Semiconductor Devices

Abstract

The present invention discloses a semiconductor device, including a substrate, a buffer member, a frame, a cover and a semiconductor element. A ceramic frame is mounted on a copper substrate, and a molybdenum buffer member is placed between the ceramic frame and the copper substrate. The semiconductor element is sealed in a space within the frame defined by the cover. The frame includes: a top; a lower section, which is arranged below the top and is provided with an input electrode and an output electrode; and an upper section. The upper section is formed in the arrangement direction of the input electrode and the output electrode, and is formed below the top and above the lower section. The upper section includes an upper section connecting portion, which is formed on the periphery of the lower section in a direction intersecting with the arrangement direction of the input electrode and the output electrode.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2018-130920, filed on Jul. 10, 2018, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a semiconductor device. Background Art

[0004] Semiconductor devices are installed in, for example, communication devices. The semiconductor device includes a copper substrate and a ceramic frame mounted on the substrate, and its semiconductor element is sealed in a space formed by the frame. Because the copper substrate and the ceramic frame have different linear expansion coefficients, cracks may be generated in the frame due to the difference in linear expansion coefficients. JPS59-161845 discloses a structure that prevents cracks from being generated in the frame by inserting a buffer member (molybdenum plate) formed of molybdenum between the substrate (package substrate) and the frame (housing). Summary of the invention

[0005] The present disclosure provides a semiconductor device. The semiconductor device includes a substrate, a buffer member, a frame, a cover and a semiconductor element. The substrate is formed of copper. The buffer member is formed of molybdenum. The frame is mounted on the substrate, and the buffer member is placed between the frame and the substrate, and the frame is formed of alumina ceramic. The cover covers the frame. The semiconductor element is sealed in a space within the frame defined by the cover. The frame includes a top, a lower section and an upper section. The top includes a sealing ring, and the cover is fixed to the sealing ring. The lower section is arranged below the top, and the lower section is provided with an input electrode for inputting a signal to the semiconductor element and an output electrode for outputting a signal from the semiconductor element. The upper section is formed in the arrangement direction of the input electrode and the output electrode, and is formed at a position below the top and above the lower section. The upper section includes an upper section connecting portion, which is formed on the periphery of the lower section in a direction intersecting with the arrangement direction of the input electrode and the output electrode.

[0006] The present disclosure also provides a semiconductor device. The semiconductor device includes a substrate, a buffer member, a frame, a cover and a semiconductor element. The substrate is formed of copper. The buffer member is formed of molybdenum. The frame is mounted on the substrate, and the buffer member is placed between the frame and the substrate, and the frame is formed of alumina ceramic. The cover covers the frame. The semiconductor element is sealed in a space within the frame defined by the cover. The frame includes a top, a lower section and an upper section. The top includes a sealing ring, and the cover is fixed to the sealing ring. The lower section is arranged below the top. The lower section is provided with an input electrode for inputting a signal to the semiconductor element and an output electrode for outputting a signal from the semiconductor element. The lower section includes a reinforcing metal pattern, which is arranged on the same plane as the plane of the output electrode, at a position where the input electrode and the output electrode are not arranged, so as to be insulated from the input electrode and the output electrode. The upper section is formed in the arrangement direction of the input electrode and the output electrode, and is formed at a position below the top and above the lower section. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The above and other objects, aspects and advantages will be better understood from the following detailed description of embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0008] Figure 1A and Figure 1B is a view for illustrating a semiconductor device according to an embodiment of the present disclosure.

[0009] Figure 2 is an external perspective view of the frame of the first example.

[0010] Figure 3A is a plan view of a main portion of a semiconductor device of a first example, Figure 3B It is along Figure 3A Cross-sectional view taken along line BB.

[0011] Figure 4A is a plan view of a main portion of a semiconductor device of a second example, Figure 4B It is along Figure 4A Cross-sectional view taken along line BB. DETAILED DESCRIPTION

[0012] [Problems to be solved by the present disclosure]

[0013] The frame described in JP S59-161845 includes: a top (upper part of the frame) whose upper side is covered by a cover and the cover is fixed to the top; and a lower section (lower part of the frame) which is arranged on the lower section relative to the top. In the frame, a step is formed between the top and the lower section, and an electrode plate wire-bonded to a semiconductor element is arranged on the upper surface of the step. Due to the difference in thickness between the top and the lower section, deformation is concentrated at the boundary between the top and the lower section, so cracks may be generated in the lower section.

[0014] [Effects of the present disclosure]

[0015] According to the present disclosure, it is possible to prevent cracks from being generated in the lower stage portion of the frame.

[0016] [Description of Embodiments of the Present Disclosure]

[0017] An embodiment of the present disclosure will be described. A semiconductor device according to an embodiment of the present disclosure includes a substrate, a buffer member, a frame, a cover, and a semiconductor element. The substrate is formed of copper. The buffer member is formed of molybdenum. The frame is mounted on the substrate, and the buffer member is placed between the frame and the substrate, and the frame is formed of alumina ceramic. The cover covers the frame. The semiconductor element is sealed in a space within the frame defined by the cover. The frame includes a top, a lower section, and an upper section. The top includes a sealing ring, and the cover is fixed to the sealing ring. The lower section is arranged below the top, and is provided with an input electrode for inputting a signal to the semiconductor element and an output electrode for outputting a signal from the semiconductor element. The upper section is formed in the arrangement direction of the input electrode and the output electrode, and is formed at a position below the top and above the lower section. The upper section includes an upper section connection portion, which is formed on the periphery of the lower section along a direction intersecting with the arrangement direction of the input electrode and the output electrode.

[0018] A semiconductor device according to another embodiment of the present disclosure includes a substrate, a buffer member, a frame, a cover, and a semiconductor element. The substrate is formed of copper. The buffer member is formed of molybdenum. The frame is mounted on the substrate, and the buffer member is placed between the frame and the substrate, and the frame is formed of alumina ceramic. The cover covers the frame. The semiconductor element is sealed in a space within the frame defined by the cover. The frame includes a top, a lower section, and an upper section. The top includes a sealing ring to which the cover is fixed. The lower section is arranged below the top. The lower section is provided with an input electrode for inputting a signal to the semiconductor element and an output electrode for outputting a signal from the semiconductor element. The lower section includes a reinforcing metal pattern, which is arranged at a position where the input electrode and the output electrode are not arranged on the same plane as the plane of the output electrode, so as to be insulated from the input electrode and the output electrode. The upper section is formed in the arrangement direction of the input electrode and the output electrode, and is formed at a position below the top and above the lower section.

[0019] In the above another embodiment, the lower stage may include a frame opening surrounding the periphery of the semiconductor element. The frame opening may be provided with a reinforcing metal pattern, and the reinforcing metal pattern may be a ground (GND) wiring electrically connected to the base through the buffer member.

[0020] [Details of Embodiments of the Present Disclosure]

[0021] Hereinafter, detailed examples of a semiconductor device according to the present disclosure will be described with reference to the accompanying drawings. Figure 1A and Figure 1B 2 is a view for illustrating a semiconductor device according to an embodiment of the present disclosure.

[0022] The semiconductor device 100 includes a base 1, a buffer member 20, a frame 30, a cover 70, and a semiconductor element 90. For example, the semiconductor device 100 can be mounted on the front end of a communication device. By separating the cover 70, Figure 1A The semiconductor element 90 mounted within the frame 30 is schematically shown.

[0023] like Figure 1A As shown in FIG. 1 , the substrate 1 includes a substrate body 10 formed of copper. Both ends of the substrate body 10 are provided with screw fixing portions 11, through which fixing screws (not shown) are inserted. A heat sink 12 is provided between the screw fixing portions 11, and the heat sink 12 is thinner than the screw fixing portions 11. Figure 1B As shown in FIG. 1 , a central portion of the heat sink 12 is provided with a mounting stage 13 protruding upward (in the Z direction in the figure), and a semiconductor element 90 is mounted on the mounting stage 13 .

[0024] The buffer member 20 is formed of molybdenum and compensates for the difference in linear expansion coefficient between the base body 10 formed of copper and the frame 30 formed of alumina ceramics. Figure 1B As shown in the figure, the buffer member 20 includes a plate-shaped buffer portion 22, and a buffer opening 21 is provided at the center of the buffer portion 22, and the buffer opening 21 penetrates the front surface 22b and the rear surface 22a. The mounting table 13 penetrates the buffer opening 21, the rear surface 22a of the buffer portion 22 contacts the base body 10, and the front surface 22b of the buffer portion 22 contacts the frame 30.

[0025] The frame 30 is surrounded by four side walls extending in the X and Y directions shown in the figure, and is formed in a square shape in appearance when viewed from the front side. Figure 1B As shown in FIG. 1 , the frame 30 includes a lower section 40, an upper section 50, and a top 60. The lower section 40 is mounted on the buffer member 20. The upper section 50 is located at an upper side relative to the lower section 40. The top 60 is located at an upper side relative to the upper section 50 and is attached to the cover 70.

[0026] The cover 70 is formed of, for example, gold tin. The cover 70 is fixed to the top 60 with a seal ring 61 interposed between the cover 70 and the top 60. Thus, the semiconductor element 90 is sealed in a hermetically sealed manner in the space defined by the cover 70 within the frame 30.

[0027] Figure 2 is an external stereogram of the frame of the first example, Figure 3A is a plan view of a main portion of a semiconductor device of a first example, Figure 3B It is along Figure 3A Cross-sectional view taken along line BB. Figure 3A The mounting table 13 is shown to facilitate understanding of the structure of the frame 30, but is omitted. Figure 1A and Figure 1B The semiconductor component 90 or the base body 10 described in FIG.

[0028] The lower section 40 of the frame 30 includes a frame opening 41 and a step surface 42. The frame opening 41 is formed at the center to surround the mounting table 13. The step surface 42 is formed at the outer side of the frame opening 41 to surround the frame opening 41 over the entire circumference.

[0029] The step surface 42 is provided with an input electrode 43, which is provided between the input terminal 81 and the mounting table 13 so as to provide a Figure 1A and Figure 1BThe semiconductor element 90 described in the embodiment of the present invention inputs a signal. The input electrode 43 is wire-bonded to the semiconductor element 90. The output electrode 44 is provided between the output terminal 82 and the mounting stage 13 so as to output a signal from the semiconductor element 90. The output electrode 44 is wire-bonded to the semiconductor element 90. The input electrode 43 is formed to be wider than the output electrode 44.

[0030] In order to improve the airtightness inside the frame 30, the upper stage portion 50 of the frame 30 is formed to be higher than the step surface 42. The upper stage surface 52 is provided between the top portion 60 and the input electrode 43 and between the output electrode 44 and the top portion 60.

[0031] The upper section 50 includes a pair of upper section connection parts 53 formed in a direction (X direction of the drawing) intersecting with the arrangement direction (Y direction of the drawing) of the input electrode 43 and the output electrode 44. The pair of upper section connection parts 53 solves the height difference between the top 60 and the lower section 40. More specifically, the upper section connection parts 53 are formed along the inner wall of the frame 30 and formed on the periphery of the lower section 40 to become a step higher than the lower section 40. The upper section connection parts 53 are flush with, for example, the upper section surface 52. By changing the mold used to form the upper section 50, the upper section connection parts 53 can be easily manufactured.

[0032] The top 60 and the lower section 40 are positions where the thickness variation is greatest in the frame 30. When there is a large height difference between the top 60 and the lower section 40, when the semiconductor device is subjected to a heat cycle test of 50 cycles at -65°C to 175°C, cracks extending in a direction (X direction in the drawing) intersecting the arrangement direction (Y direction in the drawing) of the input electrode 43 and the output electrode 44 are generated in the step surface 42 starting from the boundary between the top 60 and the lower section 40 as the starting position. Such cracks are a factor causing leakage failure.

[0033] However, as described above, since the upper stage connection portion 53 is formed between the top portion 60 and the lower stage portion 40, it is possible to reduce the concentration of deformation generated at the boundary between the top portion 60 and the lower stage portion 40 due to the large height difference between the top portion 60 and the lower stage portion 40. Therefore, the semiconductor device 100 of this example can prevent cracks from being generated in the step surface 42.

[0034] In the above-described first example, there has been described an example in which the upper stage connection portion 53 is provided to resolve the large height difference between the top portion 60 and the lower stage portion 40. However, the present invention is not limited to this example.

[0035] Figure 4A is a plan view of a main portion of a semiconductor device of a second example, Figure 4B It is along Figure 4A Cross-sectional view taken along line BB.

[0036] like Figure 4A and Figure 4B As shown in FIG. 1 , the upper stage portion 50 of this example includes an upper stage surface 52 formed between the top portion 60 and the input electrode 43 and between the output electrode 44 and the top portion 60. Meanwhile, the step surface 42 of the lower stage portion 40 reaches the inner wall of the frame 30, and there is a large height difference between the top portion 60 and the lower stage portion 40.

[0037] However, the step surface 42 is provided with reinforcing metal patterns 45, which are respectively provided at positions where the input electrode 43 and the output electrode 44 are not provided and on the same plane as the plane of the output electrode 44. Each of the metal patterns 45 is formed by gold plating (for example, with a thickness of about 2.5 (μm)) and is insulated from the input electrode 43 and the output electrode 44. The reinforcing metal pattern 45 can be easily produced by the same steps as those of the output electrode 44.

[0038] Since the reinforcing metal pattern 45 is formed on the step surface 42 in this way, the concentration of deformation generated at the boundary between the top 60 and the lower stage 40 due to the large height difference between the top 60 and the lower stage 40 can be reduced in this example. Therefore, the semiconductor device 100 of this example can prevent cracks from being generated in the step surface 42.

[0039] In addition, if Figure 4B As shown in FIG. 4 , the frame opening 41 may be provided with a reinforcing metal pattern 46. In this case, the reinforcing metal pattern 46 is set as a ground wiring which is electrically connected to the base body 10 through the buffer member 20. Therefore, the strength of the lower stage 40 can be further improved.

[0040] Alternatively, the reinforcing metal pattern 47 may be provided in the inner wall of the frame 30 located on the outer side relative to the step surface 42. This example can improve the strength of the lower stage portion 40.

[0041] It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every aspect. The scope of the present invention is expressed by the scope of the claims rather than the scope of the above meaning. It is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A semiconductor device, comprising: a substrate formed of copper; a buffer member formed of molybdenum; a frame mounted on the base, with the buffer member interposed between the frame and the base, the frame being formed of alumina ceramics; a cover covering the frame; as well as a semiconductor element sealed in a space within the frame defined by the cover, The framework includes: a top portion, the top portion including a sealing ring to which the cover is secured; a lower section, the lower section being disposed below the top section, the lower section being provided with an input electrode for inputting a signal to the semiconductor element and an output electrode for outputting a signal from the semiconductor element; and An upper section, the upper section is formed in the arrangement direction of the input electrode and the output electrode, and the upper section is formed at a position below the top and above the lower section, wherein the upper section includes an upper section connecting portion, and the upper section connecting portion is formed on the periphery of the lower section in a direction intersecting with the arrangement direction of the input electrode and the output electrode.

2. A semiconductor device, comprising: a substrate formed of copper; a buffer member formed of molybdenum; a frame mounted on the base, with the buffer member interposed between the frame and the base, the frame being formed of alumina ceramics; a cover covering the frame; as well as a semiconductor element sealed in a space within the frame defined by the cover, The framework includes: a top portion, the top portion including a sealing ring to which the cover is secured; a lower section, the lower section being disposed below the top section, the lower section being provided with an input electrode for inputting a signal to the semiconductor element and an output electrode for outputting a signal from the semiconductor element, wherein the lower section includes a reinforcing metal pattern, the reinforcing metal pattern being disposed on the same plane as the plane of the output electrode at a position where the input electrode and the output electrode are not disposed so as to be insulated from the input electrode and the output electrode; and An upper stage portion is formed in an arrangement direction of the input electrode and the output electrode and is formed at a position below the top portion and above the lower stage portion.

3. The semiconductor device according to claim 2, wherein: The lower stage portion includes a frame opening that surrounds a periphery of the semiconductor element, the frame opening is provided with the reinforcing metal pattern, and the reinforcing metal pattern is a ground wiring that is electrically connected to the base through the buffer member.

4. A package comprising: a substrate formed of copper; a buffer member formed of molybdenum; as well as a frame, the frame being mounted on the base, and the buffer member being interposed between the frame and the base, the frame being formed of alumina ceramics, Wherein, the frame includes an input electrode for inputting a signal and an output electrode for outputting a signal, wherein the frame comprises a lower section, the lower section comprises an opening and a stepped surface, and Wherein, the input electrode and the output electrode are placed on the step surface of the lower section.

5. The package according to claim 4, wherein: The frame includes a first reinforcing metal pattern placed on the step surface of the lower stage.

6. The package according to claim 5, wherein: The frame includes a second reinforcing metal pattern, and the first reinforcing metal pattern and the second reinforcing metal pattern are respectively disposed at both ends of the output electrode.

7. The package according to claim 5, wherein: The first reinforcing metal pattern is a ground wiring electrically connected to the base through the buffer member.

8. A package comprising: a substrate formed of copper; a buffer member formed of molybdenum; as well as a frame, the frame being mounted on the base, and the buffer member being interposed between the frame and the base, the frame being formed of alumina ceramics, Wherein, the frame includes an input electrode for inputting a signal and an output electrode for outputting a signal, The framework also includes: a lower section, the lower section including an opening; and An upper section includes an opening portion that is larger than the opening portion of the lower section.

9. The package according to claim 8, wherein: The base includes a mounting platform that penetrates the opening of the lower section and the opening of the upper section.

10. A package comprising: a substrate formed of copper; a buffer member formed of molybdenum; a frame mounted on the base, with the buffer member interposed between the frame and the base, the frame being formed of alumina ceramics; as well as a cover covering the frame and defining a space in the frame, The frame includes an input electrode for inputting a signal and an output electrode for outputting a signal.

11. The package according to claim 10, wherein: The cap is formed of an alloy of gold and tin.

12. A package comprising: a substrate formed of copper; a buffer member formed of molybdenum; as well as a frame, the frame being mounted on the base, and the buffer member being interposed between the frame and the base, the frame being formed of alumina ceramics, Wherein, the frame includes an input electrode for inputting a signal and an output electrode for outputting a signal, The buffer member includes an opening disposed at the center thereof, and the base includes a mounting platform penetrating through the opening of the buffer member.

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