TWI850743B - Assisted feature placement in semiconductor patterning - Google Patents

Abstract

A method of microfabrication includes providing a substrate having an existing pattern, wherein the existing pattern includes features formed within a base layer such that a top surface of the substrate has features uncovered and the base layer is uncovered, depositing a selective attachment agent on the substrate, wherein the selective attachment agent comprises a solubility-shifting agent, depositing a first resist on the substrate, activating the solubility shifting agent such that a portion of the first resist becomes insoluble to a first developer, and developing the first resist using the first developer such that the portion of the first resist insoluble to the first developer remains.

Description

Assisted topography placement in semiconductor patterning

The present invention relates to assisting topographical body placement in semiconductor patterning.

Invention Background

Microfabrication of semiconductor devices includes various steps such as film deposition, pattern formation, and pattern transfer. Materials and films are deposited on a substrate by spin coating, vapor deposition, and other deposition methods. Pattern formation is typically performed by exposing a photosensitive film called a photoresist to a pattern of actinic radiation and then developing the photoresist to form a relief pattern. The relief pattern then acts as an etch mask, covering portions of the substrate that will not be etched when one or more etching processes are applied to the substrate. Thus, patterns that make up functional devices such as transistors and diodes are formed on the substrate, and the substrate is then further processed.

Semiconductor patterning includes a conventional process flow. A substrate layer with a certain pattern is received. The pattern is smoothed and a transfer layer is placed to improve the pattern shape. Next, a photoresist and related layers are deposited on the surface. The photoresist layer is exposed to the pattern by lithography, thereby producing a latent pattern. The latent pattern is then developed, thereby forming a relief pattern that is resistant to the etchant to be used as an etch mask. Finally, this relief pattern is etched into the transfer layer and then etched into the final substrate.

Summary of the invention

This invention content is provided to introduce a series of concepts, which are further described in the following embodiments. This invention content is not intended to identify the key features or essential features of the claimed subject matter, nor is it intended to be used to assist in limiting the scope of the claimed subject matter.

In one aspect, embodiments disclosed herein relate to a method of microfabrication, comprising providing a substrate having an existing pattern, wherein the existing pattern includes a morphology formed in a base layer such that a top surface of the substrate has uncovered morphology and the base layer is uncovered; depositing a selective adhesive on the substrate, wherein the selective adhesive includes a solubility shifting agent; depositing a first resist on the substrate; activating the solubility shifting agent such that a portion of the first resist becomes insoluble in a first developer; and developing the first resist using the first developer such that the portion of the first resist that is insoluble in the first developer remains.

In another aspect, an embodiment of the present disclosure relates to a method of microfabrication, which includes providing a substrate having an existing pattern, wherein the existing pattern includes a morphology formed in a base layer, such that a top surface of the substrate has an uncovered morphology and the base layer is uncovered; depositing a selective adhesive on the substrate, wherein the selective adhesive includes a solubility shifting agent; depositing a first resist on the substrate; activating the solubility shifting agent such that a portion of the first resist becomes soluble in a first developer; and developing the first resist using the first developer such that the portion of the first resist soluble in the first developer is removed.

Other aspects and advantages of the claimed subject matter will become apparent from the following description and appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The challenge in substrate patterning is to accurately place the designed pattern relative to the underlying topography, thereby accurately shaping the final pattern. Another challenge is to accurately size the final pattern as designed. Small variations in size and shape can lead to short-term and long-term device failures.

As will be appreciated by those of ordinary skill in the art, films and materials added to and removed from a given substrate can cause the materials and structures of the substrate upon which the shape is formed to experience internal compressive and tensile stresses. These internal stresses can cause the substrate to warp and bow. Additionally, printing patterns at or below the resolution of a given photolithography tool generally means a higher likelihood of pattern misalignment. Thus, a significant challenge is that a placed (exposed) pattern can shift from a previous pattern. This "alignment" error or "overlap" error is one of the most significant challenges in device microfabrication. This challenge applies to layers that overlap each other as well as layers that are close to each other.

Therefore, there is a great need to improve pattern placement on a given subsequent layer. Learned pattern placement attempts to improve pattern placement in lithography systems tend to involve the use of highly accurate metrology and complex feedback loops.

The present disclosure generally relates to a method for pattern placement on a semiconductor substrate. As used herein, the terms "semiconductor substrate" and "substrate" are used interchangeably and may be any semiconductor material, including but not limited to semiconductor wafers, semiconductor material layers, and combinations thereof. The method disclosed herein provides for local and direct improved pattern placement and overlay by inducing the pattern to form in the correct place (e.g., a target location or target area). To achieve self-aligned pattern placement, the method may include guiding the location of pattern formation or inhibiting pattern formation in undesired locations. In one or more embodiments, the method includes depositing or forming an auxiliary layer at the target location.

Methods according to the present disclosure may include providing a substrate having an existing pattern, and then selectively forming a material pattern on top of or alternating with the existing pattern. A material pattern selectively formed on top of an existing pattern according to one or more embodiments is shown in FIG. 1A. A material pattern selectively formed according to one or more embodiments that alternates with or is offset from an existing pattern included on a substrate is shown in FIG. 1B.

A method 200 for selective pattern self-alignment (e.g., the pattern shown in FIG. 1A ) according to the present disclosure is shown in FIG. 2 and discussed with reference thereto. Initially, at block 202, an existing pattern is provided on a substrate. At block 204, the substrate or a portion thereof is coated with a selective adhesive. The selective adhesive may covalently bond to the surface. The selective adhesive coating may optionally be pre-treated. The optional pre-treatment may be a heat treatment. The heat treatment may promote a condensation reaction between the selective adhesive and the surface. Next, at block 206, the substrate is coated with a first resist. A solubility-shifting agent may be provided on the first resist, and then the solubility-shifting agent may be activated to provide regions of the first resist that are soluble in the first developer as shown at block 208. Finally, the first resist is developed at block 210 to provide a selective pattern of the first resist.

Schematic diagrams of a coated substrate at various time points during the method described above are shown in Figures 3A-3E. In this article, "coated substrate" refers to a substrate coated with one or more layers, such as a first resist layer and a second resist layer. Figure 3A shows a substrate including an existing pattern. Figure 3B shows a substrate including an outer coating layer, which includes a selective adhesive. Figure 3C shows a substrate including an outer coating layer of a selective adhesive, which is superimposed with a first resist. Finally, Figure 3D shows a coated substrate after the first resist has been developed so that a portion of the substrate is exposed. The method of FIG. 2 and the coated substrate shown in FIGS. 3A-D are discussed in detail below.

In FIG. 2 , at block 202, an existing pattern is provided on a substrate. FIG. 3A shows a substrate including an existing pattern. In FIG. 3A , the existing pattern includes a morphology 302 formed in a base layer 301. The base layer may be any suitable substrate known in the art. In one or more embodiments, the morphology includes a metal or other conductive structure. As used herein, the term metal includes alloys, stacks, and other combinations of multiple metals. For example, a metal interconnect may include a barrier layer, a stack of different metals or alloys, and the like. Suitable metals that may be present in the morphology include, but are not limited to, copper, cobalt, and tungsten. In one or more embodiments, the base layer is an interlayer dielectric. Suitable interlayer dielectrics may include oxides of silicon (e.g., silicon dioxide ( _SiO2 )), doped oxides of silicon, fluorinated oxides of silicon, carbon doped oxides of silicon, various low-k dielectric materials known in the art, and combinations thereof. The existing pattern may be a final feature or an intermediate feature in a patterning process. In some embodiments, the substrate is planarized so that the existing pattern is uncovered and accessible.

Next, at block 204, a selective adhesive is applied to the substrate or a portion thereof. The selective adhesive may be applied to the substrate by any coating method known in the art. Suitable coating methods include, but are not limited to, vapor deposition, spin coating, and Langmuir-Blodgett monolayer coating. In one or more embodiments, the selective adhesive is applied to a target area. As used herein, a "target area" or "target location" refers to an area on a substrate that is to receive a pattern.

The selective adhesive may preferentially adhere to a material of an existing pattern. In one or more embodiments, the selective adhesive adheres to a morphology of an existing pattern. FIG. 3B shows a substrate coated with a selective adhesive 303 that adheres to a morphology of an existing pattern. The selective adhesive may adhere to the morphology of the pattern at a ratio greater than 1:1. As an example and not a limitation, the selective adhesive may adhere to the morphology of the pattern at a ratio of morphology to substrate in the range of 2:1 to 10:1.

In one or more embodiments, the selective attachment agent is a chemical functional group that can be further functionalized. Exemplary selective attachment agents include, but are not limited to, silanes, alkenes, alkynes, alcohols, silanols, amines, phosphines, phosphonic acids, and carboxylic acids. The specific selective attachment agent applied to the existing pattern may depend on the specific chemical substances used in other components of the method 200. For example, various phosphonic acids and esters are able to react selectively or at least preferentially with native or oxidized metal surfaces to preferentially or even selectively form strong bonding metal phosphonates relative to the surface of dielectric materials (such as silicon oxides), and can therefore be used as a selective attachment agent applied to the topography in the base layer. One specific example of a suitable phosphonic acid is octadecylphosphonic acid (ODPA). Such surface coatings generally tend to be stable in many organic solvents, but can be removed using weak acids and aqueous alkaline solutions. Phosphines (e.g., organic phosphines) may also be used optionally. Other common acids, such as sulfonic acids, sulfinic acids, and carboxylic acids may also be used optionally.

Another example of a reaction that is selective or at least preferential to metal materials as compared to dielectric materials or organic polymeric materials or other materials is various metal corrosion inhibitors, such as those used to protect interconnect structures during chemical mechanical polishing. Specific examples include benzotriazole, other triazole functional groups, other suitable heterocyclic groups (such as heterocyclic-based corrosion inhibitors), and other metal corrosion inhibitors known in the art. In addition to triazole groups, other functional groups can be used to provide the desired attraction or reactivity to metals. Various metal chelators may also be suitable. Various amines (such as organic amines) may also be suitable.

Yet another example of a reaction that is selective or at least preferential to metal materials as compared to dielectric materials or organic polymeric materials or other materials is various thiols. As another example, 1,2,4-triazole or similar aromatic heterocyclic compounds can be used to selectively react with metals as compared to dielectrics and certain other materials. The selective attachment agent may also contain functional groups that are capable of reacting with the functional groups of the polymer to bond the polymer to the surface. Various other metal poisoning compounds known in the art may also potentially be used. It should be understood that these are only a few illustrative examples and that still other examples will be apparent to those skilled in the art and having the benefit of this disclosure. The selective attachment agent may also include a polymer containing any of the aforementioned functional groups capable of selective attachment, wherein the polymer has the functional groups along the backbone or as terminal groups and forms a polymer chain layer attached to the target material.

In one or more embodiments, the selective adhesive includes a solubility-shifting agent. The composition of the solubility-shifting agent may depend on the selective adhesive. As will be generally understood by those skilled in the art, any suitable solubility-shifting agent may be included in the selective adhesive, with the proviso that the two materials do not react with each other. Generally speaking, the solubility-shifting agent may be any chemical substance that is activated by light or heat. For example, in some embodiments, the solubility-shifting agent includes an acid or a thermal acid generator (TAG). The acid or the acid generated in the case of a TAG should be sufficient to heat and cause bond cleavage of the acid-decomposable groups of the polymer in the surface region of the first resist pattern, so that the solubility of the first resist polymer in the specific developer to be applied is increased. The acid or TAG is generally present in the composition in an amount of about 0.01 to 20 wt %, based on the total solids of the trimming composition.

Preferred acids are organic acids, including non-aromatic acids and aromatic acids, each of which may optionally have fluorine substitution. Suitable organic acids include, for example, carboxylic acids such as alkanoic acids, including formic acid, acetic acid, propionic acid, butyric acid, dichloroacetic acid, trichloroacetic acid, perfluoroacetic acid, perfluorooctanoic acid, oxalic acid, malonic acid and succinic acid; hydroxyalkanoic acids such as citric acid; aromatic carboxylic acids such as benzoic acid, fluorobenzoic acid, hydroxybenzoic acid and naphthoic acid; organic phosphoric acids such as dimethylphosphoric acid, dimethylphosphinic acid; and sulfonic acids such as optionally fluorinated alkylsulfonic acids, including methanesulfonic acid, trifluoromethanesulfonic acid, ethanesulfonic acid, 1-butanesulfonic acid, 1-perfluorobutanesulfonic acid, 1,1,2,2-tetrafluorobutane-1-sulfonic acid, 1,1,2,2-tetrafluoro-4-hydroxybutane-1-sulfonic acid, 1-pentanesulfonic acid, 1-hexanesulfonic acid and 1-heptanesulfonic acid.

Exemplary fluorine-free aromatic acids include aromatic acids of the general formula (I):

wherein: R1 independently represents a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C5-C20 aryl group, or a combination thereof, which optionally contains one or more groups selected from carbonyl, carbonyloxy, sulfonamide, ether, thioether, substituted or unsubstituted alkylene, or a combination thereof; Z1 independently represents a group selected from carboxyl, hydroxyl, nitro, cyano, C1 to C5 alkoxy, formyl, and sulfonic acid; a and b independently represent integers from 0 to 5; and a+b is 5 or less.

Exemplary aromatic acids may have the general formula (II):

wherein: R2 and R3 each independently represent a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C5-C16 aryl group, or a combination thereof, which optionally contains one or more groups selected from carbonyl, carbonyloxy, sulfonamide, ether, thioether, substituted or unsubstituted alkylene, or a combination thereof; Z2 and Z3 each independently represent a group selected from carboxyl, hydroxyl, nitro, cyano, C1 to C5 alkoxy, formyl, and sulfonic acid; c and d are independently integers from 0 to 4; c+d is 4 or less; e and f are independently integers from 0 to 3; and e+f is 3 or less.

Additional aromatic acids that may be included in the solubility shifter include those of formula (III) or (IV):

wherein: R4, R5 and R6 each independently represent a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C5-C12 aryl group or a combination thereof, which optionally contains one or more groups selected from carbonyl, carbonyloxy, sulfonamide, ether, thioether, substituted or unsubstituted alkylene or a combination thereof; Z4, Z5 and Z6 each independently represent a group selected from carboxyl, hydroxyl, nitro, cyano, C1 to C5 alkoxy, formyl and sulfonic acid; g and h are independently integers from 0 to 4; g+h is 4 or less; i and j are independently integers from 0 to 2; i+j is 2 or less; k and l are independently integers from 0 to 3; and k+l is 3 or less;

wherein: R4, R5 and R6 each independently represent a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C5-C12 aryl group or a combination thereof, which optionally contains one or more groups selected from carbonyl, carbonyloxy, sulfonamide, ether, thioether, substituted or unsubstituted alkylene or a combination thereof; Z4, Z5 and Z6 each independently represent a group selected from carboxyl, hydroxyl, nitro, cyano, C1 to C5 alkoxy, formyl and sulfonic acid; g and h are independently integers from 0 to 4; g+h is 4 or less; i and j are independently integers from 0 to 1; i+j is 1 or less; k and l are independently integers from 0 to 4; and k+l is 4 or less.

Suitable aromatic acids may alternatively have the general formula (V):

wherein: R7 and R8 each independently represent a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C5-C14 aryl group, or a combination thereof, which optionally contains one or more groups selected from carboxyl, carbonyl, carbonyloxy, sulfonamide, ether, thioether, substituted or unsubstituted alkylene, or a combination thereof; Z7 and Z8 each independently represent a group selected from hydroxyl, nitro, cyano, C1 to C5 alkoxy, formyl, and sulfonic acid; m and n are independently integers from 0 to 5; m+n is 5 or less; o and p are independently integers from 0 to 4; and o+p is 4 or less.

Additionally, exemplary aromatic acids may have the general formula (VI):

wherein: X is O or S; R9 independently represents a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C5-C20 aryl group, or a combination thereof, which optionally contains one or more groups selected from carbonyl, carbonyloxy, sulfonamide, ether, thioether, substituted or unsubstituted alkylene, or a combination thereof; Z9 independently represents a group selected from carboxyl, hydroxyl, nitro, cyano, C1 to C5 alkoxy, formyl, and sulfonic acid; q and r independently represent integers from 0 to 3; and q+r is 3 or less.

In one or more embodiments, the acid is a fluorine-substituted free acid. Suitable fluorine-substituted free acids may be aromatic or non-aromatic. For example, fluorine-substituted free acids that can be used as solubility-shifting agents include, but are not limited to, the following:

Suitable TAGs include those capable of generating non-polymeric acids as described above. TAGs may be non-ionic or ionic. Suitable non-ionic thermal acid generators include, for example, cyclohexyl trifluoromethylsulfonate, methyl trifluoromethylsulfonate, cyclohexyl p-toluenesulfonate, methyl p-toluenesulfonate, cyclohexyl 2,4,6-triisopropylbenzenesulfonate, methyl nitrobenzyl ester, benzoin toluenesulfonate, 2-nitrobenzyl toluenesulfonate, tris(2,3-dibromopropyl)-1,3,5-tris(2,4,6-trione), alkyl esters of organic sulfonic acids, p-toluenesulfonic acid, dodecylbenzenesulfonate, Acid, oxalic acid, phthalic acid, phosphoric acid, camphorsulfonic acid, 2,4,6-trimethylbenzenesulfonic acid, triisopropylnaphthalenesulfonic acid, 5-nitro-o-toluenesulfonic acid, 5-sulfosalicylic acid, 2,5-dimethylbenzenesulfonic acid, 2-nitrobenzenesulfonic acid, 3-chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-fluorodecanoylsulfonic acid, dodecylbenzenesulfonic acid, 1-naphthol-5-sulfonic acid, 2-methoxy-4-hydroxy-5-benzoyl-benzenesulfonic acid and its salts, and combinations thereof. Suitable ionic thermal acid generators include, for example, triethylamine dodecylbenzenesulfonate, triethylamine dodecylbenzene disulfonate, ammonium p-toluenesulfonate, pyridine p-toluenesulfonate, sulfonates such as carbocyclic aryl and heteroaryl sulfonates, aliphatic sulfonates, and benzenesulfonates. Compounds that generate sulfonic acid upon activation are generally suitable. Preferred thermal acid generators include ammonium p-toluenesulfonate and heteroaryl sulfonates.

Preferably, TAG is in ionic form, wherein the reaction process for generating sulfonic acid is as follows:

Wherein RSO ₃ ⁻ is a TAG anion and X ⁺ is a TAG cation, preferably an organic cation. The cation may be a nitrogen-containing cation of the general formula (I):

(BH) ⁺ (I)

It is a monoprotonated form of a nitrogen-containing base B. Suitable nitrogen-containing bases B include, for example, optionally substituted amines such as ammonia, difluoromethylamine, C1-20 alkylamines and C3-30 arylamines, such as nitrogen-containing heteroaromatic bases such as pyridine or substituted pyridines (e.g. 3-fluoropyridine), pyrimidine and pyrrolidone; nitrogen-containing heterocyclic groups such as oxazole, oxazoline or thiazoline. The aforementioned nitrogen-containing base B may be optionally substituted, for example, by one or more groups selected from alkyl groups, aryl groups, halogen atoms (preferably fluorine), cyano groups, nitro groups and alkoxy groups. Among them, base B is preferably a heteroaromatic base.

Base B typically has a pKa of 0 to 5.0, or between 0 and 4.0, or between 0 and 3.0, or between 1.0 and 3.0. As used herein, the term "pKa" is used according to its recognized meaning in the art, that is, pKa is the negative logarithm (base 10) of the dissociation constant of the conjugate acid (BH) ⁺ of the basic moiety (B) in aqueous solution at about room temperature. In certain embodiments, the boiling point of base B is less than about 170°C, or less than about 160°C, 150°C, 140°C, 130°C, 120°C, 110°C, 100°C, or 90°C.

Exemplary suitable nitrogen-containing cations (BH) ⁺ include NH ₄ ⁺ , CF ₂ HNH ₂ ⁺ , CF ₃ CH ₂ NH ₃ ⁺ , (CH ₃ ) ₃ NH ⁺ , (C ₂ H ₅ ) ₃ NH ⁺ , (CH ₃ ) ₂ (C ₂ H ₅ ) NH ⁺ , and the following:

wherein Y is an alkyl group, preferably a methyl group or an ethyl group.

In certain embodiments, the solubility shifting agent may be an acid such as trifluoromethanesulfonic acid, perfluoro-1-butanesulfonic acid, p-toluenesulfonic acid, 4-dodecylbenzenesulfonic acid, 2,4-dinitrobenzenesulfonic acid, and 2-trifluoromethylbenzenesulfonic acid; an acid generator such as triphenylcopper sulfonate, perfluorobutanesulfonate, 3-fluorobutanesulfonate, 4-tert-butylphenyltetramethylenecopper sulfonate, 4-tert-butylphenyltetramethylenecopper sulfonate, 2-trifluoromethylbenzenesulfonate, and 4-tert-butylphenyltetramethylenecopper sulfonate 4,4,5,5,6,6-hexafluorodihydro-4H-1,3,2-dithiazolium 1,1,3,3-tetraoxide; or a combination thereof.

Alternatively, the solubility-shifting agent may include a base or a base generator. In such embodiments, suitable solubility-shifting agents include, but are not limited to, hydroxides, carboxylates, amines, imides, amides, and mixtures thereof. Specific examples of bases include ammonium carbonate, ammonium hydroxide, ammonium hydrogen phosphate, ammonium phosphate, tetramethylammonium carbonate, tetramethylammonium hydroxide, tetramethylammonium hydrogen phosphate, tetramethylammonium phosphate, tetraethylammonium carbonate, tetraethylammonium hydroxide, tetraethylammonium hydrogen phosphate, tetraethylammonium phosphate, and combinations thereof. Amines include aliphatic amines, cycloaliphatic amines, aromatic amines, and heterocyclic amines. Amines may be primary, secondary, or tertiary amines. Amines may be monoamines, diamines, or polyamines. Suitable amines may include C1-30 organic amines, imines or amides, or C1-30 quaternary ammonium salts which may be strong bases (e.g., hydroxides or alkoxides) or weak bases (e.g., carboxylates). Exemplary bases include amines such as tripropylamine, dodecylamine, tris(2-hydroxypropyl)amine, tetrakis(2-hydroxypropyl)ethylenediamine; arylamines such as diphenylamine, triphenylamine, aminephenols and 2-(4-aminophenyl)-2-(4-hydroxyphenyl)propane, Troger's alkali (Troger's base), hindered amines such as diazabicycloundecene (DBU) or diazabicyclononene (DBN), amides such as 1,3-dihydroxy-2-(hydroxymethyl)propan-2-ylcarbamic acid tributyl ester and 4-hydroxypiperidine-1-carboxylic acid tributyl ester; or ion quenchers including quaternary alkylammonium salts such as tetrabutylammonium hydroxide (TBAH) or tetrabutylammonium lactate. In another embodiment, the amine is a hydroxylamine. Examples of hydroxylamines include hydroxylamines having one or more hydroxyalkyl groups each having 1 to about 8 carbon atoms, and preferably 1 to about 5 carbon atoms, such as hydroxymethyl, hydroxyethyl and hydroxybutyl. Specific examples of hydroxylamines include monoethanolamine, diethanolamine and triethanolamine, 3-amino-1-propanol, 2-amino-2-methyl-1-propanol, 2-amino-2-ethyl-1,3-propanediol, tris(hydroxymethyl)aminomethane, N-methylethanolamine, 2-diethylamino-2-methyl-1-propanol and triethanolamine.

Suitable base generators may be thermal base generators. Thermal base generators form bases when heated above a first temperature, typically about 140° C. or higher. Thermal base generators may include functional groups such as amides, sulfonamides, imides, imines, O-acyl oximes, benzyloxycarbonyl derivatives, quaternary ammonium salts, nifedipine, carbamates, and combinations thereof. Exemplary thermal alkali generators include o-{(β-(dimethylamino)ethyl)aminocarbonyl}benzoic acid, o-{(γ-(dimethylamino)propyl)aminocarbonyl}benzoic acid, 2,5-bis{(β-(dimethylamino)ethyl)aminocarbonyl}terephthalic acid, 2,5-bis{(γ-(dimethylamino)propyl)aminocarbonyl}terephthalic acid, 2,4-bis{(β-(dimethylamino)ethyl)aminocarbonyl}isophthalic acid, 2,4-bis{(γ-(dimethylamino)propyl)aminocarbonyl}isophthalic acid, and combinations thereof.

Alternatively, in one or more embodiments, the solubility-shifting agent comprises a crosslinking agent. Suitable crosslinking agents that can be used as solubility-shifting agents include, but are not limited to, crosslinking agents used to cure bisepoxides, such as bisphenol A diglycidyl ether, 2,5-bis[(2-oxiranylmethoxy)-methyl]-furan, 2,5-bis[(2-oxiranylmethoxy)methyl]-benzene, melamine, glycoluril, such as tetramethoxymethyl glycoluril and tetrabutoxymethyl glycoluril, benzoguanamine-based materials, such as benzoguanamine, hydroxymethylbenzoguanamine, methylated hydroxymethylbenzoguanamine, ethylated hydroxymethylbenzoguanamine, and urea-based materials.

In one or more embodiments, the selective attachment agent includes a solvent. The solvent is typically selected from water, an organic solvent, and mixtures thereof. In some embodiments, the solvent may include an organic-based solvent system comprising one or more organic solvents. The term "organic-based" means that the solvent system includes greater than 50 wt% organic solvent based on the total solvent of the solubility shifter composition, more typically greater than 90 wt%, greater than 95 wt%, greater than 99 wt% or 100 wt% organic solvent based on the total solvent of the solubility shifter composition. The solvent component is typically present in an amount of 90 to 99 wt% based on the solubility shifter composition.

Organic solvents suitable for use in the selective attachment agent composition include, for example, alkyl esters such as alkyl propionates such as n-butyl propionate, n-pentyl propionate, n-hexyl propionate and n-heptyl propionate, and alkyl butyrates such as n-butyl butyrate, isobutyl butyrate and isobutyl isobutyrate; ketones such as 2,5-dimethyl-4-hexanone and 2,6-dimethyl-4-heptanone; aliphatic hydrocarbons such as n-heptane, n-nonane, n-octane, n-decane, 2-methylheptane, 3-methylheptane, 3,3-dimethylhexane and 2,3,4-trimethylpentane, and fluorinated aliphatic hydrocarbons such as perfluoroheptane; alcohols such as linear, branched or cyclic C4-C9 monohydric alcohols such as 1-butanol, 2-butanol, isobutanol, tert-butanol, 3-methyl-1-butanol, 1-pentanol, 2-pentanol, 4-methyl-2-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol and 4-octanol; 2,2,3,3,4,4-hexafluoro-1 -butanol, 2,2,3,3,4,4,5,5-octafluoro-1-pentanol and 2,2,3,3,4,4,5,5,6,6-decafluoro-1-hexanol, and C5-C9 fluorinated diols such as 2,2,3,3,4,4-hexafluoro-1,5-pentanediol, 2,2,3,3,4,4,5,5-octafluoro-1,6-hexanediol and 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoro-1,8-octanediol; ethers such as isoamyl ether and propanediol alcohol monomethyl ether; esters such as alkyl esters having a total carbon number of 4 to 10, for example propylene glycol monomethyl ether acetate, alkyl propionates such as n-butyl propionate, n-pentyl propionate, n-hexyl propionate and n-heptyl propionate, and alkyl butyrates such as n-butyl butyrate, isobutyl butyrate and isobutyl isobutyrate; ketones such as 2,5-dimethyl-4-hexanone and 2,6-dimethyl-4-heptanone; and polyethers such as dipropylene glycol monomethyl ether and tripropylene glycol monomethyl ether; and mixtures containing one or more of these solvents.

In some embodiments, after coating the substrate with the selective adhesive, the substrate is pretreated. The substrate can be pretreated to ensure that the selective adhesive is attached to the surface of the feature. The pretreatment can be a soft bake at a temperature in the range of 50 to 150° C. for about 30 seconds to 90 seconds.

After the selectively attached material is attached to the feature body, any excess material can be removed. Therefore, in one or more embodiments, after the selectively attached agent is applied to the substrate and optionally pre-treated, the substrate is rinsed to remove unused material.

Next, at block 206 of method 200, a first resist is deposited on the substrate. FIG. 3C shows a substrate coated with a selective adhesive 303 and a first resist 304. The first resist may be a photoresist. Generally speaking, a photoresist is a chemically amplified photosensitive composition comprising a polymer, a photoacid generator, and a solvent. In one or more embodiments, the first resist comprises a polymer. The polymer may be any standard polymer commonly used in resist materials, and may in particular be a polymer having acid-unstable groups. For example, the polymer may be a polymer made of monomers including vinyl aromatic monomers such as styrene and para-hydroxystyrene, acrylates, methacrylates, norbornene, and combinations thereof. Monomers including reactive functional groups may be present in the polymer in a protected form. For example, the -OH group of hydroxystyrene can be protected with a tertiary butoxycarbonyl protecting group. Such protecting groups can alter the reactivity and solubility of the polymer included in the first resistor. As will be appreciated by those skilled in the art, a variety of protecting groups can be used for this reason. Acid-unstable groups include, for example, tertiary alkyl ester groups, secondary or tertiary aryl ester groups, secondary or tertiary ester groups having a combination of alkyl and aryl groups, tertiary alkoxy groups, acetal groups or ketal groups. Acid-unstable groups are also commonly referred to in this art as "acid-decomposable groups", "acid-cleavable groups", "acid-cleavable protecting groups", "acid-unstable protecting groups", "acid-detachable groups" and "acid-sensitive groups".

The acid-labile group of the carboxylic acid formed on the polymer during decomposition is preferably a tertiary ester group of the formula -C(O)OC(R1)3 or an acetal group of the formula -C(O)OC(R2)2OR3, wherein: R1 is independently a straight chain C1-20 alkyl group, a branched chain C3-20 alkyl group, a monocyclic or polycyclic C3-20 cycloalkyl group, a straight chain C2-20 alkenyl group, a branched chain C3-20 alkenyl group, a monocyclic or polycyclic C3-20 cycloalkenyl group, a monocyclic or polycyclic C6-20 aryl group or a monocyclic or polycyclic C2-20 heteroaryl group, preferably a straight chain C1-6 alkyl group. R1 is independently hydrogen, fluorine, a straight-chain C1-20 alkyl group, a branched-chain C3-20 alkyl group, a monocyclic or polycyclic C3-20 cycloalkyl group, a straight-chain C2-20 alkenyl group, a branched-chain C3-20 alkenyl group, a monocyclic or polycyclic C3-10 cycloalkyl group, each of which is substituted or unsubstituted, each R1 optionally includes one or more groups selected from -O-, -C(O)-, -C(O)-O- or -S- as part of its structure, and any two R1 groups optionally form a ring together; R2 is independently hydrogen, fluorine, a straight-chain C1-20 alkyl group, a branched-chain C3-20 alkyl group, a monocyclic or polycyclic C3-20 cycloalkyl group, a straight-chain C2-20 alkenyl group, a branched-chain C3-20 alkenyl group, a monocyclic or polycyclic C3- The present invention is characterized in that the present invention is a cycloalkenyl group, a monocyclic or polycyclic C6-20 aryl group or a monocyclic or polycyclic C2-20 heteroaryl group, preferably hydrogen, a straight chain C1-6 alkyl group, a branched chain C3-6 alkyl group or a monocyclic or polycyclic C3-10 cycloalkyl group, each of which is substituted or unsubstituted, each R2 optionally includes one or more groups selected from -O-, -C(O)-, -C(O)-O- or -S- as part of its structure, and the R2 groups together optionally form a ring; and R3 is a straight chain C1-20 alkyl group, a branched chain C3-20 alkyl group, a monocyclic or polycyclic C3-2 The present invention is a C-20 cycloalkyl, a straight-chain C2-20 alkenyl, a branched-chain C3-20 alkenyl, a monocyclic or polycyclic C3-20 cycloalkenyl, a monocyclic or polycyclic C6-20 aryl or a monocyclic or polycyclic C2-20 heteroaryl, preferably a straight-chain C1-6 alkyl, a branched-chain C3-6 alkyl or a monocyclic or polycyclic C3-10 cycloalkyl, each of which is substituted or unsubstituted, R3 optionally includes one or more groups selected from -O-, -C(O)-, -C(O)-O- or -S- as part of its structure, and one R2 and R3 optionally form a ring together. Such monomers are usually vinyl aromatic, (meth)acrylate or norbornyl monomers. The total content of polymerized units comprising acid-decomposable groups forming carboxylic acid groups on the polymer is typically 10 to 100 mol%, more typically 10 to 90 mol% or 30 to 70 mol%, based on the total polymerized units of the polymer.

The polymer may further include monomers containing acid-labile groups as polymers, which decompose to form alcohol or fluoroalcohol groups on the polymer. Suitable such groups include, for example, acetal groups of the formula -COC(R2)2OR3- or carbonate groups of the formula -OC(O)O-, wherein R is as defined above. Such monomers are typically vinyl aromatic, (meth)acrylate or norbornyl monomers. If present in the polymer, the total content of polymerized units containing acid-decomposable groups that decompose to form alcohol or fluoroalcohol groups on the polymer is typically 10 to 90 mole %, more typically 30 to 70 mole %, based on the total polymerized units of the polymer.

The photoacid generator is a compound capable of generating an acid when irradiated with actinic rays or radiation. The photoacid generator can be selected from known compounds capable of generating an acid when irradiated with actinic rays or radiation, which are used as photoinitiators for cationic photopolymerization, photoinitiators for free radical photopolymerization, photodecolorizers for dyes, photofading agents, microresistors or the like, and mixtures thereof can be used. Examples of the photoacid generator include diazonium salts, phosphonium salts, codonium salts, iodonium salts, imidosulfonates, oximesulfonates, diazonium disulfonates, disulfonates and o-nitrobenzyl sulfonate.

Suitable photoacids include onium salts such as triphenylsarconium trifluoromethanesulfonate, (p-tert-butyloxyphenyl)diphenylsarconium trifluoromethanesulfonate, tris(p-tert-butyloxyphenyl)sarconium trifluoromethanesulfonate, triphenylsarconium p-toluenesulfonate; di-tert-butylphenyl iodonium perfluorobutanesulfonate and di-tert-butylphenyl iodonium camphorsulfonate. Non-ionic sulfonates and sulfonyl compounds are also known to act as photoacid generators, such as nitrobenzyl derivatives, such as 2-nitrobenzyl-p-toluenesulfonate, 2,6-dinitrobenzyl-p-toluenesulfonate, and 2,4-dinitrobenzyl-p-toluenesulfonate; sulfonates, such as 1,2,3-tris(methanesulfonyloxy)benzene, 1,2,3-tris(trifluoromethanesulfonyloxy)benzene, and 1,2,3-tris(p-toluenesulfonyloxy)benzene; diazomethane derivatives, such as bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, and bis(p-toluenesulfonyl)diazomethane. methane; glyoxime derivatives, such as bis-O-(p-toluenesulfonyl)-α-dimethylglyoxime and bis-O-(n-butanesulfonyl)-α-dimethylglyoxime; sulfonate derivatives of N-hydroxyimide compounds, such as N-hydroxybutanediimide methanesulfonate, N-hydroxybutanediimide trifluoromethanesulfonate; and halogen-containing tris(iodine) compounds, such as 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-tris(iodine) and 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-1,3,5-tris(iodine). Suitable non-polymeric photoacid generators are further described in U.S. Pat. No. 8,431,325 to Hashimoto et al. at column 37, lines 11-47 and columns 41-91. Other suitable sulfonate PAGs include sulfonated esters and sulfonyloxyketones, nitrobenzyl esters, mesitylene derivatives, benzoin tosylate, α-(p-toluenesulfonyloxy)-acetic acid tert-butylphenyl ester and α-(p-toluenesulfonyloxy)-acetic acid tert-butyl ester; as described in U.S. Pat. Nos. 4,189,323 and 8,431,325. PAGs that are onium salts typically contain anions having sulfonic acid groups or non-sulfonic acid type groups such as sulfonamidate groups, sulfonimidate groups, methide groups, or boric acid groups.

The resist composition may optionally include a variety of PAGs. The various PAGs may be polymeric, non-polymeric, or may include both polymeric and non-polymeric PAGs. Preferably, each of the various PAGs is non-polymeric. Preferably, when using a variety of PAGs, the first PAG includes a sulfonic acid group on the anion and the second PAG includes an anion that does not contain a sulfonic acid group, such an anion containing, for example, a sulfonamic acid ester group, a sulfonylimide ester group, a methide group, or a boric acid group as described above. In some embodiments, the composition of the first resist is similar to that of a positive tone developing (PTD) resist. In such embodiments, the first relief pattern may include a polymer made from the above-mentioned monomers, wherein any monomer including a reactive functional group is protected. Therefore, the PTD first resist may be organically soluble.

In other embodiments where the solubility-shifting agent is a crosslinking agent, the first resist is a negative resist. In such embodiments, the first resist may include a polymer made from the above-described monomers, wherein any monomer containing a reactive functional group is unprotected. Suitable reactive functional groups include, but are not limited to, alcohols, carboxylic acids, and amines. Exposure to the crosslinking agent causes the polymer to crosslink, rendering the polymer insoluble in the developer. The non-crosslinked areas can then be removed using an appropriate developer.

In one or more embodiments, the first resist is a negative resist. In such embodiments, the first relief pattern may include a polymer made from the above-mentioned monomers, wherein any monomers including reactive functional groups are not protected. Therefore, the first resist is soluble in organic solvents or aqueous alkaline solutions. The type of resist (i.e., positive or negative) can affect the final pattern placement. For example, if the resist is similar to a PTD photoresist and the selective adhesive contains an acid, the resist polymer above the feature will be deprotected and thus become soluble in aqueous alkaline solutions (e.g., TMAH), while the resist on the substrate will remain soluble in organic solvents. If the resist is similar to a negative photoresist and the selective adhesive contains a crosslinker, the resist polymer above the features will be crosslinked and insoluble, while the resist on the substrate will remain soluble.

In one or more embodiments, the first resist layer is stacked on the substrate such that it has a thickness of about 300 Å to about 3000 Å.

Next, at block 208 of method 200, the solubility shifting agent is activated. In embodiments where the solubility shifting agent is an acid, an acid generator, a base, or a base generator, activation of the solubility shifting agent includes diffusing the solubility shifting agent into the first resist to provide a solubility transition region of the first resist. The solubility transition region of the first resist may be determined by preferential adhesion of the selective adhesive. For example, a selective adhesive that preferentially adheres to existing patterned features, such as in selective patterned self-alignment, such as in method 200, may provide a solubility transition region of the first resist over the features. In one or more embodiments, the solubility transition zone of the first resist extends vertically from the surface of the selective adhesive coated on the topography to the surface of the first resist. In one or more embodiments, the solubility transition zone extends in an inclined direction. When the solubility transition zone extends in an inclined direction, it may be necessary to prevent the topography from merging together. To achieve this purpose, the thickness of the topography can be controlled to be sufficiently thin.

Diffusion of the solubility-shifting agent into the first resist is achieved by baking. Baking can be performed using a heating plate or an oven. The temperature and time of baking can depend on the properties of the second resist and the desired amount of solubility-shifting agent diffused into the second resist. Suitable conditions for baking can include a temperature in the range of about 50° C. to about 160° C. and a time in the range of about 30 to about 90 seconds.

The solubility transition region of the first resist may be determined by the preferential adhesion of the selective adhesive. For example, when the selective adhesive preferentially adheres to existing patterned features, such as in selective patterning self-alignment, such as in method 200, the solubility transition region of the first resist may be above the features. In one or more embodiments, the solubility transition region of the first resist may extend vertically to the surface of the first resist layer.

In embodiments where the solubility-shifting agent is a crosslinking agent, activation of the solubility-shifting agent includes initiating polymerization of the crosslinking agent into the first resist. Activation of the crosslinking agent may provide a crosslinking region of the first resist. The crosslinking region of the first resist may be determined by the preferential adhesion of the selective attachment agent. For example, when the selective attachment agent preferentially adheres to the topography of an existing pattern, such as in selective patterning self-alignment, the crosslinking region of the first resist may be above the topography.

Finally, at block 210 of method 200, the first resist is developed using a first developer. The first developer can be any developer commonly used in the art. The composition of the first developer can depend on the solubility characteristics of the first resist. For example, if the first resist is a positive-type developer, the specific developer can be a base, such as tetramethylammonium hydroxide. On the other hand, if the first resist is a negative-type developer, the specific developer can be a non-polar organic solvent, such as n-butyl acetate or 2-heptanone. In one or more embodiments, the solubility transition region or the crosslinking region is insoluble in the first developer. Thus, after developing the first resist, the solubility transition region or cross-linked region of the first resist may remain on the substrate. Thus, the method 200 may provide a substrate, as shown in FIG. 3D , comprising a pattern 305 of a solubility transition first resist, wherein the solubility transition first resist is directly on top of an existing pattern of topographic bodies 302.

Alternatively, in one or more embodiments, the solubility transition region becomes soluble in the first developer. In such embodiments, after the first resist is developed, the solubility transition region of the first resist is removed from the substrate. A coated substrate according to such embodiments is shown in FIG. 3E . In FIG. 3E , the substrate includes a pattern 305 of the first resist offset from a feature 302 coated with a selective adhesive 303. Such a pattern may be referred to as a counter-selective pattern because the feature of the resist remains above the base layer, which is not coated with the selective adhesive.

As noted above, in one or more embodiments, the method includes selectively forming a resist pattern that alternates with a topography in a base layer. Such methods, such as method 100, may be considered selective pattern formation because they form a first relief pattern based on the placement of a selective adhesive. However, methods that selectively form a pattern or first relief that alternates with an existing pattern of a topography may be referred to as selective anti-alignment because the two patterns are not aligned. A method 400 of selective anti-alignment pattern formation (e.g., the pattern shown in FIG. 1B ) according to the present disclosure is shown in FIG. 4 and discussed with reference thereto. Schematic diagrams of a coated substrate at various time points during the methods are shown in FIGS. 5A-D .

In method 400, an existing pattern is provided on a substrate at block 402. A coated substrate having an existing pattern is shown in FIG5A. In FIG5A, the existing pattern may include a topography 502 within a base layer 501. The topography and base layer are as previously described with respect to method 200.

Next, at block 404 of method 400, the substrate is coated with a selective adhesive. In one or more embodiments, the selective adhesive is coated on the entire substrate, except for the target area (i.e., the selective adhesive is coated on the entire base layer except for the topography). As described above, the selective adhesive can preferentially adhere to a material of an existing pattern. In one or more embodiments, in method 400, the selective adhesive adheres to the base layer of the existing pattern. Figure 5B shows a substrate including a selective adhesive 503, which is coated on the first layer of the existing pattern instead of the topography. The selective adhesive may adhere to the patterned topography at a ratio greater than 1: 1. As an example and not a limitation, the selective adhesive may adhere to the existing patterned base layer at a ratio of topography to base layer in the range of 1:2 to 1:10.

In one or more embodiments, the selective adhesive is a chemical functional group that can be further functionalized. Exemplary selective adhesives that are selective for dielectric materials relative to metals include, but are not limited to, silanes and alcohols. The specific selective adhesive applied to the existing pattern can depend on the specific chemical substances used in other components of method 200. For example, aminosilanes, halogen silanes (such as chlorosilanes, fluorosilanes, etc.) and alkoxysilanes (such as methoxysilanes, ethoxysilanes and other alkoxysilanes) can selectively or at least preferentially react with hydroxylated groups on the surface of dielectric materials compared to metal materials. Specific examples of suitable silanes include, but are not limited to, trichlorooctadecylsilane, octadecylchlorosilane, diethylaminotrimethylsilane, bis(dimethylamino)dimethylsilane, methoxysilane, ethoxysilane and other similar silanes, and combinations thereof. The reaction products of these reactions can be used to selectively coat exposed surfaces of dielectric materials. If a generally small amount of reaction does occur on the metal material, it can be removed, for example, by washing with water. The silane may include one or more other groups, such as linear alkane chains, branched alkane chains, other linear or branched organic chains, benzyl or other organic groups or various other known functional groups, in order to change the chemical properties of the silane and achieve the desired chemical properties. It is also known that compounds containing hydroxyl groups, such as alcohols and catechols, react with hydroxylated groups of dielectric materials. As another example, bifunctional, trifunctional, multifunctional electrophilic agents or combinations thereof can react with hydroxylated groups of materials (such as ILDs) and then react with functional groups of polymers to obtain activated reaction products. Selective attachment agents may also include polymers containing any of the functional groups capable of selective attachment to the aforementioned functional groups, wherein the polymer has functional groups along the main chain or as end groups and forms a polymer chain layer attached to the target material. Various other selective attachment agents known in the art may also potentially be used. It should be understood that these are only a few illustrative examples, and that other examples will be apparent to those who are familiar with the art and have the benefit of this disclosure.

In one or more embodiments, the selective attachment agent includes a solubility-shifting agent. The solubility-shifting agent can be a solubility-shifting agent as previously described with respect to method 200.

In some embodiments, after coating the substrate with the selective adhesive, the substrate is pre-treated. The pre-treatment may be baking at 50 to 150° C. for about 30 to 90 minutes.

In method 400, at block 406, a first resist is deposited on a substrate. The substrate coated with the first resist 504 is shown in FIG. 5C. In one or more embodiments, the first resist is as previously described with respect to method 200. In one or more embodiments, the first resist layer is superimposed on the substrate such that it has a thickness of about 300 Å to about 3000 Å.

At block 408 of method 400, the solubility shifter is activated. In embodiments where the solubility shifter is an acid, an acid generator, a base, or a base generator, activation of the solubility shifter includes diffusing the solubility shifter into the first resist to provide a solubility transition region of the first resist, as described above.

The solubility transition region of the first resist may be determined by the preferential adhesion of the selective adhesive. For example, when the selective adhesive preferentially adheres to the base layer of the existing pattern, such as in the anti-selective pattern self-alignment, such as in method 400, the solubility transition region of the first resist may be above the base layer. In one or more embodiments, the solubility transition region of the first resist may extend vertically to the surface of the first resist layer.

In the embodiment where the solubility shifting agent is a crosslinking agent, activation of the solubility shifting agent includes initiating polymerization of the crosslinking agent into the first resist. Activation of the crosslinking agent can provide a crosslinking region of the first resist. The crosslinking region of the first resist can be determined by the preferential adhesion of the selective adhesive. For example, when the selective adhesive preferentially adheres to the base layer of the existing pattern, such as in the anti-selective pattern self-alignment, the crosslinking region of the first resist can be above the base layer. The crosslinking region of the first resist can extend vertically from the base layer to the surface of the first resist.

Finally, in method 400, the first resist at block 410 is developed. The first resist may be developed using a first developer. The first developer may be selected based on the solubility characteristics of the first resist. In one or more embodiments, the solubility transition region or cross-linking region of the first resist is insoluble in the first developer. Therefore, after the first resist is developed, the solubility transition region or cross-linking region of the first resist may remain on the substrate. Therefore, method 400 may provide a substrate, as shown in FIG. 5D, comprising a pattern 505 of a solubility-transformed first resist, wherein the solubility-transformed first resist is offset from a topographical body 502 of an existing pattern.

In one or more embodiments, the inverse selective pattern self-alignment method can be modified so that the solubility transition region is soluble in the first developer. In such alternative embodiments, after development, the remaining modified first resist is positioned on top of the topography of the existing pattern, such as in selective pattern self-alignment.

Similarly, in one or more embodiments, the selective pattern self-alignment method can be modified so that the solubility transition region is soluble in the first developer. In such alternative embodiments, after development, the remaining modified first resist is offset from the topography of the existing pattern, such as in the reverse selective pattern self-alignment.

In one or more embodiments, the methods disclosed herein can be used to double pattern a feature volume on/adjacent to an existing pattern. Such methods can implement two selective pattern self-alignment methods, two anti-selective pattern self-alignment methods, or one selective pattern self-alignment method and one anti-selective pattern self-alignment method to achieve double patterning.

In an alternative embodiment, the topography is coated with a first selective attachment agent containing a first solubility shifter, and the base layer is coated with a second selective attachment agent containing a second solubility shifter. In some embodiments, the first solubility shifter comprises an acid or an acid generator and the second solubility shifter comprises a base or a base generator. The resist is then deposited on the base and the solubility shifters are activated simultaneously. The first solubility shifter diffuses from the top of the topography and the second solubility shifter diffuses from the top of the base layer. At the interface of the diffusion front, the solubility switching agents can interact with each other to prevent solubility switching of the resist in the lateral regions that are out of the vertical plane perpendicular to the substrate and located at the interface of the feature and the exposed substrate. This helps to limit the solubility switching to the region of the resist above the feature, thereby limiting the lateral growth of the opening and producing a generally straight-sided rather than a sloping profile.

Although only a few exemplary embodiments are described in detail above, those skilled in the art will readily appreciate that many modifications in the exemplary embodiments are possible without departing substantially from the present invention. Therefore, all such modifications are intended to be included within the scope of the present disclosure as defined in the following patent claims.

200,400: Method 202,204,206,208,210,402,404,406,408,410: Block 301,501: Base layer 302,502: Morphology 303,503: Selective adhesive 304,504: First resistor 305: Solubility transition of first resistor pattern, first resistor pattern 505: Solubility transition of first resistor pattern

FIG. 1A is a schematic diagram of a selective self-alignment pattern on a substrate according to one or more embodiments of the present disclosure.

FIG. 1B is a schematic diagram of a deselective self-alignment pattern on a substrate according to one or more embodiments of the present disclosure.

FIG. 2 is a process block diagram of a method according to one or more embodiments of the present disclosure.

3A-E are schematic illustrations of a coated substrate at various points in time according to a method according to one or more embodiments of the present disclosure.

FIG. 4 is a process block diagram of a method according to one or more embodiments of the present disclosure.

5A-D are schematic illustrations of a coated substrate at various points in time according to a method according to one or more embodiments of the present disclosure.

Claims (27)

A method of microfabrication, comprising: providing a substrate having an existing pattern, wherein the existing pattern comprises a morphology formed in a base layer, so that a top surface of the substrate has an uncovered morphology and the base layer is uncovered; depositing a selective adhesive on the substrate, wherein the selective adhesive comprises a solubility-changing agent; depositing a first resist on the substrate; activating the solubility-changing agent so that a portion of the first resist becomes insoluble in a first developer; and developing the first resist using the first developer so that the portion of the first resist that is insoluble in the first developer remains. The method of claim 1, wherein the selective adhesive adheres to the surface of the topographic bodies more than to the surface of the base layer. The method of claim 1 or 2, wherein the selective attachment agent comprises a phosphonic acid, a phosphonate, a phosphine, a sulfonic acid, a sulfinic acid, a carboxylic acid, a triazole, a thiol or a combination thereof. A method as claimed in claim 1 or 2, wherein the portion of the first resist that becomes insoluble in the first developer is above the topographic bodies. The method of claim 1, wherein the selective adhesive adheres to the surface of the base layer more than to the surface of the topographic bodies. The method of claim 1 or 5, wherein the selective adhesive comprises a silane, an alcohol or a combination thereof. The method of claim 1 or 5, wherein the portion of the first resist that becomes insoluble in the first developer is above the base layer. A method as claimed in claim 1, 2 or 5, wherein the solubility-shifting agent comprises an acid generator. As in the method of claim 8, wherein the acid generator does not contain fluorine. The method of claim 8, wherein the acid generator is selected from the group consisting of triphenylcoppersulfate, pyridine perfluorobutanesulfonate, 3-fluoropyridine perfluorobutanesulfonate, 4-tert-butylphenyltetramethylenecoppersulfonate, 4-tert-butylphenyltetramethylenecoppersulfonate 2-trifluoromethylbenzenesulfonate, 4-tert-butylphenyltetramethylenecoppersulfonate 4,4,5,5,6,6-hexafluorodihydro-4H-1,3,2-dithiazole

1,1,3,3-Tetraoxide and combinations thereof. A method as claimed in claim 1, 2 or 5, wherein the solubility-shifting agent comprises an acid. The method of claim 11, wherein the acid does not contain fluorine. The method of claim 11, wherein the acid is selected from the group consisting of trifluoromethanesulfonic acid, perfluoro-1-butanesulfonic acid, p-toluenesulfonic acid, 4-dodecylbenzenesulfonic acid, 2,4-dinitrobenzenesulfonic acid, 2-trifluoromethylbenzenesulfonic acid and combinations thereof. The method of claim 1, 2 or 5 further comprises pre-treating the substrate before depositing the first resist on the substrate. A method of microfabrication, the method comprising: providing a substrate having an existing pattern, wherein the existing pattern comprises a morphology formed in a base layer, so that a top surface of the substrate has an uncovered morphology and the base layer is uncovered; depositing a selective adhesive on the substrate, wherein the selective adhesive comprises a solubility-changing agent; depositing a first resist on the substrate; activating the solubility-changing agent so that a portion of the first resist becomes soluble in a first developer; and developing the first resist using the first developer so that the portion of the first resist soluble in the first developer is removed. The method of claim 15, wherein the selective adhesive adheres to the surface of the topographic bodies more than to the surface of the base layer. A method as claimed in claim 15 or 16, wherein the portion of the first resist that becomes insoluble in the first developer is above the topographic bodies. The method of claim 15 or 16, wherein the selective attachment agent comprises a phosphonic acid, a phosphonate, a phosphine, a sulfonic acid, a sulfinic acid, a carboxylic acid, a triazole, a thiol or a combination thereof. A method as claimed in claim 15 or 16, wherein the solubility-shifting agent comprises an acid generator. As in the method of claim 19, wherein the acid generator does not contain fluorine. The method of claim 19, wherein the acid generator is selected from the group consisting of triphenylcoppersulfate, pyridine perfluorobutanesulfonate, 3-fluoropyridine perfluorobutanesulfonate, 4-tert-butylphenyltetramethylenecoppersulfonate, 4-tert-butylphenyltetramethylenecoppersulfonate 2-trifluoromethylbenzenesulfonate, 4-tert-butylphenyltetramethylenecoppersulfonate 4,4,5,5,6,6-hexafluorodihydro-4H-1,3,2-dithiazole

1,1,3,3-Tetraoxide and combinations thereof. A method as claimed in claim 15 or 16, wherein the solubility-shifting agent comprises an acid. The method of claim 22, wherein the acid does not contain fluorine. The method of claim 22, wherein the acid is selected from the group consisting of trifluoromethanesulfonic acid, perfluoro-1-butanesulfonic acid, p-toluenesulfonic acid, 4-dodecylbenzenesulfonic acid, 2,4-dinitrobenzenesulfonic acid, 2-trifluoromethylbenzenesulfonic acid and combinations thereof. The method of claim 15 or 16 further comprises pre-treating the substrate before depositing the first resist on the substrate. A method of microfabrication, comprising: providing a substrate having an existing pattern, wherein the existing pattern comprises morphologies formed in a base layer, so that a top surface of the substrate has uncovered morphologies and the base layer is uncovered; Depositing a first selective adhesive on the substrate, wherein the first selective adhesive comprises a first solubility-changing agent, and wherein the first selective adhesive adheres to the surface of the morphologies more than to the surface of the base layer; depositing a second selective adhesive on the substrate A second selective adhesive, wherein the second selective adhesive comprises a second solubility-shifting agent, and wherein the second selective adhesive has a higher adhesion to the surface of the base layer than to the surfaces of the morphologies; depositing a first resist on the base; activating the first solubility-shifting agent and the second solubility-shifting agent so that a portion of the first resist becomes insoluble in a first developer; and developing the first resist using the first developer so that the portion of the first resist that is insoluble in the first developer remains. The method of claim 26, wherein the first solubility shifter comprises an acid or an acid generator and the second solubility shifter comprises a base or a base generator.