CN102683429A - Ultra-high-current high-frequency FRD chip and manufacturing method thereof - Google Patents

Ultra-high-current high-frequency FRD chip and manufacturing method thereof Download PDF

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CN102683429A
CN102683429A CN201210182873XA CN201210182873A CN102683429A CN 102683429 A CN102683429 A CN 102683429A CN 201210182873X A CN201210182873X A CN 201210182873XA CN 201210182873 A CN201210182873 A CN 201210182873A CN 102683429 A CN102683429 A CN 102683429A
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type substrate
region
diffusion
junction depth
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CN102683429B (en
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夏禹清
高瑞彬
夏吉夫
郭永亮
潘福泉
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JINZHOU SHENGHE POWER ELECTRONIC CO Ltd
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Abstract

The invention provides an ultra-high-current high-frequency FRD (Fast Recovery Diode) chip and a manufacturing method thereof. The ultra-high-current high-frequency FRD chip comprises an N-type substrate with the thickness of 170 Mum-210 Mum and the sectional resistivity of 3 Omega/square-15 Omega/square, as well as an N<+> region and an N<++> region which are arranged on the front side of the N-type substrate, and a P<++> region arranged at the back of the N-type substrate, wherein the Delta Rho n/Rho n of the N-type substrate is smaller than or equal to 15 percent, and the base region width of a silicon wafer is larger than or equal to 1.1 times of the space charge region width; the junction depth of the N<++> region is 20 Mum-30 Mum, and the diffusion resistance Rsp+ is 0.3 Omega/square-0.5 Omega/square; and the junction depth of the P<++> region is 80 Mum-90 Mum, and the diffusion resistance is Rsp+ is 1 Omega/square-3 Omega/square. The manufacturing method comprises the following step: firstly, the N-type silicon wafer is adopted to ensure a non-punch through structure; secondly, the N<+> region is manufactured on the N-type substrate; thirdly, N<++> and P<++> diffusion are carried out on the front side and the back side of the N-type substrate, so as to form the N<++> region and the P<++> region; and fourthly, low-temperature platinum expansion is conducted and the residual minority carrier lifetime is 2-3Mus, and the four steps are carried out in the stressless state.

Description

Super-large current high frequency FRD diode chip for backlight unit and manufacture method
Technical field
The present invention relates to a kind of power semiconductor, particularly a kind of super-large current high frequency FRD diode chip for backlight unit and manufacture method.This device is the core devices of high frequency resistance welding machine, and the key equipment in the high frequency resistance welding machine big industrial circle that is automobile, steamer, aircraft, high ferro, nuclear power station etc.
Background technology
Fast recovery diode (FRD diode) is the power semiconductor of the most critical of the big industry of automation.
Resistance welder is within nearest 30 years, owing to the development of the novelty of FRD fast recovery diode is able to great development.At first at 1KH ZUnder the frequency, the FRD diode is succeeded and is developed and application.
At present, make the minimum silicon wafer thickness 0.24 of low pressure fast recovery diode,, can cause that forward voltage is excessive, power consumption is excessive for making super-large current high frequency FRD diode; And the method for control minority carrier life time, golden platinum expansion and the electron irradiation of expanding commonly used seldom considered the method for longitudinal defect CONCENTRATION DISTRIBUTION, especially seldom considers the influence of diffusion parameter and distribution longitudinally.
Therefore, existing fast recovery diode applying frequency is low, effect is low, device volume is big, and particularly strong big current signal causes severe contamination to human body.
Summary of the invention
The technical problem that the present invention will solve provides a kind of big electric current, high voltage, high, the soft recovery of applying frequency, can be used as the super-large current high frequency FRD diode chip for backlight unit and the manufacture method of the core devices of high frequency resistance welding machine.
Technical solution of the present invention is:
This super-large current high frequency FRD diode chip for backlight unit comprises N type substrate, and its special character is: the thickness of described N type substrate be 170 μ m～210 μ m, cross section resistivity be 3 Ω/ ~ 15 Ω/, be provided with N+ district, N in N type substrate face ++The district is provided with P at N type substrate back ++The district, said N +District junction depth 20 μ m～30 μ m, diffusion resistance R Sp+Be 1.6 Ω/～2.4 Ω/, N ++The junction depth in district is 20 μ m～30 μ m, diffusion resistance R Sp+Be 0.3 Ω/～0.5 Ω/, P ++The junction depth in district is 80 μ m～90 μ m, diffusion resistance R Sp+Be 1 Ω/～3 Ω/.
The manufacture method of this super-large current high frequency FRD diode chip for backlight unit, concrete steps are following:
1 silicon chip is prepared
Adopt thickness to be 170 μ m～210 μ m, cross section uniform resistivity and to be the N type silicon single crystal flake of 3 Ω/ ~ 15 Ω/ that △ ρ n/ ρ n ≦ 15% of said N type silicon single crystal flake, silicon wafer-based sector width >=1.1 times space charge sector width are guaranteed non-break-through structure;
2, N +Diffusion
On N type substrate, make N +The district, said N +District junction depth 20 μ m～30 μ m, diffusion resistance R Sp+Be 1.6 Ω/～2.4 Ω/, high two one magnitude of its concentration ratio substrate concentration, and than the low one magnitude of normal on-state concentration;
3, N ++And P ++Diffusion
N type substrate just, the back side carries out N simultaneously ++And P ++Diffusion forms N ++District and P ++District, wherein N ++The junction depth in district is 20 μ m～30 μ m, diffusion resistance R Sp+Be 0.3 Ω/～0.5 Ω/; P ++The junction depth in district is 80 μ m～90 μ m, diffusion resistance R Sp+Be 1 Ω/～3 Ω/;
4, low temperature platinum expansion
Two-sided expand boron, phosphorus simultaneously after, single face removes clean Pyrex layer, keeps the thick phosphorosilicate glass layer of another side, carries out the low temperature platinum expansion from anode surface, remaining minority carrier life time is 2 ~ 3 microseconds;
5, step 1～step 4 operates in and carries out under unstressed.
Said silicon wafer-based sector width is 1.1～1.15 times of space charge sector width.
The temperature of platinum expansion is 940 ℃, and the time is 30 minutes ~ 60 minutes.
The present invention has solved the technological difficulties of high-frequency welding with the low pressure fast recovery diode in all directions, on 10 KHz high frequency resistance welding machines, and the application of succeeding.
Because resistance welder starts frequent, environment is more abominable, has the over-voltage and over-current phenomenon to take place at any time, so FRD welding diode is had quite high snowslide Capability Requirement.Through adopting non-break-through structure, adopt low-resistivity monocrystalline as much as possible, to obtain the snowslide electric field strength of trying one's best high, improve the high snowslide ability of diode; The snowslide electric field strength of calculating is E=(3.34 ~ 2.67) 10 5V/cm, the reverse snowslide power P RSM>=100kW of the diode component of processing;
Because FRD welding diode is that (the big electric current fast recovery diode under the 200V ~ 400V) is the high frequency low-voltage, but must is the super low-power consumption under the equal electric current low-voltage.Through adopting the silicon of ultra thin silicon wafers, particularly ultra-thin base, make resistance welder meet the requirement of high-temperature resistant low power consumption levels with diode.
This ultra thin silicon wafers has thoroughly been overturned the production technology of original diode, and whole operating process is from the beginning to the end carried out under unstressed, thereby reduces the influence to reverse snowslide power.
Because adopt the silicon single crystal of cross section uniform resistivity, △ ρ n/ ρ n ≦ 15% makes the space charge region even, junction capacitance is little, is unlikely to produce excessive reverse current during shutoff, promptly excessive energy loss.
Owing to adopt the double-basis plot structure, promptly on the basis of former substrate concentration, add sub-fraction N again +The district, high two one magnitude of its concentration ratio substrate concentration, and than the low one magnitude of normal on-state concentration, thereby solved the softness problem.Because N has been arranged +The district has reduced by one of nonequilibrium carrier concentration when making conducting, and reverse recovery current is reduced, and the softness factor is increased.
Adopt low anode concentration technology, though can improve soft factor F RRS, as make F RRSBring up to 1.0 from 0.5, amplitude not enough, adopt double-basis plot structure technology after, just make F RRSImprove again more than 0.5, reach F RRS>1.5.
Platinum expansion under the situation that does not have phosphorosilicate glass to absorb, on state voltage often exceeds standard a lot, the platinum expansion when having had phosphorosilicate glass to absorb, on state voltage generally can reduce about 0.5V.
In sum, the present invention's beneficial effect compared with prior art is:
1, adopts the ultra-thin silicon monocrystalline silicon piece of N type low-resistance, cross section uniform resistivity, non-break-through structure, guarantee high snowslide ability.Though be voltage devices (200V), the snowslide ability is very high (at pulsewidth 20 μ s and rated junction temperature T JMCondition under, reverse impulse square wave snowslide power P RSM>=100kW).
2, adopt low anode concentration, double-basis plot structure to guarantee the fast soft recovery of diode component, reverse recovery characteristic: reverse recovery time trr≤5 μ s, reverse recovery current Irr≤120A, QRR Qr≤220 μ C, lay special stress on oppositely recovers soft factor F RRS≧ 1.5.
3, the low temperature platinum expansion under the thick phosphorosilicate glass of employing realizes approximate Localized Lifetime Control.Both guaranteed fast recovery, it is few that on state voltage is increased, and help soft recovery.
4, the FRD diode test philosophy and the method for employing and international joint make device meet and exceed international most advanced level.Remove the reverse voltage V of regulation RRM, reverse current I RRM, on state voltage V FM, outside trr test reverse recovery time, also carry out reverse recovery current Irr, QRR Qrr, oppositely recover soft factor F RRSAnd reverse impulse square wave snowslide power P RSMTest.
5, the super-large current high frequency FRD diode that makes has big electric current 5000A, 10KHz frequency applications, and has fast soft recovery characteristics, and high avalanche characteristic can be applicable on the resistance welder.
Description of drawings
Fig. 1 is a process chart of the present invention;
Fig. 2 is the super-large current high frequency FRD diode chip structure sketch map that makes;
Fig. 3 is the super-large current high frequency FRD diode chip for backlight unit CONCENTRATION DISTRIBUTION sketch map (corresponding embodiment 2) that makes.
Embodiment
Embodiment 1
Like Fig. 1, shown in Figure 2, this super-large current high frequency FRD diode chip for backlight unit manufacture method is following:
1, silicon chip is prepared
To adopt thickness be 170 μ m, cross section uniform resistivity and be that the N type silicon single crystal flake of 3 Ω/～5 Ω/ is as N type substrate 2; △ ρ n/ ρ n (change in resistance amount/average resistivity)=7%, silicon wafer-based sector width are 1.1 times of space charge sector widths, guarantee non-break-through structure; Carrying out silicon chip then cleans.
2, N +Diffusion
On N type substrate 2, make N +District 3, said N+ district 3 junction depths, 20 μ m, diffusion resistance R Sp+=1.6 Ω/.
3, N ++And P ++Diffusion
N type substrate 2 just, the back side carries out N simultaneously ++And P ++N is made in diffusion ++District 4 and P ++District 1, wherein N ++The junction depth in district 4 is 20 μ m, diffusion resistance R Sp+=0.3 Ω/; P ++The junction depth in district 1 is 80 μ m, diffusion resistance R Sp+=1.2 Ω/.
4, low temperature platinum expansion
Two-sided expand boron, phosphorus simultaneously after, single face removes clean Pyrex layer, keeps the thick phosphorosilicate glass layer of another side, carries out the low temperature platinum expansion from anode surface, the temperature of platinum expansion is 940 ℃, the time is 30 minutes, remaining minority carrier life time is 3 microseconds.
5, in the 1st step～the 4 step operating process, under unstressed, carry out, make super-large current high frequency FRD diode chip for backlight unit, the super-large current high frequency FRD diode chip for backlight unit that makes comprises N type substrate 2, N +District 3, N ++District 4 and P ++District 1.
6, life test, sintering, evaporation, moulding, corrosion cleaning, passivation protection make super-large current high frequency FRD diode.
Embodiment 2
Like Fig. 1, shown in Figure 2, this super-large current high frequency FRD diode chip for backlight unit manufacture method is following:
1 silicon chip is prepared
Adopt thickness be 190 μ m, cross section uniform resistivity and be the N type silicon single crystal flake of 5 Ω/～8 Ω/ as N type substrate 2, △ ρ n/ ρ n=10%, silicon wafer-based sector width are 1.12 times of space charge sector widths, guarantee non-break-through structure; Carrying out silicon chip then cleans.
2, N +Diffusion
On N type substrate 2, make N +District 3, said N +Distinguish 3 junction depths, 24 μ m, diffusion resistance R Sp+=2 Ω/;
3, N ++And P ++Perfect diffusion
N type substrate 2 just, the back side carries out N simultaneously ++And P ++Diffusion forms N ++District 4 and P ++District 1, wherein N ++The junction depth in district 4 is 25 μ m, diffusion resistance R Sp+=0.4 Ω/; P ++The junction depth in district 1 is 85 μ m, diffusion resistance R Sp+=1.5 Ω/; The super-large current high frequency FRD diode chip for backlight unit CONCENTRATION DISTRIBUTION that makes is as shown in Figure 3.
4, low temperature platinum expansion
Two-sided expand boron, phosphorus simultaneously after, single face removes clean Pyrex layer, keeps the thick phosphorosilicate glass layer of another side, carries out the low temperature platinum expansion from anode surface, the temperature of platinum expansion is 940 ℃, the time is 60 minutes, remaining minority carrier life time is 2.5 microseconds;
5, in the 1st step～the 4 step operating process, under unstressed, carry out, make super-large current high frequency FRD diode chip for backlight unit, the super-large current high frequency FRD diode chip for backlight unit that makes comprises N type substrate 2, N +District 3, N ++District 4 and P ++District 1.
6, life test, sintering, evaporation, moulding, corrosion cleaning, passivation protection make super-large current high frequency FRD diode.
Embodiment 3
1 silicon chip is prepared
Adopt thickness be 208 μ m, cross section uniform resistivity and be the N type silicon single crystal flake of 5 Ω/～15 Ω/ as N type substrate 2, △ ρ n/ ρ n=15%, silicon wafer-based sector width are 1.15 times of space charge sector widths, guarantee non-break-through structure; Carrying out silicon chip then cleans.
2, N +Diffusion
On N type substrate 2, make N +District 3, said N +Distinguish 3 junction depths, 30 μ m, diffusion resistance R Sp+=2.4 Ω/.
3, N ++And P ++Diffusion
N type substrate 2 just, the back side carries out N simultaneously ++And P ++Diffusion forms N ++District 4 and P ++District 1, wherein N ++The junction depth in district 4 is 28 μ m, diffusion resistance R Sp+=0.5 Ω/; P ++The junction depth in district 1 is 90 μ m, diffusion resistance R Sp+=2.5 Ω/.
4, low temperature platinum expansion
Two-sided expand boron, phosphorus simultaneously after, single face removes clean Pyrex layer, keeps the thick phosphorosilicate glass layer of another side, carries out the low temperature platinum expansion from anode surface, the temperature of platinum expansion is 940 ℃, the time is 45 minutes, remaining minority carrier life time is 2 microseconds.
5, be under unstressed, to operate in～the 4 step of the 1st step, make super-large current high frequency FRD diode chip for backlight unit, the super-large current high frequency FRD diode chip for backlight unit that makes comprises N type substrate 2, N +District 3, N ++District 4 and P ++District 1.
6, life test, sintering, evaporation, moulding, corrosion cleaning, passivation protection make super-large current high frequency FRD diode.
In the foregoing description, said N type silicon single crystal flake all can in △ ρ n/ ρ n ≦ 15% scope.
Super-large current high frequency FRD diode test result such as table 1 that embodiment 1～embodiment 3 makes:
Table 1 super-large current high frequency FRD diode test result
? Reverse voltage V RRM Reverse current I RRM On state voltage V FM Reverse recovery time trr Reverse recovery current Irr QRR Qrr The soft factor F of reverse recovery RRS Reverse impulse square wave snowslide power P RSM
Embodiment 1 240V 16mA 0.96V/5000A 1.6μS 80A 180μC 1.6 ≥100kW
Embodiment 2 300V 18mA 1.1 V/8000A 2.0μS 100A 200μC 1.55 ≥100kW
Embodiment 3 500V 28mA 1.2 V/10000A 2.6μS 120A 220μC 1.52 ≥100kW

Claims (4)

1. a super-large current high frequency FRD diode chip for backlight unit comprises N type substrate, it is characterized in that: the thickness of described N type substrate is that 170 μ m～210 μ m, cross section resistivity are 3 Ω/ ~ 15 Ω/, is provided with N+ district, N in N type substrate face ++The district is provided with P at N type substrate back ++The district, said N +District junction depth 20 μ m～30 μ m, diffusion resistance R Sp+Be 1.6 Ω/～2.4 Ω/, N ++The junction depth in district is 20 μ m～30 μ m, diffusion resistance R Sp+Be 0.3 Ω/～0.5 Ω/, P ++The junction depth in district is 80 μ m～90 μ m, diffusion resistance R Sp+Be 1 Ω/～3 Ω/.
2. the manufacture method of a super-large current high frequency FRD diode chip for backlight unit is characterized in that:
2.1, silicon chip prepares
Adopt thickness to be 170 μ m～210 μ m, cross section uniform resistivity and to be the N type silicon single crystal flake of 3 Ω/ ~ 15 Ω/ that △ ρ n/ ρ n ≦ 15% of said N type silicon single crystal flake, silicon wafer-based sector width >=1.1 times space charge sector width are guaranteed non-break-through structure;
2.2, N +Diffusion
On N type substrate, make N +The district, said N +District junction depth 20 μ m～30 μ m, diffusion resistance R Sp+Be 1.6 Ω/～2.4 Ω/, high two one magnitude of its concentration ratio substrate concentration, and than the low one magnitude of normal on-state concentration;
2.3, N ++And P ++Diffusion
N type substrate just, the back side carries out N simultaneously ++And P ++Diffusion forms N ++District and P ++District, wherein N ++The junction depth in district is 20 μ m～30 μ m, diffusion resistance R Sp+Be 0.3 Ω/～0.5 Ω/; P ++The junction depth in district is 80 μ m～90 μ m, diffusion resistance R Sp+Be 1 Ω/～3 Ω/;
2.4, the low temperature platinum expansion
Two-sided expand boron, phosphorus simultaneously after, single face removes clean Pyrex layer, keeps the thick phosphorosilicate glass layer of another side, carries out the low temperature platinum expansion from anode surface, remaining minority carrier life time is 2 ~ 3 microseconds;
2.5, step 2.1～step 2.4 operates in and carries out under unstressed.
3. according to the manufacture method of the said super-large current high frequency of claim 2 FRD diode chip for backlight unit, it is characterized in that: said silicon wafer-based sector width is 1.1～1.15 times of space charge sector width.
4. according to the manufacture method of the said super-large current high frequency of claim 2 FRD diode chip for backlight unit, it is characterized in that: the temperature of platinum expansion is 940 ℃, and the time is 30 minutes ~ 60 minutes.
CN201210182873.XA 2012-06-06 2012-06-06 Ultra-high-current high-frequency FRD chip and manufacturing method thereof Active CN102683429B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111668100A (en) * 2020-06-16 2020-09-15 捷捷半导体有限公司 Fast recovery diode and preparation method and application thereof

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Publication number Priority date Publication date Assignee Title
CN101188199A (en) * 2007-11-20 2008-05-28 中国振华集团永光电子有限公司 A making method for quick recovery silicon rectifying diode chip
CN101582456A (en) * 2009-07-02 2009-11-18 锦州市双合电器有限公司 Fast-recovery commutation diode used for high frequency electroplating and production method thereof
JP2010073857A (en) * 2008-09-18 2010-04-02 Toshiba Corp Method of manufacturing semiconductor device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101188199A (en) * 2007-11-20 2008-05-28 中国振华集团永光电子有限公司 A making method for quick recovery silicon rectifying diode chip
JP2010073857A (en) * 2008-09-18 2010-04-02 Toshiba Corp Method of manufacturing semiconductor device
CN101582456A (en) * 2009-07-02 2009-11-18 锦州市双合电器有限公司 Fast-recovery commutation diode used for high frequency electroplating and production method thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111668100A (en) * 2020-06-16 2020-09-15 捷捷半导体有限公司 Fast recovery diode and preparation method and application thereof
CN111668100B (en) * 2020-06-16 2023-09-12 捷捷半导体有限公司 Fast recovery diode and preparation method and application thereof

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