A BJT semiconductor device
By forming a polysilicon field effect structure on the base region of the BJT semiconductor device electrically communicates with the emission region, a potential difference attracts multiple impurities is formed, which solves the parasitic resistance problem of the base region and improves the current amplification coefficient.
Patent Information
- Application Number
- CN202111472250.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-12-06
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2041-12-06
AI Technical Summary
The base region of the BJT semiconductor device has parasitic resistance, resulting in uneven current in the emission region and reducing the current amplification coefficient.
By forming a polysilicon field effect structure on the base region and electrically communicating with the emission region, a potential difference is formed to attract multiple impurities and reduce parasitic resistance. The polycrystalline silicon field effect structure may be a closed ring, a strip, a spiral, etc., and the base area located below it forms a ring or a strip, and separates the emission area into multiple parts to improve the current collecting efficiency.
It effectively reduces the parasitic resistance of the base region and increases the current amplification coefficient of the BJT semiconductor device.
Smart Images
Figure CN114267726B_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of semiconductor integrated circuit manufacturing, and in particular to a BJT (Bipolar Junction Transistor) semiconductor device. Background Art
[0002] Figure 1 The cross-sectional structure diagram of a BJT semiconductor device in the related art is shown. Figure 1 It can be seen that the BJT semiconductor device includes three regions, namely the emitter region 110, the base region 120 and the collector region 130. The three electrodes derived from the three regions are called emitter e, base b and collector c respectively; the PN junction between the emitter region 110 and the base region 120 is called emitter junction 101, and the PN junction between the base region 120 and the collector region 130 is called collector junction 102.
[0003] However, due to the parasitic resistance in the base region 120 of the BJT semiconductor device, the base current flows laterally in the base region 120 portion directly below the emitter region 110, and a voltage drop is generated in the base region 120 portion where the resistance exists, which results in the potentials of various positions in the base region 120 directly below the emitter region 110 being inconsistent, with the potential at the edge of the emitter junction 101 being higher and the potential at the center of the emitter junction 101 being lower, that is, the current density at the edge around the emitter junction 101 being higher and the current density at the center being lower. In a BJT with a larger emitter region 110, the current is mainly concentrated in a circle around the emitter region 110 (e.g. Figure 1 The dotted box position shows that the current amplification factor of the BJT device is reduced. Summary of the invention
[0004] The present application provides a voltage regulator, which can improve the emitter current crowding effect of a BJT device.
[0005] In order to solve the technical problem described in the background technology, the present application provides a BJT semiconductor device, the BJT semiconductor device includes a semiconductor substrate, the semiconductor substrate includes:
[0006] A base region, on which a polysilicon field effect structure is formed;
[0007] An emitter region formed in a base region around the polysilicon field effect structure;
[0008] A collector region, the collector region surrounding the base region;
[0009] Wherein, the polysilicon field effect structure is electrically connected to the emitter region.
[0010] Optionally, the polysilicon field effect structure and the emitter region are electrically connected so that a potential difference is formed in the base region portion located below the polysilicon field effect structure, and the potential difference can attract majority impurities in the base region and reduce the parasitic resistance in the base region.
[0011] Optionally, a side surface of the emitter region is in contact with a base region portion below the polysilicon field effect structure.
[0012] Optionally, the polysilicon field effect structure is a closed ring, and the base region portion located below the closed ring-shaped polysilicon field effect structure forms a base region ring portion;
[0013] The base region ring portion divides the emitter region into a first emitter region portion and a second emitter region portion;
[0014] The first emitter region is in a closed ring shape, surrounding the base region ring portion;
[0015] The base region ring portion surrounds the second emitter region portion.
[0016] Optionally, the polysilicon field effect structure is in a strip shape; a portion of the base region located below the strip-shaped polysilicon field effect structure forms a base region strip portion;
[0017] The base strip portion divides the emitter region into a first emitter region portion and a second emitter region portion located at two sides of the base strip portion.
[0018] Optionally, the polysilicon field effect structure may be any one of spiral, tic-tac-toe, cross, field and other similar structures, and the shape of the base region below the polysilicon field effect structure is consistent with the shape of the polysilicon field effect structure.
[0019] Optionally, the polysilicon field effect structure includes a plurality of polysilicon field effect structure strips;
[0020] A plurality of polysilicon field effect structure strips are arranged in parallel or crosswise on the base region.
[0021] Optionally, the base region portion located below the polysilicon field effect structure is connected to other base region portions.
[0022] Optionally, the conductivity type of the majority impurities in the emitter region is the same as the conductivity type of the majority impurities in the collector region;
[0023] The conductivity type of the majority impurities in the base region is opposite to the conductivity type of the majority impurities in the emitter region, and the conductivity type of the majority impurities in the base region is opposite to the conductivity type of the majority impurities in the collector region.
[0024] The technical solution of the present application includes at least the following advantages: the present application forms a potential difference in the base region located below the polysilicon field effect structure through electrically connected polysilicon field effect structure and emitter region, and the potential difference can attract majority impurities in other base region parts, reduce the parasitic resistance in the base region, and can improve the current amplification factor of the BJT semiconductor device. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0026] Figure 1 A cross-sectional structural diagram of a BJT semiconductor device in the related art is shown;
[0027] Figure 2 A schematic diagram of a top view of a BJT semiconductor device provided in an embodiment of the present application is shown;
[0028] Figure 3 Shows Figure 2 AA longitudinal section structural diagram;
[0029] Figure 4 A schematic diagram of a top view of a BJT semiconductor device provided in another embodiment of the present application is shown;
[0030] Figure 5 A schematic diagram of the top view of the structure of a BJT semiconductor device provided in another embodiment of the present application is shown. DETAILED DESCRIPTION
[0031] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0032] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.
[0033] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can also be the internal connection of two components, it can be a wireless connection, or it can be a wired connection. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0034] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.
[0035] Figure 2 FIG. 1 shows a schematic diagram of a top view of a BJT semiconductor device provided in an embodiment of the present application. Figure 3 Shows Figure 2 Schematic diagram of the longitudinal section structure along AA direction.
[0036] Combination Figure 2 and Figure 3 It can be seen that the BJT semiconductor device includes a semiconductor substrate 200 , and the semiconductor substrate 200 includes a base region 210 , an emitter region 220 and a collector region 230 .
[0037] The upper surface of the base region 210 is exposed, and a polysilicon field effect structure 240 is formed on the upper surface of the base region 210. In this embodiment, the polysilicon field effect structure 240 is a closed ring. In this embodiment, the polysilicon field effect structure 240 includes a gate oxide layer directly in contact with the upper surface of the base region 210, and a polysilicon layer disposed on the gate oxide layer.
[0038] The emitter region 220 is formed in the base region 210 around the polysilicon field effect structure 240. In this embodiment, the emitter region 220 extends downward from the upper surface of the base region 210. In this embodiment, the side surface of the emitter region 220 contacts the base region 210 portion located below the polysilicon field effect structure 240.
[0039] The collector region 230 surrounds the base region 210 . In this embodiment, the collector region 230 is in contact with the bottom surface and the side surface of the base region 210 .
[0040] The polysilicon field effect structure 240 is electrically connected to the emitter region 220 .
[0041] In this embodiment, by electrically connecting the polysilicon field effect structure and the emitter region, a potential difference is formed in the base region below the polysilicon field effect structure. The potential difference can attract majority impurities in other base region parts, reduce the parasitic resistance in the base region, and improve the current amplification factor of the BJT semiconductor device.
[0042] Continue to refer to Figure 2 and Figure 3 In this embodiment, the polysilicon field effect structure 240 is a closed ring, so that the base region 210 portion located below the closed ring-shaped polysilicon field effect structure 240 forms a base region ring portion 211, and the base region ring portion 211 is a closed ring.
[0043] The base ring portion 211 divides the emitter region 220 into a first emitter region portion 221 and a second emitter region portion 222 .
[0044] The first emitter region portion 221 is in a closed ring shape, surrounding the base region ring portion 211 and contacting the outer side surface of the base region ring portion 211 .
[0045] The base ring portion 211 surrounds the second emitter portion 222 . The second emitter portion 222 contacts the inner side surface of the base ring portion 211 . The base ring portion 211 is connected to other portions of the base 210 as a whole.
[0046] In other embodiments, the polysilicon field effect structure 240 may also be in a spiral shape or a concentric circle shape, that is, the polysilicon field effect structure 240 may include a plurality of polysilicon field effect rings, and two adjacent polysilicon field effect rings are spaced apart.
[0047] The shape of the base region portion located below the polysilicon field effect structure 240 is consistent with the shape of the polysilicon field effect structure 240. Alternatively, the polysilicon field effect structure 240 includes a plurality of polysilicon field effect structure strips 241.
[0048] In addition, the polysilicon field effect structure may further include a plurality of polysilicon field effect structure strips, and the plurality of polysilicon field effect structure strips are arranged in parallel or crosswise on the base region.
[0049] Figure 4 A schematic diagram of the top view of the structure of a BJT semiconductor device provided in another embodiment of the present application is shown.
[0050] The polysilicon field effect structure 240 in this embodiment includes two polysilicon field effect structure strips 241 . The two polysilicon field effect structure strips 241 cross each other, so that the polysilicon field effect structure 240 forms a cross shape.
[0051] The base region portion located below the cross-shaped polysilicon field effect structure 240 also forms a cross shape, and the shape of the base region portion is consistent with the shape of the polysilicon field effect structure 240 .
[0052] The emitter region 220 is surrounded by the base region 210 at the periphery of the polysilicon field effect structure 240 and is formed by ion implantation.
[0053] The emitter region 220 contacts the side surface of the base region portion located below the polysilicon field effect structure 240 .
[0054] A distance is formed between the end of each polysilicon field effect structure strip 241 in the polysilicon field effect structure 240 and the outer edge of the emitter region 220 .
[0055] Figure 5 FIG. 1 shows a schematic diagram of a top view of a BJT semiconductor device provided in another embodiment of the present application. Figure 5 It can be seen from the figure that it includes a plurality of polysilicon field effect structure strips 241, and the plurality of polysilicon field effect structure strips 241 are cross-arranged to form a tic-tac-toe shape.
[0056] A distance is formed between the end of each polysilicon field effect structure strip 241 in the polysilicon field effect structure 240 and the outer edge of the emitter region 220 .
[0057] for Figures 1 to 5 In any of the figures, the base region portion located below the polysilicon field effect structure 240 is connected to other base region portions. The conductivity type of the majority impurities in the emitter region 220 is the same as the conductivity type of the majority impurities in the collector region 230, and can be both N-type or both P-type. The conductivity type of the majority impurities in the base region 210 is opposite to the conductivity type of the majority impurities in the emitter region 220, and the conductivity type of the majority impurities in the base region 210 is opposite to the conductivity type of the majority impurities in the collector region 230. When the conductivity type of the majority impurities in the emitter region 220 and the conductivity type of the majority impurities in the collector region 230 are both N-type, the conductivity type of the majority impurities in the base region 210 is P-type; when the conductivity type of the majority impurities in the emitter region 220 and the conductivity type of the majority impurities in the collector region 230 are both P-type, the conductivity type of the majority impurities in the base region 210 is N-type.
[0058] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection created by this application.
Claims
1. A BJT semiconductor device, It is characterized in that The BJT semiconductor device comprises a semiconductor substrate, wherein the semiconductor substrate comprises: A base region, on which a polysilicon field effect structure is formed; An emitter region formed in a base region around the polysilicon field effect structure; A collector region, the collector region surrounding the base region; Wherein, the polysilicon field effect structure is electrically connected to the emitter region; The polysilicon field effect structure is a closed ring, and the base region portion located below the closed ring-shaped polysilicon field effect structure forms a base region ring portion; The base region ring portion divides the emitter region into a first emitter region portion and a second emitter region portion; The first emitter region is in a closed ring shape, surrounding the base region ring portion; The base region ring portion surrounds the second emitter region portion.
2. The BJT semiconductor device according to claim 1, It is characterized in that The polysilicon field effect structure and the emitter region are electrically connected, so that a potential difference is formed in the base region below the polysilicon field effect structure. The potential difference can attract majority impurities in the base region and reduce the parasitic resistance in the base region.
3. The BJT semiconductor device according to claim 1, It is characterized in that A side surface of the emitter region contacts a portion of the base region below the polysilicon field effect structure.
4. The BJT semiconductor device according to claim 1, It is characterized in that The polysilicon field effect structure is in a strip shape; the base region portion located below the strip-shaped polysilicon field effect structure forms a base region strip portion; The base strip portion divides the emitter region into a first emitter region portion and a second emitter region portion located at two sides of the base strip portion.
5. The BJT semiconductor device according to claim 1, It is characterized in that The polysilicon field effect structure is any one of a spiral shape, a cross shape, and a field shape, and the shape of the base region portion located below the polysilicon field effect structure is consistent with the shape of the polysilicon field effect structure.
6. The BJT semiconductor device according to claim 1, It is characterized in that The polysilicon field effect structure comprises a plurality of polysilicon field effect structure strips; A plurality of polysilicon field effect structure strips are arranged in parallel or crosswise on the base region.
7. The BJT semiconductor device according to any one of claims 1 to 6, It is characterized in that The base region portion located below the polysilicon field effect structure is connected to other base region portions.
8. The BJT semiconductor device according to claim 1, It is characterized in that The conductivity type of the majority impurities in the emitter region is the same as the conductivity type of the majority impurities in the collector region; The conductivity type of the majority impurities in the base region is opposite to the conductivity type of the majority impurities in the emitter region, and the conductivity type of the majority impurities in the base region is opposite to the conductivity type of the majority impurities in the collector region.