CN110534565A - A kind of bipolar junction transistor - Google Patents
A kind of bipolar junction transistor Download PDFInfo
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- CN110534565A CN110534565A CN201910850313.9A CN201910850313A CN110534565A CN 110534565 A CN110534565 A CN 110534565A CN 201910850313 A CN201910850313 A CN 201910850313A CN 110534565 A CN110534565 A CN 110534565A
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- base area
- type base
- emitter region
- collecting zone
- emitter
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- 239000000463 material Substances 0.000 claims abstract description 15
- 238000000034 method Methods 0.000 claims abstract description 14
- 239000000758 substrate Substances 0.000 claims description 20
- 239000002210 silicon-based material Substances 0.000 claims description 4
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 abstract description 18
- 229910010271 silicon carbide Inorganic materials 0.000 abstract description 17
- 230000015556 catabolic process Effects 0.000 abstract description 11
- 238000002347 injection Methods 0.000 abstract description 8
- 239000007924 injection Substances 0.000 abstract description 8
- 229910052710 silicon Inorganic materials 0.000 abstract description 8
- 239000010703 silicon Substances 0.000 abstract description 8
- 230000004888 barrier function Effects 0.000 abstract description 5
- 230000015572 biosynthetic process Effects 0.000 abstract description 4
- 230000005684 electric field Effects 0.000 abstract description 4
- 239000003380 propellant Substances 0.000 abstract description 2
- 239000004065 semiconductor Substances 0.000 abstract description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 6
- 230000008901 benefit Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 238000002161 passivation Methods 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
- H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/26—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, elements provided for in two or more of the groups H01L29/16, H01L29/18, H01L29/20, H01L29/22, H01L29/24, e.g. alloys
- H01L29/267—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, elements provided for in two or more of the groups H01L29/16, H01L29/18, H01L29/20, H01L29/22, H01L29/24, e.g. alloys in different semiconductor regions, e.g. heterojunctions
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
- H01L29/70—Bipolar devices
- H01L29/72—Transistor-type devices, i.e. able to continuously respond to applied control signals
- H01L29/73—Bipolar junction transistors
- H01L29/732—Vertical transistors
- H01L29/7327—Inverse vertical transistors
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- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Ceramic Engineering (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Bipolar Transistors (AREA)
Abstract
The present invention relates to a kind of bipolar junction transistors, belong to high power semiconductor technical field.The present invention mainly passes through the bonding of silicon carbide and silicon, form two heterojunction interfaces, specially, p-type base area and N+ emitter region are using bonding techniques formation hetero-junctions, p-type base area and N- collecting zone are using bonding techniques formation hetero-junctions, the efficiency that heterogeneous propellant knot injects electronics is very high, this is because the inverse injection in hole is almost stopped by an additional hole barrier, it is minimum from the hole dissufion current value of base area injection emitter region, therefore the injection efficiency of emitter junction is high, greatly improves the current gain of device.Further, since collecting zone of the invention uses carbofrax material, on collector junction, the critical breakdown electric field of silicon carbide is 10 times of silicon, therefore greatly improves the breakdown voltage of device for most of voltage drop.
Description
Technical field
The invention belongs to high power semiconductor technical fields, and in particular to a kind of bipolar junction transistor.
Background technique
Research find bipolar junction transistor because have lower switching loss and faster switching speed become it is non-often with
Promising power device.In the application for requiring high power density and hot operation, such as hybrid-electric car
Traction drive system and power application equipment, SiC BJT are received extensive attention with its excellent performance.Silicon carbide (SiC) is double
Pole junction transistor (BJT) has lower switching loss and faster switching speed, is important one of normally closed device.Phase
To Si base triode, SiC BJT has many advantages, such as lower conducting voltage, and secondary-breakdown phenomenon is not present；SiC BJT is avoided
SiC is not present without the big disadvantage of SiC IGBT conduction loss in the gate driving problem of normally on device SiC JFET
MOSFET because gate medium poor reliability and channel mobility it is low and the problem of be restricted device operating conditions.
Although BJT there are many advantages, many problems are still suffered from.BJT is current control device, for efficient
For power switch, it is necessary to have very high current gain.Compared with other device for power switching, the current gain of SiC BJT
It need to be improved, current gain can be improved by better epitaxial growth conditions and the surface passivation technology of optimization.In height
Frequency application in need switching device have very little conductivity modulation effect, the important feature of SiC BJT performance be current gain,
Conducting resistance and breakdown voltage.Existing technology presently, there are the shortcomings that be that it can not provide sufficiently high common emitter electricity simultaneously
Flow enhancement and breakdown voltage.
Summary of the invention
The technical problem to be solved by the present invention is in view of the problems of the existing technology, provide a kind of bipolar junction transistor
Pipe.
In order to solve the above technical problems, the embodiment of the present invention provides a kind of bipolar junction transistor, including collector, first
N+ substrate, N- collecting zone, p-type base area, N+ emitter region, the 2nd N+ substrate, emitter, the first base stage and the second base stage；
The collector, the first N+ substrate, the N- collecting zone and the p-type base area stack gradually set from bottom to up
It sets, the N+ emitter region is located on the p-type base area, and the 2nd N+ substrate and the emitter are sequentially located at the N+ transmitting
Qu Shang, first base stage and second base stage are located at the two sides of the N+ emitter region, and are located at the p-type base area
On；
It is characterized in that, the first N+ substrate and the N- collecting zone are carbofrax material, the p-type base area is silicon material
Material, the N+ emitter region and the 2nd N+ substrate are carbofrax material, and the N- collecting zone and the p-type base area pass through bonding
Technology formation hetero-junctions, the p-type base area and the N+ emitter region form hetero-junctions by bonding techniques.
Based on the above technical solution, the present invention can also be improved as follows.
Further, the doping concentration of the p-type base area is 1 × 1016cm-3。
Further, the doping concentration of the N+ emitter region is 1.2 × 1019cm-3。
Further, the doping concentration of the N- collecting zone is 1.8 × 1015cm-3。
The beneficial effects of the present invention are: comparing traditional technology, the present invention does not need the electrode of additional applying bias voltage,
Still retainer member is three terminal device；Emitter region of the invention is the silicon carbide of broad stopband, and base area is the relatively narrow silicon materials of forbidden band, is adopted
The hetero-junctions of silicon carbide and silicon is formed with bonding techniques, so that transmitting be made to become hetero-junctions, the design of this hetero-junctions is great
The injection efficiency of device is improved, and the doping concentration of base area can be greatly improved, reduces base resistance.Collecting zone is
Carbofrax material, the critical breakdown electric field of silicon carbide are 10 times of silicon or so, and collecting zone bears pressure resistance, greatly improve breakdown
Voltage, to improve common emitter current gain and breakdown voltage simultaneously.
Detailed description of the invention
Fig. 1 is a kind of structural schematic diagram of bipolar junction transistor of the embodiment of the present invention；
Fig. 2 is the heterojunction structure output characteristics simulation curve figure of the embodiment of the present invention.
In attached drawing, parts list represented by the reference numerals are as follows:
1, emitter, the 2, the 2nd N+ substrate, 3, N+ emitter region, the 4, first base stage, the 5, second base stage, 6, N- collecting zone, 7,
First N+ substrate, 8, collector, 9, p-type base area.
Specific embodiment
The principle and features of the present invention will be described below with reference to the accompanying drawings, and the given examples are served only to explain the present invention, and
It is non-to be used to limit the scope of the invention.
As shown in Figure 1, a kind of bipolar junction transistor provided in an embodiment of the present invention, including collector 8, the first N+ substrate
7, N- collecting zone 6, p-type base area 9, N+ emitter region 3, the 2nd N+ substrate 2, emitter 1, the first base stage 4 and the second base stage 5；
The collector 8, the first N+ substrate 7, the N- collecting zone 6 and the p-type base area 9 successively layer from bottom to up
Folded setting, the N+ emitter region 3 are located on the p-type base area 9, and the 2nd N+ substrate 2 and the emitter 1 are sequentially located at institute
It states in N+ emitter region 3, first base stage 4 and second base stage 5 are located at the two sides of the N+ emitter region 3, and are located at
On the p-type base area 9；
It is characterized in that, the first N+ substrate 7 and the N- collecting zone 6 are carbofrax material, the p-type base area 9 is
Silicon materials, the N+ emitter region 3 and the 2nd N+ substrate 2 are carbofrax material, the N- collecting zone 6 and the p-type base area 9
Hetero-junctions is formed by bonding techniques, the p-type base area 9 and the N+ emitter region 3 form hetero-junctions by bonding techniques.
In above-described embodiment, for structure of the invention compared with traditional structure, the present invention mainly passes through the key of silicon carbide and silicon
Conjunction forms two heterojunction interfaces, and wherein p-type base area 9 and N+ emitter region 3 are using bonding techniques formation hetero-junctions, 9 He of p-type base area
N- collecting zone 6 forms hetero-junctions using bonding techniques, in addition, the present invention is using the biggish carbofrax material of forbidden bandwidth as transmitting
Area, the lesser silicon of forbidden bandwidth is as base area, and the efficiency of the injection electronics of heterogeneous propellant knot is very high, this is because hole is reversed
Injection is almost stopped by an additional hole barrier, i.e., the injection efficiency of emitter junction is mainly by the difference of knot both sides forbidden bandwidth
An additional hole barrier caused by different determines, minimum from the hole dissufion current value of base area injection emitter region, and with hair
The doping concentration for penetrating area and base area is substantially unrelated.Great benefit is thus brought, it can be dense using the doping for improving base area
It spends with the method for base width and reduces base resistance, reduce the barrier capacitance of collector, reduce the barrier capacitance etc. of emitter junction
Parasitic capacitance.To sum up, the emitter junction of hetero-junctions can greatly improve the current gain of device.
Since collector junction of the invention is also heterojunction interface, wherein p-type base area 9 and N- collecting zone 6 use bonding techniques shape
At hetero-junctions, when the open base of BJT, when current collection grade adds positive bias, emitter junction positively biased, collector junction is reverse-biased, most of voltage
Drop is on collector junction, and since the collecting zone that the present invention uses is the material of silicon carbide, the critical breakdown electric field of silicon carbide is silicon
10 times, therefore greatly improve the breakdown voltage of device.
Optionally, the doping concentration of the p-type base area 9 is 1 × 1016cm-3。
Optionally, the doping concentration of the N+ emitter region 3 is 1.2 × 1019cm-3。
Optionally, the doping concentration of the N- collecting zone 6 is 1.8 × 1015cm-3。
Illustrate the beneficial effect of structure of the invention below by emulation.In simulation process, setting base current be 1 ×
10-10A, Fig. 2 are the output characteristic curve of double-heterostructure of the invention, and solid line therein indicates the collector of double heterojunction
Electric current with collector voltage curve, dotted line indicate double heterojunction base current with collector voltage curve.
Figure it is seen that being 1 × 10 in base current-10When A, collector current is 2 × 10-8A can calculate double heterojunction knot
The current gain of structure is 200, and the current gain of Conventional silicon carbide bipolar junction transistor only has 10-20 or so.Therefore it uses
Double-heterostructure is 1 × 10 in base current-10Current gain when A improves 10 times, and the gain of electric current greatly improves.
And when open base, collector adds positive bias, and emitter junction positively biased, collector junction is reverse-biased, and most of pressure drop drop is in current collection
It ties, collector junction forms depletion region.Since the critical breakdown electric field of carbofrax material is much larger than silicon, breakdown of the invention
Voltage will also be far longer than traditional silica-base material.
In the description of the present invention, it is to be understood that, term " center ", " longitudinal direction ", " transverse direction ", " length ", " width ",
" thickness ", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom" "inner", "outside", " up time
The orientation or positional relationship of the instructions such as needle ", " counterclockwise ", " axial direction ", " radial direction ", " circumferential direction " be orientation based on the figure or
Positional relationship is merely for convenience of description of the present invention and simplification of the description, rather than the device or element of indication or suggestion meaning must
There must be specific orientation, be constructed and operated in a specific orientation, therefore be not considered as limiting the invention.
In addition, term " first ", " second " are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance
Or implicitly indicate the quantity of indicated technical characteristic.Define " first " as a result, the feature of " second " can be expressed or
Implicitly include at least one this feature.In the description of the present invention, the meaning of " plurality " is at least two, such as two, three
It is a etc., unless otherwise specifically defined.
In the present invention unless specifically defined or limited otherwise, term " installation ", " connected ", " connection ", " fixation " etc.
Term shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or integral；It can be mechanical connect
It connects, is also possible to be electrically connected；It can be directly connected, can also can be in two elements indirectly connected through an intermediary
The interaction relationship of the connection in portion or two elements, unless otherwise restricted clearly.For those of ordinary skill in the art
For, the specific meanings of the above terms in the present invention can be understood according to specific conditions.
In the present invention unless specifically defined or limited otherwise, fisrt feature in the second feature " on " or " down " can be with
It is that the first and second features directly contact or the first and second features pass through intermediary mediate contact.Moreover, fisrt feature exists
Second feature " on ", " top " and " above " but fisrt feature be directly above or diagonally above the second feature, or be merely representative of
First feature horizontal height is higher than second feature.Fisrt feature can be under the second feature " below ", " below " and " below "
One feature is directly under or diagonally below the second feature, or is merely representative of first feature horizontal height less than second feature.
In the description of this specification, reference term " one embodiment ", " some embodiments ", " example ", " specifically show
The description of example " or " some examples " etc. means specific features, structure, material or spy described in conjunction with this embodiment or example
Point is included at least one embodiment or example of the invention.In the present specification, schematic expression of the above terms are not
It must be directed to identical embodiment or example.Moreover, particular features, structures, materials, or characteristics described can be in office
It can be combined in any suitable manner in one or more embodiment or examples.In addition, without conflicting with each other, the skill of this field
Art personnel can tie the feature of different embodiments or examples described in this specification and different embodiments or examples
It closes and combines.
The foregoing is merely presently preferred embodiments of the present invention, is not intended to limit the invention, it is all in spirit of the invention and
Within principle, any modification, equivalent replacement, improvement and so on be should all be included in the protection scope of the present invention.
Claims (4)
1. a kind of bipolar junction transistor, including collector (8), the first N+ substrate (7), N- collecting zone (6), p-type base area (9), N
+ emitter region (3), the 2nd N+ substrate (2), emitter (1), the first base stage (4) and the second base stage (5)；
The collector (8), the first N+ substrate (7), the N- collecting zone (6) and the p-type base area (9) from bottom to up according to
Secondary to be stacked, the N+ emitter region (3) is located on the p-type base area (9), the 2nd N+ substrate (2) and the emitter
(1) it is sequentially located on the N+ emitter region (3), first base stage (4) and second base stage (5) are located at the N+ hair
The two sides of area (3) are penetrated, and are located on the p-type base area (9)；
It is characterized in that, the first N+ substrate (7) and the N- collecting zone (6) are carbofrax material, the p-type base area (9)
For silicon materials, the N+ emitter region (3) and the 2nd N+ substrate (2) are carbofrax material, the N- collecting zone (6) and described
P-type base area (9) forms hetero-junctions by bonding techniques, and the p-type base area (9) and the N+ emitter region (3) pass through bonding techniques
Form hetero-junctions.
2. a kind of bipolar junction transistor according to claim 1, which is characterized in that the doping of the p-type base area (9) is dense
Degree is 1 × 1016cm-3。
3. a kind of bipolar junction transistor according to claim 1, which is characterized in that the doping of the N+ emitter region (3)
Concentration is 1.2 × 1019cm-3。
4. a kind of bipolar junction transistor according to claim 1, which is characterized in that the doping of the N- collecting zone (6)
Concentration is 1.8 × 1015cm-3。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910850313.9A CN110534565A (en) | 2019-09-10 | 2019-09-10 | A kind of bipolar junction transistor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910850313.9A CN110534565A (en) | 2019-09-10 | 2019-09-10 | A kind of bipolar junction transistor |
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| CN110534565A true CN110534565A (en) | 2019-12-03 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116741634A (en) * | 2023-06-20 | 2023-09-12 | 中国科学院上海微系统与信息技术研究所 | Bipolar power device and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5272096A (en) * | 1992-09-29 | 1993-12-21 | Motorola, Inc. | Method for making a bipolar transistor having a silicon carbide layer |
| US20030094672A1 (en) * | 2001-11-21 | 2003-05-22 | Torvik John Tarje | Heterojunction bipolar transistor containing at least one silicon carbide layer |
| CN1589497A (en) * | 2001-11-21 | 2005-03-02 | 皇家飞利浦电子股份有限公司 | Heterojunction semiconductor device and method of manufacturing such device |
-
2019
- 2019-09-10 CN CN201910850313.9A patent/CN110534565A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5272096A (en) * | 1992-09-29 | 1993-12-21 | Motorola, Inc. | Method for making a bipolar transistor having a silicon carbide layer |
| US20030094672A1 (en) * | 2001-11-21 | 2003-05-22 | Torvik John Tarje | Heterojunction bipolar transistor containing at least one silicon carbide layer |
| CN1589497A (en) * | 2001-11-21 | 2005-03-02 | 皇家飞利浦电子股份有限公司 | Heterojunction semiconductor device and method of manufacturing such device |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116741634A (en) * | 2023-06-20 | 2023-09-12 | 中国科学院上海微系统与信息技术研究所 | Bipolar power device and preparation method thereof |
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