semiconductor devices

Abstract

An embodiment provides a highly reliable semiconductor device. The semiconductor device of the embodiment includes a semiconductor portion, a terminal insulating film, a first protective film, a second electrode, a terminal electrode, a first insulating film, and a second protective film. The semiconductor portion is provided on the first electrode. The terminal insulating film is provided on the semiconductor portion. The first protective film is provided on the terminal insulating film and contains silicon and nitrogen. The second electrode is provided on the semiconductor portion of the cell region. The terminal electrode is provided on the first protective film and connected to the semiconductor portion. The first insulating film is provided on the first protective film and disposed between the second electrode and the terminal electrode. The upper portion of the first insulating film is disposed above the second electrode and the terminal electrode. The second protective film covers the first insulating film and contains silicon and nitrogen.

Description

[0001] Related applications

[0002] This application claims the benefit of priority based on Japanese Patent Application No. 2020-153313 (filing date: September 11, 2020), the entire contents of which are incorporated herein by reference. Technical Field

[0003] Embodiments of the present invention relate to a semiconductor device. Background Art

[0004] Power devices that control the amount of current supplied to electric trains and other equipment use high-voltage semiconductor devices such as IGBTs (Insulated Gate Bipolar Transistors), MOSFETs (Metal-Oxide-Semiconductor-Field-Effect-Transistors), and FRDs (Fast Recovery Diodes). These semiconductor devices are required to have high reliability. Summary of the Invention

[0005] Embodiments of the present invention provide a highly reliable semiconductor device.

[0006] In a semiconductor device according to an embodiment, a cell region and a terminal region surrounding the cell region are defined. The semiconductor device includes a first electrode, a semiconductor portion, a terminal insulating film, a first protective film, a second electrode, a terminal electrode, a first insulating film, and a second protective film. The semiconductor portion is provided on the first electrode. The first protective film is provided on the semiconductor portion in the terminal region. The first protective film is provided on the terminal insulating film and contains silicon and nitrogen. The second electrode is provided on the semiconductor portion in the cell region. An end portion of the second electrode is provided on the first protective film. The terminal electrode is provided on the first protective film in the terminal region and is connected to the semiconductor portion. The first insulating film is provided on the first protective film and is in contact with an end portion of the second electrode and the terminal electrode. The lower portion of the first insulating film is provided between the second electrode and the terminal electrode. The upper portion of the first insulating film is provided above the second electrode and the terminal electrode. The internal stress of the first insulating film is lower than the internal stress of the terminal insulating film. The second protective film covers the upper portion of the first insulating film and contains silicon and nitrogen.

[0007] In a semiconductor device according to an embodiment, a cell region and a terminal region surrounding the cell region are provided. The semiconductor device includes a first electrode, a semiconductor portion, a terminal insulating film, a first protective film, a second electrode, a terminal electrode, a first insulating film, a second protective film, and a metal film. The semiconductor portion is provided on the first electrode. The terminal insulating film is provided on the semiconductor portion in the terminal region. The first protective film is provided on the terminal insulating film and contains silicon and nitrogen. The second electrode is provided on the semiconductor portion in the cell region. An end portion of the second electrode is provided on the first protective film. The terminal electrode is provided on the first protective film in the terminal region and is connected to the semiconductor portion. The first insulating film is provided on the first protective film and is in contact with an end portion of the second electrode and the terminal electrode. The lower portion of the first insulating film is provided between the second electrode and the terminal electrode. The upper portion of the first insulating film is provided above the second electrode and the terminal electrode. The second protective film covers the upper portion of the first insulating film and contains silicon and nitrogen. The metal film is provided on the first insulating film and is connected to the second electrode. A portion of the metal film overlaps the terminal electrode and is isolated from the terminal electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a plan view showing the semiconductor device according to the first embodiment.

[0009] Figure 2 Yes Figure 1 Magnified view of area A.

[0010] Figure 3 is based on Figure 2 The cross-sectional view along the BB' line is shown.

[0011] Figure 4 It is an enlarged plan view showing a semiconductor device according to a second embodiment.

[0012] Figure 5 is based on Figure 4 The cross-sectional view along the CC' line is shown.

[0013] Figure 6 This is an enlarged cross-sectional view showing a semiconductor device according to a third embodiment. DETAILED DESCRIPTION

[0014] Hereinafter, each embodiment will be described with reference to the drawings.

[0015] The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratios between parts, etc., are not necessarily the same as in reality. Furthermore, even when depicting the same parts, the dimensions and ratios may differ depending on the drawing. Furthermore, in this specification and the drawings, elements identical to those described in the preceding drawings are denoted by the same reference numerals, and detailed descriptions are omitted as appropriate.

[0016] (First embodiment)

[0017] Figure 1 1 is a plan view showing the semiconductor device according to this embodiment. Figure 2 Yes Figure 1 Magnified view of area A. Figure 3 is based on Figure 2 The cross-sectional view along the BB' line is shown. Figures 1 to 3 The wiring layer is omitted. Figure 1 、 Figure 2 In FIG, a first low stress insulating film 51 described later is indicated by a single dot chain line. Figure 2 In FIG. 1 , ridge lines of a second protective film 42 described later are indicated by thin lines.

[0018] The semiconductor device 101 of this embodiment is used, for example, to control the current supplied to a vehicle such as a railway vehicle, and applies a voltage of several thousand V. The semiconductor device 101 of this embodiment is capable of flowing high current and is a power semiconductor device with high voltage resistance even at high voltage and high temperature, such as a diode.

[0019] like Figures 1 to 3 As shown in FIG. 1 , the semiconductor device 101 includes a cell region CE for controlling current and a terminal region EN1 provided around the cell region CE. Figure 1 、 Figure 2 As shown, the cell region CE is the region inside the two-dot chain line, and the termination region EN1 is the region outside the two-dot chain line. In the termination region EN1, the cell region CE side is referred to as the cell side CS, and the outside of the cut line is referred to as the termination side TS.

[0020] The semiconductor device 101 has a stacked structure and is in the shape of a substantially rectangular parallelepiped. Figure 2 as well as Figure 3 As shown, the semiconductor device 101 generally includes a semiconductor portion 10 , a first electrode 21 , a second electrode 22 , a third electrode 23 , a terminal electrode 28 , a terminal insulating film 31 , a first protective film 41 , a second protective film 42 , and a first low-stress insulating film 51 .

[0021] The first electrode 21 is provided on the entire bottom surface of the semiconductor device 101 and has a substantially flat plate shape. The first electrode 21 is, for example, a cathode electrode.

[0022] The semiconductor portion 10 is provided on the first electrode 21 and is substantially in the shape of a rectangular parallelepiped. Figure 3 As shown, the semiconductor portion 10 includes a first semiconductor layer 11, a second semiconductor layer 12, and a third semiconductor layer 13. The semiconductor portion 10 includes, for example, silicon (Si) or silicon carbide (SiC).

[0023] The first semiconductor layer 11 is of the first conductivity type, for example, n-type. The first semiconductor layer 11 includes a lower semiconductor layer 11a, an upper semiconductor layer 11b, and a terminal semiconductor layer 11c. The lower semiconductor layer 11a is provided on the first electrode 21 in the cell region CE and the terminal region EN1 and is in contact with the first electrode 21. The lower semiconductor layer 11a is composed of, for example, n-type. + The upper semiconductor layer 11b is provided on the lower semiconductor layer 11a in the cell region CE and the terminal region EN1. The upper semiconductor layer 11b is composed of, for example, n － The terminal semiconductor layer 11c is provided on the upper semiconductor layer 11b in the terminal region EN1 and is composed of, for example, n + type of semiconductor. In addition, “n － Type" means the same as "n + The carrier concentration is lower than that of the "type". The terminal semiconductor layer 11c is formed into a frame shape surrounding the cell area CE in a plan view. The terminal semiconductor layer 11c is provided on the terminal side TS of the semiconductor device 101, for example, arranged along the terminal side TS.

[0024] like Figure 3 As shown, the second semiconductor layer 12 is provided on the upper semiconductor layer 11b in the cell region CE, and a portion of the terminal side TS is disposed in the terminal region EN1. The second semiconductor layer 12 is of the second conductivity type, for example, p + The second semiconductor layer 12 is, for example, an anode-side semiconductor layer, and is connected to a second electrode 22 provided thereon.

[0025] The third semiconductor layer 13 is, for example, a guard ring. In the terminal region EN1, a plurality of third semiconductor layers 13 are provided on the upper semiconductor layer 11b, for example, three third semiconductor layers 13 are provided. The third semiconductor layer 13 is of the second conductivity type, for example, p + The third semiconductor layer 13 is connected to the third electrode 23 provided thereon. The plurality of third semiconductor layers 13 are substantially similar frame-shaped layers of different sizes in a plan view and are concentrically arranged to surround the cell area CE.

[0026] Termination insulating film 31 is provided on semiconductor portion 10 in termination region EN1 and is in contact with the upper surface of semiconductor portion 10. Specifically, termination insulating film 31 covers the upper surface of semiconductor portion 10 except for the areas in contact with second electrode 22, third electrode 23, and termination electrode 28. As a result, termination insulating film 31 has a substantially flat shape with few steps or bends. Termination insulating film 31 contains silicon and oxygen (O), for example, silicon oxide (SiO).

[0027] The first protective film 41 is provided on the termination insulating film 31 and covers the upper surface of the termination insulating film 31. As a result, the first protective film 41 has a substantially flat shape with almost no steps and a curved portion. The first protective film 41 contains silicon and nitrogen (N), for example, silicon nitride (SiN).

[0028] like Figures 1 to 3 As shown, the second electrode 22 is provided on the semiconductor portion 10 at the cell side CS between the cell region CE and the terminal region EN1. The second electrode 22 is, for example, an anode electrode. The second electrode 22 includes, for example, aluminum (Al). Figure 3 As shown, the second electrode 22 has a main portion 22a and an end portion 22b. The main portion 22a is provided on the second semiconductor layer 12 in the cell region CE, and its lower surface is connected to the second semiconductor layer 12. The main portion 22a is in contact with the termination insulating film 31 and the first protective film 41 on the termination side TS.

[0029] The end portion 22b protrudes from the upper portion of the main body portion 22a toward the termination side TS. The end portion 22b is disposed on the first protection film 41 on the cell side CS of the termination region EN1, and the lower surface thereof is in contact with the first protection film 41.

[0030] like Figure 1 、 Figure 2 As shown, the third electrodes 23 are substantially frame-shaped and concentrically arranged in the terminal region EN1 so as to surround the cell region CE. Figure 3 As shown, the third electrode 23 includes a main portion 23a and a contact portion 23b. The main portion 23a is disposed on the first protective film 41. The lower surface of the main portion 23a is in contact with the first protective film 41. The contact portion 23b extends downward from the main portion 23a, is disposed on the third semiconductor layer 13, and is connected to the third semiconductor layer 13. The contact portion 23b penetrates the terminal insulating film 31 and the first protective film 41. The third electrode 23 comprises, for example, aluminum.

[0031] like Figure 1 、 Figure 2 As shown in FIG. 1 , the terminal electrode 28 is in a substantially frame shape surrounding the cell region CE in the terminal region EN1. Figure 3 As shown, the terminal electrode 28 has a main portion 28a and a contact portion 28b.

[0032] The main body 28a is provided on the first protective film 41. The lower surface of the main body 28a is in contact with the first protective film 41. Figure 3 As shown, the angle β formed between the side surface 28D of the main body 28a facing the terminal side TS and the upper surface 28B of the terminal electrode 28 is preferably greater than 100 degrees. The contact portion 28b extends downward from the main body 28a, is provided on the terminal semiconductor layer 11c, and is connected to the terminal semiconductor layer 11c. The contact portion 28b penetrates the terminal insulating film 31 and the first protective film 41. The terminal electrode 28 is made of aluminum, for example.

[0033] like Figure 1 、 Figure 2 As shown, the first low stress insulating film 51 is provided in a substantially frame shape surrounding the cell region CE. Figure 3 As shown, the first low-stress insulating film 51 includes a lower portion 51a and an upper portion 51b. The lower portion 51a is provided on the first protective film 41 and is disposed between the second electrode 22 and the terminal electrode 28. Specifically, the lower portion 51a is provided in the gap between the second electrode 22, the plurality of third electrodes 23, and the terminal electrode 28, and is in contact with the end portion 22b of the second electrode 22, the main body portions 23a of the plurality of third electrodes 23, and the side surface of the main body portion 28a of the terminal electrode 28.

[0034] The upper portion 51b is provided above the lower portion 51a and is disposed above the second electrode 22, the third electrode 23, and the terminal electrode 28. The upper portion 51b is in contact with the upper surface of the end portion 22b of the second electrode 22, the upper surface of the main portion 23a of the third electrode 23, and the upper surface 28B of the main portion 28a of the terminal electrode 28 on the cell side CS. In other words, the first low-stress insulating film 51 covers the end portion 22b of the second electrode 22 and the end portion of the terminal electrode 28 on the cell side CS.

[0035] In addition, the first low-stress insulating film 51 only needs to be in contact with at least the side surface of the end portion 22 b of the second electrode 22 and the side surface of the terminal electrode 28 on the cell side CS.

[0036] The upper portion 51b has an upper surface 51B and side surfaces 51C and 51D that are in contact with the upper surface 51B. The upper surface 51B is, for example, flat. The side surface 51C is located on the cell side CS, and the side surface 51D is located on the terminal side TS. The angle α1 formed between the side surface 51C of the upper portion 51b and the upper surface 51B is preferably, for example, greater than 100 degrees. The angle α2 formed between the side surface 51D of the upper portion 51b and the upper surface 51B is preferably, for example, greater than 100 degrees.

[0037] The first low-stress insulating film 51 (first insulating film) contains silicon, oxygen, nitrogen, and hydrogen (H), and for example, contains silicon oxynitride (SiON) and hydrogen. Compared to the first protective film 41, which is composed of silicon nitride, the first low-stress insulating film 51 contains more hydrogen and less nitrogen. Furthermore, because the first low-stress insulating film 51 contains less silicon oxide and hydrogen bonding (SiO-H), it has higher voltage resistance. Furthermore, the first low-stress insulating film 51 has a longer lifespan under high electric fields than the first protective film 41 and the second protective film 42. Furthermore, because the first low-stress insulating film 51 has a higher breakdown electric field than the first protective film 41 and the second protective film 42, it can maintain its insulating properties even under high electric fields. Furthermore, the first low-stress insulating film 51 has an internal stress of, for example, less than 10 MPa. The internal stress of the first low-stress insulating film 51 is lower than that of the first protective film 41 and the termination insulating film 31. For example, the internal stress of the first low-stress insulating film 51 is less than one-fortieth of the internal stress of the first protective film 41. As described above, the thick first low stress insulating film 51 has high withstand voltage and high insulation properties even under high electric fields. Ions easily penetrate the first low stress insulating film 51 compared to the first and second protective films 41 and 42 made of silicon nitride.

[0038] like Figure 1 、 Figure 2 As shown, the second protection film 42 surrounds the cell region CE in the terminal region EN1 in a frame shape, and a portion of the cell side CS is provided in the cell region CE. Figure 3 As shown, the second protective film 42 is provided on the first low-stress insulating film 51. The second protective film 42 covers the side surfaces 51C and 51D and the upper surface 51B of the upper portion 51b of the first low-stress insulating film 51. The second protective film 42 includes an upper portion 42b, side portions 42c and 42d, and electrode contact portions 42e and 42f. The upper portion 42b is in contact with the upper surface of the upper portion 51b of the first low-stress insulating film 51. The side portion 42c is provided on the cell side CS of the upper portion 42b and is in contact with the side surface 51C of the first low-stress insulating film 51. The side portion 42d is provided on the terminal side TS of the upper portion 42b and is in contact with the side surface 51D of the first low-stress insulating film 51. The angle formed by the side portion 42c of the second protective film 42 and the inner surface of the upper portion 42b is substantially the same as angle α1, and the angle formed by the side portion 42d of the second protective film 42 and the inner surface of the upper portion 42b is substantially the same as angle α2. As described above, the angle α1 and the angle α2 are preferably equal to or greater than 100 degrees, for example.

[0039] The electrode contact portion 42e is provided on the cell side CS of the side portion 42c and on the end portion 22b of the second electrode 22. The electrode contact portion 42e is in contact with the upper surface of the end portion 22b of the second electrode 22 and is parallel to the upper surface of the end portion 22b. The angle formed by the electrode contact portion 42e and the inner surface of the side portion 42c is substantially the same as the angle α1.

[0040] The electrode contact portion 42f is provided on the terminal side TS of the side portion 42d and on the main body portion 28a of the terminal electrode 28. The electrode contact portion 42f contacts the upper surface 28B and side surface 28D of the terminal electrode 28, as well as the first protective film 41. The angle formed by the inner surface of the electrode contact portion 42f is substantially the same as the angle β, and is preferably, for example, greater than 100 degrees.

[0041] The second protective film 42 contains silicon and nitrogen. The second protective film 42 suppresses ion intrusion together with the first protective film 41. The second protective film 42 is, for example, a silicon nitride film, and preferably has the same composition as the first protective film 41.

[0042] like Figure 2 As shown, the first low-stress insulating film 51 is thicker than any of the termination insulating film 31, the first protective film 41, and the second protective film 42. The thickness of the upper portion 51b is preferably 5 μm or greater, for example. Furthermore, the thickness of the first low-stress insulating film 51 is preferably no greater than approximately 40 times the thickness of the first protective film 41.

[0043] In this embodiment, by making the angle α1 formed by the upper surface 51B and the side surface 51C of the first low-stress insulating film 51, and the angle α2 formed by the upper surface 51B and the side surface 51D greater than 100 degrees, the angle formed by the inner surface of the upper portion 42b and the side portion 42c of the second protective film 42, and the angle formed by the inner surface of the upper portion 42b and the side portion 42d are also greater than 100 degrees, but it is not limited to this and can also be greater than 90 degrees.

[0044] Similarly, the angle β formed between the side surface 28D and the upper surface 28B of the terminal electrode 28 is preferably equal to or greater than 100 degrees, but is not limited thereto and may be equal to or greater than 90 degrees.

[0045] The semiconductor device 101 of this embodiment is a diode, but may also be another high-voltage semiconductor device, such as an IGBT, MOSFET, or other high-voltage semiconductor device. In such a case, although the structure of the cell region CE of the semiconductor device 101 may vary, the structure of the terminal side TS of the second electrode 22 may be applied to the electrode on the anode side.

[0046] Next, the operation of the semiconductor device 101 according to this embodiment will be described.

[0047] The semiconductor device 101 of this embodiment is disposed in a sealing resin. The sealing resin is, for example, a thermosetting resin such as epoxy resin or a gel such as silicone resin, and contains a silica filler.

[0048] In the off state, a positive potential is applied to the first electrode 21, for example, as a cathode electrode, from a power supply. A negative potential is applied to the second electrode 22, for example, as an anode electrode, from a power supply. The terminal electrode 28 is connected to the first electrode 21 via the semiconductor portion 10 in contact with the first electrode 21, and therefore has a substantially equal positive potential to that of the first electrode 21. Consequently, the cell side CS of the semiconductor portion 10 in the terminal region EN1 has a negative potential. Furthermore, the depletion layer formed in the upper semiconductor layer 11b of the terminal region EN1 does not extend further toward the terminal side TS than the terminal semiconductor layer 11c.

[0049] On the other hand, when the sealing resin reaches a high temperature due to the inflow of a large current during conduction, the mobile ions contained within the sealing resin become more mobile. Negative mobile ions are attracted to the positively charged terminal semiconductor layer 11c side, while positive mobile ions are attracted from the terminal semiconductor layer 11c side to the negatively charged cell side CS of the semiconductor portion 10 in the terminal region EN1. Since the second protective film 42 does not allow the passage of ions, damage to the terminal region EN1 caused by the intrusion of mobile ions is suppressed. Furthermore, the second protective film 42, provided on the thick first low-stress insulating film 51, isolates the mobile ions from the semiconductor portion 10 in the terminal region EN1 at a distance, effectively suppressing the reduction in withstand voltage caused by the mobile ions.

[0050] On the other hand, the second protective film 42 has high internal stress, so cracks may form in curved portions, where stress is likely to concentrate. The second protective film 42 is configured such that the angle formed by the inner surfaces of the upper portion 42b and the side portion 42c, and the angle formed by the inner surfaces of the upper portion 42b and the side portion 42d, are, for example, 100 degrees or greater. This suppresses stress concentration at the corners C1 where the upper portion 42b joins the side portion 42c, and C2 where the upper portion 42b joins the side portion 42d, thereby inhibiting the formation of cracks.

[0051] Even if cracks develop at the corners C1 and C2, mobile ions that penetrate the first low-stress insulating film 51 through the cracks will be blocked by the first protective film 41 at the lower portion 51a of the first low-stress insulating film 51. Since the first protective film 41 is substantially flat with few steps or bends, it is less susceptible to cracking than the second protective film 42. Therefore, even if mobile ions penetrate the first low-stress insulating film 51, the first protective film 41 prevents them from penetrating the termination insulating film 31 and the semiconductor portion 10.

[0052] The second protective film 42 is in contact with the upper surface of the second electrode 22 and the upper surface 28B of the terminal electrode 28. This further suppresses the intrusion of mobile ions into the first low-stress insulating film 51. Furthermore, the second protective film 42 covers the upper surface 28B and side surface 28D of the terminal electrode 28, further suppressing the intrusion of mobile ions. Furthermore, the angle formed by the inner surface of the electrode contact portion 42f of the second protective film 42 is set to, for example, 100 degrees or greater. This suppresses the formation of cracks in the corner C3 of the electrode contact portion 42f, further suppressing the intrusion of mobile ions. Furthermore, the front end of the electrode contact portion 42f of the second protective film 42 is positioned closer to the terminal side TS than the terminal electrode 28 and in contact with the first protective film 41. This closes off any potential intrusion points for mobile ions.

[0053] Hereinafter, a method for manufacturing the semiconductor device 101 according to this embodiment will be described.

[0054] First, the semiconductor portion 10 is formed by, for example, epitaxial growth. Impurities are implanted into predetermined portions of the semiconductor portion 10 to form the first semiconductor layer 11, the second semiconductor layer 12, and the third semiconductor layer 13. A conductive first electrode 21 is formed on the semiconductor portion 10.

[0055] Next, a termination insulating film 31 such as a silicon oxide film is formed in the termination region EN1 on the semiconductor portion 10. The termination insulating film 31 is formed on the substantially flat upper surface of the semiconductor portion 10 to be a substantially flat film with almost no steps or bends.

[0056] Next, a first protective film 41 is formed on the termination insulating film 31. First protective film 41 is formed on the substantially flat termination insulating film 31, resulting in a substantially flat film. First protective film 41 is formed, for example, by chemical vapor deposition (CVD) using plasma. For example, a gas containing silicon hydroxide (SiH4, silane) and a gas containing ammonia (NH3) are used for the first protective film 41. Specifically, plasma CVD uses nitrogen as the carrier gas and silane and ammonia as the reaction gases.

[0057] Next, the second electrode 22, the third electrode 23, and the terminal electrode 28 are formed. For example, predetermined portions of the terminal insulating film 31 and the first protective film 41 are removed by etching to the upper surface of the semiconductor portion 10, thereby forming the main portion 22a of the second electrode 22, the contact portion 23b of the third electrode 23, and the contact portion 28b of the terminal electrode 28.

[0058] Next, a first low-stress insulating film 51 is formed between the second electrode 22 and the terminal electrode 28. The first low-stress insulating film 51 is formed, for example, by plasma CVD. The first low-stress insulating film 51 is formed using, for example, a gas containing silane. Specifically, plasma CVD uses, for example, nitrogen as a carrier gas and nitrous oxide (N2O) as a reaction gas.

[0059] A first low-stress insulating film 51 is formed by plasma CVD between the second electrode 22 and the terminal electrode 28. Since the first low-stress insulating film 51 is formed by CVD, it can be formed with high precision over the first protective film 41, the second electrode 22, the third electrode 23, and the terminal electrode 28, which have step differences.

[0060] Next, the first low-stress insulating film 51 is etched to form the upper surface 51B and the side surfaces 51C and 51D on the first low-stress insulating film 51 .

[0061] Next, a second protective film 42 is formed on the first low-stress insulating film 51, the second electrode 22, and the terminal electrode 28. The second protective film 42 is formed by, for example, plasma CVD using the same gas as that used for the first protective film 41.

[0062] Next, the effects of the semiconductor device 101 according to this embodiment will be described.

[0063] According to the semiconductor device 101 of this embodiment, a termination insulating film 31, such as a silicon oxide film, is formed on the substantially flat upper surface of the semiconductor portion 10, and a first protective film 41, such as silicon nitride, is formed on the termination insulating film 31. Thus, the first protective film 41 is a substantially flat film with few steps and is provided on the termination insulating film 31. As a result, the first protective film 41 can suppress the formation of cracks and can also inhibit the intrusion of ions into the semiconductor portion 10.

[0064] A first low-stress insulating film 51 is provided on the first protective film 41, between the second electrode 22 and the terminal electrode 28. The first low-stress insulating film 51 has a lower portion 51a positioned between the second electrode 22, the third electrode 23, and the terminal electrode 28, and an upper portion 51b positioned above the second electrode 22, the third electrode 23, and the terminal electrode 28. The first low-stress insulating film 51 has low internal stress. Therefore, even if the thickness of the upper portion 51b is set to, for example, 5 μm or greater and 40 times or less the thickness of the first protective film 41, wafer deformation is unlikely. Providing a thick insulating film in the terminal region EN1 improves insulation, suppresses breakdown voltage degradation caused by mobile ions, and improves the reliability of the terminal region EN1 of the semiconductor device 101.

[0065] As described above, the semiconductor device 101 of this embodiment further improves reliability by thickening the first low-stress insulating film 51. However, thickening other films is not practical. For example, when the first protective film 41 is thickened, the internal stress of the first protective film 41, which is composed of, for example, silicon nitride, is high. If it is formed thicker, it may cause deformation such as wafer warping. In addition, if the terminal insulating film 31, which has high voltage resistance, is formed thicker, since the terminal insulating film 31 is composed of, for example, a silicon oxide film, high stress is generated between the terminal insulating film 31 and the adjacent semiconductor portion 10 containing silicon. Furthermore, a thick terminal insulating film 31 makes microfabrication by etching and other methods difficult, resulting in poor processability.

[0066] Furthermore, in the semiconductor device 101 of this embodiment, the second protective film 42 covers the upper portion 51b of the first low-stress insulating film 51, thereby suppressing the intrusion of mobile ions into the first low-stress insulating film 51. Furthermore, by covering the first low-stress insulating film 51, which is in contact with the second electrode 22 on the cell side CS and with the terminal electrode 28 on the terminal side TS, with the flat first protective film 41 provided below and the second protective film 42 provided above, a thick insulating film can be provided in the terminal region EN1, thereby improving reliability.

[0067] Furthermore, by setting the angles formed between the side surface 51C and the upper surface 51B of the upper portion 51b of the first low-stress insulating film 51, and the angle formed between the side surface 51D and the upper surface 51B to 100 degrees or greater, the angles formed between the inner surfaces of the upper portion 42b and the side portion 42c, and the angles formed between the inner surfaces of the upper portion 42b and the side portion 42d of the second protective film 42 are set to 100 degrees or greater. This suppresses the formation of cracks at the corners C1 between the upper portion 42b and the side portion 42c, and the corners C2 between the upper portion 42b and the side portion 42d, where internal stress is likely to concentrate, and thus suppresses the intrusion of mobile ions through the cracks.

[0068] Furthermore, by setting the angle β between the upper surface 28B and the side surface 28D of the terminal electrode 28 to be greater than 100 degrees, the angle formed by the inner surface of the electrode contact portion 42f of the second protective film 42 is also greater than 100 degrees. This prevents cracks from forming at the corner C3 of the electrode contact portion 42f.

[0069] Furthermore, the electrode contact portion 42f of the second protective film 42 contacts the upper surface 28B and the side surface 28D of the terminal electrode 28. Furthermore, the tip of the electrode contact portion 42f of the second protective film 42 contacts the first protective film 41 closer to the terminal side TS than the terminal electrode 28. This effectively suppresses the intrusion of attracted negative mobile ions.

[0070] (Second embodiment)

[0071] The semiconductor device 102 of this embodiment has a single fourth semiconductor layer 14 in the semiconductor portion 10 in the termination region EN2, rather than a plurality of third semiconductor layers 13. The semiconductor device 102 also includes a metal film 61, a metal member 62, and a second low-stress insulating film 52 (second insulating film). The second low-stress insulating film 52 contains silicon, oxygen, nitrogen, and hydrogen, and, for example, contains silicon oxynitride and hydrogen. Compared to the first protective film 41 or the second protective film 42, which contain silicon nitride, the second low-stress insulating film 52 contains more hydrogen and less nitrogen.

[0072] Figure 4 It is an enlarged plan view showing the semiconductor device according to this embodiment. Figure 5 yes Figure 4 The cross-sectional view of the CC' line is shown in FIG. Figure 4 In FIG, the ridge lines of the second protection film 42 are indicated by thin lines, and the first low stress insulating film 51 and the second low stress insulating film 52 described later are indicated by dashed lines. Figure 4 、 Figure 5 In the figure, the wiring layer is omitted.

[0073] like Figure 5 As shown, the semiconductor portion 10 includes a first semiconductor layer 11 , a second semiconductor layer 12 and a fourth semiconductor layer 14 .

[0074] The fourth semiconductor layer 14 is, for example, RESURF (Reduced Surface Field). The fourth semiconductor layer 14 is provided on the upper semiconductor layer 11b in the terminal region EN2 and is in contact with the terminal side TS of the second semiconductor layer 12. The fourth semiconductor layer 14 is of the second conductivity type, for example, P － The fourth semiconductor layer 14 has a potential substantially the same as that of the second semiconductor layer 12, for example, substantially 0 V. Like the second semiconductor layer 12, the fourth semiconductor layer 14 has a substantially frame shape surrounding the cell region CE.

[0075] The terminal insulating film 31 covers the semiconductor portion 10 except for the region in contact with the second electrode 22 and the terminal electrode 29. The terminal insulating film 31 is in contact with the terminal semiconductor layer 11c from the terminal electrode 29 to the terminal side TS.

[0076] The angle formed between the upper surface 29B and the side surface 29D of the main body portion 29 a of the terminal electrode 29 is approximately 90 degrees.

[0077] The lower portion 51a of the first low-stress insulating film 51 is disposed between the second electrode 22 and the terminal electrode 29. The lower surface of the lower portion 51a of the first low-stress insulating film 51 is in contact with the first protective film 41, and the side surfaces are in contact with the side surfaces of the end portion 22b of the second electrode 22 and the side surfaces of the main portion 29a of the terminal electrode 29 on the cell side CS.

[0078] The upper portion 51b of the first low-stress insulating film 51 contacts the upper surface of the end portion 22b of the second electrode 22 and the upper surface of the main portion 29a of the terminal electrode 29. The relative dielectric constant of the first low-stress insulating film 51 is 4.8.

[0079] The metal film 61 is, for example, in a roughly frame-shaped configuration that surrounds the cell region CE. The metal film 61 includes an upper portion 61b, a side portion 61c, and an electrode contact portion 61e. The upper portion 61b is in contact with the upper surface 51B of the first low-stress insulating film 51. The side portion 61c is provided on the cell side CS of the upper portion 61b and is in contact with the side surface 51C of the first low-stress insulating film 51. The electrode contact portion 61e is provided on the cell side CS of the side portion 61c and is in contact with the upper surface of the main body 22a of the second electrode 22. The angle formed by the inner surfaces of the upper portion 61b and the side portion 61c of the metal film 61 and the angle formed by the inner surfaces of the side portion 61c and the electrode contact portion 61e of the metal film 61 are substantially the same as the angle α1. The metal film 61 is, for example, made of a metal containing copper (Cu).

[0080] The tip end 61bb of the upper portion 61b overlaps with the main portion 29a of the terminal electrode 29 and is separated from the main portion 29a. The upper portion 51b of the first low-stress insulating film 51 is interposed between the tip end 61bb of the metal film 61 and the main portion 29a of the terminal electrode 29. Thus, the tip end 61bb of the metal film 61 and the main portion 29a of the terminal electrode 29 function as a capacitor C connected in parallel with the second electrode 22 and the second semiconductor layer 12. The tip end 61bb of the metal film 61 does not protrude from the upper surface 51B of the first low-stress insulating film 51 but is positioned within the plane of the upper surface 51B.

[0081] The portion of the metal film 61 that constitutes the capacitor C may be another portion instead of the front end portion 61bb. The metal film 61 may be further stretched to constitute the capacitor C at the intermediate portion.

[0082] The second low-stress insulating film 52 has, for example, a substantially frame shape surrounding the cell region CE and is provided on the terminal side TS of the first low-stress insulating film 51. The second low-stress insulating film 52 includes a lower portion 52a and an upper portion 52b. The lower portion 52a is provided on the first protective film 41, is disposed on the terminal side TS of the terminal electrode 29, and is in contact with the side surface of the main body portion 29a.

[0083] The upper portion 52b is provided on the main body 29a of the terminal electrode 29. The upper portion 52b is isolated from the upper portion 51b of the first low-stress insulating film 51 on the upper surface 29B of the terminal electrode 29. The upper portion 52b includes an upper surface 52B, a side surface 52C on the cell side CS that is in contact with the upper surface 52B, and a side surface 52D on the terminal side TS. The angle α3 formed between the side surface 52C of the upper portion 52b and the upper surface 52B is preferably, for example, greater than 100 degrees. The angle formed between the side surface 52D of the upper portion 52b and the upper surface 52B is, for example, approximately 90 degrees. The angle formed between the side surface 52C of the upper portion 52b and the upper surface 29B of the terminal electrode 29 is substantially the same as the angle α3.

[0084] like Figure 5 As shown, the second low-stress insulating film 52 is thicker than the termination insulating film 31, the first protective film 41, and the second protective film 42. The thickness of the upper portion 52b is preferably 5 μm or greater. Furthermore, the second low-stress insulating film 52 is preferably no thicker than about 40 times the thickness of the first protective film 41.

[0085] The second low-stress insulating film 52 includes substantially the same material as that of the first low-stress insulating film 51 , for example, is composed of substantially the same composition as that of the first low-stress insulating film 51 , and has the same characteristics.

[0086] The second protective film 42 is provided from the first low-stress insulating film 51 to the second low-stress insulating film 52. The second protective film 42 includes an upper portion 42b and side portions 42c and 42d provided on the first low-stress insulating film 51, an electrode contact portion 42g in contact with the terminal electrode 29, and an upper portion 42hb and side portions 42hc provided on the second low-stress insulating film 52. Near a corner C4 between the upper portion 42b and the side portion 42d, the second protective film 42 is in contact with a front end portion 61bb of the upper portion 61b of the metal film 61 and the terminal side TS of the upper surface 51B of the first low-stress insulating film 51.

[0087] The electrode contact portion 42g contacts the upper surface 29B of the terminal electrode 29. The side portion 42hc contacts the side surface 52C of the second low-stress insulating film 52. The upper portion 42hb contacts the upper surface 52B of the second low-stress insulating film 52. The angle formed by the side portion 42d and the inner surface of the electrode contact portion 42g is substantially the same as angle α2. The angle formed by the upper portion 42hb and the inner surface of the side portion 42hc is substantially the same as angle α3, preferably not less than 100 degrees. The angle formed by the side portion 42hc and the inner surface of the electrode contact portion 42g is substantially the same as angle α3.

[0088] The film thickness of the electrode contact portion 42g of the second protective film 42 is thicker than the film thickness of the other portions of the second protective film 42. The relative dielectric constant of the second protective film 42 is 7.0.

[0089] The metal member 62 is generally rectangular and made of copper. For example, the metal member 62 has a generally frame-like shape that surrounds the cell area CE. The metal member 62 is provided on the second electrode 22 and is connected to the electrode contact portion 61e of the metal film 61. Specifically, the metal member 62 is provided on the upper surface of the main body 22a of the second electrode 22, in the area where the electrode contact portion 61e of the metal film 61 is located. The upper surface of the metal member 62 is located slightly above the upper portions 42b and 42hb of the second protective film 42.

[0090] The metal member 62 can also be used in the configuration of the first embodiment. For example, the metal film 61 may not be provided on the first low-stress insulating film 51 , and the metal member 62 may not be connected to the metal film 61 .

[0091] Next, the operation of the semiconductor device 102 according to this embodiment will be described.

[0092] The semiconductor device 102 of this embodiment is disposed within a sealing resin. The lower surface of the first electrode 21 is connected to the substrate, and the upper surface of the metal member 62 is connected to the substrate. Thus, heat is dissipated from the semiconductor device 102 via the first electrode 21 and the metal member 62. Furthermore, the semiconductor device 102 receives a load from the substrate between the first electrode 21 and the metal member 62.

[0093] Furthermore, because semiconductor device 102 is a high-speed power semiconductor, its carrier storage capacity is small. Consequently, for example, when the switch is turned off, the carriers may decrease rapidly, causing electrical oscillations to occur between the anode-side second electrode 22 and the second semiconductor layer 12 during reverse recovery. In contrast, capacitor C absorbs the electrical oscillations between the second electrode 22 and the second semiconductor layer 12, reducing their impact on external conditions.

[0094] Furthermore, the side portion 42d, the electrode contact portion 42g, the side portion 42hc, the first low-stress insulating film 51, and the second low-stress insulating film 52 of the second protective film 42 suppress discharge from the front end portion 61bb of the metal film 61. Furthermore, the thick electrode contact portion 42g, which is in contact with the terminal electrode 29, effectively suppresses discharge.

[0095] Furthermore, for example, the fourth semiconductor layer 14 serving as RESURF has substantially the same potential as the second semiconductor layer 12 , thereby suppressing the concentration of the electric field in the termination region EN2 during the turn-off period.

[0096] Furthermore, the semiconductor device 102 is disposed within the sealing resin, similar to the first embodiment. The second protective film 42 suppresses the intrusion of mobile ions within the sealing resin into the first low-stress insulating film 51 and the second low-stress insulating film 52. Furthermore, the mobile ions are isolated from the semiconductor portion 10 and the termination insulating film 31 by the thick first low-stress insulating film 51 and the second low-stress insulating film 52 covered by the second protective film 42.

[0097] Since the metal film 61 does not allow mobile ions to pass through, it effectively suppresses the intrusion of mobile ions. In addition, since the metal film 61 is provided between the first low-stress insulating film 51 and the second protective film 42, even if a crack occurs at the corner C3 of the second protective film 42, the metal film 61 located inside will suppress the intrusion of mobile ions.

[0098] Hereinafter, the method for manufacturing the semiconductor device 102 of the present embodiment will be described with respect to only the differences from the first embodiment.

[0099] For example, similarly to the first embodiment, the first low-stress insulating film 51 and the second low-stress insulating film 52 are formed on the second electrode 22 , the terminal electrode 29 , and the first protective film 41 by plasma CVD.

[0100] The metal film 61 is formed on the first low-stress insulating film 51 by, for example, sputtering.

[0101] The metal member 62 is formed by laminating plating layers made of a metal including copper, for example.

[0102] Next, the effects of the semiconductor device 102 according to this embodiment will be described.

[0103] In the semiconductor device 102 of this embodiment, a metal film 61 is provided on the first low-stress insulating film 51. The front end portion 61bb of the metal film 61 overlaps and isolates the front end portion 61bb of the terminal electrode 29. Furthermore, the electrode contact portion 61e of the metal film 61 is connected to the second electrode 22. Thus, the front end portion 61bb of the metal film 61, sandwiched between the upper portion 51b of the first low-stress insulating film 51 and the main portion 29a of the terminal electrode 29, forms a capacitor C connected in parallel with the second electrode 22 and the second semiconductor layer 12. Therefore, the capacitor C can absorb electrical oscillations in the second electrode 22 and the second semiconductor layer 12 during reverse recovery after the switch is turned off. Consequently, the semiconductor device 102 can incorporate a reliable capacitor C at low cost.

[0104] Furthermore, a thick second low-stress insulating film 52 is provided on the terminal side of the first low-stress insulating film 51 and is disposed on the first protective film 41 and the terminal electrode 29. The second protective film 42 is provided over the first low-stress insulating film 51, the upper surface 29B of the terminal electrode 29, and the second low-stress insulating film 52. This arrangement provides a thick insulating film even at the terminal where negative mobile ions are likely to accumulate within the sealing resin, effectively suppressing a decrease in withstand voltage and inhibiting the intrusion of mobile ions.

[0105] Furthermore, the second protection film 42 , the first low-stress insulating film 51 , and the second low-stress insulating film 52 suppress discharge from the front end portion 61 bb of the metal film 61 to the terminal electrode 29 .

[0106] Furthermore, the metal member 62 is provided on the second electrode 22. The upper surface of the substantially rectangular parallelepiped metal member 62 is positioned above the second protective film 42. Thus, the metal member 62 uniformizes the thickness within the semiconductor device 102, mitigating stress within the semiconductor device 102. Furthermore, the overlapping portion of the metal member 62, the second electrode 22, the semiconductor portion 10, and the first electrode 21 is highly strong and can withstand external loads, thereby suppressing damage to the semiconductor device 102 caused by such external loads. Furthermore, the metal member 62 and the first electrode 21 are connected to a heat dissipation substrate, thereby enhancing heat dissipation.

[0107] The configuration, operation, and effects other than those described above in this embodiment are the same as those in the first embodiment.

[0108] (Third embodiment)

[0109] The semiconductor device 103 of this embodiment is an IGBT, and its cell region CE3 is different from the cell region CE of the semiconductor device 101 of the first embodiment, while its termination region EN3 is substantially the same as the termination region EN1 of the semiconductor device 101 .

[0110] Figure 6 It is an enlarged cross-sectional view showing the semiconductor device 103 according to this embodiment. Figure 6 is with Figure 3 Cross-sectional view of the same part, omitting the wiring layer.

[0111] like Figure 6 As shown, in the cell region CE3 and the termination region EN3, the semiconductor device 103 includes a fifth semiconductor layer 15 on the first electrode 21 and a lower semiconductor layer 11a on the fifth semiconductor layer 15. The fifth semiconductor layer 15 is of the second conductivity type, for example, a p-type semiconductor.

[0112] The semiconductor device 103 further includes a plurality of channel layers 17 , an emitter layer 18 a , an emitter contact layer 18 b , an insulating layer 32 , a gate electrode 24 , and a gate insulating film 24 a in the cell region CE3 .

[0113] The first electrode 21 is, for example, a collector electrode, and is connected to the positive side of the power supply device when disconnected. A predetermined voltage is applied to the gate electrode 24 for current control. The second electrode 22E is, for example, an emitter electrode. The second electrode 22E is connected to the negative side of the power supply device when disconnected. The second electrode 22E has a main body 22Ea provided on the semiconductor portion 10, and an end portion 22Eb located on the terminal side TS of the main body 22Ea. The main body 22Ea has a contact portion 22Ea1 extending downward on its lower surface. The contact portion 22Ec is in contact with the emitter contact layer 18b. The end portion 22Eb is provided on the first protective film 41 on the cell side CS of the terminal region EN3. A first low-stress insulating film 51 and a second protective film 42 are provided on the end portion 22Eb. The second protective film 42 is provided on the main body 22Ea.

[0114] like Figure 6 As shown, the emitter contact layers 18 b and the gate electrodes 24 are alternately arranged along an arrangement direction D1 toward the termination side TS, and extend along an extension direction D2 perpendicular to the arrangement direction D1 .

[0115] The channel layer 17 is composed of, for example, a p-type semiconductor, and the emitter layer 18a is composed of, for example, an n-type semiconductor. The emitter contact layer 18b is composed of, for example, a p-type semiconductor. + The gate electrode 24 is composed of a semiconductor and is provided so as to extend downward within the stacked channel layer 17 and emitter layer 18a. The gate electrode 24 is covered with a gate insulating film 24a except for its upper surface. The gate electrodes 24 arranged on the terminal side TS face the second semiconductor layer 12E via the gate insulating film 24a. The other gate electrodes 24 face the stacked upper semiconductor layer 11b, channel layer 17, and emitter layer 18a via the gate insulating film 24a. An insulating layer 32 is provided between the second electrode 22E and the gate electrode 24.

[0116] According to the semiconductor device 103 of this embodiment, even if the semiconductor device 103 is, for example, an IGBT, by arranging the main body 22Ea of the second electrode 22E on the semiconductor portion 10 and arranging the end 22Eb of the second electrode 22E on the first protective film 41 of the terminal area EN3, the same terminal structure as that of the semiconductor device 101 of the first embodiment and the semiconductor device 102 of the second embodiment can be adopted, thereby improving the reliability of the semiconductor device 103.

[0117] The configuration, operation, and effects other than those described above in this embodiment are the same as those in the first embodiment.

[0118] According to the embodiment of the present invention, a highly reliable semiconductor device can be provided.

[0119] The embodiments of the present invention have been described above with reference to specific examples. However, the embodiments of the present invention are not limited to these specific examples. For example, regarding the specific configuration of the cell region or terminal region contained in the semiconductor device, the semiconductor layer constituting the semiconductor portion, the specific shape or material of the electrode, etc., as long as a person skilled in the art can implement the present invention in the same manner and obtain the same effect by making appropriate selections from the known range, they are included in the scope of the present invention. Combining any two or more elements of each specific example within the technically possible range is also included in the scope of the present invention as long as it contains the gist of the present invention.

[0120] While several embodiments of the present invention have been described, these embodiments are provided as examples and are not intended to limit the scope of the invention. These novel embodiments may be implemented in various other ways, and various omissions, substitutions, and modifications may be made without departing from the spirit of the invention. These embodiments and their variations are intended to be within the scope and spirit of the invention and are encompassed by the invention as set forth in the claims and their equivalents.

[0121] The present invention includes the following aspects.

[0122] (Note 1)

[0123] A semiconductor device is provided with a cell region and a terminal region surrounding the cell region, wherein the semiconductor device comprises:

[0124] a first electrode;

[0125] a semiconductor portion, disposed on the first electrode;

[0126] a terminal insulating film provided on the semiconductor portion in the terminal region;

[0127] A first protective film, provided on the terminal insulating film, comprising silicon and nitrogen;

[0128] a second electrode provided on the semiconductor portion in the cell region, wherein an end portion of the second electrode is disposed on the first protective film;

[0129] a terminal electrode provided on the first protective film in the terminal region and connected to the semiconductor portion;

[0130] a first low-stress insulating film provided on the first protective film and in contact with an end portion of the second electrode and the terminal electrode, wherein a lower portion of the first low-stress insulating film is disposed between the second electrode and the terminal electrode, and an upper portion of the first low-stress insulating film is disposed above the second electrode and the terminal electrode, the first low-stress insulating film containing hydrogen and having an internal stress lower than that of the terminal insulating film; and

[0131] The second protection film covers the upper portion of the first low-stress insulating film and includes silicon and nitrogen.

[0132] (Note 2)

[0133] The semiconductor device as described in Supplementary Note 1,

[0134] The first low-stress insulating film further contains silicon, oxygen, nitrogen, and hydrogen.

[0135] (Note 3)

[0136] The semiconductor device according to Supplementary Note 1 or 2,

[0137] The second protection film is in contact with the terminal electrode.

[0138] (Note 4)

[0139] The semiconductor device according to any one of Supplementary Notes 1 to 3,

[0140] The second protection film is in contact with the first protection film at a terminal side relative to the terminal electrode.

[0141] (Note 5)

[0142] The semiconductor device as described in Supplementary Note 4,

[0143] An angle formed between the upper surface of the terminal electrode and the side surface on the terminal side is greater than 100 degrees.

[0144] (Note 6)

[0145] The semiconductor device according to any one of Supplementary Notes 1 to 5,

[0146] An angle formed between a side surface and an upper surface of the upper portion of the first low-stress insulating film is greater than or equal to 100 degrees.

[0147] (Note 7)

[0148] The semiconductor device according to any one of Supplementary Notes 1 to 6,

[0149] The second protection film is in contact with the second electrode.

[0150] (Note 8)

[0151] The semiconductor device according to any one of Supplementary Notes 1 to 7,

[0152] The semiconductor device further includes a metal film, the metal film being provided on the first low-stress insulating film and connected to the second electrode, a portion of the metal film overlapping the terminal electrode and being isolated from the terminal electrode.

[0153] The semiconductor portion has:

[0154] a first semiconductor layer of a first conductivity type connected to the first electrode and the terminal electrode; and

[0155] A second semiconductor layer of a second conductivity type is provided on the first semiconductor layer in the cell region and is connected to the second electrode.

[0156] (Note 9)

[0157] The semiconductor device as described in Supplementary Note 8,

[0158] The semiconductor device further includes a second low-stress insulating film, the second low-stress insulating film being provided on a terminal side of the first low-stress insulating film, the lower portion of the second low-stress insulating film being arranged on the first protective film, the upper portion of the second low-stress insulating film being arranged on the terminal electrode, the second low-stress insulating film containing hydrogen,

[0159] The second protection film is also provided on the upper portion of the second low-stress insulating film.

[0160] (Note 10)

[0161] The semiconductor device as described in Supplementary Note 9,

[0162] An angle formed between the upper surface of the upper portion of the second low-stress insulating film and the side surface on the cell region side is greater than 100 degrees.

[0163] The second protection film is also provided on the upper surface and the side surfaces of the second low-stress insulating film.

[0164] (Note 11)

[0165] The semiconductor device according to any one of Supplementary Notes 1 to 10,

[0166] The semiconductor device further includes a metal component provided on the second electrode.

[0167] The upper surface of the metal member is located above the second protection film.

[0168] (Note 12)

[0169] The semiconductor device according to any one of Supplementary Notes 1 to 11,

[0170] The internal stress of the first low-stress insulating film is less than or equal to one-fortieth of the internal stress of the first protective film.

[0171] (Note 13)

[0172] The semiconductor device according to any one of Supplementary Notes 1 to 12,

[0173] The thickness of the upper portion of the first low-stress insulating film is greater than or equal to 5 μm and less than or equal to 40 times the thickness of the first protective film.

[0174] (Note 14)

[0175] The semiconductor device according to any one of Supplementary Notes 1 to 13,

[0176] The termination insulating film includes silicon and oxygen.

[0177] (Note 15)

[0178] A semiconductor device is provided with a cell region and a terminal region surrounding the cell region, wherein the semiconductor device comprises:

[0179] a first electrode;

[0180] a semiconductor portion, disposed on the first electrode;

[0181] a terminal insulating film provided on the semiconductor portion in the terminal region;

[0182] A first protective film, provided on the terminal insulating film, comprising silicon and nitrogen;

[0183] a second electrode provided on the semiconductor portion in the cell region, with an end portion of the second electrode being disposed on the first protection film;

[0184] a terminal electrode provided on the first protective film in the terminal region and connected to the semiconductor portion;

[0185] a first low-stress insulating film provided on the first protective film and in contact with an end portion of the second electrode and the terminal electrode, wherein a lower portion of the first low-stress insulating film is disposed between the second electrode and the terminal electrode, and an upper portion of the first low-stress insulating film is disposed above the second electrode and the terminal electrode;

[0186] a second protective film covering the upper portion of the first low-stress insulating film, comprising silicon and nitrogen; and

[0187] A metal film is provided on the first low-stress insulating film and connected to the second electrode, wherein a portion of the metal film overlaps with the terminal electrode and is isolated from the terminal electrode.

Claims

1. A semiconductor device comprising a cell region and a terminal region surrounding the cell region, wherein: The semiconductor device comprises: a first electrode; a semiconductor portion, disposed on the first electrode; a terminal insulating film provided on the semiconductor portion in the terminal region; A first protective film, provided on the terminal insulating film, comprising silicon and nitrogen; a second electrode provided on the semiconductor portion in the cell region, with an end portion disposed on the first protective film; a terminal electrode provided on the first protective film in the terminal region and connected to the semiconductor portion; a first insulating film disposed on the first protective film and in contact with an end portion of the second electrode and the terminal electrode, wherein a lower portion of the first insulating film is disposed between the second electrode and the terminal electrode, and an upper portion of the first insulating film is disposed above the second electrode and the terminal electrode, the first insulating film containing hydrogen; as well as The second protection film covers the upper portion of the first insulating film and contains silicon and nitrogen.

2. The semiconductor device according to claim 1, wherein The first insulating film further contains silicon, oxygen, and nitrogen.

3. The semiconductor device according to claim 1 or 2, wherein The second protection film is in contact with the terminal electrode.

4. The semiconductor device according to claim 1 or 2, wherein The second protection film is in contact with the first protection film at a terminal side relative to the terminal electrode.

5. The semiconductor device according to claim 1 or 2, wherein The second protection film is in contact with the second electrode.

6. The semiconductor device according to claim 1 or 2, wherein The semiconductor device further includes a metal film provided on the first insulating film and connected to the second electrode, wherein a portion of the metal film overlaps the terminal electrode and is isolated from the terminal electrode. The semiconductor portion has: a first semiconductor layer of a first conductivity type connected to the first electrode and the terminal electrode; as well as A second semiconductor layer of a second conductivity type is provided on the first semiconductor layer in the cell region and is connected to the second electrode.

7. The semiconductor device according to claim 6, wherein The semiconductor device further includes a second insulating film, the second insulating film being provided on the terminal side of the first insulating film, the lower portion of the second insulating film being arranged on the first protective film, the upper portion of the second insulating film being arranged on the terminal electrode, the second insulating film containing hydrogen. The second protection film is also provided on the upper portion of the second insulating film.

8. The semiconductor device according to claim 1 or 2, wherein The semiconductor device further includes a metal component provided on the second electrode. The upper surface of the metal member is located above the second protection film.

9. A semiconductor device comprising a cell region and a terminal region surrounding the cell region, wherein: The semiconductor device comprises: a first electrode; a semiconductor portion, disposed on the first electrode; a terminal insulating film provided on the semiconductor portion in the terminal region; A first protective film, provided on the terminal insulating film, comprising silicon and nitrogen; a second electrode provided on the semiconductor portion in the cell region, with an end portion disposed on the first protective film; a terminal electrode provided on the first protective film in the terminal region and connected to the semiconductor portion; a first insulating film provided on the first protective film and in contact with an end portion of the second electrode and the terminal electrode, wherein a lower portion of the first insulating film is disposed between the second electrode and the terminal electrode, and an upper portion of the first insulating film is disposed above the second electrode and the terminal electrode, the first insulating film containing hydrogen; a second protective film covering the upper portion of the first insulating film and comprising silicon and nitrogen; The metal film is provided on the first insulating film and connected to the second electrode, wherein a portion of the metal film overlaps with the terminal electrode and is isolated from the terminal electrode.

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