CN103050514A - Collector structure of power semiconductor device - Google Patents
Collector structure of power semiconductor device Download PDFInfo
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- CN103050514A CN103050514A CN2013100125483A CN201310012548A CN103050514A CN 103050514 A CN103050514 A CN 103050514A CN 2013100125483 A CN2013100125483 A CN 2013100125483A CN 201310012548 A CN201310012548 A CN 201310012548A CN 103050514 A CN103050514 A CN 103050514A
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- layer
- indium gallium
- gallium nitrogen
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- power semiconductor
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- 239000004065 semiconductor Substances 0.000 title claims abstract description 22
- 229910052738 indium Inorganic materials 0.000 claims abstract description 57
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 claims abstract description 57
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 32
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 32
- 239000010703 silicon Substances 0.000 claims abstract description 32
- 239000000758 substrate Substances 0.000 claims abstract description 29
- 229910052751 metal Inorganic materials 0.000 claims abstract description 25
- 239000002184 metal Substances 0.000 claims abstract description 25
- 229910002601 GaN Inorganic materials 0.000 claims abstract description 13
- JMASRVWKEDWRBT-UHFFFAOYSA-N Gallium nitride Chemical compound [Ga]#N JMASRVWKEDWRBT-UHFFFAOYSA-N 0.000 claims abstract description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 112
- 229910052757 nitrogen Inorganic materials 0.000 claims description 60
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 claims description 56
- 229910052733 gallium Inorganic materials 0.000 claims description 56
- 238000000576 coating method Methods 0.000 claims description 16
- 239000011248 coating agent Substances 0.000 claims description 15
- HJELPJZFDFLHEY-UHFFFAOYSA-N silicide(1-) Chemical compound [Si-] HJELPJZFDFLHEY-UHFFFAOYSA-N 0.000 claims 4
- 230000006798 recombination Effects 0.000 abstract description 2
- 230000007547 defect Effects 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 90
- 239000000463 material Substances 0.000 description 12
- 230000012010 growth Effects 0.000 description 11
- 238000000034 method Methods 0.000 description 11
- 230000005611 electricity Effects 0.000 description 5
- 239000002086 nanomaterial Substances 0.000 description 5
- 230000006872 improvement Effects 0.000 description 4
- 238000002360 preparation method Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000002070 nanowire Substances 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000005533 two-dimensional electron gas Effects 0.000 description 3
- 238000005452 bending Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 238000000407 epitaxy Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 239000002800 charge carrier Substances 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 239000002019 doping agent Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000002513 implantation Methods 0.000 description 1
- 229910001425 magnesium ion Inorganic materials 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 238000005036 potential barrier Methods 0.000 description 1
- 239000011241 protective layer Substances 0.000 description 1
- 238000005215 recombination Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
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Abstract
The invention relates to the technical field of power semiconductor devices, in particular to a collector structure of a power semiconductor device. According to the technical scheme provided by the invention, the collector structure of the power semiconductor device comprises an N-type silicon substrate layer and a collector metal layer, wherein a first indium gallium nitride layer is arranged between the N-type silicon substrate layer and the collector metal layer. The heterojunction interface in the invention has more defects, can form a recombination center to reduce the service life of a current carrier and improve the turn-off characteristic.
Description
Technical field
The present invention relates to a kind of power semiconductor technical field, especially a kind of collector structure of power semiconductor.
Background technology
In IGBT design, realize that by the mode that adopts the back side injected minority carrier electricity leads modulating action, thereby reduce the conduction voltage drop of device, but brought simultaneously the time-delay that minority carrier recombination causes when turn-offing.Therefore conduction voltage drop and turn-off time are mutually restrictions.One of the method that can improve this restricting relation is can be by increasing the intrinsic carrier concentration of device.Backing material by the growth heterojunction substitutes conventional back of the body notes technique, at the near interface of different materials, because the polarity effect that the energy gap difference causes can induce highdensity intrinsic charge carrier, thereby improves performance of devices.GaN has the energy gap much larger than Si, easily forms stronger polarized electric field, the highdensity two-dimensional electron gas of inducting.But do not allow the height that is easy to do because the P type of GaN material mixes, therefore need the thicker of growth could satisfy performance requirement.
The structure of existing non-punch power semiconductor is provided with extremely electricity district 7 of P type as shown in Figure 1 at the back side of N-type layer-of-substrate silicon 1, extremely be provided with collector electrode metal floor 2 in the back side in electricity district 7 in the P type.The structure of the power semiconductor of existing punch is provided with N-type silicon buffer layer 4 at the back side of N-type layer-of-substrate silicon 1 as shown in Figure 2, is provided with extremely electricity district 7 of P type at the back side of N-type silicon buffer layer 4, extremely is being provided with collector electrode metal floor 2 in the back side in electricity district 7 in the P type.
Chinese patent application number: 201010554510, in the epitaxially grown process of LED, the GaN material is deposited.Then, after the LED epitaxial growth is finished, carry out the deposition of transparent electrode layer.Then, post-depositional transparent electrode layer is made into latticed layer.By the existence of latticed high-k transparent electrode layer, make it as current extending and stress-buffer layer.Thus, not only improve light extraction efficiency, also improved simultaneously device reliability.What is more important, the present invention can eliminate in the future in the inner existing larger residual stress of LED epitaxial wafer, avoids coming off of LED protective layer, has promoted the total quality of LED.
The number of applying for a patent: 200480038612.4, a kind of semiconductor device with heterojunction is provided.This device comprises substrate and at least one nanostructure.Substrate is made of different materials with nanostructure.Substrate for example can be made of IV family semi-conducting material, and nanostructure can be made of III-V family semi-conducting material.Nanostructure has epitaxial relationship by substrate supports and with it.Nanostructure can be such as grid-around the functional part of the electronic device of-transistor device.Grid-around among-transistorized the embodiment, nano wire is by substrate supports, substrate is drain electrode, and nano wire is current channel, and the top metal contact is source electrode.Thin gate-dielectric separates nano wire and gate electrode.
Summary of the invention
The objective of the invention is to overcome the deficiencies in the prior art, provide a kind of and can improve injection efficiency, improve the collector structure of power semiconductor of the conduction voltage drop of device.
According to technical scheme provided by the invention, the collector structure of described a kind of power semiconductor comprises N-type layer-of-substrate silicon and collector electrode metal layer, is provided with the first indium gallium nitrogen layer between N-type layer-of-substrate silicon and collector electrode metal layer.
Between the first indium gallium nitrogen layer and N-type layer-of-substrate silicon, be provided with the N-type silicon buffer layer.
Between N-type silicon buffer layer and the first indium gallium nitrogen layer, be provided with the second resilient coating, between the first indium gallium nitrogen layer and collector electrode metal layer, be provided with the second indium gallium nitrogen layer; Described the second resilient coating is amorphous gallium nitride layer or aln layer.
Between the first indium gallium nitrogen layer and N-type layer-of-substrate silicon, be provided with the second resilient coating, between the first indium gallium nitrogen layer and collector electrode metal layer, be provided with the second indium gallium nitrogen layer; Described the second resilient coating is amorphous gallium nitride layer or aln layer.
The present invention makes heterojunction structure by the back side at device and improves injection efficiency, can improve the conduction voltage drop of device;
Among the present invention, p-type In
0Ga
1-0The doped chemical Mg ionization energy of N (Δ Ev is 250meV approximately), p-type In
1Ga
1-1The doped chemical Mg ionization energy of N (Δ Ev is 110meV approximately), so In
xGa
1-xN or In
yGa
1-yThe ionization energy of the Mg of N is approximately 44meV of p-type Si(Δ Ev) several times, Heat stability is good.
Among the present invention because In
xGa
1-xN and In
yGa
1-yThe N growth temperature is higher, can reduce the thermal process time of previous process.
Because the easier tunnelling of the two-dimensional electron gas that polarization effect produces realizes the ohmic contact of same backs dopant dose, can surpass the lower limit of the low implantation dosage in the back side in the traditional handicraft among the present invention.
Among the present invention, the heterojunction boundary defective is more, can form the complex centre and reduce carrier lifetime, improves turn-off characteristic.
Description of drawings
Fig. 1 is the non-punch voltage-controlled type power unit structure figure of prior art.
Fig. 2 is the voltage-controlled type power unit structure figure of the punch of prior art.
Fig. 3 is the structure chart of the embodiment of the invention 1.
Fig. 4 is the structure chart of the embodiment of the invention 2.
Fig. 5 is the structure chart of the embodiment of the invention 3.
Fig. 6 is the structure chart of the embodiment of the invention 4.
Embodiment
The invention will be further described below in conjunction with specific embodiment.
Among the present invention, the material of the first indium gallium nitrogen layer 3 is In
xGa
1-xN, in the formula, 0＜X＜1.
Among the present invention, the material of the second indium gallium nitrogen layer 6 is In
yGa
1-yN, in the formula, 0＜y＜1, and x ≠ y.
As shown in Figure 3, a kind of collector structure of power semiconductor comprises N-type layer-of-substrate silicon 1 and collector electrode metal layer 2, is provided with the first indium gallium nitrogen layer 3 between N-type layer-of-substrate silicon 1 and collector electrode metal layer 2.
Fig. 3 has provided improvement project of the present invention, and the doping of the P type of the collector electrode at the back side is P type In by the first indium gallium nitrogen layer 3(among Fig. 1
xGa
1-xN) replace.The back side the first indium gallium nitrogen layer 3 materials adopt the method preparation of extension, because the doping content of P type GaN can not be too high, higher the first indium gallium nitrogen layer 3 materials that therefore adopt P type concentration to do can reduce growth thickness effectively.Concentration is higher, and it is thinner that thickness can be done, to satisfy the performance requirement of identity unit.The required Mg ion that mixes can adopt and inject or obtain with the method for the first indium gallium nitrogen layer 3 synchronous growths, latter's activation of need to annealing after having grown.
Collector electrode Si is with P+ Si mark among Fig. 1.
Compare with Si, because the first indium gallium nitrogen layer 3 has long-range and carrier mobility and saturated electron drift velocity Si, therefore, indium gallium nitrogen collector electrode can have lower tagma resistance and conduction voltage drop.
Because the energy gap of the first indium gallium nitrogen layer 3 greater than the energy gap of Si, easily forms stronger polarized electric field, the highdensity two-dimensional electron gas of inducting, this is of value to the conduction voltage drop that improves device.
The acceptor level of the first indium gallium nitrogen layer 3 is darker, and temperature influence is less, can reduce the conductivity modulation effect of device temperature influence.
As shown in Figure 4, a kind of collector structure of power semiconductor, comprise N-type layer-of-substrate silicon 1 and collector electrode metal layer 2, between N-type layer-of-substrate silicon 1 and collector electrode metal layer 2, be provided with the first indium gallium nitrogen layer 3, between the first indium gallium nitrogen layer 3 and N-type layer-of-substrate silicon 1, be provided with N-type silicon buffer layer 4.
Fig. 4 has provided improvement project of the present invention, and Fig. 2 is similar, and it is P type In that the P type of the collector electrode at the back side mixes by the first indium gallium nitrogen layer 3(
xGa
1-xN) replace.The first indium gallium nitrogen layer 3 materials at the back side adopt the method preparation of extension.
Because there are lattice mismatch in the first indium gallium nitrogen layer 3 and Si, therefore according to the needs of growth quality, in technique, can improve by growth N-type silicon buffer layer 4 quality of the first indium gallium nitrogen layer 3.The concentration of the first indium gallium nitrogen layer 3 is low to be difficult to realize that ohm connects slightly, and the strained layer of growth one deck the first indium gallium nitrogen layer 3 can reduce its potential barrier, increase the probability of tunnelling, and the doping content of the first indium gallium nitrogen layer 3 can be higher than GaN, more is conducive to ohmic contact.Its thickness is also according to the difference of application demand and difference.
As shown in Figure 5, a kind of collector structure of power semiconductor comprises N-type layer-of-substrate silicon 1 and collector electrode metal layer 2, is provided with the first indium gallium nitrogen (In between N-type layer-of-substrate silicon 1 and collector electrode metal layer 2
xGa
1-xN) layer 3 is provided with N-type silicon buffer layer 4 between the first indium gallium nitrogen layer 3 and N-type layer-of-substrate silicon 1, is provided with the second resilient coating 5 between N-type silicon buffer layer 4 and the first indium gallium nitrogen layer 3, is provided with the second indium gallium nitrogen (In between the first indium gallium nitrogen layer 3 and collector electrode metal layer 2
yGa
1-yN) layer 6; Described the second resilient coating 5 is amorphous gallium nitride layer or aln layer.
Fig. 5 has provided another kind of improvement project of the present invention, compares with Fig. 4, and having inserted one deck the second resilient coating 5, the second resilient coatings 5 between N-type silicon buffer layer 4 and the first indium gallium nitrogen layer 3 is amorphous gallium nitride layer or aln layer; At the first indium gallium nitrogen (In
xGa
1-xN) be provided with the second indium gallium nitrogen (In between layer 3 and the collector electrode metal layer 2
yGa
1-yN) layer 6, in the formula, x ≠ y, the first indium gallium nitrogen (In
xGa
1-xN) layer the 3, second indium gallium nitrogen (In
yGa
1-yN) the same reative cell in the identical equipment is adopted in the growth of layer 6, N-type silicon buffer layer 4 and the second resilient coating 5, therefore can not increase preparation difficulty and the cost of technique, and can form the higher InGaN epitaxy layer of quality.The valence band of AlN material is lower than indium gallium nitrogen in addition, and the heterostructure band bending is more serious, and the electron gas of formation is more more to be conducive to improve conduction voltage drop.Because the present invention mainly improves structure, and is identical in the above part of AA ' line, so in Fig. 5, partly will not draw more than the AA ' line.
As shown in Figure 6, a kind of collector structure of power semiconductor, comprise N-type layer-of-substrate silicon 1 and collector electrode metal layer 2, between N-type layer-of-substrate silicon 1 and collector electrode metal layer 2, be provided with the first indium gallium nitrogen layer 3, between the first indium gallium nitrogen layer 3 and N-type layer-of-substrate silicon 1, be provided with the second resilient coating 5, between the first indium gallium nitrogen layer 3 and collector electrode metal layer 2, be provided with the second indium gallium nitrogen layer 6; Described the second resilient coating 5 is amorphous gallium nitride layer or aln layer.
Fig. 6 has provided another kind of improvement project of the present invention, compares with Fig. 5, has cancelled N-type silicon buffer layer 4.At the first indium gallium nitrogen (In
xGa
1-xN) be provided with the second indium gallium nitrogen (In between layer 3 and the collector electrode metal layer 2
yGa
1-yN) layer 6, in the formula, x ≠ y, the first indium gallium nitrogen (In
xGa
1-xN) layer the 3, second indium gallium nitrogen (In
yGa
1-yN) the same reative cell in the identical equipment is adopted in the growth of layer the 6 and second resilient coating 5, therefore can not increase preparation difficulty and the cost of technique, and can form the higher InGaN epitaxy layer of quality.The valence band of AlN material is lower than indium gallium nitrogen in addition, and the heterostructure band bending is more serious, and the electron gas of formation is more more to be conducive to improve conduction voltage drop.
Claims (4)
1. the collector structure of a power semiconductor comprises N-type layer-of-substrate silicon (1) and collector electrode metal layer (2), it is characterized in that: be provided with the first indium gallium nitrogen layer (3) between N-type layer-of-substrate silicon (1) and collector electrode metal layer (2).
2. the collector structure of power semiconductor as claimed in claim 1 is characterized in that: be provided with N-type silicon buffer layer (4) between the first indium gallium nitrogen layer (3) and N-type layer-of-substrate silicon (1).
3. the collector structure of power semiconductor as claimed in claim 2, it is characterized in that: between N-type silicon buffer layer (4) and the first indium gallium nitrogen layer (3), be provided with the second resilient coating (5), between the first indium gallium nitrogen layer (3) and collector electrode metal layer (2), be provided with the second indium gallium nitrogen layer (6); Described the second resilient coating (5) is amorphous gallium nitride layer or aln layer.
4. the collector structure of power semiconductor as claimed in claim 1, it is characterized in that: between the first indium gallium nitrogen layer (3) and N-type layer-of-substrate silicon (1), be provided with the second resilient coating (5), between the first indium gallium nitrogen layer (3) and collector electrode metal layer (2), be provided with the second indium gallium nitrogen layer (6); Described the second resilient coating (5) is amorphous gallium nitride layer or aln layer.
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|---|---|---|---|
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106783609A (en) * | 2016-12-23 | 2017-05-31 | 株洲中车时代电气股份有限公司 | A kind of IGBT device and preparation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102456717A (en) * | 2010-11-03 | 2012-05-16 | 英飞凌科技股份有限公司 | Semiconductor device and a method for manufacturing a semiconductor device |
| CN102593168A (en) * | 2011-01-17 | 2012-07-18 | 英飞凌科技奥地利有限公司 | Semiconductor device and a reverse conducting IGBT |
| CN102832239A (en) * | 2012-07-27 | 2012-12-19 | 无锡凤凰半导体科技有限公司 | High-pressure-resistant insulated gate bipolar transistor (IGBT) |
| CN102856356A (en) * | 2012-09-28 | 2013-01-02 | 中国科学院微电子研究所 | Terminal for semiconductor power device |
-
2013
- 2013-01-14 CN CN2013100125483A patent/CN103050514A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102456717A (en) * | 2010-11-03 | 2012-05-16 | 英飞凌科技股份有限公司 | Semiconductor device and a method for manufacturing a semiconductor device |
| CN102593168A (en) * | 2011-01-17 | 2012-07-18 | 英飞凌科技奥地利有限公司 | Semiconductor device and a reverse conducting IGBT |
| CN102832239A (en) * | 2012-07-27 | 2012-12-19 | 无锡凤凰半导体科技有限公司 | High-pressure-resistant insulated gate bipolar transistor (IGBT) |
| CN102856356A (en) * | 2012-09-28 | 2013-01-02 | 中国科学院微电子研究所 | Terminal for semiconductor power device |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106783609A (en) * | 2016-12-23 | 2017-05-31 | 株洲中车时代电气股份有限公司 | A kind of IGBT device and preparation method thereof |
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Application publication date: 20130417 |