阅读说明：本技术 光刻胶及光刻方法 (Photoresist and photolithography method ) 是由 袁华 黄永发 杨尚勇 胡展源 于 2019-08-13 设计创作，主要内容包括：本申请公开了一种光刻胶和光刻方法,属于半导体制造技术领域。所述光刻胶包括：化学放大胶,该化学放大胶包括聚合树脂和光致产酸剂；碱性添加剂,在被光照后,该碱性添加剂的酸碱度由碱性转变至酸性。本申请通过在包含光学放大胶的光刻胶中添加碱性添加剂,在将该光刻胶应用于光刻工艺时,光刻胶中的光致消碱剂在曝光区域碱性消失,不影响光酸化学放大,保留非曝光区域的碱性,淬灭非曝光区域产生的微量酸分子,使得曝光区域和非曝光区域酸分子浓度差异增大,提高了曝光区域与非曝光区域的对比度,从而能够优化光刻图形的形貌,增大光刻的工艺窗口。(This application discloses a kind of photoresist and photolithography methods, belong to technical field of manufacturing semiconductors.The photoresist includes: chemically amplified resists, which includes polymer resin and photo-acid generator；Alkalinity additive, after by illumination, the pH value of the alkalinity additive is converted to acidity by alkalinity.The application is by adding alkalinity additive in the photoresist comprising optical amplifier glue, when the photoresist is applied to photoetching process, the photic alkaline agent that disappears in photoresist disappears in exposure area alkalinity, light acidification is not influenced learns amplification, retain the alkalinity of non-exposed areas, the micro acid molecule of non-exposed areas generation is quenched, so that exposure area and non-exposed areas acid molecule concentration difference increase, improve the contrast of exposure area and non-exposed areas, so as to optimize the pattern of litho pattern, increase the process window of photoetching.)

1. a kind of photoresist, which is characterized in that the photoresist is applied in the photoetching process for preparing semiconductor devices, the light Photoresist includes:

Chemically amplified resists, the chemically amplified resists include polymer resin and photo-acid generator；

Alkalinity additive, after by illumination, the pH value of the alkalinity additive is converted to acidity by alkalinity.

2. photoresist according to claim 1, which is characterized in that the alkalinity additive, which includes that sulfanilic acid esters are photic, to disappear Alkaline agent.

3. photoresist according to claim 2, which is characterized in that the chemical general formula of the photic alkaline agent that disappears of sulfanilic acid esters For NR₂-X-NR-O-SO₂-C_nF_2n+1；

Wherein, R indicates that saturated alkane group or hydrogen, X indicate big conjugation extinction group, and n is positive integer.

4. photoresist according to claim 3, which is characterized in that include 1 to 4 carbon original when R is saturated alkane group Son.

5. photoresist according to claim 3, which is characterized in that 1≤n≤8.

6. photoresist according to any one of claims 1 to 5, which is characterized in that the alkalinity additive polymerize tree with described The mass values of rouge are 0.01%-5%.

7. a kind of photolithography method, which is characterized in that the described method includes:

The coating photoresist on object, the photoresist include chemically amplified resists and alkalinity additive, the chemically amplified resists Including polymer resin and photo-acid generator, the alkalinity additive is after by illumination, and the pH value of the alkalinity additive is by alkali Sex reversal is to acidity；

The photoresist is divided into exposure area and non-exposed areas by mask plate, the exposure area is exposed, institute The alkalinity additive stated in exposure area is changed into acidity by alkalinity, and the alkalinity additive in the non-exposed areas passes through reservation Alkalinity be quenched in the exposure area diffuse through come acid；

Development treatment is carried out to the photoresist, removes the photoresist of the exposure area.

8. photolithography method according to claim 7, which is characterized in that the alkalinity additive includes that sulfanilic acid esters are photic Disappear alkaline agent.

9. photolithography method according to claim 8, which is characterized in that the chemistry of the photic alkaline agent that disappears of sulfanilic acid esters is logical Formula is NR₂-X-NR-O-SO₂-C_nF_2n+1；

Wherein, R indicates that saturated alkane group or hydrogen, X indicate big conjugation extinction group, and n is positive integer.

10. photolithography method according to claim 9, which is characterized in that include 1 to 4 carbon when R is saturated alkane group Atom.

11. photolithography method according to claim 9, which is characterized in that 1≤n≤8.

12. according to any photolithography method of claim 7 to 11, which is characterized in that the alkalinity additive gathers with described The mass values of resin are 0.01%-5%.

Technical field

This application involves technical field of manufacturing semiconductors, and in particular to a kind of photoresist and photolithography method.

Background technique

Summary of the invention

The embodiment of the present application provides a kind of photoresist and photolithography method, can solve the photoresist provided in the related technology Lead to the problem that lithographic process window is lower.

On the one hand, the embodiment of the present application provides a kind of photoresist, and the photoresist is applied to prepare semiconductor devices In photoetching process, the photoresist includes:

Chemically amplified resists, the chemically amplified resists include polymer resin and photo-acid generator；

Alkalinity additive, after by illumination, the pH value of the alkalinity additive is converted to acidity by alkalinity.

In an alternative embodiment, the alkalinity additive includes the photic alkaline agent that disappears of sulfanilic acid esters.

In an alternative embodiment, the chemical general formula of the photic alkaline agent that disappears of the sulfanilic acid esters is NR₂-X-NR-O- SO₂-C_nF_2n+1；

Wherein, R indicates that saturated alkane group or hydrogen, X indicate big conjugation extinction group, and n is positive integer.

It in an alternative embodiment, include 1 to 4 carbon atom when R is saturated alkane group.

In an alternative embodiment, 1≤n≤8.

In an alternative embodiment, the mass values of the alkalinity additive and the polymer resin are 0.01%- 5%.

On the one hand, the embodiment of the present application provides a kind of photolithography method, which comprises

The coating photoresist on object, the photoresist include chemically amplified resists and alkalinity additive, and the chemistry is put Big glue includes polymer resin and photo-acid generator, and the alkalinity additive is after by illumination, the pH value of the alkalinity additive Acidity is converted to by alkalinity；

The photoresist is divided into exposure area and non-exposed areas by mask plate, the exposure area is exposed Light, the alkalinity additive in the exposure area are changed into acidity by alkalinity, and the alkalinity additive in the non-exposed areas is logical The alkalinity for crossing reservation, which is quenched in the exposure area, diffuses through the acid come；

Development treatment is carried out to the photoresist, removes the photoresist of the exposure area.

In an alternative embodiment, the alkalinity additive includes the photic alkaline agent that disappears of sulfanilic acid esters.

In an alternative embodiment, the chemical general formula of the photic alkaline agent that disappears of the sulfanilic acid esters is NR₂-X-NR-O- SO₂-C_nF_2n+1；

Wherein, R indicates that saturated alkane group or hydrogen, X indicate big conjugation extinction group, and n is positive integer.

It in an alternative embodiment, include 0 to 4 carbon atom in R.

In an alternative embodiment, 1≤n≤8.

In an alternative embodiment, the mass values of the alkalinity additive and the polymer resin are 0.01%- 5%.

Technical scheme includes at least following advantage:

By adding alkalinity additive in the photoresist comprising optical amplifier glue, which is being applied to photoetching work When skill, the photic alkaline agent that disappears in photoresist disappears in exposure area alkalinity, does not influence light acidification and learns amplification, retains non-exposed areas Alkalinity, be quenched non-exposed areas generation micro acid molecule so that exposure area and non-exposed areas acid molecule concentration difference Increase, improves the contrast of exposure area and non-exposed areas, so as to optimize the pattern of litho pattern, increase photoetching Process window.

Detailed description of the invention

It, below will be to specific in order to illustrate more clearly of the application specific embodiment or technical solution in the prior art Embodiment or attached drawing needed to be used in the description of the prior art be briefly described, it should be apparent that, it is described below Attached drawing is some embodiments of the application, for those of ordinary skill in the art, before not making the creative labor It puts, is also possible to obtain other drawings based on these drawings.

Fig. 1 is the flow chart for the photolithography method that one exemplary embodiment of the application provides；

Fig. 2 to Fig. 5 is the schematic diagram that acid diffuses to non-exposed areas.

Specific embodiment

Below in conjunction with attached drawing, clear, complete description is carried out to the technical solution in the present invention, it is clear that described Embodiment is a part of the embodiments of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, this field is general Logical technical staff's all other embodiment obtained under the premise of not making creative work belongs to what the present invention protected Range.

In the description of the present application, it should be noted that term " center ", "upper", "lower", "left", "right", "vertical", The orientation or positional relationship of the instructions such as "horizontal", "inner", "outside" be based on the orientation or positional relationship shown in the drawings, merely to Convenient for describe the application and simplify description, rather than the device or element of indication or suggestion meaning must have a particular orientation, It is constructed and operated in a specific orientation, therefore should not be understood as the limitation to the application.In addition, term " first ", " second ", " third " is used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance.

In the description of the present application, it should be noted that unless otherwise clearly defined and limited, term " installation ", " phase Even ", " connection " shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or be integrally connected；It can To be mechanical connection, it is also possible to be electrically connected；It can be directly connected, can also may be used also indirectly connected through an intermediary To be the connection inside two elements, it can be wireless connection, be also possible to wired connection.For the ordinary skill people of this field For member, the concrete meaning of above-mentioned term in this application can be understood with concrete condition.

As long as in addition, the non-structure each other of technical characteristic involved in the application different embodiments disclosed below It can be combined with each other at conflict.

Chemically amplified resists mainly include the components such as fluoropolymer resin, photo-acid generator, dyestuff and solvent.Its principle be Under conditions of exposure it is photic produce acid, fluoropolymer resin acid-unstable group be detached under the action of an acid, occur polarity reversion, simultaneously An acid molecule is discharged, realization acid amplification during (Post Exposure Bake, PEB) is toasted after exposure, ultimately generates Dissolve in the product of alkaline-based developer.

It has been found that due in exposure and during PEB excessive acid diffusion and light in mask plate, photoresist, base It the problems such as diffraction that occurs between bottom, scattering, reflection, causes non-exposed areas to have faint exposure phenomenon, causes graphic edge thick Rough, structure is not steep, and with design size deviate the problems such as, increase generate defect a possibility that, reduce the work of photoetching Skill window.

In view of the above-mentioned problems, the embodiment of the present application provides a kind of photoresist, which is applied to prepare semiconductor device In the photoetching process of part, which includes chemically amplified resists and alkalinity additive.

Wherein, chemically amplified resists include polymer resin and photo-acid generator；Alkalinity additive is after by illumination, pH value Acidity is converted to by alkalinity, specifically, after by illumination, the alkalinity of alkalinity additive disappears alkalinity additive, is rendered as Property, then it is changed into acidity；The mass values of alkalinity additive and polymer resin are 0.01%-5%.

Optionally, which includes the photic alkaline agent that disappears of sulfanilic acid esters；The photic alkaline agent that disappears of the sulfanilic acid esters Chemical general formula is NR₂-X-NR-O-SO₂-C_nF_2n+1.Wherein, R indicates that saturated alkane group or hydrogen, X indicate big conjugation extinction base Group, n is positive integer.Wherein, saturated alkane group includes 1 to 4 carbon atom；C_nF_2n+1Including 1 to 8 carbon atom, that is, 1≤n ≤8。

In conclusion in the embodiment of the present application, by adding alkalinity additive in the photoresist comprising optical amplifier glue, When the photoresist is applied to photoetching process, the photic alkaline agent that disappears in photoresist disappears in exposure area alkalinity, does not influence light Acidification learn amplification, retain the alkalinity of non-exposed areas, be quenched non-exposed areas generation micro acid molecule so that exposure area and Non-exposed areas acid molecule concentration difference increases, and the contrast of exposure area and non-exposed areas is improved, so as to optimize The pattern of litho pattern increases the process window of photoetching.

Fig. 1 shows the flow chart of the photolithography method of one exemplary embodiment of the application offer.This method comprises:

Step 101, the coating photoresist on object, the photoresist include chemically amplified resists and alkalinity additive, the change Learning amplification glue includes polymer resin and photo-acid generator.

Illustratively, object can be the substrate of semiconductor devices, be also possible to the oxide deposited on substrate or Nitride is also possible to metal deposited on substrate etc..The photoresist is the photoresist in above-described embodiment.

Step 102, photoresist is divided by exposure area and non-exposed areas by mask plate, exposure area is exposed Light, the alkalinity additive in exposure area be changed into acidity by alkalinity, and the alkalinity additive in non-exposed areas is by retaining Alkalinity is quenched in exposure area and diffuses through the acid come.

Wherein, non-exposed areas is then quenched by alkalinity additive since stray light produces the sour of sour and exposure area diffusion It goes out.

The reaction equation of alkalinity additive and acid are as follows:

PDB+H⁺→PDBH⁺

Wherein, PDB indicates alkalinity additive.

In exposure process, acid (H can be generated in the following manner⁺) diffusion:

As shown in Fig. 2, being coated with photoresist 220 on object 210, light is irradiated to photoresist 220 by mask plate 230 Exposure area 221 and 222, exposure area 221 and 222 generate acid diffused to by way of diffusion non-exposed areas 223, 224 and 225.

As shown in figure 3, being coated with photoresist 220 on object 210, light is irradiated to photoresist 220 by mask plate 230 Exposure area 221 and 222 is irradiated to non-exposed areas 223,224 and 225 after light scattering, generates acid diffusion.

As shown in figure 4, being coated with photoresist 220 on object 210, light is irradiated to photoresist 220 by mask plate 230 The light of exposure area 221 and 222, diffraction is irradiated to non-exposed areas 223,224 and 225 by mask plate 230, generates acid and expands It dissipates.

As shown in figure 5, being coated with photoresist 220 on object 210, light is irradiated to photoresist 220 by mask plate 230 Exposure area 221 and 222, be irradiated to after exposure area 221 and 222 is reflected by the light of mask plate non-exposed areas 223, 224 and 225, generate acid diffusion.

Step 103, development treatment is carried out to photoresist, removes the photoresist of exposure area.

Illustratively, the photoresist of exposure area can be removed by the photoresist of developing solution dissolution exposure area.

Obviously, the above embodiments are merely examples for clarifying the description, and does not limit the embodiments.It is right For those of ordinary skill in the art, can also make on the basis of the above description it is other it is various forms of variation or It changes.There is no necessity and possibility to exhaust all the enbodiments.And it is extended from this it is obvious variation or It changes among the protection scope created still in the application.