CN103367398B - Terminal protection ring and its manufacture method - Google Patents
Terminal protection ring and its manufacture method Download PDFInfo
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- CN103367398B CN103367398B CN201310312656.2A CN201310312656A CN103367398B CN 103367398 B CN103367398 B CN 103367398B CN 201310312656 A CN201310312656 A CN 201310312656A CN 103367398 B CN103367398 B CN 103367398B
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- limiting ring
- field limiting
- type field
- ring
- terminal protection
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Abstract
The present invention relates to field of semiconductor devices, discloses a kind of terminal protection ring and its manufacture method.In the present invention, terminal protection ring includes that least one set is located at the compound field limiting ring of Semiconductor substrate；Per group of compound field limiting ring includes at least one N-type field limiting ring and at least one p-type field limiting ring, and each p-type field limiting ring at least side connects a N-type field limiting ring and forms PN junction；The depth of N-type field limiting ring more than the p-type field limiting ring depth being connected with N-type field limiting ring 1/3rd.The depth of N-type field limiting ring is deeper, and doping concentration distribution is gentler, and PN junction area is bigger, makes the Electric Field Distribution on field limiting ring surface evenly, and then effectively improves the high pressure characteristics and reliability of device.
Description
Technical field
The present invention relates to field of semiconductor devices, more particularly to a kind of terminal protection loop technique.
Background technology
As global warming is increasingly serious, the mankind increasingly increase to green energy resource demand, power semiconductor
Importance is also more projected.In recent years, power semiconductor technology is developed rapidly.Terminal protection ring structure is power semiconductor
Important component part in device.The Main Function of terminal protection ring is to undertake device transverse electric field, it is ensured that power semiconductor device
Part pressure.Terminal protection ring design mainly has two big challenges：1）The area for reducing terminal protection ring advantageously reduces device
Production cost；2）Optimize the Electric Field Distribution at terminal protection ring so that potential is uniformly distributed, be conducive to the reliability for improving device
Property.
One of conventional terminal protection loop technique scheme is to adopt field limiting ring structure at present.Field limiting ring is by many of annular
The structure composition of p-type doping, in order to reduce the area of terminal protection ring, can add the annular of n-type doping in the side of p-type ring
Structure, the p-type field limiting ring so as to form P+N-N+P+ are superimposed the compound field limiting ring structure of N-type field limiting ring.Due to usual surface electricity
Field is made in the surface of device more than electric field in semiconductor body, conventional n-type doping ring, as shown in Figure 1.
It was found by the inventors of the present invention that current N-type field limiting ring ring is formed in device surface, generally within 0.5um, this
The field limiting ring of kind of form concentrates on surface due to PN junction interface, is not conducive to being uniformly distributed for electric field, can so as to cause device
Lean on property relatively bad.
Content of the invention
It is an object of the invention to provide a kind of terminal protection ring and its manufacture method, make the field limiting ring in terminal protection ring
The Electric Field Distribution on surface evenly, so as to effectively improve the high pressure characteristics and reliability of device.
For solving above-mentioned technical problem, embodiments of the present invention disclose a kind of terminal protection ring, including least one set
It is located at the compound field limiting ring of Semiconductor substrate；
Per group of compound field limiting ring includes at least one N-type field limiting ring and at least one p-type field limiting ring, and each p-type field
Limit ring at least side connects an above-mentioned N-type field limiting ring and forms PN junction；
The depth of the N-type field limiting ring more than the aforementioned p-type field limiting ring depth being connected with the N-type field limiting ring 1/3rd.
Embodiments of the present invention also disclose a kind of method of manufacture terminal protection ring, comprise the following steps：
Semiconductor substrate is provided；
The compound field limiting ring that least one set is located at Semiconductor substrate is generated, wherein
Per group of compound field limiting ring includes at least one N-type field limiting ring and at least one p-type field limiting ring, and each p-type field
Limit ring at least side connects an above-mentioned N-type field limiting ring and forms PN junction, and the depth of the N-type field limiting ring is more than and the N-type field
/ 3rd of the p-type field limiting ring depth of limit ring connection.
Compared with prior art, the main distinction and its effect are embodiment of the present invention：
In traditional handicraft, the maximum field of device generally occurs in device surface, in order to effectively improve between the field limiting ring of surface
Resistance to pressure, the N-type field limiting ring in terminal protection ring is formed in device surface typically.But, do so can make N-type field limiting ring
The radius of curvature of the PN junction formed with p-type field limiting ring is less, the non-uniform electric at PN junction, causes the reliability of device
Bad.In terminal protection ring proposed by the present invention, the depth of N-type field limiting ring is more than 1/3rd, N of the depth of p-type field limiting ring
The depth of type field limiting ring is deeper, and doping concentration distribution is gentler, and PN junction area is bigger, makes the Electric Field Distribution on field limiting ring surface more equal
Even, and then effectively improve the high pressure characteristics and reliability of device.
Further, depth of the depth of above-mentioned N-type field limiting ring more than the aforementioned p-type field limiting ring being connected with the N-type field limiting ring
Degree, can further such that the Electric Field Distribution at field limiting ring evenly, improve device high pressure characteristics and reliability.
Further, the symmetrical both sides for being aforementioned p-type field limiting ring of above-mentioned N-type field limiting ring, can improve device table
Face doping content, so as to improve the performance of the reactance voltage creep of device, wherein voltage creep refers to the voltage of device relatively slowly
Gradually rise or progressively decline.
Further, use phosphorus as doped chemical, the diffusion length of above-mentioned n-type doping element can be improved, more favorably
Required device architecture in formation this patent.
Further, above-mentioned N-type field limiting ring and p-type field limiting ring can be played cost-effective using identical litho pattern
Effect.
Description of the drawings
Fig. 1 is a kind of structural representation of terminal protection ring of the prior art；
Fig. 2 is a kind of structural representation of terminal protection ring in first embodiment of the invention；
Fig. 3 is a kind of structural representation of terminal protection ring in first embodiment of the invention；
Fig. 4 is a kind of structural representation of terminal protection ring in first embodiment of the invention；
Fig. 5 is a kind of schematic flow sheet of the method for manufacture terminal protection ring in second embodiment of the invention.
Specific embodiment
In the following description, in order that reader more fully understands the application and proposes many ins and outs.But, this
Even if the those of ordinary skill in field is appreciated that does not have these ins and outs and many variations based on following embodiment
And modification, it is also possible to realize each claim of the application technical scheme required for protection.
For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with enforcement of the accompanying drawing to the present invention
Mode is described in further detail.
In the present invention, in different accompanying drawings, identical reference marker represents identical or similar part.
First embodiment of the invention is related to a kind of terminal protection ring.Fig. 2 is the structural representation of the terminal protection ring.
Specifically, as shown in Fig. 2 the terminal protection ring includes that least one set is located at the Composite Field of Semiconductor substrate 3 and limits
Ring.
Per group of compound field limiting ring includes at least one N-type field limiting ring 1 and at least one p-type field limiting ring 2, and each P above-mentioned
At least side of type field limiting ring 2 connects a N-type field limiting ring 1 and forms PN junction.
The depth of the N-type field limiting ring 1 more than 2 depth of p-type field limiting ring being connected with the N-type field limiting ring 1 1/3rd.
Wherein, the depth of field limiting ring refers to the distance of the bottom of field limiting ring to semiconductor substrate surface.
Furthermore, it is to be understood that in the other embodiment of the present invention, the depth of above-mentioned N-type field limiting ring 1 can be more than with
The depth of the p-type field limiting ring 2 of the connection of N-type field limiting ring 1, as shown in Figure 3.
Depth of the depth of above-mentioned N-type field limiting ring more than the p-type field limiting ring being connected with the N-type field limiting ring, can be further
So that the Electric Field Distribution at field limiting ring is evenly, the high pressure characteristics and reliability of device are improved.
In the present embodiment, above-mentioned N-type field limiting ring 1 is distributed in the side of 2 low potential of aforementioned p-type field limiting ring.
Furthermore, it is to be understood that in the other embodiment of the present invention, above-mentioned N-type field limiting ring 1 can be symmetrically distributed in
The both sides of p-type field limiting ring 2 are stated, as shown in Figure 4.
The symmetrical both sides for being p-type field limiting ring of the N-type field limiting ring, can improve device surface doping content, so as to
Improve device reactance voltage creep performance, wherein voltage creep refer to the voltage of device relatively slowly gradually rise or progressively under
Drop.
In the present embodiment, the doped chemical of above-mentioned N-type field limiting ring 1 is phosphorus.
Use phosphorus as doped chemical, the diffusion length of n-type doping element can be improved, be more beneficial for being formed in this patent
Required device architecture.
Furthermore, it is to be understood that in the other embodiment of the present invention, doped chemical can also be with other N beyond phosphorus
Type doped chemical, such as arsenic, nitrogen etc..
In traditional handicraft, the maximum field of device generally occurs in device surface, in order to effectively improve between the field limiting ring of surface
Resistance to pressure, the N-type field limiting ring in terminal protection ring is formed in device surface typically.But, do so can make N-type field limiting ring
The radius of curvature of the PN junction formed with p-type field limiting ring is less, the non-uniform electric at PN junction, causes the reliability of device
Bad.In terminal protection ring proposed by the present invention, the depth of N-type field limiting ring is more than 1/3rd, N of the depth of p-type field limiting ring
The depth of type field limiting ring is deeper, and doping concentration distribution is gentler, and PN junction area is bigger, makes the Electric Field Distribution on field limiting ring surface more equal
Even, and then effectively improve the high pressure characteristics and reliability of device.
Second embodiment of the invention is related to a kind of method of manufacture terminal protection ring.Fig. 5 is the manufacture terminal protection ring
Method schematic flow sheet.
As shown in figure 5, the method for the manufacture terminal protection ring is comprised the following steps：
In a step 101, there is provided Semiconductor substrate.
Step 102 mainly generates the concrete step that least one set is located at the compound field limiting ring of Semiconductor substrate to step 104
Suddenly, wherein per group compound field limiting ring includes at least one N-type field limiting ring and at least one p-type field limiting ring, and each p-type field above-mentioned
Limit ring at least side connects an above-mentioned N-type field limiting ring and forms PN junction, and the depth of the N-type field limiting ring is more than and the N-type field
/ 3rd of the aforementioned p-type field limiting ring depth of limit ring connection.
Specifically, in a step 102, injection zone is defined using photoetching process.
It is appreciated that be symmetrically distributed in the compound field limiting ring structure of the both sides of p-type field limiting ring for N-type field limiting ring, can be with
Using identical litho pattern.
The N-type field limiting ring and p-type field limiting ring can play cost-effective effect using identical litho pattern.
Then into step 103, doped chemical is injected.
In this step, n-type doping element is phosphorus.
In this step, the implant angle of doped chemical is 0 degree of angle, or the implant angle of doped chemical is at 30 degree to 60
Between degree.
It is appreciated that the scope of the implant angle of doped chemical is different according to the demand of the sideways diffusion of doped chemical,
Can be within the scope of 30 degree to 60 degree, it is also possible in other scopes.Wherein, injection direction of the implant angle for doped chemical
The angle and normal of Semiconductor substrate between.
Then into step 104, the depth for controlling above-mentioned N-type field limiting ring or p-type field limiting ring by annealing process.
It is appreciated that in other embodiments of the present invention, the depth of two kinds of field limiting rings can also directly in injection doping unit
Controlled by changing Implantation Energy when plain.
Hereafter process ends.
Present embodiment is the method embodiment corresponding with first embodiment, and present embodiment can be with the first enforcement
Mode is worked in coordination enforcement.The relevant technical details that mentions in first embodiment are still effective in the present embodiment, in order to
Reduce and repeat, repeat no more here.Correspondingly, the relevant technical details that mentions in present embodiment are also applicable in the first enforcement
In mode.
Third embodiment of the present invention is related to a kind of method of manufacture terminal protection ring.In the present embodiment, terminal
The incipient stage for being fabricated to whole device manufacturing process of field limiting ring in protection ring.Field limiting ring is formed on silicon materials substrate.
In the present embodiment, first, the injection zone of N-type field limiting ring, using photoetching process, is defined, and this injection zone leads to
It is often to be made up of many annular regions.In the region of this definition, the peak width of photoresist opening is generally micro- to 50 at 0.5 micron
Between rice；The spacing of open area is generally between 10 microns to 100 microns.This distance generally depends on the voltage of device
Grade, device voltage higher grade, then this distance is bigger.In a 3300V IGBT（(Insulated Gate
Bipolar Transistor, insulated gate bipolar transistor) application example in, this spacing 200 microns to 300 microns it
Between.
After photoetching process is completed, injected using the element of n-type doping, this n-type doping element be usually phosphorus or
Arsenic, in an embodiment of the present invention, is more likely to use phosphorus as doped chemical, its purpose is to improve the n-type doping unit
The diffusion length of element, is more beneficial for forming required device architecture in the present invention.The metering of doped chemical injection generally exists
1E12cm-2Arrive 1E15cm-2Between.The angle of injection can be 0 degree of angle, or wide-angle injection, it is preferable that in this reality
The angle that injects in mode is applied between 30 degree to 60 degree.The main purpose of wide-angle injection is to increase n-type doping element
Sideways diffusion.
After the completion of the doped chemical injection of above-mentioned N-type field limiting ring, it usually needs the element that first the N-type field limiting ring is injected
Carry out one and activate the thermal process for pushing away trap.This thermal process is usually used high temperature furnace pipe and carries out.Preferably, the temperature of this annealing is usual
Between 1000 degree to 1200 degree, annealing time is generally between 30 minutes to 2 hours.
Afterwards, the manufacture of p-type field limiting ring is proceeded by, and its manufacture process is basically identical with conventional method.Main process bag
Include the injection zone that the p-type field limiting ring is defined using photoetching process, the p-type field limiting ring is injected.
After the completion of the p-type field limiting ring injection, annealing process is carried out again to the p-type field limiting ring and above-mentioned N-type field limiting ring,
The condition of this annealing process depends primarily on the design requirement of the p-type field limiting ring, it is preferable that the heat for using in the present embodiment
Process is 1100 degree, 2 hours.
Now, the compound field limiting ring structure that above-mentioned N-type field limiting ring intersects with p-type field limiting ring, and the N-type field are already defined
The depth of limit ring is generally in the depth more than 1/3rd of the p-type field limiting ring.The depth of the N-type field limiting ring can also be deeper than the P
The depth of type field limiting ring.
Finally, the other parts technique of whole device can be carried out on this basis, the formation of active area, grid can be included
The techniques such as the formation of pole, the formation of contact hole, the formation of metal.These techniques are similar with common process, and here is omitted.
In the present embodiment, above-mentioned N-type field limiting ring and p-type field limiting ring have used different litho patterns.In the present invention
Other embodiment in, for N-type field limiting ring is symmetrically distributed in the compound field limiting ring of p-type field limiting ring both sides, the N-type field limiting ring can
Identical litho pattern is used with same p-type field limiting ring, so as to play cost-effective effect.
In above described embodiment, above-mentioned N-type field limiting ring be produced on p-type field limiting ring make before.At this
In bright other embodiment, can first carry out the making of p-type field limiting ring carries out N-type field limiting ring making again.
It should be noted that in the claim and specification of this patent, such as first and second or the like relation
Term is used merely to make a distinction an entity or operation with another entity or operation, and not necessarily requires or imply
There is any this actual relation or order between these entities or operation.And, term " including ", "comprising" or its
Any other variant is intended to including for nonexcludability so that process, method, article including a series of key elements or
Equipment not only includes those key elements, but also other key elements including being not expressly set out, or also include for this process,
The intrinsic key element of method, article or equipment.In the absence of more restrictions, by wanting that sentence " including " is limited
Element, it is not excluded that also there is other identical element in process, method, article or the equipment for including the key element.
Although by referring to some preferred embodiments of the present invention, the present invention is shown and described, this
The those of ordinary skill in field should be understood that can to which, various changes can be made in the form and details, without departing from the present invention
Spirit and scope.
Claims (9)
1. a kind of terminal protection ring, it is characterised in that including the compound field limiting ring that least one set is located at Semiconductor substrate；
Per group of compound field limiting ring includes at least one N-type field limiting ring and at least one p-type field limiting ring, and each described p-type
Field limiting ring at least side connects a N-type field limiting ring and forms PN junction；
Depth of the depth of the N-type field limiting ring more than the p-type field limiting ring being connected with the N-type field limiting ring.
2. terminal protection ring according to claim 1, it is characterised in that the N-type field limiting ring is symmetrically distributed in the p-type
The both sides of field limiting ring.
3. terminal protection ring according to claim 1, it is characterised in that the N-type field limiting ring is distributed in the p-type field limit
The side of ring low potential.
4. terminal protection ring according to any one of claim 1 to 3, it is characterised in that the doping of the N-type field limiting ring
Element is phosphorus.
5. a kind of manufacture terminal protection ring method, it is characterised in that comprise the following steps：
Semiconductor substrate is provided；
The compound field limiting ring that least one set is located at Semiconductor substrate is generated, wherein
Per group of compound field limiting ring includes at least one N-type field limiting ring and at least one p-type field limiting ring, and each described p-type
Field limiting ring at least side connects the N-type field limiting ring and forms PN junction, and the depth of the N-type field limiting ring be more than with described
The depth of the p-type field limiting ring of N-type field limiting ring connection.
6. according to claim 5 manufacture terminal protection ring method, it is characterised in that the generation least one set be combined
The step of field limiting ring, also includes substep：
Injection zone is defined using photoetching process；
Injection doped chemical；
The depth that the N-type field limiting ring or p-type field limiting ring are controlled by annealing process.
7. the method for manufacture terminal protection ring according to claim 6, it is characterised in that fixed in the use photoetching process
In the step of adopted injection zone, for the N-type field limiting ring is symmetrically distributed in the Composite Field of the both sides of the p-type field limiting ring
Limit ring, using identical litho pattern.
8. the method for manufacture terminal protection ring according to claim 6, it is characterised in that in the injection doped chemical
In step, the implant angle of the doped chemical is 0 degree of angle, or the implant angle of the doped chemical 30 degree to 60 degree it
Between.
9. according to any one of claim 5 to 8 manufacture terminal protection ring method, it is characterised in that the N-type field
The doped chemical of limit ring is phosphorus.
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103531620B (en) * | 2013-10-30 | 2017-02-08 | 国家电网公司 | Insulated gate bipolar translator (IGBT) chip based on N-type injection layers and manufacturing method thereof |
| CN104409477B (en) * | 2014-11-21 | 2017-05-17 | 中国科学院微电子研究所 | Optimum design method of field-limited-ring terminal structure |
| CN105470242B (en) * | 2016-01-21 | 2018-05-08 | 上海华虹宏力半导体制造有限公司 | Sealing ring and the semiconductor structure with sealing ring |
| CN108807501B (en) * | 2018-06-05 | 2021-05-25 | 南京晟芯半导体有限公司 | Insulated gate bipolar transistor with low conduction voltage drop and preparation method thereof |
| CN114725188A (en) * | 2022-04-01 | 2022-07-08 | 无锡市谷峰半导体有限公司 | IGBT terminal capable of reducing field limiting ring width and preparation method thereof |
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| JP2002184783A (en) * | 2000-12-14 | 2002-06-28 | Nec Yamagata Ltd | Method of manufacturing semiconductor device |
| CN101017823A (en) * | 2006-12-08 | 2007-08-15 | 广州南科集成电子有限公司 | Vertical self-align suspending drain MOS audion and its making method |
| CN102969343A (en) * | 2012-10-22 | 2013-03-13 | 上海集成电路研发中心有限公司 | Protection ring structure of high pressure devices and manufacturing method thereof |
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| JP2010114250A (en) * | 2008-11-06 | 2010-05-20 | Renesas Technology Corp | Semiconductor device manufacturing method |
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|---|---|---|---|---|
| JP2002184783A (en) * | 2000-12-14 | 2002-06-28 | Nec Yamagata Ltd | Method of manufacturing semiconductor device |
| CN101017823A (en) * | 2006-12-08 | 2007-08-15 | 广州南科集成电子有限公司 | Vertical self-align suspending drain MOS audion and its making method |
| CN102969343A (en) * | 2012-10-22 | 2013-03-13 | 上海集成电路研发中心有限公司 | Protection ring structure of high pressure devices and manufacturing method thereof |
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