CN104112782A - Anti-crosstalk reverse-U-shaped buried layer photodiode and generation method - Google Patents
Anti-crosstalk reverse-U-shaped buried layer photodiode and generation method Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 22
- 230000005684 electric field Effects 0.000 claims abstract description 17
- 239000000758 substrate Substances 0.000 claims abstract description 10
- 238000002513 implantation Methods 0.000 claims description 59
- HAYXDMNJJFVXCI-UHFFFAOYSA-N arsenic(5+) Chemical compound [As+5] HAYXDMNJJFVXCI-UHFFFAOYSA-N 0.000 claims description 31
- 206010070834 Sensitisation Diseases 0.000 claims description 26
- 230000008313 sensitization Effects 0.000 claims description 26
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- 230000003071 parasitic effect Effects 0.000 claims description 8
- 230000015572 biosynthetic process Effects 0.000 claims description 7
- 229910052757 nitrogen Inorganic materials 0.000 claims description 7
- 229910052796 boron Inorganic materials 0.000 claims description 6
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- 229910052698 phosphorus Inorganic materials 0.000 claims description 2
- 239000011574 phosphorus Substances 0.000 claims description 2
- 238000009792 diffusion process Methods 0.000 abstract description 4
- 230000009471 action Effects 0.000 abstract description 2
- 230000007246 mechanism Effects 0.000 abstract description 2
- 230000006698 induction Effects 0.000 abstract 5
- 239000000969 carrier Substances 0.000 abstract 2
- -1 boron ion Chemical class 0.000 description 13
- 150000002500 ions Chemical class 0.000 description 11
- 230000000694 effects Effects 0.000 description 8
- 239000012535 impurity Substances 0.000 description 8
- 238000002347 injection Methods 0.000 description 8
- 239000007924 injection Substances 0.000 description 8
- 230000035755 proliferation Effects 0.000 description 4
- 238000012546 transfer Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 2
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- 238000002955 isolation Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
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- 230000009286 beneficial effect Effects 0.000 description 1
- 239000002800 charge carrier Substances 0.000 description 1
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- 238000013461 design Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
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- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000005468 ion implantation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
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- 230000007480 spreading Effects 0.000 description 1
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Abstract
The invention discloses an anti-crosstalk reverse-U-shaped buried layer photodiode and a generation method. The anti-crosstalk reverse-U-shaped buried layer photodiode comprises a surface P+ clamping layer on the upper portion of a P-type epitaxial layer, an initial N-type light induction area arranged on the lower portion of the P-type epitaxial layer, two ring-shaped P-type light dope buried layers arranged below the initial N-type light induction area, and secondary N-shaped light induction buried layers arranged in the ring-shaped P-type light dope buried layers. According to the anti-crosstalk reverse-U-shaped buried layer photodiode and the generation method, a built-in electric field where the P-type light dope buried layer to the P-type epitaxial layer is established, so that carriers stimulated by long-band incident light produced in the epitaxial layer and a substrate are drifted to a top layer light induction N buried layer under the action of forces of the built-in electric field and collected, transverse diffusion of charges is prevented, and a charge crosstalk phenomenon is inhibited; reduction of a charge crosstalk rate, produced by a diffusion mechanism, of the carriers stimulated by long-band light between adjacent pixel units can be guaranteed under the condition that filling factors in the light induction area are not lost, and key indexes of full trap capacity, quantum efficiency and the like are improved.
Description
Technical field
The invention belongs to cmos image sensor field, particularly a kind of anti-crosstalk inverted U buried regions photodiode and generation method.
Background technology
Cmos image sensor is with its low-power consumption, low cost and can progressively replace CCD with advantages such as cmos semiconductor integrated circuit fabrication process compatibilities and occupy imageing sensor mainstream market.Adopt clamper photodiode (PPD) further to reduce the indexs such as reset noise, dark current, fixed pattern noise of transducer for the dot structure of photosensitive unit, and can pass through Correlated Double Sampling compensating image quality, these advantages are widely used in modern high performance cmos image sensor PPD pixel.
Conventional PPD image element circuit selects switch jointly to form by a clamper photodiode, floating empty diffusion node, transfer tube, reset transistor, source follower and row, clamper photodiode is the N buried regions injecting by P type epitaxial loayer, surface P+ clamper layer and P type epitaxial loayer form jointly, this photoelectric diode structure is used for receiving incident photon, and the generation signal charge output corresponding with incident light light intensity and wavelength, the injection of P trap is in order to suppress the horizontal expansion of sensitization depletion region.
Along with the progress of CMOS technique, cmos image sensor pixel cell size is dwindled, and integration density increases, make the physical distance between neighbor more and more less, cause serious crosstalk effect, cause output image resolution and uniformity to reduce, affect image quality.So-called crosstalk effect, can be divided into two classes, and a class is that light arrived adjacent pixel location or the layer reflection of process connected medium and refraction and enters neighbor photosensitive area before being completely absorbed, and is called optical crosstalk; Another kind of is that light incides substrate and excites electric charge, before spreading go back to depletion layer uptake zone, there is certain probability generation horizontal proliferation and enter neighbor sensitization uptake zone and be collected in it, being called electric charge crosstalks, especially for compared with long-wave band light, it absorbs the degree of depth far below depletion layer uptake zone, and electric charge crosstalk phenomenon can be more remarkable.Therefore consider the impact of crosstalk effect, above-mentioned conventional PPD dot structure will be subject to the interference of neighbor, reduces image analytic degree, has certain limitation in application.
The achievement of both at home and abroad the existing part of the research of crosstalk effect being published at present, particularly for electric charge, crosstalk, some solutions have been proposed, be summarized as three kinds: the first is between neighbor, to increase active area and inject P+ guard ring, for resulting from the photogenerated charge of substrate, provide the low-resistance path of releasing, make it cannot diffuse to other pixels, the method can significantly increase sensor chip area, is also unfavorable for the design of photosensitive area fill factor, curve factor; The second is the doping content that increases epitaxial loayer, reduce minority carrier lifetime and diffusion length, make electric charge compound before diffusing to neighbor sensitization uptake zone, its drawback is that the increase of P type epitaxial layer concentration is unfavorable for that depletion region extends to epitaxial loayer, affect the absorption of long-wave band light, reduced quantum efficiency, made transducer spectrum response range limited; The third is to adopt deep trench isolation technique (DTI), and pixel cell is carried out to electrical isolation, and the method is limited to technological level, has also increased dark current generation rate, is more difficult to get extensive use.
Summary of the invention
The object of the invention is to overcome above-mentioned deficiency, a kind of anti-crosstalk inverted U buried regions photodiode and generation method are provided, can guarantee under the prerequisite of not loss photosensitive area fill factor, curve factor, reduce between adjacent pixel unit compared with the electric charge of the long-wave band photoexcitation carrier rate of crosstalking, and promote the pixel Key Performance Indicators such as full trap ability, quantum efficiency, make transducer that high-res, high-quality image can be provided.
In order to achieve the above object, a kind of anti-inverted U buried regions photodiode of crosstalking of the present invention, comprise P type epitaxial loayer and at the P of its underpart type substrate, P type epitaxial loayer top is provided with surperficial P+ clamper layer, P+ clamper layer bottom, surface is provided with initial N-type photosensitive area, below, initial N-type photosensitive area is provided with the P type light dope buried regions of two-layer annular, and P type light dope buried regions ring-shaped inner part is provided with secondary N-type sensitization buried regions.
A generation method for the anti-inverted U buried regions photodiode of crosstalking, comprises the following steps:
Step 1: inject arsenic ion and form initial N-type photosensitive area in P type epitaxial loayer;
Step 2: the B Implanted ion on initial N-type photosensitive area forms P+ clamper layer;
Step 3: use LP mask blank to inject than arsenic ion projected range head's N-type foreign ion with the surrounding of epitaxial loayer intersection below initial N-type photosensitive area, form LP1 region, implantation dosage scope is 2 * 10
11cm
-2～3 * 10
11cm
-2, Implantation Energy scope is 650keV～850keV;
Step 4: inject than arsenic ion projected range head's N-type foreign ion below LP1 region, form LP2 region, LP1 region and LP2 region form longitudinal ring-shaped P type light dope buried regions, and produce internal electric field, and implantation dosage scope is 2 * 10
11cm
-2～3 * 10
11cm
-2, Implantation Energy scope is 1300keV～1600keV;
Step 5: use Sn mask blank that arsenic ion is injected to P type light dope buried regions ring-shaped inner part, form secondary N-type sensitization buried regions, secondary N-type sensitization buried regions and P type light dope buried regions produce sidewall parasitic capacitance, and final formation resists the inverted U buried regions photodiode of crosstalking.
In described step 1, the doping content of P type epitaxial loayer is 1 * 10
15cm
-3.
The dosage range that injects arsenic ion in described step 1 is 5 * 10
12cm
-2～7 * 10
12cm
-2, Implantation Energy scope is 60keV～100keV.
In described step 2, the implantation dosage scope of boron ion is 8 * 10
12cm
-2～1 * 10
13cm
-2, Implantation Energy scope is 5keV～8keV.
Described step 3 and step 4 Zhong Bi arsenic ion projected range head's N-type foreign ion is nitrogen or phosphorus.
In described step 5, arsenic ion implantation dosage scope is 8 * 10
11cm
-2～12 * 10
11cm
-2, Implantation Energy scope is 200keV～300keV.
Compared with prior art, a kind of anti-inverted U buried regions photodiode of crosstalking of the present invention has following beneficial effect:
1) the present invention does not affect pixel photosensitive area and fill factor, curve factor, does not increase the area of sensor chip yet;
2) injection of secondary light-sensitive N buried regions of the present invention is further extended depletion layer to substrate, and the degree of depth that incident light can effectively be absorbed is darker, therefore has higher long-wave band illumination quantum efficiency;
3) secondary N-type sensitization buried regions quilt of the present invention " embedded " is in P type light dope buried regions, be equivalent to is only that the central region of initial N-type photosensitive area is extended to P type epitaxial loayer, and the reason because of the distribution of impurity concentration gradient, secondary N-type sensitization buried regions doping content is lower, therefore can, in the ability that exhausts that to a certain degree keeps initial N-type sensitization buried regions, be difficult for producing " streaking " phenomenon that former frame signal charge remains to next frame.
Further, a kind of anti-inverted U buried regions photodiode of crosstalking of the present invention has re-injected secondary N-type sensitization buried regions below initial N-type photosensitive area, has increased photodiode sidewall parasitic capacitance, and then has increased full trap electric charge ability.
The generation method of a kind of anti-inverted U buried regions photodiode of crosstalking of the present invention, by inject high-energy low dosage N-type impurity around with P type epitaxial loayer epitaxial loayer intersection below initial N-type photosensitive area, realize the impurity compensation with P type epitaxial loayer, the P type light dope buried regions that generation is lower than P type epitaxial layer concentration, and and P type epitaxial loayer between form concentration gradient, set up the internal electric field that is pointed to P type epitaxial loayer by P type light dope buried regions, making to result from epitaxial loayer and substrate the effect that is subject to internal electric field power compared with the light activated charge carrier of long-wave band incident drifts about and is collected to top layer sensitization N buried regions, stoped the horizontal proliferation of electric charge, electric charge crosstalk phenomenon is inhibited.
Accompanying drawing explanation
Fig. 1 is traditional 4T active pixel circuit diagram;
Fig. 2 is the conventional P PD structure charge mechanism of crosstalking;
Fig. 3 is the present invention's two step doped with P type structural representations;
Fig. 4 is that secondary N-type sensitization buried regions of the present invention injects schematic diagram;
Fig. 5 is photosensitive area of the present invention domain schematic diagram.
Embodiment
Below in conjunction with accompanying drawing, the present invention will be further described.
Referring to Fig. 3, Fig. 4 and Fig. 5, a kind of anti-inverted U buried regions photodiode of crosstalking of the present invention, comprise P type epitaxial loayer 130 and at the P of its underpart type substrate 200, P type epitaxial loayer 130 tops are provided with surperficial P+ clamper layer 100, P+ clamper layer 100 bottom, surface are provided with initial N-type photosensitive area 110,110 belows, initial N-type photosensitive area are provided with the P type light dope buried regions of two-layer annular, and P type light dope buried regions ring-shaped inner part is provided with secondary N-type sensitization buried regions 410.
Embodiment 1:
Step 1: be 1 * 10 in doping content
15cm
-3the interior injection arsenic ion of P type epitaxial loayer 130 form initial N-type photosensitive area 110, the dosage that injects arsenic ion is 5 * 10
12cm
-2, Implantation Energy is 60keV;
Step 2: B Implanted ion forms P+ clamper layer 100 on initial N-type photosensitive area 110, and the implantation dosage of boron ion is 8 * 10
12cm
-2, Implantation Energy is 5keV;
Step 3: inject phosphonium ion with the use LP of the surrounding mask blank 520 of epitaxial loayer intersection below initial N-type photosensitive area 100, form LP1 region 320, implantation dosage is 2.2 * 10
11cm
-2～, Implantation Energy is 700keV;
Step 4: inject nitrogen or phosphonium ion below LP1 region 320, form LP2 region 321,320YuLP2 region, LP1 region 321 forms longitudinal ring-shaped P type light dope buried regions, and produces internal electric field, and implantation dosage is 3 * 10
11cm
-2, Implantation Energy is 1600keV;
Step 5: use Sn mask blank that arsenic ion 411 is injected to P type light dope buried regions ring-shaped inner part, arsenic ion 411 implantation dosages are 8 * 10
11cm
-2, Implantation Energy is 200keV, forms secondary N-type sensitization buried regions 410, secondary N-type sensitization buried regions 410 produces sidewall parasitic capacitance 420 with P type light dope buried regions, the anti-inverted U buried regions photodiode of crosstalking of final formation.
Embodiment 2:
Step 1: be 1 * 10 in doping content
15cm
-3the interior injection arsenic ion of P type epitaxial loayer 130 form initial N-type photosensitive area 110, the dosage that injects arsenic ion is 5 * 10
12cm
-2, Implantation Energy is 60keV;
Step 2: the B Implanted ion on initial N-type photosensitive area 110 forms P+ clamper layer 100, and the implantation dosage of boron ion is 8 * 10
12cm
-2, Implantation Energy is 5keV;
Step 3: inject phosphonium ion with the use LP of the surrounding mask blank 520 of epitaxial loayer intersection below initial N-type photosensitive area 100, form LP1 region 320, implantation dosage is 2 * 10
11cm
-2, Implantation Energy is 650keV;
Step 4: inject nitrogen or phosphonium ion below LP1 region 320, form LP2 region 321,320YuLP2 region, LP1 region 321 forms longitudinal ring-shaped P type light dope buried regions, and produces internal electric field, and implantation dosage is 2 * 10
11cm
-2, Implantation Energy is 1300keV;
Step 5: use Sn mask blank that arsenic ion 411 is injected to P type light dope buried regions ring-shaped inner part, arsenic ion 411 implantation dosages are 8 * 10
11cm
-2, Implantation Energy is 200keV, forms secondary N-type sensitization buried regions 410, secondary N-type sensitization buried regions 410 produces sidewall parasitic capacitance 420 with P type light dope buried regions, the anti-inverted U buried regions photodiode of crosstalking of final formation.
Embodiment 3:
Step 1: be 1 * 10 in doping content
15cm
-3the interior injection arsenic ion of P type epitaxial loayer 130 form initial N-type photosensitive area 110, the dosage that injects arsenic ion is 7 * 10
12cm
-2, Implantation Energy is 100keV;
Step 2: the B Implanted ion on initial N-type photosensitive area 110 forms P+ clamper layer 100, and the implantation dosage of boron ion is 1 * 10
13cm
-2, Implantation Energy is 8keV;
Step 3: with the use LP of surrounding mask blank 520 injecting nitrogen ions of epitaxial loayer intersection, form LP1 region 320 below initial N-type photosensitive area 100, implantation dosage is 3 * 10
11cm
-2, Implantation Energy is 850keV;
Step 4: inject nitrogen or phosphonium ion below LP1 region 320, form LP2 region 321,320YuLP2 region, LP1 region 321 forms longitudinal ring-shaped P type light dope buried regions, and produces internal electric field, and implantation dosage is 3 * 10
11cm
-2, Implantation Energy is 1600keV;
Step 5: use Sn mask blank that arsenic ion 411 is injected to P type light dope buried regions ring-shaped inner part, arsenic ion 411 implantation dosages are 12 * 10
11cm
-2, Implantation Energy is 300keV, forms secondary N-type sensitization buried regions 410, secondary N-type sensitization buried regions 410 produces sidewall parasitic capacitance 420 with P type light dope buried regions, the anti-inverted U buried regions photodiode of crosstalking of final formation.
Embodiment 4:
Step 1: be 1 * 10 in doping content
15cm
-3the interior injection arsenic ion of P type epitaxial loayer 130 form initial N-type photosensitive area 110, the dosage that injects arsenic ion is 6 * 10
12cm
-2, Implantation Energy is 80keV;
Step 2: the B Implanted ion on initial N-type photosensitive area 110 forms P+ clamper layer 100, and the implantation dosage of boron ion is 9 * 10
12cm
-2, Implantation Energy is 7keV;
Step 3: inject phosphonium ion with the use LP of the surrounding mask blank 520 of epitaxial loayer intersection below initial N-type photosensitive area 100, form LP1 region 320, implantation dosage is 1.5 * 10
11cm
-2, Implantation Energy is 750keV;
Step 4: inject nitrogen or phosphonium ion below LP1 region 320, form LP2 region 321,320YuLP2 region, LP1 region 321 forms longitudinal ring-shaped P type light dope buried regions, and produces internal electric field, and implantation dosage is 1.5 * 10
11cm
-2, Implantation Energy is 1450keV;
Step 5: use Sn mask blank that arsenic ion 411 is injected to P type light dope buried regions ring-shaped inner part, arsenic ion 411 implantation dosages are 10 * 10
11cm
-2, Implantation Energy is 150keV, forms secondary N-type sensitization buried regions 410, secondary N-type sensitization buried regions 410 produces sidewall parasitic capacitance 420 with P type light dope buried regions, the anti-inverted U buried regions photodiode of crosstalking of final formation.
The present invention, by the inhibition of compromise crosstalk effect and maintenance and the improvement of other main pixel performance indexs, has done following two step architecture advances: step 1 is to inject respectively longitudinal P type light dope buried structure in the surrounding of initial 110 belows, N-type photosensitive area (ON) and epitaxial loayer intersection; Step 2 is between P type light dope buried regions, to inject secondary N-type sensitization buried regions, forms inverted U structure with P type light dope buried regions.
As shown in Figure 3, in the generation method of P type light dope buried regions, the injection P type of looking for novelty concentration will be lower than the doping content of P type epitaxial loayer, therefore need be according to impurity compensation principle, the different N-type foreign ion 311 of Implantation Energy compensates the acceptor ion in P type epitaxial loayer in two steps, and it is identical that two steps are injected mask plate.The selection of this N-type ionic type must be the ion that atomic number is less than initial N buried regions impurity, to obtain darker projected range.First step implantation dosage is 2 * 10
11cm
-2～3 * 10
11cm
-2, energy is 650keV～850keV, forms LP1 region; Second step implantation dosage is 2 * 10
11cm
-2～3 * 10
11cm
-2, energy is 1300keV～1600keV, forms LP2 region, and the formation of LP1 and LP2 buried regions makes between LP region and P type epitaxial loayer 130, to have set up the deep layer electric field 330 that is pointed to P type epitaxial loayer by P type light dope buried regions, and its electric field strength can be expressed as:
Wherein, k
0for Boltzmann constant; T is temperature; Q is unit charge amount; N
ePIand N
lPbe respectively the doping content of P type epitaxial loayer and P type light dope buried regions; z
hLwidth for newly-built electric field action zone.This electric field provides steady electric field power for resulting from P type epitaxial loayer 130 photo-generated carrier 240, makes its drift quick uptake zone of light echo, thereby reduces by 240 horizontal proliferation of superfluous photo-generated carrier to the probability of neighbor uptake zone, has suppressed electric charge and has crosstalked.In addition, electric field 331 effects that the concentration gradient that the minority that results from substrate 200 also can not formed by epitaxial loayer and substrate by compound photo-generated carrier 250 produce are drifted about back in epitaxial loayer and are absorbed by photosensitive area.
It should be noted that, from formula (1), lower LP doping content can make newly-built electric field stronger, the inhibitory action that electric charge is crosstalked is also larger, but when LP doping content enough low and while reaching transoid critical point, this region epitaxial loayer likely transoid is N-type, cause unnecessary initial N buried regions extension and exhaust ability weak, cause N buried regions pinch-off voltage to raise, be unfavorable for that electric charge shifts completely, easily cause streaking phenomenon.Therefore, LP region should not transoid become N-type.
As shown in Figure 4 and Figure 5, in the generation method of secondary N-type sensitization buried regions, adopt the N-type Implantation 411 of a higher-energy, this ionic type is same with initial N buried regions 110 impurity phases, its mask plate photoetching window ranges is positioned at the inside in LP region, and with LP mask plate inside window edge keep apart certain distance 510, object is to be the dark impurity horizontal proliferation reserved location forming that injects, and reduces secondary N buried regions 410 and LP region impurity compensation effect.The injection of secondary N buried regions 410 is extended initial N buried regions, has produced secondary N buried regions 410 as shown in Figure 4 and sidewall parasitic capacitance 420 between LP, has expanded full trap capacity.And the extension of initial N buried regions also makes depletion region 210 occur extending 211 below secondary N buried regions 410, photo-generated carrier drift collected volume is expanded, medium-long wave band illumination quantum efficiency is effectively promoted.
It should be noted that, in 4T dot structure, signal charge amount can only be determined by reading the quantity of electric charge that FD orders, therefore effectively completely the maximum amount of charge that trap capacity should can receive for FD point, this is transferred to the transfer efficiency problem of FD with regard to involving electric charge by PPD, transfer efficiency is larger, and the signal swing that can effectively be read is just larger.The doping content in secondary N buried regions 410 regions need be as far as possible low like this, and should not be extended down to deeply, to keep the ability that exhausts of whole n-quadrant, is unlikely to make pinch-off voltage to raise and causes charge transfer effciency to reduce.Therefore, SN implantation dosage is chosen as 8 * 10
11cm
-2～12 * 10
11cm
-2, Implantation Energy is chosen as 200keV～300keV.
Claims (7)
1. one kind resists the inverted U buried regions photodiode of crosstalking, it is characterized in that: comprise P type epitaxial loayer (130) and at the P of its underpart type substrate (200), P type epitaxial loayer (130) top is provided with surperficial P+ clamper layer (100), P+ clamper layer (100) bottom, surface is provided with initial N-type photosensitive area (110), below, initial N-type photosensitive area (110) is provided with the P type light dope buried regions of two-layer annular, and P type light dope buried regions ring-shaped inner part is provided with secondary N-type sensitization buried regions (410).
2. resist a generation method for the inverted U buried regions photodiode of crosstalking, it is characterized in that: comprise the following steps:
Step 1: inject arsenic ion and form initial N-type photosensitive area (110) in P type epitaxial loayer (130);
Step 2: the B Implanted ion on initial N-type photosensitive area (110) forms P+ clamper layer (100);
Step 3: inject than arsenic ion projected range head's N-type foreign ion with the use LP of the surrounding mask blank (520) of epitaxial loayer intersection in below, initial N-type photosensitive area (100), form LP1 region (320), implantation dosage scope is 2 * 10
11cm
-2～3 * 10
11cm
-2, Implantation Energy scope is 650keV～850keV;
Step 4: inject than arsenic ion projected range head's N-type foreign ion in LP1 region (320) below, form LP2 region (321), LP1 region (320) forms longitudinal ring-shaped P type light dope buried regions with LP2 region (321), and producing internal electric field, implantation dosage scope is 2 * 10
11cm
-2～3 * 10
11cm
-2, Implantation Energy scope is 1300keV～1600keV;
Step 5: use Sn mask blank that arsenic ion (411) is injected to P type light dope buried regions ring-shaped inner part, form secondary N-type sensitization buried regions (410), secondary N-type sensitization buried regions (410) produces sidewall parasitic capacitance (420) with P type light dope buried regions, and final formation resists the inverted U buried regions photodiode of crosstalking.
3. the generation method of a kind of anti-inverted U buried regions photodiode of crosstalking according to claim 3, is characterized in that: in described step 1, the doping content of P type epitaxial loayer (130) is 1 * 10
15cm
-3.
4. the generation method of a kind of anti-inverted U buried regions photodiode of crosstalking according to claim 3, is characterized in that: the dosage range that injects arsenic ion in described step 1 is 5 * 10
12cm
-2～7 * 10
12cm
-2, Implantation Energy scope is 60keV～100keV.
5. the generation method of a kind of anti-inverted U buried regions photodiode of crosstalking according to claim 3, is characterized in that: in described step 2, the implantation dosage scope of boron ion is 8 * 10
12cm
-2～1 * 10
13cm
-2, Implantation Energy scope is 5keV～8keV.
6. the generation method of a kind of anti-inverted U buried regions photodiode of crosstalking according to claim 3, is characterized in that: described step 3 and step 4 Zhong Bi arsenic ion projected range head's N-type foreign ion is nitrogen or phosphorus.
7. the generation method of a kind of anti-inverted U buried regions photodiode of crosstalking according to claim 3, is characterized in that: arsenic ion in described step 5 (411) implantation dosage scope is 8 * 10
11cm
-2～12 * 10
11cm
-2, Implantation Energy scope is 200keV～300keV.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410353580.2A CN104112782B (en) | 2014-07-23 | 2014-07-23 | Anti-crosstalk reverse-U-shaped buried layer photodiode and generation method |
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| CN108281440A (en) * | 2018-01-24 | 2018-07-13 | 德淮半导体有限公司 | Imaging sensor and its manufacturing method |
| CN109244097A (en) * | 2018-09-25 | 2019-01-18 | 德淮半导体有限公司 | Imaging sensor and forming method thereof |
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