CN1804724A - Oil-immersed exposure method for chip photolithography process - Google Patents
Oil-immersed exposure method for chip photolithography process Download PDFInfo
- Publication number
- CN1804724A CN1804724A CN 200510002157 CN200510002157A CN1804724A CN 1804724 A CN1804724 A CN 1804724A CN 200510002157 CN200510002157 CN 200510002157 CN 200510002157 A CN200510002157 A CN 200510002157A CN 1804724 A CN1804724 A CN 1804724A
- Authority
- CN
- China
- Prior art keywords
- chip
- oil
- exposure
- medium
- exposure method
- 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.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/70216—Mask projection systems
- G03F7/70341—Details of immersion lithography aspects, e.g. exposure media or control of immersion liquid supply
Abstract
The invention relates to an optical etching process method of chip, especially to an oil-immersed exposure method during chip etching course. It comprises the following steps: 1) fist positioning a light shield lens system of the etching machine to the exposure media; 2) coating exposure media on the chip before the aiming and exposure processes in the exposure reaction room; 3) laying out the chip surface exposure media so that it is even without bubble; 4) moving the light shield on the chip, adjusting the low lens system so that the lens mirror can touch the chip surface exposure media. The exposure media is a vegetable oil, especially to cedar oil.
Description
Technical field
The optics that the present invention relates to chip is scribed job operation, refers in particular to the exposure method in the chip lithographic process.
Background technology
Chip belongs to the microelectronics technology in the high-tech, is mainly used in computing machine, communication, military project and space flight and manufacturing industry etc., and along with the development of society also extensively enters the every field that closely links to each other with people's daily life.And along with the widespread use of chip technology has promoted himself develop rapidly more, be that the performance and the functions of use of chip enlarges day by day on the one hand, the external appearance characteristic size of chip is then more and more littler, to such an extent as to make chip progressively enter small or the ultra micro state.No matter how small the chip feature size is, must primarily guarantee to be printed on the degree of accuracy of on-chip circuitry figure and enough resolution.For this reason, the processing of the photolithographic fabrication of chip then is gordian technique wherein.For example, the update of integrated circuit depends on the development of photoetching technique, all will research and develop the specific photoetching technique of a new generation to each for integrated circuit technique.The photoetching method of Cai Yonging---is the method for beam propagation medium with the air---will meet with bottleneck below being reduced to 100 nanometers along with characteristic dimension for a long time.It is generally acknowledged, utilize optical lithography method to print Micropicture near the limit.Optical lithography method develops into the scanning projection formula from contact proximity, reflective projection formula, stepping projection at present.Other new technologies that may replace optical lithography method are developed, such as: projection electron lithography technology (EPL), ion projection's photoetching technique (IPL), X-X-ray lithography X technology, e-beam direct write lithography technology (EBDW) and extreme ultraviolet photoetching technique (EUV).In traditional chip photoetching method, chip promptly enters the chip manufacture fabrication phase after finishing design.Its technology is summarized as follows: (1) makes light shield, and the general using electron beam duplicates performance outward appearance level (Layout) design of chip on the light shield, comprises the manufacturing of photoetching mother matrix and mask; (2) prepare wafer, wafer is the base stock of chip manufacturing; (3) oxidation utilizes special gas, makes the chip crystal issue biochemical reaction at specified temp, produces oxide layer, silicon nitride layer and polysilicon layer respectively; (4) develop, coat photoresistance liquid, utilize light shield that each layer exposed then, form protective seam, the i.e. zone that will keep at each layer of previous step; (5) etching utilizes chemical substance (strong acid, highly basic) that etching is carried out in unexposed non-protection area territory, thereby produces needed structure outward appearance; (6) ion is implanted, and implanting ions makes the specific region ionization; (7) metal sputtering makes wafer surface cover the layer of metal material, utilizes photoresistance liquid and following one deck light shield to make metallic circuit again, so that transistorized connection; (8) make one deck down, repeating step (3) is successively finished the structure of chip to (8); (9) test.
Make the complete fundamental technology of chip, five lithographic process are generally arranged, each lithographic process all has exposure, etched program, and in fact relating to therebetween and making the meticulousr key of little printing is the method which type of medium light beam passes through and use this medium.
Stamp in the chip manufacturing is the light sensitive material thin layer (being called photoresist, photoresistance liquid) at semiconductor wafer surface, stamps casting mold how much, and the figure on the different mask is stamped more than once on crystal layer, to form the element pattern; Obtain each zones of different through etching again, so that implant, spread.The photoresistance compound is divided into positive glue and negative glue to radiation tool susceptibility.Behind the photoresist,, by developer solution the positive peptization of exposure region is separated, cleans, dried again on the wafer, remove the insulation course of exposure region again through etching, and the photoresist of unexposed area is not subjected to etching, removes photoresist at last through exposure-processed.Promptly can be made into the insulation course casting mold image of design through this program.The processing procedure of entire circuit system must repeatedly be made repeatedly aforesaid stamp and etching program at crystal column surface usually.
Chip feature dimension of picture, alignment tolerant degree, crystal column surface situation and the photoetching number of plies all can have influence on the complexity of specific light carving technology and the technology of each step.In different chip factories, many photoetching processes all are customized to specific process conditions, and various concrete technologies all are the variation or the options of basic photoetching 10 footworks.10 footworks of lithographic process following (technological process with bright field mask and negative glue is an example): 1, prepare on the surface, cleaning and dry crystal column surface; 2, resist coating is evenly smeared the skim photoresist at crystal column surface; 3, soft baking, heating, part is evaporated photoresist solvent; 4, aim at and exposure, mask and figure on wafer accurate aligning and the exposure of photoresist, negative glue is polymkeric substance; 5, develop the removal of non-polymeric photoresist; 6, cure firmly, to the continuation evaporation of solvent; 7, surperficial alignment case and defect situation are checked in the development visual inspection; 8, etching is removed the wafer top layer by the opening of photoresist; 9, photoresist is removed, and the photoresist layer on the wafer is removed; 10, final visual inspection.For guaranteeing that figure on the lithography mask version projects the degree of accuracy of the minimum and dimension of picture the best of the loss of the resolution on the wafer surface, how the loss and the dimension of picture of control resolution then are the keys of technology.If can find new exposure method to dwindle the circuit size on the chip, will improve constantly chip performance.Yet, do not find as yet at present and a kind ofly both afforded high research and development expense and can make microelectronic circuit be reduced to more small method.
In the experiment that biology microscope is observed, the conversion of the light path medium of observation is expanded the medium thinking for the chip manufacturing field new thinking is provided.As, be in the normal observation of light propagation medium with the air, micro-multiple is 20～640 times;---promptly adopting oil immersion objective---micro-multiple can reach 500～1600 times and be in the observation of light propagation medium with oil.
The patent of invention content
The objective of the invention is, oil immersed type exposure method in a kind of lithographic process that can significantly improve chip integration is provided.For realizing this method, adopt following technical scheme: improved exposure method in a kind of chip lithography process, (1) are at first inserted exposure medium in the light shield lens combination of litho machine; (2) in the exposure reaction chamber, chip adds and is coated with exposure medium before " aim at and exposure " operation; (3) exposure medium on the open and flat chip surface makes its uniformity and bubble must not occur; (4) light shield is moved on the chip, fine setting decline lens combination makes lenses touch exposure medium on the chip; Exposure medium is a kind of grease, and grease is a vegetable oil, and grease is a synthetic oil; The preferred cedar oil of vegetable oil; The open and flat thickness of cedar oil is 1～2mm, and the open and flat thickness of preferred cedar oil is 1.5mm.
As previously mentioned, " exposure " in the lithographic process is the committed step that improves chip integration, known from the principle of photolithographic exposure projection, the refractive index n of the light beam medium of " aiming at and exposure " in the photoetching process, the various performances of light shield and lens thereof have partly been determined, as degree of accuracy of miniature resolution, the depth of focus, light beam etc.Improve the refractive index n of light beam medium, just can improve the performance of light shield and lens thereof and the effect of exposure, improve miniature multiple and degree of accuracy.Minimum dimension on the wafer, the minimum resolution distance of lens in other words is that the physical attribute by projection optical system is limited.According to optic auspicious thunder criterion, relational expression is arranged:
σ＝κλ/N.A.＝0.61λ/(n·sin?θ)
In the formula: σ is minimum dimension of picture, κ is auspicious thunder constant, λ is the wavelength of exposure light source, n be wafer place medium (promptly, the medium of beam propagation) refractive index, θ contracts as the subtended angle of lens radius to wafer, and nsin θ is the numerical aperture (numberical aperture is abbreviated as N.A.) of lens.Numerical aperture nsin θ is big more, and then σ is more little, and the resolving power of lens is just high more.Known, the clean cost of the air of refractive index n=1 is huge, and its miniature limit is near; The vacuum of refractive index n=1 exposure in the reaction chamber generation and discharge and not only invest high and efficient is low; And the water of refractive index n=1.33, because to the chemical factors such as influence of water-soluble photoresistance liquid, its application as the light beam medium is had a problematic future; The solid that refractive index is high is inapplicable because of the damage that the contact wafer causes.Only refractive index may be the object of selecting near the grease of glass and photoresist, for example, and crude vegetal, natural animal oil, mineral oil and synthetic oil.By the experiment that biology microscope is observed and the technical relation of method of photolithographic exposure, select the medium that various light are propagated---particularly refractive index is near glass, chemical characteristic is inactive, physical characteristics is stable, composition is single crude vegetal, propose to adopt the empty G﹠W of refractive index ratio all high, not only near photoresist (refractive index n=1.45) but also near cedar oil (the cedar oil of glass (refractive index n=1.40～2.00), claim san-mou oil again), as exposure medium in the photoetching technique.Cedar oil is a yellow liquid, and density is about 0.92, refractive index n=1.515～1.52, and the solidifying point of grease and fatty acid is low, is the optimal selection of light beam medium in the photoetching technique.For this reason, if lens are immersed in the oil, the value of its 0.61/ (nsin θ) may diminish to 0.5, and the minimum dimension of picture that promptly can differentiate is about half of exposure wavelength.Fill with medium oil in lens combination, mask plate is immersed in the medium oil, after light beam penetrates from condensing lens system, through medium oil, see through the glass of mask plate, pass through medium oil again, see through the picture lens combination that contracts again, pass through medium oil then, finally arrive photoresist; The refractive index of section light path of this from the collector lens to the photoresist is consistent substantially, so also can guarantee the degree of accuracy of light beam and miniature resolution.Adopting the present invention is the exposure method of medium with oil, can produce the figure also littler than exposure wavelength.If as lens radius the subtended angle θ of wafer is done improvement from contracting again, use method of the present invention, theoretic minimum dimension of picture can also further dwindle.If use the present invention on the wavelength of 193 nanometers, the research and development of chip and production just can enter 60 nano-scale linewidths from generation to generation.The lithographic equipment lens combination (comprises condensing lens system, contracts as lens combination, the front and back difference of concrete miniature multiple and the new immersion lens of changing), can provide a reference according to the experimental result that biology microscope is observed, if other conditions are constant, conversion oil immersion objective (optical multiplier 100X) and be exposure medium with oil, can make micro-multiple is that the observation of medium (on object lens optical multiplier 4～40X) bases, improves 2.5～25 times at air.
Description of drawings
Fig. 1 is the exposure system synoptic diagram of an embodiment of the present invention;
Fig. 2 is the exposure system synoptic diagram of the another kind of embodiment of the present invention.
Embodiment
Just embodiment is further described in detail in conjunction with the accompanying drawings.Before chip 1 was implemented exposure process, undertaken by following step: (1) at first inserted cedar oil 30 in the light shield lens combination 2 of litho machine; (2) in the exposure reaction chamber, before " aim at and exposure " operation, add and be coated with cedar oil 31 in chip 1; (3) open and flat chip 1 lip-deep cedar oil 31 makes cedar oil thickness be 1.5mm (can also be respectively 1mm, 2mm) bubble must not to occur; (4) light shield 2 is moved on the chip 1, fine setting decline lens combination, making contracts touches cedar oil 31 on the chip 1 as lenses 20, form the light path of beam propagation after, can carry out " aiming at and exposure " and later operations such as cleaning, development and etching by former technological requirement.
Among the embodiment shown in Figure 2, light shield lens combination 2 is not inserted cedar oil, only on chip 1, add and be coated with cedar oil 31 (thickness of cedar oil can be respectively 1mm and 2mm), make contracting of lens combination touch cedar oil 31 as lens 20, light beam penetrates from the picture lens combination that contracts like this, through medium oil 31, arrive chip 1 and implement exposure with preface." S " shown in the figure is that light source, " H " are that mask plate (white portion is that glass film plates, black region are chromium coating), 10 is that wafer, 11 is that oxide layer, 12 is photoresist for the thickness of medium oil, 21.
Claims (7)
1, oil immersed type exposure method in a kind of chip lithographic process, it is characterized in that comprising following step: (1) at first inserts exposure medium in the light shield lens combination of litho machine; (2) in the exposure reaction chamber, chip adds and is coated with exposure medium before " aim at and exposure " operation; (3) exposure medium on the open and flat chip surface makes its uniformity and bubble must not occur; (4) light shield is moved on the chip, fine setting decline lens combination makes lenses touch exposure medium on the chip.
2, by oil immersed type exposure method in the described chip lithographic process of claim 1, it is characterized in that exposure medium is a kind of grease.
3, by oil immersed type exposure method in the described chip lithographic process of claim 2, it is characterized in that grease is a vegetable oil.
4, by oil immersed type exposure method in the described chip lithographic process of claim 2, it is characterized in that grease is a synthetic oil.
5, by oil immersed type exposure method in claim 2 or the 3 described chip lithographic process, it is characterized in that the preferred cedar oil of vegetable oil.
6, by oil immersed type exposure method in the described chip lithographic process of claim 5, the open and flat thickness that it is characterized in that cedar oil is 1～2mm.
7, by oil immersed type exposure method in the described chip lithographic process of claim 6, the open and flat thickness that it is characterized in that preferred cedar oil is 1.5mm.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510002157 CN1804724A (en) | 2005-01-14 | 2005-01-14 | Oil-immersed exposure method for chip photolithography process |
| PCT/CN2005/000121 WO2006074579A1 (en) | 2005-01-14 | 2005-01-28 | Oil immersion exposure method in chip photolithographic process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510002157 CN1804724A (en) | 2005-01-14 | 2005-01-14 | Oil-immersed exposure method for chip photolithography process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1804724A true CN1804724A (en) | 2006-07-19 |
Family
ID=36677343
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200510002157 Pending CN1804724A (en) | 2005-01-14 | 2005-01-14 | Oil-immersed exposure method for chip photolithography process |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN1804724A (en) |
| WO (1) | WO2006074579A1 (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2474708B1 (en) * | 1980-01-24 | 1987-02-20 | Dme | HIGH-RESOLUTION MICROPHOTOLITHOGRAPHY PROCESS |
| US5121256A (en) * | 1991-03-14 | 1992-06-09 | The Board Of Trustees Of The Leland Stanford Junior University | Lithography system employing a solid immersion lens |
| JP2753930B2 (en) * | 1992-11-27 | 1998-05-20 | キヤノン株式会社 | Immersion type projection exposure equipment |
| JP3747566B2 (en) * | 1997-04-23 | 2006-02-22 | 株式会社ニコン | Immersion exposure equipment |
| JP3817836B2 (en) * | 1997-06-10 | 2006-09-06 | 株式会社ニコン | EXPOSURE APPARATUS, ITS MANUFACTURING METHOD, EXPOSURE METHOD, AND DEVICE MANUFACTURING METHOD |
| US5900354A (en) * | 1997-07-03 | 1999-05-04 | Batchelder; John Samuel | Method for optical inspection and lithography |
| SG131766A1 (en) * | 2002-11-18 | 2007-05-28 | Asml Netherlands Bv | Lithographic apparatus and device manufacturing method |
-
2005
- 2005-01-14 CN CN 200510002157 patent/CN1804724A/en active Pending
- 2005-01-28 WO PCT/CN2005/000121 patent/WO2006074579A1/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| WO2006074579A1 (en) | 2006-07-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7305651B2 (en) | Mask CD correction based on global pattern density | |
| US7971160B2 (en) | Creating method of photomask pattern data, photomask created by using the photomask pattern data, and manufacturing method of semiconductor apparatus using the photomask | |
| US6251549B1 (en) | Generic phase shift mask | |
| TW200908089A (en) | Writing method and charged particle beam writing apparatus | |
| TW200525178A (en) | A method, program product and apparatus of simultaneous optimization for NA-sigma exposure settings and scattering bars OPC using a device layout | |
| US7001696B2 (en) | Near-field light exposure mask with avoidance of overlap of near-field light, method for manufacturing the same, exposure apparatus and method using near-field light exposure mask, and method for manufacturing device | |
| US20040048166A1 (en) | Contact printing as second exposure of double exposure attenuated phase shift mask process | |
| US20110229805A1 (en) | Photomask with assist features | |
| US6828080B2 (en) | Pattern forming method and method of fabricating device | |
| CN102236247A (en) | Preparation method of photomask | |
| US8563227B2 (en) | Method and system for exposure of a phase shift mask | |
| CN113406859A (en) | Modeling method of optical proximity correction model | |
| JP2000066366A (en) | Photomask and its production | |
| US9046783B2 (en) | Photomask, and pattern formation method and exposure apparatus using the photomask | |
| JP2005129648A (en) | Method of forming contact hole | |
| US20070148558A1 (en) | Double metal collimated photo masks, diffraction gratings, optics system, and method related thereto | |
| CN101133365B (en) | Exposure method, method for forming irregular pattern, and method for manufacturing optical element | |
| US20090311615A1 (en) | Method of photolithographic patterning | |
| JP5644290B2 (en) | Photomask manufacturing method | |
| CN114460819B (en) | Alignment mark for electron beam exposure and preparation method thereof | |
| US7669173B2 (en) | Semiconductor mask and method of making same | |
| CN1804724A (en) | Oil-immersed exposure method for chip photolithography process | |
| US20150309414A1 (en) | Method and tool of lithography | |
| TWI225574B (en) | Photomask structure and method of reducing lens aberration and pattern displacement | |
| CN106919015B (en) | A kind of semiconductor devices making lithography alignment method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |