A voltage controlled conduction method for a triode

Abstract

The present invention discloses a voltage-controlled conduction method for a triode, comprising the following steps: when a forward voltage VGC is applied between a gate and a collector, an electric field is formed between the oxide layer of the gate and the collector, the electric field attracts free electrons in a control region to gather, and repels holes in the control region; the voltage VGC gradually increases, and when the voltage VGC reaches a conduction voltage VT, a first type of conductive channel is formed in a collector region; after the first type of conductive channel is formed in the collector region, if a driving voltage VCE exists between an emitter and a collector, VCE>VGC; free electrons in the first type of conductive channel in the collector region move toward the emitter, thereby forming a current ICE, and realizing conduction of the triode. The present invention uses voltage-controlled conduction, does not require current control, retains the voltage-controlled conduction characteristics of a MOS tube, and thus has low control power consumption and high switching frequency; at the same time, retains the current conduction characteristics of the triode, has low conduction power consumption, and has a simple structure and low cost compared to an IGBT.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor devices, and in particular to a voltage-controlled conduction method for a triode. Background Art

[0002] Transistors, MOS tubes and IGBTs are common semiconductor devices. These devices each have unique advantages and disadvantages in controlling power consumption, conduction power consumption, switching frequency and cost, and are suitable for different application scenarios.

[0003] The existing triode is turned on by current control, which has the problems of high control power consumption and low switching frequency, but the cost is relatively low and suitable for mass production. MOS tube has high power consumption and high cost. IGBT is a new device formed by combining triode and MOS tube, which avoids the disadvantages of high control power consumption and high conduction power consumption, but still has the problems of low switching frequency, complex implementation structure and high cost. Summary of the invention

[0004] The purpose of the present invention is to provide a voltage-controlled conduction method for a triode, which utilizes voltage-controlled conduction without current control, retains the voltage-controlled conduction characteristics of a MOS tube, and thus has low control power consumption and high switching frequency; at the same time, it retains the current conduction characteristics of the triode, has low conduction power consumption, and has a simple structure and low cost compared to an IGBT; and has no substrate, and will not generate a large depletion layer with the emitter, so that the on-resistance will not increase.

[0005] In order to achieve the above purpose, the following technical solutions are adopted:

[0006] A voltage-controlled conduction method for a triode comprises the following steps:

[0007] Step S1: When a forward voltage VGC is applied between the gate and the collector, an electric field is formed between the oxide layers of the gate and the collector, and the electric field attracts free electrons in the control region to gather and repels holes in the control region;

[0008] Step S2: the voltage VGC gradually increases, and when the voltage VGC reaches the turn-on voltage VT, a first type conductive channel is formed in the collector region;

[0009] Step S3: After the first type conductive channel is formed in the collector region, if there is a driving voltage VCE between the emitter and the collector, since the emitter potential is higher than the gate potential, VCE>VGC;

[0010] Step S4: the free electrons in the first type conductive channel of the collector region move toward the emitter, and the free electrons in the collector and the gate are adsorbed to the emitter, thereby forming a current ICE, and realizing the conduction of the transistor.

[0011] Preferably, the control region is provided with an insulating mesh gate plate, and the insulating mesh gate plate is arranged close to the emitter.

[0012] Preferably, the position of the insulating mesh gate plate can be adjusted according to the concentration of the PN junction and the voltage VGE.

[0013] Preferably, the insulating mesh grid plate is a conductive material wrapped by an insulating layer.

[0014] By adopting the above scheme, the beneficial effects of the present invention are:

[0015] 1) It uses voltage to control conduction without current control, retaining the voltage-controlled conduction characteristics of the MOS tube, so the control power consumption is small and the switching frequency is high;

[0016] 2) It retains the current conduction characteristics of the transistor, has low conduction power consumption, and has a simpler structure and lower cost than IGBT;

[0017] 3) Without a substrate, there will not be a large depletion layer between the emitter and the transistor, so the on-resistance will not increase. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention;

[0019] Figure 2 This is a schematic diagram of the NPN transistor structure when no voltage is applied to the present invention;

[0020] Figure 3 The external voltage V GC The schematic diagram of the NPN transistor principle after that;

[0021] Figure 4 For the present invention, there is a voltage V CE The schematic diagram of the NPN transistor principle after that;

[0022] Figure 5 It is a schematic diagram of the cross-sectional structure of the insulating mesh grid plate of the present invention;

[0023] The accompanying drawings illustrate:

[0024] 1—Triode, 2—Free electrons,

[0025] 3—insulating mesh grid plate, 31—mesh hole. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0027] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0028] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0029] Reference Figures 1 to 5 As shown, the present invention provides a voltage-controlled conduction method for a transistor, comprising the following steps: Step S1: When a forward voltage VGC is applied between the gate and the collector, an electric field is formed between the oxide layers of the gate and the collector, and the electric field attracts free electrons 2 in the control area to gather and repels holes in the control area; Step S2: The voltage VGC gradually increases, and when the voltage VGC reaches the turn-on voltage VT, a first type of conductive channel is formed in the collector area; Step S3: After the first type of conductive channel is formed in the collector area, if there is a driving voltage VCE between the emitter and the collector, since the emitter potential is higher than the gate potential, VCE>VGC; Step S4: The free electrons 2 in the first type of conductive channel in the collector area move toward the emitter, and the free electrons 2 in the collector and the gate are adsorbed to the emitter, thereby forming a current ICE, and the transistor 1 is turned on.

[0030] Voltage V GC Refers to the voltage between the gate (G pole) and the collector (C pole), voltage V CE Refers to the voltage between the collector (C pole) and the emitter (E pole), voltage V GE It refers to the voltage between the gate (G pole) and the emitter (E pole), and the current I CE Refers to the current between the collector (C pole) and the emitter (E pole).

[0031] Please continue to refer to Figure 1-4 , build a peripheral circuit for the new transistor 1, where Figure 2This is a schematic diagram of the NPN transistor structure when no voltage is applied. Figure 3 is the external voltage V GC The schematic diagram of the NPN transistor principle is shown below. Figure 4 There is a voltage V CE The schematic diagram of the NPN transistor principle is shown below.

[0032] The insulated mesh gate plate 3 is located in the control region and is biased towards the emitter. The specific position depends on the concentration and voltage V of each junction of the NPN transistor 1 (PNP transistor 1). GE Adjustment is made, and different positions reflect different characteristics of the on-state voltage.

[0033] The insulating mesh grid plate 3 is a conductive material wrapped in an insulating layer. The greater the design density, the stronger the voltage field, the lower the control voltage, but the smaller the density of electrons passing through; the smaller the density, the weaker the voltage field, the higher the control voltage, and the greater the density of electrons passing through. Please continue to refer to Figure 5 The interior of the insulating mesh grid plate 3 is a circular grid, but it is not limited to this. A square grid or other shapes may also be used. The specific parameters of the transistor 1 need to ensure that the electric field is applied and free electrons pass through.

[0034] The basic working principle of the present invention is to use the voltage V GC Control the formation current I CE , by establishing a conductive channel and current I CE To achieve voltage-controlled conduction, avoiding the high power consumption problem caused by current control.

[0035] Please continue to refer to Figure 1 , the control region, collector region and emitter region of the novel transistor 1. In the NPN transistor 1, the control region is the P region; in the PNP transistor 1, the control region is the N region. In a specific embodiment, the transistor 1 is an NPN transistor, and the first type of conductive channel is an N type conductive channel.

[0036] Please continue to refer to Figure 3 , there is no original conductive channel between the emitter and the collector, so it is necessary to establish an N-type conductive channel first when working: when a forward voltage is applied between the gate and the collector, that is, V GC >0, an electric field with positive on the left and negative on the right appears between the oxide layer of the gate and the collector. This electric field will attract free electrons 2 in the P region, causing them to gather on the right side of the oxide layer, and at the same time repel holes in the P region, causing them to leave the region. This voltage V GC It is the key voltage to control the conduction of transistor 1, which is used to control the conduction characteristics of the new transistor 1. GC The larger the electric field strength, the more obvious this effect is. GC Reaching the on-state voltage V TWhen the concentration of free electrons 2 gathered in this area is large enough, a new N-type area is formed, connecting the collector and the gate like a bridge. This area is called an N-type conductive channel, or N channel for short, and V T It is called the turn-on voltage, V GC ≥V T It is a necessary condition for establishing the N-type conductive channel.

[0037] Please continue to refer to Figure 4 , forming a current I CE :After the N-type conductive channel is established, if there is a certain driving voltage V between the emitter and the collector CE When the voltage V CE After it appears, since the emitter (E pole) potential is higher than the gate (G pole) potential, V CE >V GC , so the electric field distribution around the oxide layer is uneven, the intensity is large near the emitter, the free electrons 2 in the N-type conductive channel of the collector region move toward the emitter, and the corresponding conductive channel changes accordingly: the free electrons 2 in the collector region and the control region are adsorbed to the emitter region, thus forming a current I CE .

[0038] In another embodiment, the transistor 1 is a PNP transistor, and the first type of conductive channel is a P type conductive channel. The principle of the voltage controlled conduction method is similar and will not be described in detail here.

[0039] The beneficial effects of the present invention are:

[0040] 1) It uses voltage to control conduction without current control, retaining the voltage-controlled conduction characteristics of the MOS tube, so the control power consumption is small and the switching frequency is high;

[0041] 2) It retains the current conduction characteristics of the transistor, has low conduction power consumption, and has a simpler structure and lower cost than IGBT;

[0042] 3) Without a substrate, there will not be a large depletion layer between the emitter and the transistor, so the on-resistance will not increase.

[0043] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention. Obviously, the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A voltage-controlled conduction method for a triode, characterized in that: The following steps are involved: Step S1: When a forward voltage V is applied between the gate and the collector GC When the gate and collector oxide layers are connected, an electric field is formed between them. This electric field attracts free electrons in the control region and repels holes in the control region. Step S2: Voltage V GC Gradually increases, when the voltage V GC Reaching the on-state voltage V T When a first type of conductive channel is formed in the collector region; Step S3: After the first type of conductive channel is formed in the collector region, if there is a driving voltage V between the emitter and the collector CE , since the emitter potential is higher than the gate potential, V CE >V GC ; Step S4: The free electrons in the first type conductive channel of the collector region move toward the emitter, and the free electrons in the collector and the gate are attracted to the emitter, thereby forming a current I CE , to realize the conduction of the transistor.

2. The voltage-controlled conduction method of a transistor according to claim 1, characterized in that: The control area is provided with an insulating mesh grid plate, and the insulating mesh grid plate is arranged close to the emitter.

3. The voltage-controlled conduction method of a transistor according to claim 2, characterized in that: The insulating mesh gate plate can be based on the concentration of the PN junction and the voltage V GE Adjust the position.

4. The voltage-controlled conduction method of a transistor according to claim 2, characterized in that: The insulating mesh grid plate is a conductive material wrapped by an insulating layer.

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