Semiconductor Device

Abstract

To provide a semiconductor device with a reduced chip size while suppressing electric field concentration.SOLUTION: A semiconductor device does not include a connection portion that connects main portions 12a above a main portion 11a, above a main portion 12a of a drain electrode, and below an insulating film that covers a main portion 13a outside a first connection portion 13b connecting the main portions 13a of control electrodes (gate electrodes) adjacent to each other with the main portion 11a of the source electrode interposed therebetween, and adjacent main portions 12a are electrically connected to each other via a connection wiring provided on the insulating film.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a semiconductor device, and more particularly to a semiconductor device having a plurality of main electrodes on a semiconductor substrate and a control electrode between the plurality of main electrodes. [Background technology]

[0002] A comb-shaped structure in which a source electrode and a drain electrode are intertwined on a semiconductor substrate is adopted as the electrode structure of a transistor. In this transistor electrode structure, a comb-shaped source electrode, a comb-shaped drain electrode, and a control electrode that controls the current flowing between them are arranged. In order to improve the breakdown voltage of a lateral semiconductor device having such an interdigitated electrode structure, various structures have been proposed. For example, a structure has been proposed in which the distance between the electrodes at the tips of the comb electrodes is wider than the distance between the electrodes at the straight parts of the electrodes, thereby mitigating electric field concentration at the tips of the electrodes (see, for example, Patent Document 1). Also proposed is a structure that includes a comb-shaped source electrode, a comb-shaped drain electrode arranged in an interdigital fashion with the source electrode, and a gate electrode arranged between the source electrode and the drain electrode 20, in which the radius of curvature of the curved portion of the gate electrode extending along the tip portion of the source electrode is larger at the outermost tip portion of the source electrode than at other tip portions of the source electrode (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-98222 A [Patent Document 2] JP 2017-147264 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, increasing the radius of curvature of the gate electrode increases the size of the semiconductor device.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a semiconductor device in which the chip size is reduced while suppressing electric field concentration. [Means for solving the problem]

[0006] In order to solve the above problems, a semiconductor device according to one or more embodiments includes a semiconductor substrate, a first main electrode provided on the semiconductor substrate and extending in a first direction, a connection portion of the first main electrode provided on the semiconductor substrate and extending in a second direction different from the first direction, the connection portion of the first main electrode connecting one ends of adjacent first main electrodes, a second main electrode provided on the semiconductor substrate and extending in the first direction away from the first main electrode, a control electrode provided on the semiconductor substrate and formed between the first main electrode and the second main electrode, and a control electrode provided on the semiconductor substrate and connecting the first main electrode and the second main electrode. The semiconductor device is characterized by having a first connection portion of the control electrode that is outside the other end of the electrode and connects one end of adjacent control electrodes, a second connection portion of the control electrode that is provided on a semiconductor substrate and connects the other ends of adjacent control electrodes between the connection portion of the first main electrode and the second main electrode, an insulating film provided on the first main electrode, the second main electrode, and the control electrode, and a connection portion that connects adjacent second main electrodes outside the first connection portion is not provided under the insulating film, and adjacent second main electrodes are electrically connected via a connection wiring provided on the insulating film. Effect of the Invention

[0007] According to the above configuration, it is possible to provide a semiconductor device in which the chip size is reduced while suppressing electric field concentration. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view of a semiconductor device according to one or more embodiments. [Diagram 2]FIG. 2 is a modified plan view of a semiconductor device according to one or more embodiments. [Diagram 3] FIG. 3 is a cross-sectional view of a semiconductor device according to one or more embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] With reference to the drawings, one or more embodiments will be described in detail. In the following description of the drawings, the same or similar parts may be given the same or similar reference numerals. The description of the drawings is schematic, and the relationship between thickness and dimensions, the ratio of thickness of each layer, etc. are only examples, and do not limit the technical idea of ​​the invention. In addition, the relationship and ratio of dimensions may differ between drawings. In the following embodiment, the first conductivity type is n-type and the second conductivity type is p-type as an example, but the conductivity types may be selected in reverse, and the first conductivity type may be p-type and the second conductivity type may be n-type. In the following description, when describing the positional relationship of the members, the terms "upper", "lower", "right side", "left side", etc. are used as necessary based on the orientation of the drawings to be referred to, but do not limit the technical idea of ​​the invention. In addition, the terms "upper", "lower", "right side", "left side", etc. may be used even when the members are not in contact.

[0010] 1 is a plan view of a semiconductor device 1. In the semiconductor device 1, a first main electrode, such as a source electrode 11, and a second main electrode, such as a drain electrode 12, are formed on a semiconductor substrate 10. Furthermore, a control electrode 13 that controls a current flowing between the source electrode 11 and the drain electrode 12 is formed on the semiconductor substrate 10.

[0011] The semiconductor substrate 10 is made of, for example, a nitride-based semiconductor, and a well-known two-dimensional electron gas layer is generated within the semiconductor substrate 10. The source electrode 11 and the drain electrode 12 are connected to the two-dimensional electron gas layer through low resistance connections, and the two-dimensional electron gas layer is controlled by a control electrode 13 to turn the semiconductor device on and off.

[0012] The source electrode 11 has a main portion 11a and a connection portion 11b. The main portion 11a of the source electrode 11 extends in one direction, and one ends of the main portions 11a of adjacent source electrodes 11 are connected to each other via a connection portion 11b extending in the other direction that intersects the one direction. The other end of the main portion 11a of the source electrode 11 does not have a connection portion and serves as the end of the source electrode 11.

[0013] The drain electrode 12 has a main portion 12a extending in one direction. The width (width y in FIG. 1) of the main portion 12a of the drain electrode 12 is wider than the width (width x in FIG. 1) of the main portion 11a of the source electrode 11. At both ends of the main portion 12a of the drain electrode 12, no connection portion for connecting the main portions 12a of adjacent drain electrodes 12 is formed on the semiconductor substrate, and adjacent drain electrodes 12 are connected through a through hole in an insulating film formed above the drain electrode 12 and a wiring formed on the insulating film.

[0014] The main portion 13a of the control electrode (gate electrode) 13 extends in one direction. The main portions 13a of adjacent control electrodes (gate electrode) 13 sandwiching the main portion 11a of the source electrode 11 are connected by a first connection portion 13b from outside the other end of the main portion 11a of the source electrode 11. The first connection portion 13b is provided on the semiconductor substrate 1. The main portions 13a of adjacent control electrodes (gate electrode) 13 sandwiching the main portion 12a of the drain electrode 12 connect the connection portion 11b of the source electrode 11 and the drain electrode 12 by a second connection portion 13c. The second connection portion 13c is provided on the semiconductor substrate 1.

[0015] According to the semiconductor device 1, since the connection portion of the drain electrode 12 is not provided on the semiconductor substrate 2, it is possible to prevent the chip size of the semiconductor substrate 2 from becoming large. In addition, although the curvature of the first connection portion 13b of the control electrode (gate electrode) 13 becomes large, since the connection portion of the drain electrode 12 is not provided so as to face the connection portion 13b, it becomes easier to ensure the distance between the control electrode (gate electrode) 13 and the drain electrode 12, and electric field concentration can be suppressed.

[0016] In addition, the distance from the main portion 11a of the source electrode 11 to the main portion 13a of the control electrode (gate electrode) 13 is shorter than the distance from the main portion 13a of the control electrode (gate electrode) 13 to the main portion 12a of the drain electrode 12. It is desirable that the curvature of the first connection portion 13b is larger than the curvature of the second connection portion 13c. This can mitigate the electric field concentration at the first connection portion 13b. If the connection portion of the drain electrode 12 is provided outside the first connection portion 13b, the connection portion of the drain electrode 12 must be moved outward or the pattern must be changed according to the curvature, which would increase the chip size. However, since the semiconductor device 1 does not have the connection portion of the drain electrode 12 on the semiconductor substrate 2, it is possible to suppress the increase in the chip size of the semiconductor substrate 2 while suppressing the electric field concentration.

[0017] It is also desirable that the dimension in one direction of the main portion 11a of the source electrode 11 is longer than the dimension in one direction of the main portion 12a of the drain electrode 12, and the other end of the main portion 11a of the source electrode 11 protrudes (protrudes by the dimension z in FIG. 2) from the end of the main portion 12a of the drain electrode 12. Since no connection portion of the drain electrode 12 is provided on the semiconductor substrate 2, by making it protrude, the first connection portion 13b of the control electrode (gate electrode) 13 is moved outward, and the distance between the first connection portion 13b of the control electrode (gate electrode) 13 and the end of the main portion 12a of the drain electrode 12 can be further secured.

[0018] One or more of the above-described embodiments are not limited to nitride semiconductors, but may be applied to semiconductor devices including semiconductor substrates made of other semiconductor materials, such as silicon or silicon carbide.

[0019] Although the embodiments have been described above, the descriptions and drawings forming part of this disclosure do not limit the present invention, and various alternative embodiments, examples, and operation techniques will become apparent to those skilled in the art. Thus, the present invention includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined by the invention-specific matters related to the appropriate claims from the above description. [Industrial Applicability]

[0020] The invention is particularly applicable to power semiconductor devices. [Explanation of symbols]

[0021] 1 Semiconductor device 10. Semiconductor Substrate 11 Source electrode 12 Drain electrode 13 Control electrode

Claims

1. A semiconductor substrate; a first main electrode provided on the semiconductor substrate and extending in a first direction; a first main electrode connection portion provided on the semiconductor substrate, extending in a second direction different from the first direction, and connecting one ends of adjacent first main electrodes to each other; a second main electrode provided on the semiconductor substrate and extending in a first direction and spaced apart from the first main electrode; a control electrode provided on the semiconductor substrate and formed between the first main electrode and the second main electrode; a first connection portion of the control electrode that is provided on the semiconductor substrate and is located outside the other end of the first main electrode and connects one ends of adjacent control electrodes to each other; a second connection portion of the control electrode provided on a semiconductor substrate and connecting the other ends of adjacent control electrodes between the connection portion of the first main electrode and the second main electrode; an insulating film provided on the first main electrode, the second main electrode, and the control electrode; A semiconductor device characterized in that it does not have a connection portion under the insulating film that connects adjacent second main electrodes to each other outside the first connection portion, and adjacent second main electrodes are electrically connected via a connection wiring provided on the insulating film.

2. 2. The semiconductor device according to claim 1, wherein the length of the second main electrode in the first direction is shorter than the length of the first main electrode in the first direction.

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