CN102024829B - Image sensor structure and manufacture method thereof - Google Patents
Image sensor structure and manufacture method thereof Download PDFInfo
- Publication number
- CN102024829B CN102024829B CN200910174746.3A CN200910174746A CN102024829B CN 102024829 B CN102024829 B CN 102024829B CN 200910174746 A CN200910174746 A CN 200910174746A CN 102024829 B CN102024829 B CN 102024829B
- Authority
- CN
- China
- Prior art keywords
- image sensor
- array
- dielectric layer
- sensor structure
- shielding layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Solid State Image Pick-Up Elements (AREA)
- Transforming Light Signals Into Electric Signals (AREA)
Abstract
The invention discloses an image sensor structure and a manufacture method thereof for avoiding or lightening a shadow effect. The image sensor structure comprises a substrate, a sensing element array, a dielectric layer, a bottom layer, an optical filter array and a micro lens array, wherein the sensing element array is arranged on the surface of the substrate; the dielectric layer covers the sensing element array and comprises an upper surface comprising a concave disk structure; the bottom layer is filled in the concave disk structure and has a refractive index which is greater than that of the dielectric layer; the optical filter array is arranged on the bottom layer and corresponds to the sensing element array; and the micro lens array is correspondingly arranged on the optical filter array. In the image sensor structure, the micro lens array can be arranged after a top layer covering optical filter array is arranged.
Description
Technical field
The present invention relates to a kind of image sensor structure and manufacture the method for this image sensor structure, particularly a kind of method that can improve the image sensor structure of shadow effect problem and manufacture this image sensor structure.
Background technology
For example, for digital imaging apparatus (: digital camera, digital camera), how improving image quality is the large emphasis in design.The image being produced by the image sensor of conventional digital imaging device, its middle body is conventionally bright compared with its peripheral part, this phenomenon is called as shadow effect (lens shadingeffect) or surrounding dark angle (vignetting) phenomenon, this is owing to penetrating when light after the camera lens of digital imaging apparatus, the principal angle of incidence that is incident to sensor construction is too large, make photoinduction inconsistent due to.If find, maximum principal angle of incidence is 20 degree, the brightness of image periphery be image center brightness 78% or still less.Therefore in known technology, there is method miscellaneous to alleviate the impact of shadow effect on image.
Fig. 1 shows the generalized section of known CMOS image sensor structure.CMOS image sensor structure 10; wherein light sensitive diode (photodiode) 12 is formed in the surface of substrate (substrate) 14; the metal conductor layer 16,18 of three layers and 20 is covered by protective layer (passivation layer) 22; then on each protective layer 22, cover dielectric layer 24 and planarization; on the dielectric layer 24 of the Zai Yu the superiors, form even thickness and smooth bottom (under layer) 26 haply; and on bottom 26, form colored filter 28, for example Red lightscreening plate 30, green color filter 32 and blue color filter 34.On colored filter 28, form again top layer 27.On top layer (top layer) 27, form lenticule 36.Such structure, the length of focal length is enough to the light sensitive diode 12 in substrate 14 surfaces for light focusing, so shadow effect not obvious.
Yet, along with the compact demand of digital imaging apparatus, must make focal length shorten, thereby the also increase thereupon of the angle of principal angle of incidence (chief-ray angle), so produce shadow effect.The schematic diagram that known CMOS image sensor is as shown in Figure 2 combined with camera lens module.Light sensitive diode 12 is arranged in the surface 15 of substrate 14, for the succinct readability of accompanying drawing, does not show whole light sensitive diodes, each layer of dielectric layer or protective layer and intraconnections.As shown in the figure, when focal length is relatively too short, light 38 is from camera lens module 40 incidents, the light of arrival marginal position focuses to A or A ' point via the lenticule 42 or 43 at edge by top layer 27, colored filter 28, bottom 26 and dielectric layer 46, the light that arrives centre position focuses to the B point at center by top layer 27, colored filter 28, bottom 26 and dielectric layer 46 via middle lenticule 44, can find B point and A or position at A ' not at grade, the relatively recessed degree of depth of B point.The line that camber line 48 approximate focus points are linked to be.With a face, the formed face of focus point is concave surface, differs a depth d with the horizontal surface 15 of the substrate 14 at light sensitive diode 12 places, causes the inconsistent of photoinduction, makes image around darker.
Fig. 3 shows the method for the above-mentioned shadow effect of known improvement, utilize the past interior migration (microlens shift) of microlens location and/or the past external migration (color filter shift) of colored filter position, make the light sensitive diode position laminating as far as possible in formed of focus point and substrate surface, reduce locational difference, this means, make depth d ' value (B ' point) is zero as far as possible.But along with focal length needs shorter requirement, principal angle of incidence is larger, the distance of lenticule or colored filter migration is limited, does not enough correct the difference of focal position, and still have shadow effect, exists.
Therefore, still need a kind of image sensor structure of novelty, can be compact, but do not have shadow effect.
Summary of the invention
The object of this invention is to provide a kind of image sensor structure, can avoid or alleviate shadow effect, and have consistent photoinduction.
According to image sensor structure of the present invention, comprise substrate; Array of sensor elements, it is arranged at substrate surface; Dielectric layer, it covers array of sensor elements, and dielectric layer comprises upper surface, and upper surface comprises recessed dish structure; Bottom, it fills in recessed dish structure, and bottom has refractive index, and its refractive index is greater than the refractive index of dielectric layer; Filter arrays, is arranged on bottom, corresponding array of sensor elements; And microlens array, correspondence is arranged on filter arrays.
In another aspect of this invention, the method according to manufacture image sensor structure of the present invention, comprises the following steps.First, provide substrate; At substrate surface, form array of sensor elements.Then, forming dielectric layer is covered in array of sensor elements and substrate; The upper surface of dielectric layer is formed to recessed dish structure.Then, in recessed dish structure, insert bottom, bottom has refractive index, and it is greater than the refractive index of dielectric layer; On bottom, form filter arrays; On filter arrays, form lenticule (microlens) array.
According to image sensor structure of the present invention, the bottom arranging below filter arrays is filled in the recessed disk shape surface of the dielectric layer below it, and selection primer, make formed bottom except thering is adhesion and providing the function of flat surfaces, still have as the role of convex lens, can the focal length difference between the centerand edge of sensing unit be compensated.Therefore, the photoinduction meeting in same chip is more even.
Accompanying drawing explanation
Fig. 1 shows the generalized section of known CMOS image sensor structure.
Fig. 2 shows the schematic diagram that known CMOS image sensor is combined with camera lens module.
Fig. 3 shows the known method of improving shadow effect.
Fig. 4 shows the generalized section according to the specific embodiment of image sensor structure of the present invention.
Fig. 5 shows the schematic diagram of being combined with camera lens module according to image sensor structure of the present invention.
Fig. 6 shows the generalized section according to another specific embodiment of image sensor structure of the present invention.
Fig. 7 to Figure 10 illustrates the schematic diagram according to each stage of the method for manufacture image sensor structure of the present invention.
Description of reference numerals
10:CMOS image sensor structure 12: light sensitive diode
14: substrate 15: surface
16,18,20: metal conductor layer 22: protective layer
24: dielectric layer 26: bottom
27: top layer 28: colored filter
30: Red lightscreening plate 32: green color filter
34: blue color filter 36: lenticule
38: light 40: camera lens module
42,43,44: lenticule 46: dielectric layer
48: camber line 50: image sensor structure
52: substrate 54: array of sensor elements
55: horizontal surface 56: dielectric layer
58: upper surface 60: bottom
62: filter arrays 64: microlens array
64a, 64b, 64c: lenticule 66: top layer
70: image sensor structure 72: filter
74: lenticule 80: shielding layer
82: Cutting Road
Embodiment
Image sensor structure of the present invention can be applicable to CMOS image sensing element (CIS) or charge coupled cell (CCD).Fig. 4 shows the generalized section according to the specific embodiment of image sensor structure of the present invention.As shown in Figure 4, image sensor structure 50 includes substrate 52, array of sensor elements 54, dielectric layer 56, bottom 60, filter arrays 62 and microlens array 64.Substrate 52 can be for example semiconductor base.Array of sensor elements 54 is arranged at substrate 52 surfaces, is the sensing element of array, can be arranged in substrate surface or go up according to component properties or design, and there is no particular restriction.Sensing element can be for example light sensing element, and light sensing element comprises for example light sensitive diode.Dielectric layer 56 is covered in array of sensor elements 54 and substrate 52.Dielectric layer 56 comprises upper surface 58, and upper surface 58 is toward recessed, and formation scrobicula plate-like or recessed plate-like, are recessed dish structure.In dielectric layer 56, can further be provided with multiple layer metal intraconnections, can be used as the use of conduction or shading.
Primer fills in the formed recessed dish structure of upper surface 58, forms bottom 60.Bottom 60 has refractive index, and this refractive index can be greater than the refractive index of dielectric layer 56, is preferably the refractive index of being a bit larger tham dielectric layer 56, and can further be less than lenticular refractive index.For example refractive index can be approximately between 1.5 to 1.6, but are not limited to this, can determine according to whole optical property.Be used in primer of the present invention, except the requirement of refractive index, preferably there is high light penetration, further there is the function of adhesion coating so that filter and dielectric layer 56 are sticked together, and further there is planarization function to provide planarized surface for filter setting.Moreover, be facility manufacture, be preferably the material that is applicable to inserting technique.Can in known filter bottom or quilting material, pick out, but be not limited to this.The example that can lift has, polymer for example, and it is for example acryl polymer, but is not limited to this.Filter arrays 62 is arranged on bottom 60, and position is corresponding to array of sensor elements 54.Filter arrays 62 can be arranged and be formed by a plurality of filters, and filter can be for example colored filter or achromaticity filter, required and determine according to product.64 correspondences of microlens array are arranged on filter arrays 62.
The recessed dish structure that the upper surface 58 of above-mentioned dielectric layer 56 forms, its recessed degree of depth can be according to optical property and required and determine, because the bottom forming has the character of similar convex lens, therefore, can arrange in pairs or groups such as the size of sensitive zones and the optical property of optical design, bottom, lenticule and filter etc. of image sensor structure, to determine the appropriate degree of depth of recessed dish structure.With digital imaging apparatus generally speaking, aperture numerical value and the recessed dish degree of depth are worked in coordination, so that light all focuses on the same plane of array of sensor elements, can reduce the difference of each sensing unit photoinduction.
Moreover, according to image sensor structure of the present invention, can further comprise shielding layer, it has shaded effect, and shielding layer is arranged in dielectric layer, and around recessed dish structure.Shielding layer can comprise metal material, for example Ti or TiN, hard compared with dielectric layer, therefore when manufacturing according to image sensor structure of the present invention, can utilize this shielding layer and dielectric layer to CMP (chemical mechanic polishing, chemico-mechanical polishing) selection, than different, makes dielectric layer after CMP, have the recessed surface of dish.At sensing unit peripheral part because there is the support of shielding layer, more shallow by the worn degree of depth, at sensing unit core, because be large stretch of dielectric layer center, the recessed effect of dish (dishing effect) of CMP is obvious, easily recessed by mill, so darker by the worn degree of depth.Shielding layer can comprise at least one loop configuration.When shielding layer comprises multi-layer annular structure, its distribution density can peripheral shape (gradient) minimizing in gradient gradually toward center from sensing unit.Or shielding layer can be a plurality of discontinuous section shapes, its distribution density also reduces at Ke Youwaiwang center gradually.
Moreover, can further comprise top layer 66 according to image sensor structure of the present invention, it is arranged on filter and coated filter, and top layer can comprise the material identical with bottom, and can make filter arrays top form flat surfaces.
Fig. 5 shows the schematic diagram of being combined with camera lens module according to image sensor structure of the present invention.As shown in the figure, light 38 is from camera lens module 40 incidents, the light of arrival marginal position focuses to C or C ' point via lenticule 64a or the 64b at edge by top layer 66, filter 62, bottom 60 and dielectric layer 56, the light that arrives centre position focuses to E point via middle lenticule 64c by top layer 66, filter 62, bottom 60 and dielectric layer 56, can find that E point and C or are along the horizontal surface 55 of the substrate 52 at array of sensor elements 54 places at C '.Therefore, for light sensitive diode, under same light quantity is irradiated, different positions can obtain identical photoelectric conversion efficiency, therefore even with the image brilliance that center manifests around at image.
In the present invention, except dielectric layer being formed to recessed dish structure to insert primer to change light refraction path, the method for the known adjusting focal length of can arranging in pairs or groups again.For example Fig. 6 show according to image sensor structure 70 of the present invention, also can be further by part filter 72 toward external migration setting, or by part lenticule 74 toward interior migration setting, that is, make filter be positioned at the arrangement pitch at edge not identical with the pitch that is positioned at center, or it is not identical with the pitch that is positioned at center to make lenticule be positioned at the arrangement pitch at edge.Or, make the microlens shape at microlens array edge and the microlens shape at center not identical.So, further adjusting focal length, and the laminating of reinforcement focal length place plane and sensing element plane.
According to image sensor structure of the present invention, can be made by following method.As shown in Figure 7, first provide substrate 52, then in substrate surface, form array of sensor elements 54, that is, and can be in substrate 52 surfaces or upper formation sensing element.Then, form dielectric layer 56 and cover array of sensor elements 54 and substrate 52.For example utilize chemical vapor deposition method to form this dielectric layer 56.Or, can in dielectric layer 56, further form a plurality of metal levels, for example utilize metal interconnecting technique to reach.Can further deposit the protective layer (passivation layer) being formed by materials such as silicon nitride or silica and be covered in metal level.
Then, the upper surface of dielectric layer 56 58 is formed to recessed dish structure, this can utilize CMP technique grind dielectric layer 56 and reach.For example, when dielectric layer is oxide material, use the CMP technique of grinding oxide.Can for example increase milling time according to required adjustment CMP prescription and condition, can increase recessed degree.Separately can be in dielectric layer 56 around predetermined recessed dish structure part, further form shielding layer 80 structures, when grinding, the reinforcement use of intensity around, slows down grinding rate.Fig. 8 display plane figure, illustrates shielding layer 80 around the situation of array of sensor elements 54, outermost is Cutting Road 82, is cut into independent chip for image sensor structure after completing.Or can be further before carrying out CMP technique, first forming to grind around recessed dish structure part and stop (polishing stop) layer on dielectric layer 56, this dielectric layer that can prevent shielding layer 80 tops is by worn and expose shielding layer 80.If shielding layer 80 is metal materials and exposing, easily element is polluted.
Moreover the upper surface of dielectric layer forms recessed dish structure, can utilize CMP technique and etch process mix and match and complete.In detail, carrying out CMP technique grinding dielectric layer 56, make the upper surface 58 formation dishes of dielectric layer 56 recessed after, can carry out etch process has coiled recessed surface to dielectric layer 56 and has carried out etching, because etch-rate and etching period are easier to control, so can be convenient and control exactly the degree of depth of the formed recessed dish structure of upper surface.
As shown in Figure 9, form after recessed dish structure, in recessed dish structure, insert primer and form bottom 60.For example, use is with monomethyl ether propylene glycol acetic acid esters (PGMEA, propyleneglycolmethyletheracetate) and ethoxyl ethyl propionate (ethyl 3-ethoxypropionate, EEP) as the polymeric material of solvent, utilize method of spin coating to be formed in recessed dish structure, after dry, form bottom 60, there is approximately 95% light penetration.Bottom fills in recessed dish structure and is not limited to and will fills up or not fill up, can actual needs and determine.Bottom 60 in accompanying drawing fills up recessed dish structure, and overflows and cover the initial surface of dielectric layer 56.
Then, as shown in figure 10, on bottom 60, form filter arrays 62.Can further on filter arrays 62, form top layer 66, its material can be identical with bottom 60, also can utilize the method for coating to form.Then, on filter arrays 62, form microlens array 64, make each filter correspond respectively to lenticule, and corresponding to sensing unit.
Due to, in the method for the invention, compared to known method, feature is to carry out CMP grinding to form recessed dish structure, and inserts primer in recessed dish structure, forms bottom, bottom has the function of adjusting focal length, planarization and adhesion filter simultaneously, serves multiple.Primer can be selected (but being not limited to this) in becoming known for the bottom of filter and the material of top layer, moreover, while being known in dielectric layer formation, also need through planarization, and in the present invention, therefore just can utilize the technique of its cmp planarization to obtain desired recessed dish structure, in technique, can't increase loaded down with trivial details step or spend more the material of expense, quite convenient.
The foregoing is only the preferred embodiments of the present invention, all equivalent variations of doing according to the claims in the present invention and modification, all should belong to covering scope of the present invention.
Claims (14)
1. an image sensor structure, comprising:
Substrate;
Array of sensor elements, it is arranged at this substrate surface;
Dielectric layer, it covers this array of sensor elements, and this dielectric layer comprises upper surface, and this upper surface comprises recessed dish structure;
Bottom, it fills in this recessed dish structure, and this bottom has refractive index, and this refractive index is greater than the refractive index of this dielectric layer;
Filter arrays, is arranged on this bottom, to should array of sensor elements; And
Microlens array, correspondence is arranged on this filter arrays,
Wherein to be positioned at the pitch at edge not identical with the pitch that is positioned at center for those lenticules.
2. image sensor structure as claimed in claim 1, wherein this array of sensor elements is light sensing unit array.
3. image sensor structure as claimed in claim 1, wherein the refractive index of this bottom is 1.5 to 1.6.
4. image sensor structure as claimed in claim 1, wherein the refractive index of this bottom is less than those lenticular refractive indexes.
5. image sensor structure as claimed in claim 1, wherein this bottom is adhesion coating, and its top flat.
6. image sensor structure as claimed in claim 1, further comprises shielding layer, and it is arranged in this dielectric layer, and around this recessed dish structure.
7. image sensor structure as claimed in claim 6, wherein this shielding layer comprises metal material.
8. image sensor structure as claimed in claim 6, wherein this shielding layer comprises at least one loop configuration.
9. image sensor structure as claimed in claim 8, wherein this shielding layer comprises multi-layer annular structure, and reduce gradually at the distribution density You Waiwang center of this shielding layer.
10. image sensor structure as claimed in claim 6, wherein this shielding layer comprises a plurality of sections.
11. image sensor structures as claimed in claim 10, wherein reduce gradually at the distribution density You Waiwang center of this shielding layer.
12. image sensor structures as claimed in claim 1, to be wherein positioned at the shape at edge not identical with the shape that is positioned at center for those lenticules.
13. image sensor structures as claimed in claim 1, to be wherein positioned at the pitch at edge not identical with the pitch that is positioned at center for those filters.
14. image sensor structures as claimed in claim 1, further comprise top layer, and it is arranged on those filters and coated those filters, and comprises the material identical with this bottom.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910174746.3A CN102024829B (en) | 2009-09-17 | 2009-09-17 | Image sensor structure and manufacture method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910174746.3A CN102024829B (en) | 2009-09-17 | 2009-09-17 | Image sensor structure and manufacture method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102024829A CN102024829A (en) | 2011-04-20 |
| CN102024829B true CN102024829B (en) | 2014-03-26 |
Family
ID=43865926
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200910174746.3A Active CN102024829B (en) | 2009-09-17 | 2009-09-17 | Image sensor structure and manufacture method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102024829B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9030744B2 (en) * | 2011-09-19 | 2015-05-12 | Infineon Technologies Ag | Fabrication of micro lenses |
| CN104917937B (en) * | 2014-03-10 | 2018-10-26 | 奇景光电股份有限公司 | Image-pickup assembly and its lens unit array |
| US9691810B1 (en) * | 2015-12-18 | 2017-06-27 | Omnivision Technologies, Inc. | Curved image sensor |
| US10418408B1 (en) * | 2018-06-22 | 2019-09-17 | Omnivision Technologies, Inc. | Curved image sensor using thermal plastic substrate material |
| CN110162228B (en) * | 2019-05-09 | 2024-02-02 | 惠州市航泰光电有限公司 | Capacitive touch display screen for face brushing payment and production and manufacturing method thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1472818A (en) * | 2002-08-01 | 2004-02-04 | 台湾积体电路制造股份有限公司 | Image sensor microlens set, image sensor and producing method thereof |
| CN1518118A (en) * | 2003-01-17 | 2004-08-04 | 夏普株式会社 | Process for manufacturing semiconductor device and semiconductor device |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6590239B2 (en) * | 2001-07-30 | 2003-07-08 | Taiwan Semiconductor Manufacturing Co., Ltd. | Color filter image array optoelectronic microelectronic fabrication with a planarizing layer formed upon a concave surfaced color filter region |
| US7122840B2 (en) * | 2004-06-17 | 2006-10-17 | Taiwan Semiconductor Manufacturing Co., Ltd. | Image sensor with optical guard ring and fabrication method thereof |
| US20080191299A1 (en) * | 2007-02-12 | 2008-08-14 | Christopher Parks | Microlenses for irregular pixels |
-
2009
- 2009-09-17 CN CN200910174746.3A patent/CN102024829B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1472818A (en) * | 2002-08-01 | 2004-02-04 | 台湾积体电路制造股份有限公司 | Image sensor microlens set, image sensor and producing method thereof |
| CN1518118A (en) * | 2003-01-17 | 2004-08-04 | 夏普株式会社 | Process for manufacturing semiconductor device and semiconductor device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102024829A (en) | 2011-04-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7007309B2 (en) | Plenoptic sensor | |
| US8314469B2 (en) | Image sensor structure with different pitches or shapes of microlenses | |
| CN100365820C (en) | Solid-state image sensor, manufacturing method for solid-state image sensor, and camera | |
| US7580204B2 (en) | Method for manufacturing lenses, in particular for an imager comprising a diaphragm | |
| CN100504505C (en) | Lens array and method of making same | |
| CN102024829B (en) | Image sensor structure and manufacture method thereof | |
| JP5269454B2 (en) | Solid-state image sensor | |
| US8329498B2 (en) | Method of manufacturing a semiconductor wafer comprising an integrated optical filter | |
| CN104485339A (en) | Solid-state imaging device, electronic apparatus, and method for manufacturing solid-state imaging device | |
| US20070145437A1 (en) | Image sensor and method of manufacturing the same | |
| CN105321965A (en) | Image Sensing Device and Method for Fabricating the Same | |
| US9293488B2 (en) | Image sensing device | |
| KR100720461B1 (en) | Image sensor and method of manufacturing the same | |
| US8937774B2 (en) | Method for making paired lenses with an opaque barrier between, and product made | |
| CN101359673B (en) | Image sensor | |
| US20100289101A1 (en) | Image sensor | |
| US8149322B2 (en) | Image sensor with an improved sensitivity | |
| CN103137639A (en) | Backside-illuminated (BSI) pixel including light guide | |
| US7964432B2 (en) | Method of manufacturing lenses, in particular for an integrated imager | |
| CN100477244C (en) | Image sensor and method for fabricating the same | |
| US20060278906A1 (en) | Image sensor | |
| CN211700289U (en) | Micro-lens component, biological identification module and electronic equipment | |
| TWI497700B (en) | Image sensor structure and fabricating method therefor | |
| TW202412292A (en) | Half quad photodiode (qpd) to improve qpd channel imbalance | |
| US20120146169A1 (en) | Method for manufacturing solid state imaging device and solid state imaging device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |