A photoresist composition and use thereof

Abstract

The present application relates to the field of photoresist microelectronic chemistry, discloses a kind of photoresist composition and its application, photoresist composition includes the following components: by mass parts, phenolic resin 10-50 parts, photosensitizer 0.5-10 parts, auxiliary agent 0.1-10 parts and organic solvent 30-90 parts;The auxiliary agent includes one or more of the compounds shown in structural formula I: wherein, R1-R 10 Each independently selected from hydrogen, phenyl, C1-C 10 Alkyl, C5-C 10 Cycloalkyl, alcohol hydroxyl, phenolic hydroxyl, ether, ester group, Ra substituted amino, Ra substituted sulfonic acid group, halogenated group;Ra each independently selected from C5-C 10 Cycloalkyl, phenyl.The compound shown in formula I of the application is used as an additive of I-line photoresist, the resolution of photoresist can reach more than 0.5 μm, the sensitivity reaches 20 mJ / cm 2 , and the film retention rate can be maintained at more than 95%.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photoresist microelectronic chemistry, and in particular to a photoresist composition and application thereof. BACKGROUND

[0002] Photoresist is the core consumable material for integrated circuit manufacturing, and is also a key factor affecting the performance, yield and reliability of integrated circuits. I-line (365 nm) photoresist takes phenolic resin as the main resin, and diazonaphthoquinone as the photosensitizer. Through photoetching process procedures such as exposure and development, the pattern of the mask plate is transferred and copied to the wafer. I-line photoresist is widely used in the process of several hundred nanometers to several microns in integrated circuit manufacturing.

[0003] According to the chemical reaction mechanism and development principle of photoresist, photoresist can be divided into positive photoresist and negative photoresist. The exposed area of the positive photoresist will undergo photolysis reaction, which will degrade the photoresist into substances that can be dissolved in the developer, so that the non-exposed area of the photoresist can form a photoresist pattern that is the same or substantially the same as the mask pattern. The exposed area of the negative photoresist will undergo crosslinking reaction and cannot be dissolved in the developer, and the non-exposed area can be dissolved in the developer, so that the non-exposed area of the photoresist can form a photoresist pattern that is complementary or substantially complementary to the mask pattern.

[0004] In the manufacturing of integrated circuits, the resolution of photoresist directly affects the precision performance of the photoetching device, and the sensitivity directly affects the exposure efficiency (energy consumption, exposure time, etc.) in the photoetching process. In order to improve the sensitivity of photoresist, the mainstream KrF, ArF and EUV photoresist currently uses a chemical amplification type photosensitive resin. At present, the commercialized photoresist materials independently developed by China mainly include phenolic resin, poly-p-hydroxystyrene, etc., which are mainly used in G-line (436 nm) and I-line (365 nm) photoetching processes. The sensitivity of the phenolic resin-diazonaphthoquinone system G / I-line photoresist is relatively low. How to improve the photoetching efficiency and resolution of photoresist is the focus of the current development of photoresist product formula. Making the entire photoresist formula have good resolution and sensitivity has always been the direction that needs to be focused on in the industry. SUMMARY

[0005] In order to solve the above technical problems, the present application provides a photoresist composition and application thereof.

[0006] The technical scheme of the present application is as follows:

[0007] A photoresist composition, comprising the following components in mass fraction: phenolic resin 10-50 parts, photosensitizer 0.5-10 parts, auxiliary agent 0.1-10 parts and organic solvent 30-90 parts;

[0008] The auxiliary agent includes one or more of the compounds shown in structural formula I:

[0009]

[0010] R1-R4are each independently selected from the group consisting of hydrogen, phenyl, C1-C6alkyl, C5-C6cycloalkyl, alcoholic hydroxyl, phenolic hydroxyl, ether, ester, Ra-substituted amino, Ra-substituted sulfonic acid, halogen; each Ra is independently selected from the group consisting of C5-C6cycloalkyl, phenyl. 10 R1-R4are each independently selected from the group consisting of hydrogen, phenyl, C1-C6alkyl, C5-C6cycloalkyl, alcoholic hydroxyl, phenolic hydroxyl, ether, ester, Ra-substituted amino, Ra-substituted sulfonic acid, halogen; each Ra is independently selected from the group consisting of C5-C6cycloalkyl, phenyl. 10 R1-R4are each independently selected from the group consisting of hydrogen, phenyl, C1-C6alkyl, C5-C6cycloalkyl, alcoholic hydroxyl, phenolic hydroxyl, ether, ester, Ra-substituted amino, Ra-substituted sulfonic acid, halogen; each Ra is independently selected from the group consisting of C5-C6cycloalkyl, phenyl. 10 R1-R4are each independently selected from the group consisting of hydrogen, phenyl, C1-C6alkyl, C5-C6cycloalkyl, alcoholic hydroxyl, phenolic hydroxyl, ether, ester, Ra-substituted amino, Ra-substituted sulfonic acid, halogen; each Ra is independently selected from the group consisting of C5-C6cycloalkyl, phenyl. 10 R1-R4are each independently selected from the group consisting of hydrogen, phenyl, C1-C6alkyl, C5-C6cycloalkyl, alcoholic hydroxyl, phenolic hydroxyl, ether, ester, Ra-substituted amino, Ra-substituted sulfonic acid, halogen; each Ra is independently selected from the group consisting of C5-C6cycloalkyl, phenyl.

[0011] Preferably, the phenolic resin is 20-30 parts by mass, the photosensitizer is 3±1 parts by mass, the auxiliary agent is 0.3±0.1 parts by mass, and the solid content of the photoresist composition is 30±5%.

[0012] Preferably, the auxiliary agent is at least one of the following compounds:

[0013]

[0014] Preferably, the photosensitizer is formed by reacting diazonium naphthoquinone with a polyphenolic hydroxyl compound, and the molar ratio of the polyphenolic hydroxyl compound to the diazonium naphthoquinone is 1:1-1:4, more preferably 1:2-1:3.

[0015] Preferably, the diazonium naphthoquinone includes one or both of 2-diazonium-1 naphthoquinone-4-sulfonyl chloride and 2-diazonium-1 naphthoquinone-5-sulfonyl chloride; and the polyphenolic hydroxyl compound includes one or more of 2,3,4-trihydroxydiphenylmethane, 2,3,4,4'-tetrahydroxydiphenylmethane, 2,3,4-trihydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2',3,4-tetrahydroxybenzophenone, and 2,3',4,4'-tetrahydroxybenzophenone.

[0016] Preferably, the photosensitizer includes at least one of compounds G1 and G2; wherein compound G1 is formed by reacting 2,3,4,4'-tetrahydroxybenzophenone and 2-diazonium-1 naphthoquinone-4-sulfonyl chloride at a molar ratio of 1:2; and compound G2 is formed by reacting 2,3,4,4'-tetrahydroxybenzophenone and 2-diazonium-1 naphthoquinone-4-sulfonyl chloride at a molar ratio of 1:3.

[0017] Preferably, the phenolic resin is a polymer formed by condensation polymerization of a cresol compound and an aldehyde compound; the cresol compound includes one or more of m-cresol, p-cresol, o-cresol, dimethyl phenol, and trimethyl phenol; and the aldehyde compound includes one or more of formaldehyde, acetaldehyde, and propyl aldehyde.

[0018] Preferably, the phenolic resin is formed by condensation polymerization of m-cresol and p-cresol with formaldehyde, and the molar ratio of m-cresol to p-cresol is 1:(1-1.5).

[0019] Preferably, the phenolic resin has a molecular weight of 1000-20000 kg / mol, preferably 2000-10000 kg / mol, and more preferably 3000-8000 kg / mol.

[0020] Preferably, the organic solvent comprises one or more of anisole, propylene glycol methyl ether acetate, propylene glycol monomethyl ether, methyl isobutyl ketone, cyclopentanone, cyclohexanone, methyl ethyl ketone, diheptanone, ethyl lactate, ethyl acetate, butyl acetate, neopentyl acetate, dimethylbenzene, and toluene.

[0021] In addition, the components of the photoresist composition can also include a leveling agent, etc., and the type and amount of the leveling agent are not particularly limited in the present application. The leveling agent can reduce the surface tension of the photoresist composition, promote the uniform distribution of the photoresist layer prepared from the photoresist composition, and prevent the occurrence of spots or scars, etc.

[0022] The preparation method of the photoresist composition is not particularly limited and can comprise the following steps: adding the phenolic resin, the photosensitizer, the plasticizer, the additive, and the organic solvent into a light-shielded glassware in the order of the formulation ratio, and oscillating for 12-96 hours to allow them to be fully dissolved; then filtering the photoresist solution with a filter having a pore size of 0.5 microns or less; and collecting the filtrate in a light-shielded glass to obtain the photoresist composition.

[0023] The sensitivity test method is not particularly limited: using a coating machine to coat a 2-inch silicon wafer, adjusting the rotation speed of the spin coating according to the thickness of the photoresist layer, and after the spin coating is completed, performing baking to form a photoresist layer of a certain thickness; performing exposure on the photoresist layer with different doses by using a light barrier containing a 1-centimeter-diameter circular hole under 365 nm radiation; then developing the photoresist layer with a 2.38 wt% aqueous solution of tetramethylammonium hydroxide; measuring the residual thickness of the photoresist film layer after development under different exposure doses, and the dose corresponding to the pattern with a zero thickness of the photoresist film layer is the sensitivity of the photoresist.

[0024] The baking temperature is 50-150°C, and the baking time is 0.5-5 minutes, preferably the temperature is 90-100°C, and the time is 30-60 seconds.

[0025] The developing time is 10-180 seconds, and the preferred developing time is 30-60 seconds.

[0026] The resolution test method is not specially limited: using a coating machine to coat on a 2-inch silicon wafer, adjusting the rotation speed of the spin coating according to the thickness of the photoresist layer, after spin coating, baking to form a photoresist layer with a certain thickness; exposing under 365nm radiation, the mask plate is provided with a line width of 3-0.35μm, the ratio of line width to grating pitch is 1:1-1:5, then developing with 2.38wt% tetramethylammonium hydroxide aqueous solution; the minimum line width that can be clearly observed after development.

[0027] The baking temperature is 50-150℃, and the time is 0.5-5min, preferably the temperature is 90-100℃, and the time is 30-60s.

[0028] The developing time is 10-180s, preferably the developing time is 30-60s.

[0029] The photoresist composition prepared by the auxiliary agent screened in the application has excellent sensitivity and resolution. The photoresist composition can be applied to G-line photoresist or I-line photoresist.

[0030] Compared with the prior art, the application has the following beneficial effects:

[0031] 1) The compound represented by formula I in the application can significantly improve the sensitivity and resolution of the photoresist when added as an auxiliary agent to the photoresist composition.

[0032] 2) As an additive of I-line photoresist, the photoresist resolution of the compound represented by formula I in the application can reach more than 0.5μm, the sensitivity can reach 20mJ / cm 2 , and the film retention rate can be maintained at more than 95%. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is the SEM morphology diagram of the photoresist composition obtained in Example 3 after exposure.

[0034] Figure 2 is the SEM morphology diagram of the photoresist composition obtained in Example 9 after exposure.

[0035] Figure 3 is the SEM morphology diagram (a) and the cross-sectional diagram (b) of the photoresist composition obtained in Example 11 after exposure. DETAILED DESCRIPTION

[0036] The application will be further specifically and in detail described below in combination with specific examples, but the implementation manner of the application is not limited thereto, and for the process parameters not specially indicated, the conventional technology can be referred to.

[0037] Example 1

[0038] Preparation of photoresist composition

[0039] A photoresist composition was obtained by dissolving 20 parts of phenol resin F1, 3 parts of photosensitizer G2, 0.3 parts of additive of formula II and 0.01 parts of leveling agent fluoro glycol in PGMEA to make a solution with a solid content of 30%, and filtering with a filter membrane with a pore size of 0.2 microns. The phenol resin F1 was obtained by condensation polymerization of m-cresol and p-cresol with formaldehyde, and the molar ratio of m-cresol to p-cresol was 1:1, and the molecular weight of F1 was 4700 kg / mol.

[0040] Example 2

[0041] Except that the additive of formula III was used in the preparation of the photoresist composition, the rest was the same as example 1.

[0042] Example 3

[0043] Except that the additive of formula IV was used in the preparation of the photoresist composition, the rest was the same as example 1.

[0044] Example 4

[0045] Except that the additive of formula V was used in the preparation of the photoresist composition, the rest was the same as example 1.

[0046] Example 5

[0047] Except that the additive of formula VI was used in the preparation of the photoresist composition, the rest was the same as example 1.

[0048] Example 6

[0049] Preparation of photoresist composition

[0050] A photoresist composition was obtained by dissolving 20 parts of phenol resin F2, 3 parts of photosensitizer G2, 0.3 parts of additive of formula IV and 0.01 parts of leveling agent fluoro glycol in PGMEA to make a solution with a solid content of 30%, and filtering with a filter membrane with a pore size of 0.2 microns. The phenol resin F2 was obtained by condensation polymerization of m-cresol and p-cresol with formaldehyde, and the molar ratio of m-cresol to p-cresol was 1:1.5, and the molecular weight of F2 was 8000 kg / mol.

[0051] Example 7

[0052] Except that the photosensitizer of formula G1 was used in the preparation of the photoresist composition, the rest was the same as example 6.

[0053] Example 8

[0054] Except that the photosensitizer of formula G1:G2=1:1 mixture was used in the preparation of the photoresist composition, the rest was the same as example 6.

[0055] Example 9

[0056] The rest is the same as Example 1 except that no adjuvant is added in the preparation of the photoresist composition.

[0057] Example 10

[0058] The rest is the same as Example 1 except that the adjuvant is selected from (Formula VII) in the preparation of the photoresist composition.

[0059] Example 11

[0060] The rest is the same as Example 1 except that the adjuvant is selected from adjuvant Formula IV, 0.2% in the preparation of the photoresist composition.

[0061] Example 12

[0062] Sensitivity test:

[0063] The photoresist composition is coated on a 2-inch silicon wafer using a coater, the rotation speed of the coating is adjusted according to the thickness of the photoresist layer, after the coating is completed, the film is baked to harden at 100°C for 60s, and the film thickness is measured after cooling to form a 0.5μm photoresist layer; the photoresist layer is exposed to 365nm radiation, and a light barrier containing a 1cm diameter circular hole is used to expose the photoresist layer to different doses; then, the photoresist layer is developed with 2.38wt% aqueous tetramethylammonium hydroxide solution for 60s; the residual thickness of the photoresist film layer after development under different exposure doses is measured, and the dose corresponding to the pattern with a photoresist film layer thickness of zero is the sensitivity of the photoresist composition.

[0064] Resolution test:

[0065] The photoresist composition is coated on a 2-inch silicon wafer using a coater, the rotation speed of the coating is adjusted according to the thickness of the photoresist layer, after the coating is completed, the film is baked to harden, and the film thickness is measured after cooling to form a 0.5μm photoresist layer; the photoresist layer is exposed to 365nm radiation, and a mask plate is provided with a line width of 3-0.35μm, the ratio of line width to grating pitch is 1:1, and then the photoresist layer is exposed, and then developed with 2.38wt% aqueous tetramethylammonium hydroxide solution; the minimum line width that can be clearly observed after development.

[0066] Table 1

[0067]

[0068] The sensitivity of the photoresist composition without adjuvant (Example 9) is much lower than that of the photoresist composition with adjuvant (Example 3) compared with the photoresist composition with adjuvant. By adjusting the amount of adjuvant added, the resolution and sensitivity of the photoresist composition can be optimized (Example 11, resolution 0.45μm, sensitivity 35mJ / cm 2), which is much better than the photoresist composition without the addition of the auxiliary agent (Example 9, resolution 0.6 μm, sensitivity 80 mJ / cm 2 ).

[0069] The above examples are the preferred embodiments of the present application, but the embodiments of the present application are not limited to the above examples, and any changes, modifications, substitutions, combinations, simplifications, etc. made without departing from the spirit and principles of the present application are equivalent replacement modes and are included in the scope of the present application.

Claims

1. A photoresist composition, characterized in that, By weight, it includes the following main components: 10-50 parts phenolic resin, 0.5-10 parts photosensitizer, 0.1-10 parts additives, and 30-90 parts organic solvent; The photosensitizer is formed by reacting diazonoquinone with a polyphenolic hydroxy compound, wherein the molar ratio of the polyphenolic hydroxy compound to diazonoquinone is 1:1 to 1:

4. The adjuvant includes one or more of the compounds shown in structural formula I: Among them, R1-R 10 Each is independently selected from hydrogen, phenyl, C1-C 10 Alkyl, C5-C 10 The cycloalkyl, alcohol hydroxyl, phenolic hydroxyl, ether, ester group, Ra-substituted amino group, Ra-substituted sulfonic acid group, and halogen group; Ra is independently selected from C5-C6. 10 cycloalkyl, phenyl; R1-R 10 Not all of them are selected from hydrogen.

2. The photoresist composition according to claim 1, characterized in that, The photoresist composition also includes a leveling agent.

3. The photoresist composition according to claim 1 or 2, characterized in that, The composition comprises 20-30 parts by weight of phenolic resin, 3±1 parts of photosensitizer, 0.3±0.1 parts of additives, and 30±5% solid content of photoresist composition.

4. The photoresist composition according to claim 1 or 2, characterized in that, The adjuvant is at least one of the following compounds:

5. The photoresist composition according to claim 4, characterized in that, The diazonoquinone includes one or both of 2-diazo-1-naphthoquinone-4-sulfonyl chloride and 2-diazo-1-naphthoquinone-5-sulfonyl chloride; the polyphenolic hydroxy compound includes one or more of 2,3,4-trihydroxydiphenylmethane, 2,3,4,4'-tetrahydroxydiphenylmethane, 2,3,4-trihydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2',3,4-tetrahydroxybenzophenone, and 2,3',4,4'-tetrahydroxybenzophenone.

6. The photoresist composition according to claim 5, characterized in that, The photosensitizer includes at least one of compounds G1 and G2; wherein compound G1 is prepared by reacting 2,3,4,4'-tetrahydroxybenzophenone and 2-diazo-1-naphthoquinone-4-sulfonyl chloride in a molar ratio of 1:2; and compound G2 is prepared by reacting 2,3,4,4'-tetrahydroxybenzophenone and 2-diazo-1-naphthoquinone-4-sulfonyl chloride in a molar ratio of 1:

3.

7. The photoresist composition according to claim 6, characterized in that, The phenolic resin is a polymer formed by the condensation polymerization reaction of cresol compounds and aldehyde compounds; the cresol compounds include one or more of m-cresol, p-cresol, methylcresol, xylenol and tricresol; the aldehyde compounds include one or more of formaldehyde, acetaldehyde and propionaldehyde.

8. The photoresist composition according to claim 7, characterized in that, The phenolic resin is formed by the condensation polymerization reaction of m-cresol and p-cresol with formaldehyde, and the molar ratio of m-cresol to p-cresol is 1:(1-1.5).

9. The photoresist composition according to claim 8, characterized in that, The molecular weight of the phenolic resin is 1000-20000 kg / mol.

10. The photoresist composition according to claim 9, characterized in that, The molecular weight of the phenolic resin is 2000-10000 kg / mol.

11. The photoresist composition according to claim 10, characterized in that, The molecular weight of the phenolic resin is 3000-8000 kg / mol.

12. The photoresist composition according to claim 11, characterized in that, The organic solvent includes one or more of anisole, propylene glycol methyl ether acetate, propylene glycol monomethyl ether, methyl isobutyl ketone, cyclopentanone, cyclohexanone, methyl ethyl ketone, diheptanone, ethyl lactate, ethyl acetate, butyl acetate, neopentyl acetate, xylene, and toluene.

13. The use of the photoresist composition according to any one of claims 1-12 as a G / I line photoresist.

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