crystal quality of the AIN layer, which in turn forms the basis for the subsequent getter layer. The getter layer, consisting of a compound semiconductor with aluminum, nitrogen, and a transition metal X, is then deposited onto the already heat-treated AIN layer. Advantageously, da-2024PF01113 7

[0034] achieved through improved quality of the semiconductor device.

[0035] In the context of this disclosure, an initial high-temperature heating is a heating process performed prior to the high-temperature heating of the getter layer. It can be carried out at the same temperatures as the subsequent high-temperature heating of the getter layer. For example, the initial high-temperature heating is performed at a temperature higher than that at which a downstream sputtering or epitaxial process is carried out.

[0036] Alternatively, the sapphire substrate with the AIN layer is not initially heated to a high temperature. The AIN layer is heated to a high temperature together with the getter layer, for example.

[0037] According to the implementation, in a process for manufacturing a semiconductor device, an additional layer of aluminium nitride (AlN) is applied after a getter layer has been applied to a sapphire substrate, but before the sapphire substrate with the getter layer is subjected to high-temperature heating.

[0038] If an initial high-temperature heating process is also carried out, the application of an AIN layer as well as the application of the getter layer takes place after the initial high-temperature heating.

[0039] According to possible implementation methods, after the application of the getter layer and before the high-temperature heating of the sapphire substrate with the getter layer, an AIN layer is applied and immediately-2024PF01113 8

[0040] A lattice matching layer comprising Al, N and a transition metal X is subsequently applied.

[0041] This involves applying a layer sequence A1XN / A1N / A1XN. According to the implementation methods, a layer sequence A1XN / ALN / ALXN is applied to a previously annealed AIN layer, i.e., an AIN layer that has already been subjected to initial high-temperature heating.

[0042] The use of a layer sequence A1XN / ALN / ALXN, consisting of a getter layer, an AIN layer, and a lattice-matching layer, allows for the suppression of oxygen diffusion, particularly through the getter layer, as well as achieving a particularly precise lattice match with subsequent AlGaN or InGaN layers, especially through the lattice-matching layer. The composition of the two AIXN layers, i.e., the getter layer and the lattice-matching layer, can differ. They can therefore contain different amounts of X. This allows for largely lattice-matched growth of the AlGaN or InGaN layers.x A-lyGax-x-yN layers, where 0 < x < 1 and 0 < y < 1, are achieved in the following structure.

[0043] Another aspect of the invention relates to a semiconductor device comprising a sapphire substrate, an AIN layer adjacent to the sapphire substrate, and a getter layer arranged on the side of the AIN layer facing away from the sapphire substrate. This getter layer contains aluminum (Al), nitrogen (N), and a transition metal X. An advantage of this structure is the inhibition of oxygen diffusion from the sapphire substrate, which can prevent the formation of AlON contamination and thus improve the crystal quality of subsequent layers. Another advantage is the possible lattice matching by the getter layer to subsequent layers.

[0044] AlGaN layers, or InxAlyGax-x-yN layers, where 0 < x < 1 and 0 < y < 1, can improve the performance of the semiconductor device. The concentration of the transition metal X can be varied to specifically adapt to the requirements of subsequent layers. A semiconductor device based on this approach can be used as a lattice-matched substrate for subsequent epitaxial growth processes for LED structures.

[0045] According to one implementation, the thickness of the getter layer is in the range of 20 nm to 400 nm, for example in a range of 50 nm to 300 nm.

[0046] The transition metal X can be selected from the elements scandium (Sc), yttrium (Y), titanium (Ti), and hafnium (Hf). The advantages of these elements described herein can lead to an improvement in the overall performance and reliability of the semiconductor device.

[0047] Firstly, the use of a transition metal with high electronegativity ensures oxygen trapping, and secondly, the lattice structure can be adapted to subsequent layers by using a certain concentration of X. This advantageously reduces defects and improves the performance of the components.

[0048] According to one embodiment, the semiconductor device has a getter layer with a dislocation density of less than 5 IO. 8 cm" 2 exhibits. If further semiconductor layers are epitaxially grown above the getter layer, a high quality of these semiconductor layers can be achieved even at such low dislocation densities. 2024PF01113 10

[0049] According to one embodiment, the semiconductor device comprises a semiconductor body featuring an epitaxially grown compound semiconductor layer consisting of an indium-aluminum-aluminum-x-yn layer with 0 < x and 0 < y, which is of the n-type. The indium-aluminum-aluminum-x-yn compound semiconductor layer offers flexibility in adjusting the band gap and material properties by varying the indium (In), aluminum (Al), and gallium (Ga) content, for example, AlGaN or InGaN.

[0050] Furthermore, the semiconductor body includes a photoactive zone for absorbing or emitting electromagnetic radiation.

[0051] In the context of this disclosure, a photoactive zone can be composed of several sublayers and, for example, form a multiple quantum well (MQW) structure. The photoactive zone, in the context of this disclosure, is capable of emitting or absorbing electromagnetic radiation, for example, converting electrical energy into the emission of electromagnetic radiation. Additionally, the semiconductor body comprises a p-type semiconductor layer.

[0052] The layers in the semiconductor body are arranged, for example, in such a way that the epitaxially grown n-type compound semiconductor layer is located between the photoactive zone and the sapphire substrate.

[0053] Another aspect of the invention relates to a semiconductor device comprising a sapphire substrate and a getter layer adjacent to this sapphire substrate. This getter layer contains the elements nitrogen (N), aluminum (Al), and a transition metal X. An enrichment region of the getter layer adjacent to the sapphire substrate contains an An-2024PF01113 11

[0054] Oxygen enrichment occurs in such a way that A10XN is formed. Thus, an enrichment zone forms in the getter layer, in an area bordering the sapphire substrate, and exhibits oxygen enrichment, leading to the formation of A10XN.

[0055] An enrichment region in which A10XN is formed exists, for example, when the oxygen concentration in this region is at least 20%. This oxygen concentration can be detected, for example, using a TEM (transmission electron microscope), EDA (energy-dispersive X-ray analysis), or SIMS (secondary ion mass spectrometry) method.

[0056] One advantage of this structure is the improved crystal quality of the subsequent layers, which can lead to higher efficiency of the semiconductor device. Another advantage is the ability to improve the lattice matching to subsequent layers, such as AlGaN, by selecting the appropriate amount of transition metal X in the getter layer. This can enhance the performance of optoelectronic devices, such as LEDs.

[0057] The enrichment area of ​​the getter layer can have a layer thickness of a maximum of 400 nm, for example in a range of 50 nm to 400 nm.

[0058] According to the embodiment of the semiconductor device, an AIN layer is arranged adjacent to the getter layer on the side of the getter layer facing away from the sapphire substrate. According to the embodiment, the AIN layer can act as a buffer layer for LED growth. 2024PF01113 12

[0059] According to the embodiments, the semiconductor device comprises a compound semiconductor layer of InxAlyGax-x-yN, where 0 < x and 0 < y. This compound semiconductor layer is arranged on the side of the getter layer facing away from the substrate.

[0060] Advantageously, the lattice alignment can be chosen such that both an AlGaN and an InGaN compound semiconductor layer are possible. The crystal structure can therefore be adapted to subsequent AlGaN or InGaN layers, depending on the application.

[0061] According to the implementation forms, the semiconductor device comprises a photoactive zone for absorbing or emitting electromagnetic radiation and a p-type semiconductor layer.

[0062] Depending on the implementation form, the semiconductor device is designed as an optoelectronic semiconductor device, such as a light-emitting diode (LED), or as a power semiconductor device.

[0063] Furthermore, the use of A1XN allows the fabrication of grid-matched substrates on AlGaN or other compound semiconductors. This reduces relaxation at defects and enables better performance of semiconductor devices, such as LEDs.

[0064] FROM LEADERSHIP EXAMPLE LE

[0065] The accompanying drawings serve to illustrate exemplary embodiments of the invention. The drawings depict these embodiments and, together with the description, serve to explain them. Further exemplary embodiments and many of the intended advantages will become apparent from the detailed description below. The elements and structures shown in the drawings are not not-2024PF01113 13

[0066] They must be shown to scale with each other. Identical reference symbols refer to identical or corresponding elements and structures.

[0067] The figures show:

[0068] Fig. 1: a semiconductor device produced by the method described herein, in which a getter layer is arranged on a sapphire substrate; Fig. 2: a semiconductor device with an AIN layer on the getter layer.

[0069] Fig. 3: a semiconductor device with two AIN layers, between which the getter layer is arranged; Fig. 4: a semiconductor device with an AIN layer adjacent to the substrate.

[0070] Fig. 5: a semiconductor device with an AIN layer that has already undergone initial high-temperature heating and another AIN layer; Fig. 6: a semiconductor device with an AIN layer that has already undergone initial high-temperature heating and another AIN layer and a separate grid matching layer.

[0071] Fig. 7A: a semiconductor device with an AIN layer, wherein the semiconductor device is designed as an optoelectronic semiconductor device,

[0072] Fig. 7B : a semiconductor device with an AIN layer, wherein the semiconductor device is designed as a power semiconductor device,

[0073] Fig. 8A: a semiconductor device with an enhancement layer, wherein the semiconductor device is configured as an optoelectronic semiconductor device, Fig. 8B: a semiconductor device with an enhancement layer, wherein the semiconductor device is configured as a power semiconductor device, 2024PF01113 14

[0074] Fig. 9: a method for producing a semiconductor device in which high-temperature heating takes place; Fig. 10: a method for producing a semiconductor device in which an AIN layer is applied before high-temperature heating.

[0075] Fig. 11 : a method for producing a semiconductor device in which an initial high-temperature heating takes place before the high-temperature heating of the getter layer .

[0076] The following detailed description refers to the accompanying drawings, which form part of the disclosure and show specific embodiments for illustrative purposes. In this context, directional terminology such as "top," "bottom," "front," "back," "over," "on," "in front," "behind," "front," "back," etc., refers to the orientation of the figures just described. Since the components of the embodiments can be positioned in different orientations, the directional terminology serves only for explanation and is in no way restrictive.

[0077] The description of the embodiments is not restrictive, as other embodiments exist and structural or logical modifications can be made without deviating from the scope defined by the claims. In particular, elements of the embodiments described below can be combined with elements of other described embodiments, unless otherwise indicated by the context.

[0078] The terms "wafer" or "semiconductor substrate" used in the following description can encompass any semiconductor-based structure that has a semiconductor surface. Wafer and structure are to be understood as do-2024PF01113 15

[0079] This includes doped and undoped semiconductors, epitaxial semiconductor layers, optionally supported by a substrate, and other semiconductor structures. For example, a layer of a first semiconductor material may have grown on a growth substrate of a second semiconductor material, such as a GaAs substrate, a GaN substrate, or a Si substrate, or of an insulating material, such as on a sapphire substrate.

[0080] Depending on the intended use, the semiconductor can be based on a direct or an indirect semiconductor material. Examples of semiconductor materials particularly suitable for generating electromagnetic radiation include, in particular, nitride semiconductor compounds, which can generate, for example, ultraviolet, blue, or longer-wavelength light, such as GaN, InGaN, AIN, AlGaN, AlGalnN, and AlGalnBN. The stoichiometric ratio of the compound semiconductor materials can vary.

[0081] The term "substrate" generally includes insulating, conductive or semiconductor substrates.

[0082] In the context of the present revelation, a “sapphire substrate” is a substrate which contains sapphire, i.e., A12O3.

[0083] Fig. 1 shows a cross-sectional view of a semiconductor device 1 according to embodiments, comprising a sapphire substrate 2 and a getter layer 3 arranged thereon. The getter layer 3 consists of a compound semiconductor material containing aluminum (Al), nitrogen (N), and a transition metal (X). The getter layer material can, for example, have a composition of Ali_ z X z The transition metal X can be, for example, scandium (Sc), yttrium (Y), titanium (Ti), or hafnium (Hf). 2024PF01113 16

[0084] In getter layer 3, z can be greater than 0 and less than 0.2.

[0085] The getter layer 3 used can be very thin, with a thickness in the range of 20 nm to 400 nm, for example, in the range of 50 nm to 300 nm. The getter layer 3 serves to prevent oxygen diffusion from the sapphire substrate 2. Furthermore, it enables lattice matching to subsequently epitaxially grown layers. The getter layer 3 can be applied, for example, by sputtering.

[0086] The concentration of X can vary locally and, for example, decrease or increase from bottom to top, or assume different discrete values, for example 0-100% relative to the maximum X content z, in different areas, for example with different thicknesses.

[0087] After applying the getter layer 3, high-temperature heating can be carried out, for example at a temperature greater than 1400°C and less than 2400°C.

[0088] As a result, an enrichment region 8 can form between the sapphire substrate 2 and the getter layer 3. This enrichment region 8 contains, in addition to the elements Al, N, and a transition metal X, an enrichment with oxygen, so that A1OXN is formed. This enrichment region 8 has a thickness 9 of a maximum of 400 nm, for example, a maximum of 300 nm.

[0089] Fig. 2 shows a cross-sectional view of a semiconductor device 1 according to further embodiments, in which an additional AIN layer 4 is deposited on the getter layer 3. The getter layer 3 also consists of a compound semiconductor containing aluminum (Al), nitrogen (N), and a transition metal (X). 2024PF01113 17

[0090] The transition metal X can be, for example, scandium (Sc), yttrium (Y), titanium (Ti), or hafnium (Hf). The concentration of X in getter layer 3 can be up to 20%. The getter layer 3 used can be very thin, with a thickness in the range of 20 nm to 400 nm, for example, in the range of 50 nm to 300 nm.

[0091] The A1N layer 4 is located on the side of the getter layer 3 facing away from the sapphire substrate 2. The A1N layer 4 can be deposited by sputtering. The A1N layer 4 can, for example, have a thickness of 200 nm to 400 nm.

[0092] After applying the getter layer 3 and the AIN layer 4, high-temperature heating can be carried out, for example at a temperature greater than 1400°C and less than 2400°C.

[0093] As a result, an enrichment region 8 can form between the sapphire substrate 2 and the getter layer 3. This enrichment region 8 contains, in addition to the elements Al, N, and a transition metal X, an enrichment with oxygen, so that A1OXN is formed. This enrichment region 8 has a thickness 9 of a maximum of 400 nm, for example, a maximum of 300 nm.

[0094] Due to the presence of getter layer 3, oxygen diffusion from the sapphire substrate 2 into the AIN layer 4 can be suppressed. As a result, the formation of Al ON contamination on the surface of the AIN layer 4 can be reduced or suppressed.

[0095] Fig. 3 shows a semiconductor device 1 which has a sapphire substrate 2 on which a layer structure is deposited. This structure comprises a lower AIN layer 4, a middle getter layer 3 and an upper AIN layer 4. The getter-2024PF01113 18

[0096] Layer 3 contains aluminum (Al), nitrogen (N), and a transition metal X, and is embedded between the two AIN layers 4. The getter layer 3 used can be very thin, with a thickness in the range of 20 nm to 400 nm, for example, in the range of 50 nm to 300 nm. For example, the lower AIN layer 4, the middle getter layer 3, and the upper AIN layer 4 could have been deposited by sputtering.

[0097] The choice of transition metal X can vary depending on specific requirements; for example, yttrium or scandium are possible, but other metals such as titanium or hafnium can also be chosen. The concentration of X in the getter layer can be up to 20%.

[0098] After applying the layer structure over the sapphire substrate 2, high-temperature heating is carried out, for example at a temperature greater than 1400°C and less than 2400°C.

[0099] This arrangement serves to prevent oxygen diffusion by having getter layer 3 act as an oxygen getter and thus prevent or at least reduce the formation of AlON contamination. The composition of getter layer 3, made of A1XN, can vary to ensure optimal lattice fit and crystal quality.

[0100] The advantage of arranging the two AIN layers 4 with the intervening getter layer 3 is that it enables good crystal quality for the entire semiconductor device 1. As a result, semiconductor layers with a lower dislocation density can subsequently be epitaxially grown.

[0101] Fig. 4 shows a semiconductor device 1 in which an AIN layer 4 is applied to the sapphire substrate 2, which is 2024PF01113 19

[0102] The AIN layer can be applied by sputtering. For example, the AIN layer can have a thickness of 200 nm to 400 nm. This AIN layer 4 is directly followed by the getter layer 3. The getter layer 3 contains aluminum (Al), nitrogen (N), and a transition metal X and serves to prevent or at least reduce oxygen diffusion and subsequently improve the crystal quality of the grown semiconductor layers.

[0103] The choice of transition metal X can vary depending on specific requirements; for example, yttrium or scandium can be chosen, but other metals such as titanium or hafnium are also possible. The getter layer 3 can be very thin, with a thickness in the range of 20 nm to 400 nm, for example, 50 nm to 300 nm.

[0104] After applying the layer structure over the sapphire substrate 2, high-temperature heating is carried out, for example at a temperature greater than 1400°C and less than 2400°C.

[0105] The arrangement shown in Fig. 4 offers a simple structure that nevertheless effectively controls oxygen diffusion and enables lattice matching to subsequent AlGaN layers or other epitaxially grown layers. This embodiment can be particularly advantageous when lower layer complexity is desired without compromising functionality. As a result, subsequent semiconductor layers with a lower dislocation density can be epitaxially grown.

[0106] Fig. 5 shows a semiconductor device comprising a sapphire substrate 2, an AIN layer 4, a getter layer 3, and another AIN layer 4. An AIN layer 4 is deposited on the sapphire substrate 2 by sputtering. 2024PF01113 20

[0107] can have a thickness of, for example, 200 nm to 400 nm. The AIN layer 4 can be applied directly to the sapphire substrate 2.

[0108] The getter layer 3, deposited on the AIN layer 4, consists of a compound semiconductor containing aluminum (Al), nitrogen (N), and a transition metal (X). The transition metal X can be scandium (Sc), yttrium (Y), titanium (Ti), or hafnium (Hf). The getter layer 3 can have a thickness of 20 nm to 400 nm, for example, 50 nm to 300 nm, and the concentration of X can be up to 20%.

[0109] Above the getter layer 3 is another AIN layer 4, which can also be applied by sputtering.

[0110] In the fabrication of the semiconductor device 1 shown in Fig. 5, after the application of the AIN layer 4 and before the application of the getter layer 3 and the further AIN layer 4, a high-temperature heating process is carried out, for example at a temperature greater than 1400°C and less than 2400°C. This high-temperature heating is also referred to as initial high-temperature heating within the scope of this disclosure.

[0111] Subsequently, the getter layer 3 and the further AIN layer 4 are applied. The entire semiconductor device 1 shown is then heated to a high temperature again. This results in layers 5 that have been heated to a high temperature once and layers 6 that have been heated to a high temperature twice. The layers 6 that have been heated to a high temperature twice consist of the sapphire substrate 2 and the directly adjacent AIN layer 4, which have already undergone initial high-temperature heating. The further AIN layer 4, which was applied after the getter layer 3, can have a greater thickness than the 2024PF01113 21

[0112] The first AIN layer 4 is present. As a result of the two high-temperature heating processes, the semiconductor device 1 can exhibit better crystal quality, which can improve the quality of subsequently deposited semiconductor layers.

[0113] Fig. 6 shows a semiconductor device 1 comprising a sapphire substrate 2, an AIN layer 4, a getter layer 3 and a lattice matching layer 7 .

[0114] A first AIN layer 4, which can be deposited by sputtering and has a thickness of 200 nm to 400 nm, is arranged on the sapphire substrate 2. This layer was subjected to initial high-temperature heating prior to the deposition of the getter layer 3 and the subsequent AIN layer 4. A getter layer 3, consisting of a compound semiconductor containing aluminum (Al), nitrogen (N), and a transition metal (X), is arranged on the first AIN layer 4. The transition metal X can be scandium (Sc), yttrium (Y), titanium (Ti), or hafnium (Hf). The getter layer 3 can have a thickness of 20 nm to 400 nm, for example, 50 nm to 300 nm, and the concentration of X can be up to 20%.

[0115] Above the getter layer 3 is another AIN layer 4, which can also be applied by sputtering.

[0116] Above the AIN layer 4, a lattice matching layer 7 can be arranged, which, like the getter layer 3, can consist of a compound semiconductor containing aluminum Al, nitrogen N and a transition metal X (Ali_ z X z N) . The concentration z of the transition metal X, which can be selected independently of the chosen transition metal in the getter layer from scandium Sc, yttrium Y, titanium Ti or hafnium Hf, can, for example, be a maximum of 20%. The selection of the concentration can be chosen as follows: 2024PF01113 22

[0117] This ensures that a lattice fit to subsequent layers is achieved. The concentration of the transition metal in the lattice-fitting layer 7 can differ from the concentration of the transition metal in the getter layer 3.

[0118] In the manufacture of the semiconductor device 1 shown in Fig. 6, after the application of the AIN layer 4 and before the application of the getter layer 3 and the further AIN layer 4 as well as the lattice matching layer 7, high-temperature heating is carried out, for example at a temperature greater than 1400°C and less than 2400°C.

[0119] Following this initial high-temperature heating, a getter layer 3, another AIN layer 4, and a lattice-matching layer 7 are deposited. The entire semiconductor device 1 shown can then be heated to a high temperature again. This results in layers 5 that have been heated to a high temperature only once and layers 6 that have been heated to a high temperature twice. The layers 6 that have been heated to a high temperature twice can include the sapphire substrate 2 and the directly adjacent AIN layer 4, which have already undergone initial high-temperature heating. The layers 5 that have been heated to a high temperature only once can include the getter layer 3, the AIN layer 4, and the lattice-matching layer 7.

[0120] As a result of the two high-temperature heating processes, the semiconductor device 1 exhibits improved crystal quality, which in turn enhances the quality of subsequently deposited semiconductor layers. Furthermore, the presence of the lattice-matching layer 7 enables largely lattice-matched growth of the subsequent AlGaN layers. 2024PF01113 23

[0121] Fig. 7A shows a semiconductor device 1 which, in addition to the layers shown in Fig. 6, has further epitaxially grown semiconductor layers 10, 11, 12. For example, a first semiconductor layer 10 of a first conductivity type, for example n-type, a photoactive zone 11, and a second semiconductor layer 12 of a second conductivity type, for example p-type, can be arranged over the once high-temperature heated layers 5. The semiconductor layers can be compound semiconductor layers. For example, the first and / or the second semiconductor layer 10, 12 can be formed as an IUxAlyGai-x-yN layer with 0 < x < 1, 0 < y < , for example made of AlGaN or InGaN. The photoactive zone 11 can, for example, be configured to generate or absorb electromagnetic radiation.The semiconductor device 1 can further comprise a first contact element 21 for electrically contacting the first semiconductor layer 10. The semiconductor device 1 can also comprise a second contact element 22 for electrically contacting the second semiconductor layer 12. When a suitable voltage is applied between the first contact element 21 and the second contact element 22, holes and electrons, for example, in the region of the photoactive zone 11 can recombine with each other, emitting electromagnetic radiation 26. The generated electromagnetic radiation 26 can, for example, be emitted via a surface of the second or the first semiconductor layer 12, 10.

[0122] The semiconductor device 1 shown in Fig. 7A can be an optoelectronic semiconductor device 19 and can be configured to emit or absorb electromagnetic radiation 26.

[0123] The semiconductor device 1 shown in Fig. 7B can, in addition to the layers shown in Fig. 6, include a semiconductor layer 2024PF01113 24

[0124] 13 exhibit. The semiconductor layer 13 can be described as an InxAlyGax-x- y The N-layer can be formed with 0 < x < 1, 0 < y < 1, for example from AlGaN or InGaN. Any circuit elements 25, for example transistors or others, can be formed in the semiconductor layer 13. For example, the transistors can be power transistors. For example, the semiconductor device 1 shown in Fig. 7B can be a power semiconductor device 20. This can be designed for applications in power electronics and be characterized by a capability to handle high currents and high voltages.

[0125] Fig. 8A shows a semiconductor device 1 according to further embodiments, in which, in addition to the layers shown in Fig. 2, further epitaxially grown semiconductor layers, for example a first semiconductor layer 10, a photoactive zone 11 and a second semiconductor layer 12, are arranged, each fulfilling specific functions within the semiconductor device 1. The photoactive zone 11 can, for example, be configured to generate or absorb electromagnetic radiation. Analogous to the semiconductor device 1 shown in Fig. 7A, the semiconductor device 1 can further comprise a first contact element 21 and a second contact element 22.

[0126] The semiconductor device 1 shown in Fig. 8A can be an optoelectronic semiconductor device 19 and can be configured to emit or absorb electromagnetic radiation 26.

[0127] The semiconductor device 1 shown in Fig. 8B can have an additional semiconductor layer 13 besides the layers shown in Fig. 2. The semiconductor layer 13 can be described as an InxAlyGai-x- y N-layer with 0 < x < 1, 0 < y < 1, example-2024PF01113 25

[0128] The semiconductor layer 13 can be made of AlGaN or InGaN. Any circuit elements 25, such as transistors or other components, can be formed in the semiconductor layer 13. For example, the transistors can be power transistors. For example, the semiconductor device 1 shown in Fig. 7B can be a power semiconductor device 20. This can be designed for applications in power electronics and be characterized by a capability to handle high currents and high voltages.

[0129] Fig. 9 shows a method for fabricating a semiconductor device, which is divided into three main steps. First, a getter layer 3 is deposited directly onto a substrate (S13). This getter layer consists of a compound semiconductor containing aluminum (Al), nitrogen (N), and a transition metal (X). The transition metal X can be scandium (Sc), yttrium (Y), titanium (Ti), or hafnium (Hf). After the getter layer is deposited, the layer is heated to a high temperature (S14) to a temperature between 1400°C and 2400°C, for example, between 1400°C and 1700°C. Subsequently, a compound semiconductor layer is epitaxially deposited (S15), growing an InxAlyGax-x-yN layer with 0 < x < 1, 0 < y < 1 on the getter layer. This layer can contain, for example, indium (In), aluminum (Al), gallium (Ga) and nitrogen (N) and can be applied epitaxially.

[0130] Fig. 10 shows a similar process for fabricating a semiconductor device as in Fig. 9, but with an additional step. Before the application of the getter layer S13, an A1N layer is deposited onto the substrate, S16. After the application of the A1N layer, the getter layer S13 is applied, followed by high-temperature heating S14 at a temperature greater than 1400°C and less than 2400°C. Subsequently, an epitaxial compound semiconductor S15 can be deposited.

[0131] layer, which can be applied to the high-temperature heated getter layer.

[0132] The additional AIN layer can further improve the crystal quality of subsequent layers and optimize the performance of the semiconductor device.

[0133] Fig. 11 shows a detailed flowchart of a process for manufacturing a semiconductor device. The process begins with the deposition (S16) of an AIN layer onto a substrate. This is followed by initial temperature heating (S17) at high temperatures in a range between 1400°C and 2400°C.

[0134] After initial heating to temperature, a getter layer (S13) is applied. The getter layer can consist of a compound semiconductor containing aluminum, nitrogen, and a transition metal (X).

[0135] An AIN layer (S16) can be applied. This can be followed by the application of a lattice-fitting layer (S18). The lattice-fitting layer contains aluminum, nitrogen, and a transition metal X. The concentration of X in the lattice-fitting layer can differ from the concentration of X in the getter layer. X can be selected independently from scandium, yttrium, titanium, or hafnium in the getter layer and the lattice-fitting layer. High-temperature heating (14) then takes place at a temperature between 1400 °C and 2400 °C. This high-temperature heating (14) can improve the crystal structure and reduce defects.

[0136] Subsequently, an epitaxial deposition of a compound semiconductor layer S15 can be performed. 2024PF01113 27

[0137] Although specific embodiments have been illustrated and described herein, those skilled in the art will recognize that the specific embodiments shown and described can be replaced by a multitude of alternative and / or equivalent embodiments without departing from the scope of protection of the invention. The application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, the invention is limited only by the claims and their equivalents. 2024PF01113 28

[0138] REFERENCE MARK LIST

[0139] 1 Semiconductor device

[0140] 2 Sapphire substrate

[0141] 3 getter layer

[0142] 4 AIN layer

[0143] 5 uniquely high-temperature heated layers

[0144] 6 double high-temperature heated layers

[0145] 7 Lattice matching layer

[0146] 8 Enrichment area

[0147] 9 Thickness

[0148] 10 first semiconductor layer

[0149] 11 Photoactive Zone

[0150] 12 second semiconductor layer

[0151] 13 Semiconductor layer

[0152] 19 Optoelectronic semiconductor device

[0153] 20 Power semiconductor device

[0154] 21 first contact element

[0155] 22 second contact element

[0156] 25 Circuit element

[0157] 26 electromagnetic radiation

[0158] 513 Applying a getter layer

[0159] 514 High-temperature heating

[0160] 515 Epitaxial deposition of a compound semiconductor layer

[0161] 516 Applying an AIN layer

[0162] 517 Initial temperature heating

[0163] 518 Application of a lattice matching layer

Claims

2024PF01113 29 REQUIREMENTS 1. Method for manufacturing a semiconductor device ( 1 ) , comprising: Deposition (S13) of a getter layer (3) over a sapphire substrate (2) which is formed from a compound semiconductor material comprising Al, N and a transition metal X, and subsequently High-temperature heating (S14 ) of the getter layer (3) at a temperature greater than 1400°C and less than 2400°C .

2. The method according to claim 1, wherein the high-temperature heating (S14) is carried out at a temperature of 1400°C to 1800°C.

3. Method according to claim 1 or 2, wherein after high-temperature heating (S14) a semiconductor body having an InxAlyGai-x-yN layer with 0 < x < 1, 0 < y < 1 is epitaxially grown over the getter layer (3) (S15) .

4. The method of claim 3, wherein an amount of X contained in the getter layer (3) is selected according to the lattice constant of the semiconductor body.

5. Method according to any one of claims 1 to 4, wherein X is selected from Sc, Y, Ti and Hf.

6. Method according to any one of claims 1 to 5, wherein prior to the application (S13) of the getter layer (3) an AIN layer (4) is applied to the sapphire substrate (2) .

7. The method of claim 6, wherein prior to the application (S13) of the getter layer (3) an initial high-temperature heating (S17) of the AIN layer (4) is carried out at a temperature greater than 1400°C and less than 2400°C. 2024PF01113 30 8. Method according to any one of claims 1 to 7, wherein after the application (S 13 ) of the getter layer ( 3 ) and before the high-temperature heating ( 14 ) of the getter layer ( 3 ) an AIN layer ( 4 ) is applied (S 16 ).

9. Method according to any one of claims 1 to 8, wherein after the application (S 13 ) of the getter layer ( 3 ) and before the high-temperature heating (S 14 ) of the getter layer ( 3 ) an application (S 16 ) of an AIN layer ( 4 ) and subsequently an application (S 18 ) of a lattice matching layer ( 7 ) comprising Al , N and a transition metal X, is carried out.

10. Semiconductor device (1) comprising a sapphire substrate (2), an AIN layer (4) adjacent to the sapphire substrate (2), and a getter layer (3) arranged on a side of the AIN layer (4) facing away from the sapphire substrate (2), comprising Al, N, and a transition metal X.

11. Semiconductor device ( 1 ) according to claim 10 , wherein X is selected from Sc, Y, Ti and Hf .

12. Semiconductor device (1) according to claim 10 or 11, wherein the getter layer (3) has a dislocation density of less than 5-10 8 cm- 2 exhibits .

13. Semiconductor device ( 1 ) , according to one of claims 10 to 12 , further comprising a semiconductor body, comprising an epitaxially grown first compound semiconductor layer ( 10 ) of InxAlyGai-x-yN with 0 < x < 1 , 0 < y < 1 .

14. Semiconductor device (1) according to claim 13, wherein the first compound semiconductor layer (10) is of a first conductivity type, further comprising: 2024PF01113 31 a photoactive zone ( 11 ) for absorbing or emitting electromagnetic radiation as well as a second semiconductor layer ( 12 ) of a second conductivity type .

15. Semiconductor device (1) comprising a sapphire substrate (2) , a getter layer (3) adjacent to the sapphire substrate (2) comprising N, Al and a transition metal X, wherein in an enrichment region (8) of the getter layer (3) adjacent to the sapphire substrate (2) an enrichment with oxygen is formed such that A1OXN is formed .

16. Semiconductor device ( 1 ) according to claim 15 , wherein the enrichment area ( 8 ) has a thickness ( 9 ) of a maximum of 400 nm .

17. Semiconductor device ( 1 ) according to claim 15 or 16, wherein an AIN layer ( 4 ) is arranged adjacent to the getter layer ( 3 ) on the side of the getter layer ( 3) facing away from the sapphire substrate ( 2 ).

18. Semiconductor device ( 1 ) according to one of claims 15 to 17 , further comprising an epitaxially grown first compound semiconductor layer ( 10 ) of InxAlyGai-x-yN with 0 < x < 1 , 0 < y < 1 .

19. Semiconductor device ( 1 ) according to any one of claims 15 to 18, further comprising a photoactive zone ( 11 ) for absorbing or emitting electromagnetic radiation as well as a second semiconductor layer ( 12 ) of a second conductivity type .2024PF01113 32 20. Semiconductor device ( 1 ) according to any one of claims 10 to 19, wherein the semiconductor device ( 1 ) is an optoelectronic semiconductor device or a power semiconductor device ( 20 ).

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