Darlington device, preparation method thereof and electronic device

Abstract

The invention relates to a Darlington device and a preparation method thereof, and an electronic device. The Darlington device comprises a substrate of a first conduction type; the first doped region of the second conduction type is positioned on one side of the substrate; the first conductive type is opposite to the second conductive type; the second doped region of the second conduction type is located in the part, far away from the first doped region, of the substrate; the third doped region of the first conduction type is located in the second doped region, and the third doped region and the substrate are arranged at an interval; wherein the first doped region, the substrate and the second doped region form a first triode, and the substrate, the second doped region and the third doped region form a second triode. The Darlington device provided by the invention has higher current density.

Description

Technical Field

[0001] The present application relates to the technical field of integrated circuits, and in particular to a Darlington device and a preparation method thereof, and an electronic device. Background Art

[0002] A Darlington transistor is a composite structure consisting of two or more transistors, which can provide a much higher current gain than a single transistor. Currently, two transistors are usually prepared and the electrodes of the two transistors are interconnected to form a Darlington device. However, this structure obtains a larger current by sacrificing the device area, which does not meet the current demand for device miniaturization. Summary of the invention

[0003] Based on this, it is necessary to provide a Darlington device with high current density and small device size, a preparation method thereof, and an electronic device.

[0004] In order to achieve the above objectives, on the one hand, the present application provides a Darlington device, comprising:

[0005] a substrate of a first conductivity type;

[0006] A first doped region of a second conductivity type, located at one side of the substrate; the first conductivity type is opposite to the second conductivity type;

[0007] A second doping region of a second conductivity type is located in a portion of the substrate away from the first doping region;

[0008] A third doping region of the first conductivity type is located in the second doping region and is spaced apart from the substrate;

[0009] The first doping region, the substrate and the second doping region constitute a first triode, and the substrate, the second doping region and the third doping region constitute a second triode.

[0010] In one embodiment, the first doping region and the third doping region have different doping concentrations.

[0011] In one embodiment, the doping concentration of the first doping region is the same as that of the third doping region.

[0012] In one embodiment, the doping concentration of the third doping region is higher than the doping concentration of the second doping region.

[0013] In one embodiment, an extension length of the second doped region in a direction parallel to the substrate is smaller than an extension length of the substrate.

[0014] In one embodiment, it also includes:

[0015] The first electrode is located at a side of the first doping region away from the substrate.

[0016] In one embodiment, it also includes:

[0017] a second electrode, located at a side of the second doping region away from the substrate;

[0018] The third electrode is located at a side of the third doping region away from the substrate.

[0019] In one embodiment, it also includes:

[0020] an insulating layer, located on a side of the substrate away from the first doping region;

[0021] The second electrode and the third electrode penetrate the insulating layer along a direction perpendicular to the substrate.

[0022] In a second aspect, the present application also provides a method for preparing a Darlington device, comprising:

[0023] providing a substrate of a first conductivity type;

[0024] Doping one side of the substrate with a second conductivity type to form a second doped region, wherein the second conductivity type is opposite to the first conductivity type;

[0025] performing doping of the first conductivity type on the second doped region to form a third doped region;

[0026] Performing doping of a second conductivity type on a side of the substrate away from the second doping region to form a first doping region;

[0027] The first doping region, the substrate and the second doping region constitute a first triode, and the substrate, the second doping region and the third doping region constitute a second triode.

[0028] In a third aspect, the present application further provides an electronic device, comprising the Darlington device provided by any of the above embodiments.

[0029] In the above-mentioned Darlington device, its preparation method, and electronic device, the Darlington device includes a substrate of a first conductivity type, a first doping region of a second conductivity type, a second doping region of a second conductivity type, and a third doping region of a first conductivity type. Among them, the first doping region is located on one side of the substrate, the second doping region is located in a part of the substrate away from the first doping region, and the third doping region is located in the second doping region and is spaced from the substrate. The first doping region, the substrate, and the second doping region constitute a first triode, and the substrate, the second doping region, and the third doping region constitute a second triode. In the present application, the second doping region and the third doping region are formed on one side of the substrate as the base and the emitter, and the first doping region is formed on the other side of the substrate as the collector. The first doping region, the substrate, and the second doping region can be equivalent to the first triode, and the substrate, the second doping region, and the third doping region can be equivalent to the second triode, wherein the substrate can be used as the base of the first triode and the collector of the second triode, realizing the natural connection between the collector of the second triode and the base of the first triode, thereby realizing the Darlington device. Compared with the traditional method of forming two transistors on the same side of the substrate, the present application can significantly reduce the area of ​​the device with the same current gain, that is, the Darlington device of the present application has a higher current density. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 is one of the schematic cross-sectional structure diagrams of a Darlington device provided in an embodiment;

[0032] Figure 2 The second schematic diagram of the cross-sectional structure of a Darlington device provided in an embodiment;

[0033] Figure 3 is an equivalent circuit diagram of a Darlington device provided in an embodiment;

[0034] Figure 4 is an equivalent circuit diagram of a Darlington device provided in another embodiment;

[0035] Figure 5 The third schematic diagram of the cross-sectional structure of a Darlington device provided in an embodiment;

[0036] Figure 6 FIG4 is a fourth schematic diagram of a cross-sectional structure of a Darlington device provided in an embodiment;

[0037] Figure 7 A schematic flow chart of a method for preparing a Darlington device provided in an embodiment;

[0038] Figure 8 A schematic flow chart of a method for preparing a Darlington device provided in another embodiment;

[0039] Fig. 9 This is the output characteristic curve of the traditional Darlington device;

[0040] Fig.10 This is the output characteristic curve of the Darlington device provided in this application.

[0041] Description of reference numerals:

[0042] 100 - substrate, 200 - first doping region, 300 - second doping region, 400 - third doping region, 500 - first electrode, 600 - second electrode, 700 - third electrode, 800 - insulating layer. DETAILED DESCRIPTION

[0043] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0045] It should be understood that although the terms first, second, third, etc. may be used to describe various regions, conductivity types, and / or portions, these regions, conductivity types, and / or portions should not be limited by these terms. These terms are only used to distinguish one region, conductivity type, or portion from another region, conductivity type, or portion. Therefore, without departing from the teachings of the present invention, the first region, conductivity type, or portion discussed below may be represented as the second region, conductivity type, or portion; for example, the first doped region may be referred to as the second doped region, and the second doped region may be referred to as the first doped region, and both the first doped region and the second doped region may represent doped regions, but they do not represent the same doped region.

[0046] Spatially relative terms such as "under," "beneath," "below," "under," "above," "above," and the like may be used herein to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that, in addition to the orientations shown in the figures, spatially relative terms also include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, an element or feature described as "under other elements" or "under it" or "under it" will be oriented as being "above" the other elements or features. Thus, the exemplary terms "under" and "under" may include both upper and lower orientations. In addition, the device may also include additional orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptors used herein are interpreted accordingly.

[0047] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, in this specification, the term "and / or" includes any and all combinations of the relevant listed items.

[0048] Embodiments of the invention are described herein with reference to cross-sectional views which are schematic diagrams of ideal embodiments (and intermediate structures) of the invention, such that variations in the shapes shown due to, for example, manufacturing techniques and / or tolerances are anticipated. Thus, embodiments of the invention should not be limited to the specific shapes of the regions shown herein, but rather include deviations in shapes due to, for example, manufacturing techniques. For example, an implanted region shown as a rectangle typically has rounded or curved features and / or an implant concentration gradient at its edges rather than a binary change from an implanted region to a non-implanted region. Similarly, a buried region formed by implantation may result in some implantation in the region between the buried region and the surface through which the implantation is performed. Thus, the regions shown in the figures are schematic in nature, their shapes do not represent the actual shape of the region of the device, and do not limit the scope of the invention.

[0049] In one embodiment, Figure 1 or Figure 2As shown, the Darlington device provided in the present application includes a substrate 100, a first doping region 200, a second doping region 300 and a third doping region 400. Among them, the substrate 100 and the third doping region 400 have the same conductivity type, which is the first conductivity type, and the first doping region 200 and the second doping region 300 have the same conductivity type, which is the second conductivity type. The first conductivity type is opposite to the second conductivity type. Exemplarily, the first conductivity type is P-type and the second conductivity type is N-type; the first conductivity type is N-type and the second conductivity type is P-type.

[0050] The material of the substrate 100 can be any suitable substrate material doped with the first conductivity type known in the art, for example, it can be at least one of the following materials: silicon (Si), germanium (Ge), red phosphorus, silicon germanium (SiGe), silicon carbide (SiC), carbon germanium silicon (SiGeC), indium arsenide (InAs), gallium arsenide (GaAs), indium phosphide (InP) or other III / V compound semiconductors, including multilayer structures composed of these semiconductors.

[0051] The first doping region 200 is located on one side of the substrate 100, the second doping region 300 is located in a portion of the substrate 100 away from the first doping region 200, and the third doping region 400 is located in the second doping region 300 and is spaced apart from the substrate 100. The second doping region and the third doping region 400 are flush with the top surface of the substrate 100.

[0052] The first doping region 200, the substrate 100 and the second doping region 300 constitute a first triode. The substrate 100, the second doping region 300 and the third doping region 400 constitute a second triode. The first triode and the second triode constitute a Darlington device.

[0053] The circuit equivalent structure of the Darlington device of the present application is as follows Figure 3 or Figure 4As shown, the first doping region 200 can be used as the collector of the first triode, the substrate 100 can be used as the base of the first triode, and the second doping region 300 can be used as the emitter of the first triode; the substrate 100 can also be used as the collector of the second triode, the second doping region 300 can also be used as the base of the second triode, and the third doping region 400 can be used as the emitter of the second triode. Among them, the substrate 100 simultaneously serves as the collector of the second triode and the base of the first triode, realizing the natural connection between the collector of the second triode and the base of the first triode. The first doping region 200 can be used as the collector of the Darlington device as a whole, the second doping region 300 can be used as the base of the Darlington device as a whole, and the third doping region 400 can be used as the emitter of the Darlington device as a whole. Its working principle is: a positive voltage (greater than the conduction voltage) is applied to the base. When a small current flows through the base, the emitter will emit a large number of electrons, and these electrons are collected by the collector after passing through the base to form a collector current.

[0054] The polarity of the first triode and the second triode is different. When the first conductivity type is P type and the second conductivity type is N type, the first doping region 200, the substrate 100 and the second doping region 300 constitute an NPN triode, and the substrate 100, the second doping region 300 and the third doping region 400 constitute a PNP triode; when the first conductivity type is N type and the second conductivity type is P type, the first doping region 200, the substrate 100 and the second doping region 300 constitute a PNP triode, and the substrate 100, the second doping region 300 and the third doping region 400 constitute an NPN triode.

[0055] In the embodiment of the present application, the Darlington device includes a substrate 100 of a first conductivity type, a first doping region 200 of a second conductivity type, a second doping region 300 of a second conductivity type, and a third doping region 400 of a first conductivity type. The first doping region 200 is located on one side of the substrate 100, the second doping region 300 is located in a portion of the substrate 100 away from the first doping region 200, and the third doping region 400 is located in the second doping region 300 and is spaced from the substrate 100. The first doping region 200, the substrate 100, and the second doping region 300 constitute a first triode, and the substrate 100, the second doping region 300, and the third doping region 400 constitute a second triode. The present application forms a second doping region 300 and a third doping region 400 as a base and an emitter on one side of the substrate 100, and forms a first doping region 200 as a collector on the other side of the substrate 100. The first doping region 200, the substrate 100, and the second doping region 300 can be equivalent to a first triode, and the substrate 100, the second doping region 300, and the third doping region 400 can be equivalent to a second triode, wherein the substrate 100 can be used as the base of the first triode and the collector of the second triode, thereby realizing the natural connection between the collector of the second triode and the base of the first triode, thereby realizing the function of the Darlington device. Compared with the traditional method of forming two transistors on the same side of the substrate 100, the present application can reduce the area of ​​the device under the condition of having the same current gain, that is, the Darlington device of the present application has a higher current density.

[0056] In one embodiment, the first doping region 200 and the third doping region 400 have different doping concentrations.

[0057] Optionally, in one embodiment, the doping concentrations of the first doping region 200 and the third doping region 400 may also be the same.

[0058] The doping concentration, doping material, etc. of the first doping region 200 and the third doping region 400 can be reasonably set according to the actual business scenario requirements, and the embodiments of the present application are not limited here.

[0059] In one embodiment, the doping concentration of the third doping region 400 is higher than the doping concentration of the second doping region 300. The third doping region 400 is located in the second doping region 300, and the doping concentration of the third doping region 400 must be higher than the doping concentration of the second doping region 300 so that the conductivity type of the third doping region 400 is opposite to the conductivity type of the second doping region 300.

[0060] In one embodiment, the extension length of the second doping region 300 in the direction parallel to the substrate 100 is smaller than the extension length of the substrate 100. The direction parallel to the substrate 100 is the horizontal direction in the figure.

[0061] In one embodiment, Figure 5or Figure 6 As shown, the Darlington device further includes a first electrode 500. The first electrode 500 is located on a side of the first doping region 200 away from the substrate 100. The material of the first electrode 500 includes, but is not limited to, metals such as aluminum, copper, titanium, and tungsten.

[0062] In one embodiment, Figure 5 or Figure 6 As shown, the Darlington device further includes a second electrode 600 and a third electrode 700, wherein the second electrode 600 is located on a side of the second doping region 300 away from the substrate 100, and the third electrode 700 is located on a side of the third doping region 400 away from the substrate 100. The material of the second electrode 600 includes but is not limited to one or more of aluminum, copper, titanium, tungsten, etc., and the material of the third electrode 700 includes but is not limited to one or more of aluminum, copper, titanium, tungsten, etc. The second electrode 600 is used to lead the second doping region 300 out to connect to an external circuit, and the third electrode 700 is used to lead the third doping region 400 out to connect to an external circuit.

[0063] In one embodiment, Figure 5 or Figure 6 As shown, the Darlington device further includes an insulating layer 800. The insulating layer 800 is located on a side of the substrate 100 away from the first doping region 200. The second electrode 600 and the third electrode 700 penetrate the insulating layer 800 in a direction perpendicular to the substrate 100. The material of the insulating layer 800 includes but is not limited to one or more of oxides, carbon oxides, nitrogen oxides, and carbon nitride oxides. The insulating layer 800 can be used to isolate the second doping region 300 and the third doping region 400 from other structures.

[0064] In one embodiment, the present application also provides a method for preparing a Darlington device, such as Figure 7 As shown, it includes steps 702 to 708.

[0065] Step 702: provide a substrate of a first conductivity type.

[0066] The material of the substrate 100 can be any suitable substrate material doped with the first conductivity type known in the art, for example, it can be at least one of the following materials: silicon (Si), germanium (Ge), red phosphorus, silicon germanium (SiGe), silicon carbide (SiC), carbon germanium silicon (SiGeC), indium arsenide (InAs), gallium arsenide (GaAs), indium phosphide (InP) or other III / V compound semiconductors, including multilayer structures composed of these semiconductors.

[0067] Step 704 , doping one side of the substrate with a second conductivity type to form a second doped region.

[0068] The second conductivity type is opposite to the first conductivity type.

[0069] like Figure 1 or Figure 2 As shown, the second conductivity type can be doped on one side of the substrate 100 by a diffusion process or an ion implantation process to form a second doping region 300. Taking the first conductivity type as N type and the second conductivity type as P type as an example, the substrate 100 can be doped with trivalent elements such as aluminum or boron by a diffusion process or an ion implantation process to form a P-type second doping region 300.

[0070] Step 706 , doping the second doped region with the first conductivity type to form a third doped region.

[0071] like Figure 1 or Figure 2 As shown, the first conductivity type can be doped into the second doping region 300 by a diffusion process or an ion implantation process to form a third doping region 400. Taking the first conductivity type as N type and the second conductivity type as P type as an example, the second doping region 300 can be doped with a pentavalent element such as nitrogen, phosphorus, arsenic or antimony by a diffusion process or an ion implantation process to form an N type third doping region 400.

[0072] Step 708 , doping the second conductivity type is performed on a side of the substrate away from the second doping region to form a first doping region.

[0073] like Figure 1 or Figure 2 As shown, the obtained structure can be turned over, and the second conductivity type is doped on the side of the substrate 100 away from the second doping region 300 through a diffusion process or an ion implantation process to form the first doping region 200 .

[0074] The first doping region 200 , the substrate 100 , and the second doping region 300 constitute a first triode, and the substrate 100 , the second doping region 300 , and the third doping region 400 constitute a second triode.

[0075] In this embodiment, by providing a substrate 100 of the first conductivity type, doping the second conductivity type on one side of the substrate 100 to form a second doping region 300, doping the first conductivity type on the second doping region 300 to form a third doping region 400, doping the second conductivity type on the side of the substrate 100 away from the second doping region 300 to form a first doping region 200, the first doping region 200, the substrate 100 and the second doping region 300 constitute a first triode, the substrate 100, the second doping region 300 and the third doping region 400 constitute a second triode, and the function of the Darlington device is realized. Compared with the traditional method of forming two transistors on the same side of the substrate 100, under the condition of achieving the same current gain, the present application can reduce the area of ​​the device, that is, the Darlington device of the present application has a higher current density.

[0076] In one embodiment, after forming the first doping region, the method for preparing the Darlington device further includes the step of forming a first electrode on a side of the first doping region away from the substrate. Specifically, a metal material can be deposited on a side of the first doping region 200 away from the substrate 100 by a deposition process to form the first electrode 500.

[0077] In one embodiment, after forming the third doping region, as Figure 8 As shown, the method for preparing the Darlington device further includes steps 802 to 806.

[0078] Step 802 , forming an insulating layer on a side of the substrate away from the first doped region.

[0079] like Figure 5 or Figure 6 As shown, an insulating material may be deposited on a side of the substrate 100 away from the first doping region 200 by a deposition process to form an insulating layer 800 .

[0080] Step 804 , forming a first opening and a second opening in the insulating layer.

[0081] Photolithography and etching processes may be used to form a first opening and a second opening in the insulating layer 800. The first opening exposes a portion of the surface of the second doping region 300, and the second opening exposes a portion of the surface of the third doping region 400.

[0082] Step 806 , forming a first electrode in the first opening, and forming a second electrode in the second opening.

[0083] like Figure 5 or Figure 6As shown, specifically, a deposition process can be used to deposit a metal material layer on the first opening, the second opening and the surface of the insulating layer 800, and the metal material layer is polished to expose the insulating layer 800. The remaining metal material layer in the first opening can be used as the second electrode 600, and the remaining metal material layer in the second opening can be used as the third electrode 700.

[0084] In one embodiment, the present application further provides an electronic device, which may include the Darlington device provided by any of the above embodiments.

[0085] In order to better illustrate the effect of the Darlington device provided in the present application on improving the current density, under the same cell area, the output characteristic curves of the traditional Darlington device and the Darlington device of the present application were tested respectively. Fig. 9 is the output characteristic curve of the traditional Darlington device, Fig.10 The output characteristic curve of the Darlington device of the present application, wherein the horizontal axis represents the collector voltage Vc, and the vertical axis represents the collector current Ic. Fig. 9 and Fig.10 It can be clearly seen that the output current of the Darlington device of the present application is larger than the output current of the traditional Darlington device.

[0086] It should be understood that, although the steps in the above flowchart are displayed in the order shown in the figure, these steps are not necessarily executed in this order. Unless otherwise specified in this document, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least part of the steps in the figure may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be executed in turn or alternating with other steps or at least part of the steps or stages in other steps. For example, it can be executed in accordance with Figure 7 In the order shown, step 702 is performed first, and then step 704 and step 706 are performed; step 704 and step 706 may also be performed first, and then step 702 is performed.

[0087] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", "ideal embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0088] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features of the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0089] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A Darlington device, characterized in that: include: a substrate of a first conductivity type; A first doped region of a second conductivity type, located on one side of the substrate; The first conductivity type is opposite to the second conductivity type; A second doping region of a second conductivity type is located in a portion of the substrate away from the first doping region; A third doping region of the first conductivity type is located in the second doping region and is spaced apart from the substrate; The first doping region, the substrate and the second doping region constitute a first triode, and the substrate, the second doping region and the third doping region constitute a second triode.

2. The Darlington device according to claim 1, characterized in that: The first doping region and the third doping region have different doping concentrations.

3. The Darlington device according to claim 1, characterized in that: The first doping region and the third doping region have the same doping concentration.

4. The Darlington device according to claim 1, characterized in that: The doping concentration of the third doping region is higher than the doping concentration of the second doping region.

5. The Darlington device according to claim 1, characterized in that: An extension length of the second doping region in a direction parallel to the substrate is smaller than an extension length of the substrate.

6. The Darlington device according to claim 1, characterized in that: Also includes: The first electrode is located at a side of the first doping region away from the substrate.

7. The Darlington device according to claim 1, characterized in that: Also includes: a second electrode, located at a side of the second doping region away from the substrate; The third electrode is located at a side of the third doping region away from the substrate.

8. The Darlington device according to claim 7, characterized in that: Also includes: an insulating layer, located on a side of the substrate away from the first doping region; The second electrode and the third electrode penetrate the insulating layer along a direction perpendicular to the substrate.

9. A method for preparing a Darlington device, characterized in that: include: providing a substrate of a first conductivity type; Doping one side of the substrate with a second conductivity type to form a second doped region, wherein the second conductivity type is opposite to the first conductivity type; performing doping of the first conductivity type on the second doped region to form a third doped region; Performing doping of a second conductivity type on a side of the substrate away from the second doping region to form a first doping region; The first doping region, the substrate and the second doping region constitute a first triode, and the substrate, the second doping region and the third doping region constitute a second triode.

10. An electronic device, characterized in that: Comprising a Darlington device as described in any one of claims 1-8.

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