Semiconductor device and method for manufacturing the same

Abstract

To provide a manufacturing method of a semiconductor device capable of improving characteristics.SOLUTION: A manufacturing method of a semiconductor device according to an embodiment includes preparing a structure including a silicon carbide member and a first film containing silicon and oxygen laminated on the silicon carbide member. The manufacturing method includes performing a first process of heat-treating the structure in a first atmosphere containing hydrogen. The manufacturing method includes, after the first process, performing a second process of heat-treating the structure in a second atmosphere containing nitrogen and oxygen. The oxygen concentration in the second atmosphere is 5 ppm or more and 1000 ppm or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD Embodiments of the present invention relate to a semiconductor device and a method for manufacturing the semiconductor device. [Background technology]

[0002] There are semiconductor devices such as transistors that use silicon carbide (SiC), and good characteristics are required for semiconductor devices. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-109396 Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE INVENTION An embodiment of the present invention provides a semiconductor device capable of improving characteristics, and a method for manufacturing the semiconductor device. [Means for solving the problem]

[0005] According to an embodiment of the present invention, a method for manufacturing a semiconductor device includes preparing a structure including a silicon carbide member and a first film containing silicon and oxygen stacked on the silicon carbide member. The manufacturing method includes performing a first process of heat-treating the structure in a first atmosphere containing hydrogen. The manufacturing method also includes performing a second process after the first process of heat-treating the structure in a second atmosphere containing nitrogen and oxygen. The concentration of the oxygen in the second atmosphere is 5 ppm or more and 1000 ppm or less. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a flowchart illustrating a method for manufacturing a semiconductor device according to the embodiment. [Figure 2]FIG. 2 is a schematic cross-sectional view illustrating the semiconductor device according to the embodiment. [Figure 3] 3A to 3C are schematic views illustrating the method for manufacturing a semiconductor device according to the embodiment. [Figure 4] 4A to 4C are schematic views illustrating the method for manufacturing a semiconductor device according to the embodiment. [Figure 5] FIG. 5 is a schematic cross-sectional view illustrating the semiconductor device according to the embodiment. [Figure 6] 6(a) and 6(b) are graphs illustrating the characteristics of the semiconductor device. [Figure 7] 7(a) and 7(b) are graphs illustrating the characteristics of the semiconductor device. [Figure 8] 8(a) and 8(b) are graphs illustrating the characteristics of the semiconductor device. [Figure 9] FIG. 9 is a graph illustrating the characteristics of the semiconductor device. [Figure 10] FIG. 10 is a graph illustrating the characteristics of the semiconductor device. [Figure 11] FIG. 11 is a graph illustrating the characteristics of the semiconductor device. [Figure 12] FIG. 12 is a graph illustrating the characteristics of the semiconductor device. [Figure 13] FIG. 13 is a graph illustrating the characteristics of the semiconductor device. [Figure 14] FIG. 14 is a graph illustrating the characteristics of the semiconductor device. [Figure 15] FIG. 15 is a schematic cross-sectional view illustrating the semiconductor device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Furthermore, even when the same part is shown, the dimensions and ratios may be different depending on the drawing. In the present specification and the drawings, elements similar to those described above with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.

[0008] FIG. 1 is a flowchart illustrating a method for manufacturing a semiconductor device according to the embodiment. FIG. 2 is a schematic cross-sectional view illustrating the semiconductor device according to the embodiment. 1, the method for manufacturing a semiconductor device according to the embodiment includes preparing a structure (step S110), a first process (step S120), and a second process (step S130). The method may also include forming a conductive film (step S140), which will be described later.

[0009] 2, in the semiconductor device 110, a first film 10 is provided on a silicon carbide member 50. A structure 10B includes the silicon carbide member 50 and the first film 10. The first film 10 is stacked on the silicon carbide member 50. The silicon carbide member 50 includes silicon carbide (SiC). The silicon carbide member 50 includes, for example, 4H—SiC.

[0010] The first film 10 includes silicon and oxygen. The first film 10 is, for example, a silicon oxide film. For example, the first film 10 is deposited on the silicon carbide member 50. The first film 10 is formed by, for example, chemical vapor deposition (CVD). The chemical vapor deposition may include atomic layer deposition (ALD). The first film 10 may be formed by, for example, a physical vapor deposition (PVD) method. The PVD method includes at least one of evaporation and sputtering. The method for manufacturing a semiconductor device according to the embodiment may further include depositing the first film 10 on the silicon carbide member 50 (one example of step S110).

[0011] The direction from the silicon carbide member 50 toward the first film 10 is defined as the Z-axis direction. For example, the first film 10 contacts the silicon carbide member 50. An interface 15 exists between the silicon carbide member 50 and the first film 10.

[0012] The thickness t1 of the first film 10 (thickness before the first treatment) is, for example, 20 nm or more and 100 nm or less. The thickness t1 is the length along the Z-axis direction. The first film 10 having such a thickness t1 can be used as a gate insulating film of a transistor. With such a thickness t1, appropriate insulating properties, appropriate electrical characteristics (e.g., threshold voltage, etc.), and good reliability can be obtained. The thickness t1 may be 30 nm or more and 60 nm or less.

[0013] The semiconductor device 110 may further include a first conductive film E1. The first conductive film E1 is, for example, a gate electrode. The first and second processes described above are performed before the formation of the first conductive film E1. The semiconductor device 110 includes a structure 10B and the first conductive film E1. The semiconductor device 110 is, for example, a transistor.

[0014] In the first process (step S120), the structure 10B is heat-treated in a first atmosphere containing hydrogen.

[0015] The second process (step S130) is performed after the first process. In the second process, the structure 10B is heat-treated in a second atmosphere containing nitrogen (N2) and oxygen (O2). The second atmosphere contains a trace amount of oxygen. For example, the concentration of oxygen (O2) in the second atmosphere is 5 ppm or more and 1000 ppm or less. This concentration is a volume ratio.

[0016] Such a process results in high carrier mobility in the semiconductor device 110.

[0017] 3A to 3C are schematic views illustrating the method for manufacturing a semiconductor device according to the embodiment. 3 illustrates the change in temperature during the second treatment. The horizontal axis of FIG. 3 represents time tm, and the vertical axis represents temperature Tmp.

[0018] As shown in FIG. 3, in the second treatment, the temperature of the structure 10B is increased from 700°C to 1300°C, then maintained at 1200°C, and then decreased to 700°C or below. As shown in FIG. 3, the time for maintaining the temperature at 1300°C (maximum temperature) is designated as time tx1. The time for maintaining the temperature at 1200°C is designated as time tx2. In one example (first sample), time tx1 is 3 hours, and time tx2 is 5.5 hours. The second atmosphere contains nitrogen (N2) and oxygen (O2). The oxygen concentration (volume ratio) in the second atmosphere is 500 ppm. Furthermore, a first reference example sample is fabricated in which the second atmosphere is nitrogen and substantially does not contain oxygen (concentration less than 0.1 ppm).

[0019] The carrier mobility in the first sample is lower than that in the sample of the first reference example. A sample containing a trace amount of oxygen exhibits higher carrier mobility than a sample not containing oxygen. According to the embodiment, a method for manufacturing a semiconductor device capable of improving characteristics can be provided.

[0020] The high carrier mobility obtained in the sample in an atmosphere containing a trace amount of oxygen is thought to be related to the fact that the heat treatment in the second atmosphere containing a trace amount of oxygen and nitrogen puts the interface 15 between the silicon carbide member 50 and the first film 10 in a good condition.

[0021] For example, a low interface state density and high carrier mobility can be obtained by the second treatment in the second atmosphere (an atmosphere containing trace amounts of oxygen and nitrogen). This is thought to be because silicon atoms are effectively terminated with nitrogen at the interface 15 between the silicon carbide member 50 and the first film 10. Meanwhile, the trace amount of oxygen repairs oxygen vacancies in the first film 10 (silicon oxide film). In this way, the second treatment improves the nitrogen termination at the interface 15 and the film quality of the first film 10. This results in a low interface state density. This results in a high carrier mobility.

[0022] In the embodiment, the temperature in the second treatment is preferably 1200° C. or higher and 1300° C. or lower. Such a temperature can suppress the interface state density and obtain high carrier mobility. According to the embodiment, a method for manufacturing a semiconductor device capable of improving characteristics can be provided.

[0023] The time during which the temperature exceeds 1200° C. in the second treatment (time tm2 shown in FIG. 3) is preferably 1 hour or more and 10 hours or less. This makes it possible to reliably suppress the interface state density. This makes it possible to more reliably obtain high carrier mobility.

[0024] In an embodiment, for example, the oxygen in the second atmosphere is O2, and the nitrogen in the second atmosphere is N2. In an embodiment, the second atmosphere preferably does not substantially contain NO. For example, the concentration of NO in the second atmosphere is preferably less than 0.3 ppm. This concentration is a volume ratio.

[0025] When the second atmosphere is substantially free of NO, for example, silicon atoms are effectively terminated with nitrogen, improving the film quality of the first film 10. That is, nitrogen in the second atmosphere acts on the interface 15, and oxygen in the second atmosphere acts on the first film 10. When the second atmosphere contains NO, nitrogen atoms and oxygen atoms are simultaneously present, making it difficult to achieve the above-mentioned effect.

[0026] The concentration of nitrogen (e.g., N2) contained in the second atmosphere is preferably 0.1% or more and less than 100%. The concentration of nitrogen (e.g., N2) contained in the second atmosphere may be 99.9% or less. This reliably suppresses the interface state density. This more reliably achieves high carrier mobility. The above concentrations are volume ratios.

[0027] An example of the temperature profile in the second treatment is shown in Figure 3. In one example, the rate of temperature increase from 700°C to 900°C is, for example, about 10°C / min. The rate of temperature increase from 900°C to 1270°C is, for example, about 5°C / min. The rate of temperature increase from 1270°C to 1300°C is, for example, about 3°C / min. The rate of temperature decrease from 1300°C to 1200°C is, for example, about 5°C / min.

[0028] In the embodiment, the first treatment is preferably carried out before the second treatment, which is a heat treatment in a first atmosphere containing hydrogen.

[0029] For example, in a sample in which a second treatment was performed in an atmosphere containing substantially no oxygen but containing nitrogen after the first treatment, the interface state density was found to be about 2.5×10 12 / cm -2 In contrast, in the sample in which the second treatment was performed in a second atmosphere containing nitrogen and a trace amount of oxygen after the first treatment, the interface state density was about 2.1 × 10 12 / cm -2 It can be the following:

[0030] For example, by heat treatment in a first atmosphere containing hydrogen, carbon atoms are removed to form a silicon-rich silicon carbide region, for example, in a region including the interface 15 between the silicon carbide member 50 and the first film 10 .

[0031] The formation of a silicon-rich silicon carbide region in the region including the interface 15 facilitates bonding of nitrogen with silicon. The subsequent second treatment more reliably terminates the silicon with nitrogen. This facilitates the formation of a connection region that satisfactorily connects the silicon carbide member 50 and the first film 10 at the interface 15 between the silicon carbide member 50 and the first film 10. In the connection region, silicon is terminated with nitrogen, and a low interface state density is stably obtained. For example, the second treatment includes bonding nitrogen to silicon present in the region between the silicon carbide member 50 and the first film 10.

[0032] For example, unnecessary oxygen in the first film 10 is removed by the first process in a first atmosphere containing hydrogen. The unnecessary oxygen may oxidize silicon carbide at high temperatures in the second process. If silicon carbide is oxidized, carbon atoms may remain in the oxide film, making it difficult to obtain high properties (e.g., high carrier mobility). Therefore, it is preferable to suppress the oxidation of silicon carbide. By removing unnecessary oxygen in the first process, undesirable oxidation of silicon carbide in the second process is suppressed.

[0033] The first treatment in the first atmosphere containing hydrogen may cause oxygen vacancies in the first film 10. The second treatment in the second atmosphere containing a trace amount of oxygen repairs the oxygen vacancies, thereby achieving high film quality.

[0034] The second treatment is performed in an atmosphere containing nitrogen and a trace amount of oxygen, thereby repairing oxygen vacancies and improving film quality. In the second treatment, the oxygen concentration is set low, thereby suppressing oxidation of silicon carbide in the second treatment.

[0035] The concentration of hydrogen in the first atmosphere is 0.01% or more and 100% or less. The first atmosphere preferably does not contain NO. The concentration of NO in the first atmosphere is, for example, 0.001 ppm or less. These concentrations are volume ratios.

[0036] If the first atmosphere in the first process contains oxygen, it becomes difficult to remove carbon from silicon carbide, making it difficult to effectively terminate with nitrogen. For example, the reduction of the interface state density is likely to be insufficient. If the first atmosphere in the first process contains oxygen, it becomes difficult to remove unnecessary oxygen contained in the first film 10. In this case, silicon carbide is likely to be oxidized in the second process. It is difficult to obtain high characteristics (for example, high carrier mobility).

[0037] If the oxygen concentration in the second atmosphere in the second treatment exceeds 1000 pm, the surface of the silicon carbide is easily oxidized, making it difficult to obtain high properties (for example, high carrier mobility).

[0038] For example, there is a reference example in which the interface states are terminated with nitrogen by oxynitridation in a nitric oxide (NO) atmosphere or a nitrous oxide (NO) atmosphere without performing the first treatment. In this reference example, an oxidation reaction occurs along with the nitrogen termination. Therefore, the characteristics deteriorate due to oxidation of silicon carbide.

[0039] In contrast, in the embodiment, the oxidation of silicon carbide can be appropriately suppressed by nitrogen and an appropriate concentration of oxygen, thereby suppressing deterioration of characteristics.

[0040] In the embodiment, in the second treatment after the first treatment in the first atmosphere containing hydrogen, the second atmosphere may contain at least one of nitric oxide and nitrous oxide. The first treatment promotes nitrogen termination and suppresses oxidation. High carrier mobility is more easily obtained compared to the above reference example in which the first treatment is not performed. When the second treatment is performed in the second atmosphere containing at least one of nitric oxide and nitrous oxide after the first treatment in the first atmosphere, the concentration of nitric oxide or nitrous oxide may be set lower than in the reference example.

[0041] 4A to 4C are schematic views illustrating the method for manufacturing a semiconductor device according to the embodiment. 4 illustrates the temperature change in the first and second processes, where the horizontal axis represents time tm and the vertical axis represents temperature Tmp.

[0042] For example, in the first treatment, heat treatment is performed in a first atmosphere containing hydrogen at a first temperature T1. The first temperature T1 is, for example, 1200° C. or higher and 1350° C. or lower. The time tm1 of the first treatment (the time during which the temperature Tmp exceeds 1200° C.) is preferably, for example, 15 minutes or higher and 10 hours or lower.

[0043] The second treatment is performed in a second atmosphere containing trace amounts of oxygen and nitrogen at a second temperature T2. The time tm2 of the second treatment is preferably 1 hour or more and 20 hours or less.

[0044] As shown in FIG. 4, between the first and second processes, the structure 10B may be heated to a temperature (third temperature T3) lower than the first temperature T1. The first and second processes may be performed continuously in the same apparatus. Alternatively, the first and second processes may be performed discontinuously in different apparatuses. In the structure 10B, a stable first film 10 is provided on the surface of the silicon carbide member 50. This reduces adverse effects even when the structure 10B is removed from the apparatus. This facilitates the process.

[0045] In the embodiment, the first process and the second process are performed after the formation of the first film 10. For example, when the first film 10 is formed after the first process, the surface of the silicon carbide member 50 is likely to be contaminated.

[0046] As shown in FIG. 2, the silicon carbide member 50 may include a first region 50r. In a first direction (Z-axis direction) from the silicon carbide member 50 to the first film 10, the first region 50r is spaced apart from the interface 15 between the silicon carbide member 50 and the first film 10. For example, the first region 50r does not contain nitrogen. Alternatively, the nitrogen concentration at the interface 15 is higher than the nitrogen concentration in the first region 50r. The nitrogen localized near the interface 15 terminates the silicon near the interface with nitrogen. The first region 50r is a bulk region spaced apart from the interface. The distance between the interface 15 and the first region 50r may be, for example, 20 nm or more.

[0047] FIG. 5 is a schematic cross-sectional view illustrating the semiconductor device according to the embodiment. As shown in FIG. 5, the semiconductor device 111 includes a first semiconductor region 51 of a first conductivity type, a second semiconductor region 52 of a second conductivity type, a third semiconductor region 53 of the first conductivity type, a fourth semiconductor region 54 of the second conductivity type, a first film 10, a first conductive film E1, a second conductive film E2, a third conductive film E3, and an insulating film I1. The semiconductor device 111 is a transistor. The semiconductor regions include, for example, silicon carbide. For example, the second semiconductor region 52 corresponds to the silicon carbide member 50. The first film 10 corresponds, for example, to a gate insulating film. The first conductive film E1 corresponds to a gate electrode. The second conductive film E2 corresponds, for example, to a source electrode. The third conductive film E3 corresponds, for example, to a drain electrode. In this example, a substrate 55 (SiC substrate) is provided.

[0048] The direction perpendicular to the Z-axis direction is the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is the Y-axis direction.

[0049] In this example, in the Z-axis direction, the first conductive film E1 is provided between the second conductive film E2 and the third conductive film E3. The substrate 55 is located between the first conductive film E1 and the third conductive film E3. A portion of the first semiconductor region 51 is located between the first conductive film E1 and the substrate 55. The first film 10 is located between the first conductive film E1 and this portion of the first semiconductor region 51. An insulating film I1 is provided between the second conductive film E2 and the first conductive film E1. The insulating film I1 insulates the second conductive film E2 from the first conductive film E1.

[0050] The second semiconductor region 52 is provided between another part of the first semiconductor region 51 and a part of the second conductive film E2. The third semiconductor region 53 and the fourth semiconductor region 54 are located between the part of the second semiconductor region 52 and the above-mentioned part of the second conductive film E2. In the X-axis direction, the third semiconductor region 53 is located between the part of the first semiconductor region 51 and the fourth semiconductor region 54. A part of the second semiconductor region 52 is located between this part of the first semiconductor region 51 and the third semiconductor region 53. The third semiconductor region 53 and the fourth semiconductor region 54 are in ohmic contact with the second conductive film E2.

[0051] In the semiconductor device 111, high mobility is obtained.

[0052] An example of an experimental result will be described below. In the experiment, a structure 10B is prepared. The structure 10B includes a silicon carbide member 50 and a first film 10. In the experiment, the first film 10 is a SiO2 film. In a first process, the structure 10B is heat-treated in a first atmosphere containing hydrogen. Thereafter, in a second process, the structure 10B is heat-treated in a second atmosphere containing nitrogen and oxygen.

[0053] In the experiments described below, the second process includes a first step process and a second step process that follows the first step process. The first step process corresponds to the process at time tx1 illustrated in FIG. 3. The second step process corresponds to the process at time tx2 illustrated in FIG. 3. The temperature of the first step process is 1300°C. The atmosphere in the first step process (second atmosphere) contains nitrogen (N2) containing oxygen (O2) at a concentration of 100 ppm. The temperature of the second step process is 1200°C. The atmosphere in the second step process contains nitrogen (N2) that does not contain oxygen.

[0054] After the second process, a first conductive film E1 is formed on the first film 10. Meanwhile, another conductive film is formed below the silicon carbide member 50. A voltage is applied between this other conductive film and the first conductive film E1. The capacitance between the other conductive film and the first conductive film E1 is measured as the applied voltage is changed. The interface state density is obtained from the measurement results.

[0055] 6(a) and 6(b) are graphs illustrating the characteristics of the semiconductor device. 6(a) and 6(b), the first atmosphere in the first process is nitrogen (N2) containing 0.3% hydrogen. In the first process, a heat treatment is performed at 1350°C for 60 minutes. Then, the second process is performed. The horizontal axis of these graphs represents the thickness t1 of the first film 10.

[0056] The vertical axis of FIG. 6(a) is the interface state density D1. The interface state density D1 corresponds to the density of the interface state at 0.2 eV. The vertical axis of FIG. 6(b) is the interface state density D2. The interface state density D2 corresponds to the density of the interface state at 0.5 eV. In FIGS. 6(a) and 6(b), the results for the first reference sample RS1, which was not subjected to the first treatment, are shown at the position where the thickness t1 is 0 nm for convenience. In the first reference sample RS1, the thickness t1 is 55 nm.

[0057] 6(a), when the thickness t1 is 25 nm to 100 nm, the interface state density D1 is lower than the interface state density D1 in the first reference sample RS1. As shown in FIG. 6(b), when the thickness t1 is 25 nm to 50 nm, the interface state density D2 is lower than the interface state density D1 in the first reference sample RS1. In this way, a low interface state density is obtained by performing the first process in the first atmosphere containing hydrogen.

[0058] 7(a) and 7(b) are graphs illustrating the characteristics of the semiconductor device. 7(a) and 7(b), the first atmosphere in the first process is nitrogen (N2) containing 1% hydrogen. In the first process, heat treatment is performed at 1350°C for 60 minutes. Thereafter, the second process is performed. The horizontal axis of these graphs is the thickness t1 of the first film 10.

[0059] The vertical axis of Fig. 7(a) represents the interface state density D1. The vertical axis of Fig. 7(b) represents the interface state density D2. In Fig. 7(a) and Fig. 7(b), the results for the first reference sample RS1, which was not subjected to the first treatment, are shown at the position where the thickness t1 is 0 nm for convenience.

[0060] 7(a), when the thickness t1 is 25 nm to 100 nm, the interface state density D1 is lower than the interface state density D1 in the first reference sample RS1. As shown in FIG. 7(b), when the thickness t1 is 25 nm to 50 nm, the interface state density D2 is lower than the interface state density D1 in the first reference sample RS1. In this way, a low interface state density is obtained by performing the first process in the first atmosphere containing hydrogen.

[0061] 8(a) and 8(b) are graphs illustrating the characteristics of the semiconductor device. 8(a) and 8(b), the first atmosphere in the first process is nitrogen (N2) containing 5% hydrogen. In the first process, a heat treatment is performed at 1350°C for 10 minutes. Then, the second process is performed. The horizontal axis of these graphs is the thickness t1 of the first film 10.

[0062] The vertical axis of Fig. 8(a) is the interface state density D1. The vertical axis of Fig. 8(b) is the interface state density D2. In Fig. 8(a) and Fig. 8(b), the results for the first reference sample RS1, which was not subjected to the first treatment, are shown at the position where the thickness t1 is 0 nm for convenience.

[0063] 8(a), when the thickness t1 is 25 nm to 60 nm, the interface state density D1 is lower than the interface state density D1 in the first reference sample RS1. As shown in FIG. 8(b), when the thickness t1 is 25 nm to 60 nm, the interface state density D2 is lower than the interface state density D1 in the first reference sample RS1. In this way, a low interface state density is obtained by performing the first process in the first atmosphere containing hydrogen.

[0064] From the above results, the thickness t1 of the first film 10 is preferably 25 nm or more and less than 90 nm. The thickness t1 may be 25 nm or more and 80 nm or less. The thickness t1 may be 25 nm or more and 60 nm or less.

[0065] In another experiment, the temperature in the first treatment was set to 1370°C, and then the second treatment was performed. In this case, the interface state density was not sufficiently low compared to the interface state density in the first reference sample RS1, which was not subjected to the first treatment. In the embodiment, the temperature (maximum temperature) in the first treatment is preferably less than 1370°C (for example, 1350°C or less).

[0066] As described above, a low interface state density can be obtained by the first treatment in a first atmosphere containing hydrogen and the second treatment in a second atmosphere containing oxygen and nitrogen that is performed after the first treatment. It has been found that such special treatments can provide a characteristic profile in structure 10B including silicon carbide member 50 and first film 10.

[0067] 9 to 14 are graphs illustrating the characteristics of the semiconductor device. 9, 11, and 13 correspond to the first sample SP1. In the first sample SP1, the thickness t1 of the first film 10 is 50 nm. In the first sample SP1, a first process is performed at 1350°C for 60 minutes in a first atmosphere containing 1% (volume ratio) hydrogen, and then a second process is performed. In the second process, the above-described first step process and second step process are performed.

[0068] 10, 12, and 14 correspond to the second sample SP2. In the second sample SP2, the thickness t1 of the first film 10 is 50 nm. In the second sample SP2, the first process is not performed, but the second process is performed. In the second process, the above-mentioned first step process and second step process are performed. The second sample SP2 corresponds to the above-mentioned first reference sample RS1. The interface state density in the first sample SP1 is lower than the interface state density in the second sample SP2.

[0069] The horizontal axis in these figures represents the position pZ along the Z-axis direction. The vertical axis on the left side of Figures 9 and 10 represents the concentration C0 of Si-N bonds or C-N bonds. The vertical axis on the right side of Figures 9 and 10 represents the Si secondary ion intensity Int. The Si secondary ion intensity Int corresponds to the Si concentration.

[0070] The vertical axis on the left in Figures 11 and 12 is the concentration C0 of Si-N bonds or C (carbon). The vertical axis on the right in Figures 11 and 12 is the secondary ion intensity Int of O (oxygen). The secondary ion intensity Int of oxygen corresponds to the oxygen concentration. The vertical axis in Figures 13 and 14 is the concentration C0 of Si-N bonds.

[0071] 9, the profile of the concentration of Si—N bonds in the first sample SP1 has a peak. The concentration of Si—N bonds decreases sufficiently from the position of the peak to the left in the figure.

[0072] 10, the profile of the Si-N bond concentration in the second sample SP2 has a peak. To the left of the peak in the figure, the concentration of Si-N bonds is higher than that in the first sample SP1. Thus, there is a difference in the profile of the Si-N bond concentration between the first sample SP1 and the second sample SP2.

[0073] 9, the Si—N concentration of silicon and nitrogen bonds at a first position p1 in a first direction (Z-axis direction) from the silicon carbide member 50 to the first film 10 is a first peak value vp1. In the first sample SP1, the first peak value vp1 is approximately 2.0×10 21 / cm 3 At the second position p2 in the first direction, the CN concentration of the carbon-nitrogen bond is a second peak value vp2. In the first sample SP1, the second peak value vp2 is approximately 3.2×10 20 / cm 3 At the third position p3 in the first direction, the CN concentration is low and stable. In this example, at the third position p3 in the first direction, the CN concentration v_CN is approximately 1.1×10 17 / cm 3 At a third position p3 in the first direction, the CN concentration v_CN is 1 / 2800 of the second peak value vp2. The third position p3 is a position in the direction from the silicon carbide member 50 to the first film 10 where the CN concentration v_CN is 1 / 2800 of the second peak value vp2.

[0074] In this example, in the first sample SP1, the Si—N concentration v_Si—N at the third position p3 is 1 / 24 of the first peak value vp1. In an embodiment, the Si—N concentration (v_Si—N) at the third position p3 is, for example, less than 1 / 20 of the first peak value vp1.

[0075] 10, the Si—N concentration of the bond between silicon and nitrogen at the first position p1 is a first peak value vp1. In the second sample SP2, the first peak value vp1 is approximately 2.2×10 21 / cm 3 At the second position p2 in the first direction, the CN concentration of the carbon-nitrogen bond is a second peak value vp2. In the second sample SP2, the second peak value vp2 is about 3.5×10 20 / cm 3 At the third position p3 in the first direction, the CN concentration v_CN is approximately 1.3 × 10 17 / cm 3 Thus, in the second sample SP2, at the third position p3 in the first direction, the CN concentration v_CN is 1 / 2800 of the second peak value vp2.

[0076] In the second sample SP2, the Si-N concentration (v_Si-N) at the third position p3 was 1.4 × 10 20 / cm 3 Thus, in the second sample SP2, the Si—N concentration (v_Si—N) at the third position p3 is 1 / 16 of the first peak value vp1. In the second sample SP2, the Si—N concentration (v_Si—N) at the third position p3 is 1 / 20 or more of the first peak value vp1. In the second sample SP2, the Si—N concentration is not sufficiently low.

[0077] In the embodiment, it is believed that a low interface state density can be obtained by the Si—N concentration (v_Si—N) at the third position p3 being sufficiently low.

[0078] For example, in the embodiment, the first peak value vp1 is 1.7×10 21 / cm 3 At the second position p2 in the first direction, the CN concentration of carbon-nitrogen bonds is the second peak value vp2. At the third position p3 in the first direction, the CN concentration (v_CN) is 1 / 2800 of the second peak value vp2. The Si-N concentration (v_Si-N) at such a third position p3 is 1.0×10 20 / cm 3 In the embodiment, it is considered that a low interface state density can be obtained because the Si—N concentration (v_Si—N) at the third position p3 is sufficiently low. The first peak value vp1 is 1.9×10 21 / cm 3 The Si-N concentration (v_Si-N) at the third position p3 is 0.9×10 20 / cm 3 The following is also fine.

[0079] 9 and 10 , the first position p1 substantially coincides with the position of the interface 15 between the silicon carbide member 50 and the first film 10. At the interface 15, the Si—N concentration of silicon and nitrogen bonds reaches a first peak value vp1. Information regarding the position of the interface 15 may be obtained, for example, by observing the structure 10B using an electron microscope. The second position p2 may substantially coincide with the first position p1.

[0080] As shown in FIGS. 9 and 10, the Si concentration becomes minimal in the first film 10. The position where this minimum occurs is, for example, a fourth position p4. There is a difference in the Si-N concentration (v_Si-N) at the fourth position p4 between the first sample SP1 and the second sample SP2. In the TOF-SIMS profile, there is a surface effect in the surface region of the sample (in the example of FIGS. 9 and 10, the region on the left side of the figure where pZ is 5 nm or less). For this reason, the surface region of the sample is ignored in determining the position of the minimal Si concentration.

[0081] 9, at a first position p1 in a first direction (Z-axis direction) from the silicon carbide member 50 to the first film 10, the Si—N concentration of bonds between silicon and nitrogen is a first peak value vp1. At a fourth position p4 in the first direction, the silicon concentration is a minimum value in the first film 10. In the example of FIG. 9, the Si—N concentration (v_Si—N) at the fourth position p4 is 1 / 24 of the first peak value vp1. Thus, in the embodiment, the Si—N concentration (v_Si—N) at the fourth position p4 is less than 1 / 20 of the first peak value vp1.

[0082] In the second sample SP2 shown in FIG. 10, the Si—N concentration (v_Si—N) at the fourth position p4 is 1 / 16 of the first peak value vp1.

[0083] As shown in FIG. 9, in the embodiment, the first peak value vp1 is 1.7×10 21 / cm 3 In this example, the first peak value vp1 is 2.0×10 21 / cm 3 At the fourth position p4 in the first direction, the silicon concentration is the minimum value in the first film 10. The Si—N concentration (v_Si—N) at such a fourth position p4 is 1.0×10 20 / cm 3 In the example shown in FIG. 9, the Si—N concentration (v_Si—N) at the fourth position p4 is 0.8×10 20 / cm 3 is.

[0084] In the second sample SP2 shown in FIG. 10, the first peak value vp1 was 2.2×10 21 / cm 3 The Si-N concentration (v_Si-N) at the fourth position p4 is 1.4 × 10 20 / cm 3 is.

[0085] 11 and 12, the oxygen concentration becomes minimum in the first film 10. The position where this minimum occurs is, for example, a fifth position p5. There is a difference in the Si—N concentration at the fifth position p5 between the first sample SP1 and the second sample SP2. In the TOF-SIMS profile, the surface region of the sample is ignored in determining the position of the minimum oxygen concentration.

[0086] 11, at the first position p1, the Si—N concentration of silicon and nitrogen bonds is a first peak value vp1. At a fifth position p5 in the first direction, the oxygen concentration is a minimum value in the first film 10. In the example of FIG. 9, the Si—N concentration (v_Si—N) at the fifth position p5 is 1 / 24 of the first peak value vp1. In an embodiment, for example, the Si—N concentration (v_Si—N) at the fifth position p5 is less than 1 / 20 of the first peak value vp1.

[0087] In the second sample SP2 shown in FIG. 12, the Si—N concentration (v_Si—N) at the fifth position p5 is 1 / 16 of the first peak value vp1.

[0088] As shown in FIG. 11, in the embodiment, the first peak value vp1 is 1.7×10 21 / cm 3 In this example, the first peak value vp1 is 2.0×10 21 / cm 3 At a fifth position p5 in the first direction, the silicon concentration is a minimum value in the first film 10. The Si—N concentration (v_Si—N) at such a fifth position p5 is 1.0×10 20 / cm 3 In the example shown in FIG. 11, the Si—N concentration (v_Si—N) at the fifth position p5 is 0.8×10 20 / cm 3 is.

[0089] In the second sample SP2 shown in FIG. 12, the first peak value vp1 was 2.2×10 21 / cm 3The Si-N concentration (v_Si-N) at the fifth position p5 is 1.4 × 10 20 / cm 3 is.

[0090] 13 and 14, there is a position (sixth position p6) that is 10 nm from the first position p1 (e.g., interface 15) in the direction from the silicon carbide member 50 toward the first film 10. There is a difference in the Si—N concentration (v_Si—N) at the sixth position p6 between the first sample SP1 and the second sample SP2.

[0091] For example, as shown in FIG. 13, the Si—N concentration of silicon and nitrogen bonds at a first position p1 in the first direction is a first peak value vp1. In the embodiment, the Si—N concentration v_Si—N) at a sixth position p6 in the first direction is less than 1 / 20 of the first peak value. In the example of FIG. 9, the Si—N concentration v_Si—N) at the sixth position p6 is 1 / 24 of the first peak value. The sixth position p6 is located in the first film 10. The distance dZ in the first direction between the first position p1 and the sixth position p6 is 10 nm. A low Si—N concentration (v_Si—N) at the sixth position p6 results in a low interface state density.

[0092] In the second sample SP2 shown in FIG. 14, the Si—N concentration (v_Si—N) at the sixth position p6 is 1 / 16 of the first peak value vp1.

[0093] 13, at a first position p1 in the first direction, the Si—N concentration of bonds between silicon and nitrogen has a first peak value vp1. In the embodiment, the first peak value is 1.7×10 21 / cm 3 In the embodiment, the Si—N concentration (v_Si—N) at the sixth position p6 in the first direction is 1.0×10 20 / cm 3 The sixth position p6 is located in the first film 10. The distance dZ in the first direction between the first position p1 and the sixth position p6 is 10 nm.

[0094] The low Si—N concentration (v_Si—N) at at least one of the third position p3, the fourth position p4, the fifth position p5, and the sixth position p6 as described above results in a low interface state density, and for example, a high carrier mobility.

[0095] In the embodiment, the Si-N concentration (v_Si-N) becomes low at at least one of the third position p3, the fourth position p4, the fifth position p5, and the sixth position p6, which is thought to be due to, for example, the densification of the first film 10 by the first process.

[0096] In the example according to the embodiment, a special structure may be obtained in which the concentration of Si is at a minimum at a fourth position p4, and in the example according to the embodiment, a special structure may be obtained in which the concentration of oxygen is at a minimum at a fifth position p5.

[0097] FIG. 15 is a schematic cross-sectional view illustrating the semiconductor device according to the embodiment. 15, in a semiconductor device 111 according to the embodiment, the silicon carbide member 50 may be a first semiconductor region 51 of a first conductivity type. The silicon carbide member 50 may be, for example, an n-type semiconductor region.

[0098] In the first sample SP1 and the second sample SP2, the silicon carbide member 50 is n-type. The concentration of n-type impurities (N in this example) in the silicon carbide member 50 in the first sample SP1 and the second sample SP2 is about 5×10 15 / cm 3 In the embodiment, the concentration of n-type impurities (P or N) in the silicon carbide member 50 (first semiconductor region 51) is 1×10 15 / cm 3 5x10 or more 20 / cm 3 The concentration of n-type impurities (P or N) in the first semiconductor region 51 may be 1×10 16 / cm 3 5x10 or more 18 / cm 3As already explained, in the embodiment, the silicon carbide member 50 may correspond to the second semiconductor region 52 of the second conductivity type.

[0099] When the silicon carbide member 50 according to the embodiment is provided in the semiconductor device 111, the silicon carbide member 50 may be applied to a region to which an electric field is applied during operation of the semiconductor device 111. The silicon carbide member 50 may be applied to a region that forms at least a part of a current path during operation of the semiconductor device 111. A low interface state density can provide stable operation.

[0100] The embodiment may include the following configurations (e.g., technical solutions). (Configuration 1) a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; At a second position in the first direction, the C-N concentration of carbon-nitrogen bonds is a second peak value; At a third position in the first direction, the CN concentration is 1 / 2800 of the second peak value; the Si—N concentration at the third position is less than 1 / 20 of the first peak value.

[0101] (Configuration 2) a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; The first peak value is 1.7×10 21 / cm 3 That's all, At a second position in the first direction, the C-N concentration of carbon-nitrogen bonds is a second peak value; the CN concentration at a third position in the first direction is 1 / 2800 of the second peak value; The Si—N concentration at the third position is 1.0×10 20 / cm 3 The semiconductor device is as follows:

[0102] (Configuration 3) a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; At a fourth position in the first direction, the concentration of silicon is at a minimum in the first film; the Si—N concentration at the fourth position is less than 1 / 20 of the first peak value.

[0103] (Configuration 4) a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; The first peak value is 1.7×10 21 / cm 3 That's all, At a fourth position in the first direction, the concentration of silicon is at a minimum in the first film; The Si—N concentration at the fourth position is 1.0×10 20 / cm 3 The semiconductor device is as follows:

[0104] (Configuration 5) a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; At a fifth position in the first direction, the concentration of oxygen is a minimum value in the first film; the Si—N concentration at the fifth position is less than 1 / 20 of the first peak value.

[0105] (Configuration 6) a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; The first peak value is 1.7×10 21 / cm 3 That's all, At a fifth position in the first direction, the concentration of oxygen is a minimum value in the first film; The Si—N concentration at the fifth position is 1.0×10 20 / cm 3 The semiconductor device is as follows:

[0106] (Configuration 7) a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; the Si—N concentration at a sixth position in the first direction is less than 1 / 20 of the first peak value; the sixth location is in the first membrane; The semiconductor device, wherein the distance in the first direction between the first position and the sixth position is 10 nm.

[0107] (Configuration 8) a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; The first peak value is 1.7×10 21 / cm 3 That's all, The Si—N concentration at the sixth position in the first direction is 1.0×10 20 / cm 3 is as follows: the sixth location is in the first membrane; The semiconductor device, wherein the distance in the first direction between the first position and the sixth position is 10 nm.

[0108] (Configuration 9) Further comprising a first conductive film; 9. The semiconductor device according to any one of configurations 1 to 8, wherein the first film is provided between the silicon carbide member and the first conductive film.

[0109] (Configuration 10) preparing a structure including a silicon carbide member and a first film containing silicon and oxygen and laminated on the silicon carbide member; performing a first process of heat treating the structure in a first atmosphere containing hydrogen; After the first treatment, a second treatment is performed in which the structure is heat-treated in a second atmosphere containing nitrogen and oxygen; The method for manufacturing a semiconductor device, wherein the concentration of the oxygen in the second atmosphere is 5 ppm or more and 1000 ppm or less.

[0110] (Configuration 11) 11. The method of manufacturing a semiconductor device according to claim 10, wherein the temperature in the second treatment is 1200° C. or higher and 1300° C. or lower.

[0111] (Configuration 12) 12. The method of manufacturing a semiconductor device according to claim 11, wherein the time during which the temperature exceeds 1200° C. in the second treatment is from 1 hour to 20 hours.

[0112] (Configuration 13) the oxygen in the second atmosphere is O2; 13. The method for manufacturing a semiconductor device according to any one of configurations 10 to 12, wherein the nitrogen in the second atmosphere is N2.

[0113] (Configuration 14) 14. The method for manufacturing a semiconductor device according to any one of configurations 10 to 13, wherein the concentration of the nitrogen contained in the second atmosphere is 0.1% or more and less than 100%.

[0114] (Configuration 15) 15. The method for manufacturing a semiconductor device according to any one of configurations 10 to 14, wherein the first film has a thickness of 25 nm or more and 60 nm or less.

[0115] (Configuration 16) 16. The method for manufacturing a semiconductor device according to any one of configurations 10 to 15, wherein the first film is in contact with the silicon carbide member.

[0116] (Configuration 17) 17. The method for manufacturing a semiconductor device according to any one of configurations 10 to 16, wherein the concentration of hydrogen in the first atmosphere is 0.01% or more and 100% or less.

[0117] (Configuration 18) 18. The method for manufacturing a semiconductor device according to any one of configurations 10 to 17, wherein the temperature in the first treatment is 1200° C. or higher and 1350° C. or lower.

[0118] (Configuration 19) 19. The method of manufacturing a semiconductor device according to configuration 18, wherein the first treatment is performed for a period of 15 minutes to 10 hours.

[0119] (Configuration 20) 20. The method for manufacturing a semiconductor device according to any one of configurations 10 to 19, wherein the second treatment includes bonding nitrogen to silicon present in a region between the silicon carbide member and the first film.

[0120] (Configuration 21) the silicon carbide member includes a first region, and in a first direction from the silicon carbide member to the first film, the first region is spaced apart from an interface between the silicon carbide member and the first film; 21. The method for manufacturing a semiconductor device according to any one of configurations 10 to 20, wherein the first region does not contain nitrogen, or the concentration of nitrogen at the interface is higher than the concentration of nitrogen in the first region.

[0121] (Configuration 22) 22. The method for manufacturing a semiconductor device according to any one of configurations 10 to 21, further comprising: between the first treatment and the second treatment, setting the structure at a temperature lower than the first temperature.

[0122] (Configuration 23) 23. The method for manufacturing a semiconductor device according to any one of configurations 10 to 22, further comprising forming a conductive film on the first film after the second treatment.

[0123] According to the embodiment, a method for manufacturing a semiconductor device capable of improving characteristics can be provided.

[0124] In this specification, "vertical" and "parallel" do not only mean strictly vertical and strictly parallel, but also include variations in the manufacturing process, and may mean substantially vertical and substantially parallel.

[0125] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configurations of the elements included in the semiconductor device, such as the silicon carbide member, semiconductor region, first film, and conductive film, are within the scope of the present invention as long as a person skilled in the art can implement the present invention in a similar manner and obtain similar effects by appropriately selecting them from known ranges.

[0126] Furthermore, any combination of two or more elements of each specific example within the scope of technical feasibility is also included within the scope of the present invention as long as it includes the gist of the present invention.

[0127] In addition, all semiconductor devices and semiconductor device manufacturing methods that can be implemented by a person skilled in the art by making appropriate design modifications based on the semiconductor device and semiconductor device manufacturing method described above as embodiments of the present invention also fall within the scope of the present invention, as long as they include the gist of the present invention.

[0128] In addition, within the scope of the concept of the present invention, a person skilled in the art may come up with various modifications and alterations, and it will be understood that these modifications and alterations also fall within the scope of the present invention.

[0129] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0130] 10...first film, 10B...structure, 15...interface, 50...silicon carbide member, 50r...first region, 51-54...first to fourth semiconductor regions, 55...substrate, 110, 111...semiconductor device, C0...concentration, D1, D2...interface state density, E1~E3...first~third conductive film, I1...insulating film, Int...secondary ion intensity, RS1: First reference sample SP1, SP2...first and second samples, T1~T3...1st~3rd temperature, Tmp...temperature, dZ...distance, p1~p6...1st~6th position, t1...thickness, tm, tm1, tm2, tx1, tx2...time, v_C-N…CN concentration, v_Si-N...Si-N concentration, vp1, vp2: first and second peak values,

Claims

1. a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; At a second position in the first direction, the C—N concentration of carbon and nitrogen bonds is a second peak value; At a third position in the first direction, the C—N concentration is 1 / 2800 of the second peak value; The Si—N concentration at the third position is less than 1 / 20 of the first peak value.

2. a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; The first peak value is 1.7×10 ２１ / cm ３ That's all, At a second position in the first direction, the C—N concentration of carbon and nitrogen bonds is a second peak value; the C—N concentration at a third position in the first direction is 1 / 2800 of the second peak value, The Si—N concentration at the third position is 1.0×10 ２０ / cm ３ The semiconductor device is as follows:

3. a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; At a fourth position in the first direction, the concentration of silicon is at a minimum in the first film; the Si—N concentration at the fourth position is less than 1 / 20 of the first peak value.

4. a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; The first peak value is 1.7×10 ２１ / cm ３ That's all, At a fourth position in the first direction, the concentration of silicon is at a minimum in the first film; The Si—N concentration at the fourth position is 1.0×10 ２０ / cm ３ The semiconductor device is as follows:

5. a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; At a fifth position in the first direction, the concentration of oxygen is a minimum value in the first film; the Si—N concentration at the fifth position is less than 1 / 20 of the first peak value.

6. a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; The first peak value is 1.7×10 ２１ / cm ３ That's all, At a fifth position in the first direction, the concentration of oxygen is a minimum value in the first film; The Si—N concentration at the fifth position is 1.0×10 ２０ / cm ３ The semiconductor device is as follows:

7. a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; the Si—N concentration at a sixth position in the first direction is less than 1 / 20 of the first peak value; the sixth location is in the first membrane; The semiconductor device, wherein the distance in the first direction between the first position and the sixth position is 10 nm.

8. a silicon carbide member; a first film laminated with the silicon carbide member and containing silicon and oxygen; Equipped with a Si—N concentration of silicon and nitrogen bonds at a first position in a first direction from the silicon carbide member to the first film is a first peak value; The first peak value is 1.7×10 ２１ / cm ３ That's all, The Si—N concentration at the sixth position in the first direction is 1.0×10 ２０ / cm ３ is as follows: the sixth location is in the first membrane; The semiconductor device, wherein the distance in the first direction between the first position and the sixth position is 10 nm.

9. Further comprising a first conductive film; 9. The semiconductor device according to claim 1, wherein said first film is provided between said silicon carbide member and said first conductive film.

10. preparing a structure including a silicon carbide member and a first film containing silicon and oxygen and laminated on the silicon carbide member; performing a first process of heat treating the structure in a first atmosphere containing hydrogen; After the first treatment, a second treatment is performed in which the structure is heat-treated in a second atmosphere containing nitrogen and oxygen; the concentration of oxygen in the second atmosphere is 5 ppm or more and 1000 ppm or less, the temperature in the first treatment is 1200°C or higher and 1350°C or lower, The method for manufacturing a semiconductor device, wherein the temperature in the second treatment is 1200° C. or higher and 1300° C. or lower.

11. The method for manufacturing a semiconductor device according to claim 10 , wherein the time during which the temperature exceeds 1200° C. in the second treatment is from 1 hour to 20 hours.

12. The oxygen in the second atmosphere is O ２ and The nitrogen in the second atmosphere is N ２ The method for manufacturing a semiconductor device according to claim 10,

13. The method for manufacturing a semiconductor device according to claim 10 , wherein the concentration of the nitrogen contained in the second atmosphere is equal to or greater than 0.1% and less than 100%.

14. The method for manufacturing a semiconductor device according to claim 10 , wherein the first film has a thickness of 25 nm or more and 60 nm or less.

15. The method for manufacturing a semiconductor device according to claim 10 , wherein the first film is in contact with the silicon carbide member.

16. 11. The method for manufacturing a semiconductor device according to claim 10, wherein a concentration of hydrogen in the first atmosphere is not less than 0.01% and not more than 100%.

17. The method for manufacturing a semiconductor device according to claim 10 , wherein the first treatment is performed for a period of 15 minutes to 10 hours.

18. The method for manufacturing a semiconductor device according to claim 10 , wherein the second treatment includes bonding nitrogen to silicon present in a region between the silicon carbide member and the first film.

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