Semiconductor manufacturing method and resin composition

Abstract

This invention provides a semiconductor manufacturing method with a simplified process. [Solution] One aspect of the present invention is a method for manufacturing a semiconductor. The method for manufacturing a semiconductor includes the steps of forming a resin layer on a silicon-based substrate, patterning the resin layer, and performing ion implantation on the silicon-based substrate masked by the patterned resin layer, wherein the resin layer is obtained from a resin composition containing a polyhydroxyamide compound having the structural units of (1) below, a crosslinking agent, and a photoacid generator. TIFF2026101541000014.tif38170 {In formula (1), R 1 R is a divalent organic group. 2 It is a tetravalent organic group.

Description

[Technical Field]

[0001] This invention relates to a method for manufacturing semiconductors and a resin composition. [Background technology]

[0002] In the fabrication of semiconductor devices, an essential process is ion implantation, which involves implanting ions (impurities) into a semiconductor substrate.

[0003] Conventionally, the ion implantation process involves the following steps being performed sequentially (see, for example, Patent Document 1). • Process of forming a silicon oxide layer on a silicon substrate by CVD. • The process of applying a resist onto the silicon oxide layer described above. • A process of irradiating the resist with light using a photomask to pattern the resist. • Using the above resist as a mask, the silicon oxide layer is etched and the silicon oxide layer is patterned in a predetermined area. • A process of ion implantation into exposed areas of a silicon substrate using a silicon oxide layer as a mask. • Process of removing the silicon oxide layer

[0004] Conventional ion implantation processes require numerous steps, inevitably leading to increased manufacturing time and costs. Therefore, ion implantation processes using ion implantation masks made of photosensitive resin compositions are being investigated (for example, Patent Document 2). [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2006-324585 [Patent Document 2] Japanese Patent Publication No. 2017-097378 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Recent semiconductor devices demand even higher density and miniaturization. Therefore, masks used for ion implantation are required to be capable of forming fine patterns, and conventional photosensitive resin compositions have sometimes been insufficient.

[0007] In view of the above-mentioned problems, the present invention aims to provide a semiconductor manufacturing method with a simplified process that enables the formation of fine patterns, and a resin composition that can be used in said semiconductor manufacturing method. [Means for solving the problem]

[0008] One aspect of the present invention is a method for manufacturing a semiconductor. The method for manufacturing a semiconductor includes the steps of forming a resin layer on a silicon-based substrate, patterning the resin layer, and performing ion implantation on the silicon-based substrate masked by the patterned resin layer, wherein the resin layer is obtained from a resin composition containing a polyhydroxyamide compound having the structural units of (1) below, a crosslinking agent, and a photoacid generator. [ka] {In formula (1), R 1 R is a divalent organic group. 2 It is a tetravalent organic group. In the semiconductor manufacturing method according to the above embodiment, the resin composition may further contain an alcoholamine compound. The thickness of the resin layer may be 1.5 μm or more.

[0009] Another aspect of the present invention is a resin composition. This resin composition comprises a polyhydroxyamide compound having the structural units of (1) below, a crosslinking agent, and a photoacid generator, and is used for mask formation in ion implantation. [ka] {In formula (1), R 1is a divalent organic group, R 2 is a tetravalent organic group.}

Advantages of the Invention

[0010] According to the present invention, there is provided a technique related to a method for manufacturing a semiconductor with a simplified process, a manufacturing method capable of forming a fine pattern, and a resin composition that can be used in the method for manufacturing the semiconductor.

Brief Description of the Drawings

[0011] [Figure 1] Figs. 1(a) to (f) are process diagrams showing a method for manufacturing a semiconductor (ion implantation process). [Figure 2] Fig. 2 is a graph showing the temperature profile when heat curing is performed on the sample used in the examples. [Figure 3] Fig. 3 is a graph showing the simulation results of the implantation concentration distribution when ion implantation is performed on the resin composition used in the examples.

Modes for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described in detail. In this specification, the notation "a to b" in the description of a numerical range represents a to b unless otherwise specified.

[0013] (Method for Manufacturing a Semiconductor) The method for manufacturing a semiconductor according to the embodiment includes a step of forming a resin layer on a silicon-based substrate (hereinafter also referred to as a coating step), a step of patterning the resin layer (hereinafter also referred to as a patterning step), and a step of performing ion implantation on the silicon-based substrate masked by the patterned resin layer (hereinafter also referred to as an ion implantation step). Details of the resin layer will be described later.

[0014] In the following description, the semiconductor manufacturing method according to this embodiment will be explained using the case where the resin composition is a negative-type photosensitive resin composition as an example, but the method is also applicable when the resin composition is a positive-type photosensitive resin composition.

[0015] A specific example of the semiconductor manufacturing method according to the embodiment will be described with reference to Figure 1. Figures 1(a) to (f) are process diagrams showing the semiconductor manufacturing method (ion implantation process). <Coating process> First, as shown in Figure 1(a), a resin composition is applied to the silicon-based substrate 10 to a predetermined thickness, and dried as necessary to form a resin layer 20. Specific examples of the resin composition will be described later.

[0016] The silicon-based substrate 10 is appropriately selected depending on the semiconductor to be manufactured. For example, the silicon-based substrate 10 can be a Si substrate or a SiC substrate. In particular, a SiC substrate, which has excellent voltage resistance and heat resistance, can be suitably used for power semiconductor manufacturing.

[0017] The thickness of the resin layer 20 is, for example, 1.5 μm or more, 2.0 μm or more, 2.5 μm or more, or 3.0 μm or more, from the viewpoint of obtaining sufficient ion shielding ability in the ion implantation process. There is no particular upper limit to the thickness of the resin layer 20, and for example, from the viewpoint of forming a fine pattern, it is 10.0 μm or less, 8.0 μm or less, or 6.0 μm or less.

[0018] The method of applying the resin layer 20 is not particularly limited, and a spin coater, comma coater, blade coater, lip coater, rod coater, squeeze coater, reverse coater, transfer roll coater, gravure coater, or spray coater can be used.

[0019] If the resin composition contains a solvent, it is preferable to dry the resin composition after application. The drying method is not particularly limited and includes, for example, forced-air drying, heating drying using an oven or hot plate, and vacuum drying. When heating drying is performed, the conditions are, for example, a heating temperature of 70 to 140°C and a drying time of 1 to 30 minutes.

[0020] <Patterning process> Next, as shown in Figure 1(b), the resin layer 20 is patterned by photolithography to form a patterned resin layer 22 in a predetermined area (for example, a gate formation area) on the silicon substrate 10. Specifically, the resin layer 20 is irradiated with active energy rays (for example, UV light) using an exposure machine, and then the unexposed areas are developed with a dilute alkaline aqueous solution or an organic solvent to form the patterned resin layer 22.

[0021] The activated energy beam is irradiated onto the resin layer 20 via a photomask capable of forming the desired pattern. If patterning is not required, the photomask is not necessary. Alternatively, the pattern may be drawn directly with a laser using a direct writing device.

[0022] The wavelength of the activation energy ray used is one that can activate the photoacid generator, and for fine patterning, a maximum wavelength of 410 nm or less is preferable. The irradiation energy can be adjusted depending on the thickness of the formed resin layer, for example, 10 to 1500 mJ / cm². 2 This can be done. As the exposure light source, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, mercury short-arc lamps, KRF lasers, etc., can be used.

[0023] Post-exposure heating may be performed on the resin layer irradiated with active energy rays. Post-exposure heating improves the developability of the exposed area of ​​the resin layer 20, and thus can be expected to refine the patterned resin layer 22. The heating temperature in post-exposure heating can be 90 to 150°C, and the heating time can be 0.5 to 10 minutes. Heating can be performed by known methods such as a hot plate or a heating furnace.

[0024] Development is a process in which a resin layer irradiated with active energy rays is subjected to post-exposure heating as necessary, and then treated with a developing solution to obtain a patterned resin layer 22. Known methods can be used for development, such as the rotary spray method, the paddle method, and the immersion method with ultrasonic treatment.

[0025] Known developers can be used, such as aqueous solutions of inorganic alkalis like sodium hydroxide, sodium carbonate, sodium silicate, and aqueous ammonia; organic amines like ethylamine, diethylamine, triethylamine, and triethanolamine; and quaternary ammonium salts like tetramethylammonium hydroxide and tetrabutylammonium hydroxide. If necessary, water-soluble organic solvents or surfactants such as methanol, ethanol, and isopropyl alcohol can be added. Furthermore, organic solvents such as ketone solvents like cyclopentanone and cyclohexanone, ester solvents like propylene glycol monomethyl acetate and butyl acetate, and ether solvents like propylene glycol monomethyl ether can also be preferably used as developers.

[0026] After treatment with a developing solution, the resin layer can be washed with a rinsing solution as needed to obtain a patterned resin layer. The rinsing solution is not particularly limited and includes pure water, methanol, ethanol, isopropyl alcohol, etc. These can be used individually or in any combination in any ratio.

[0027] Furthermore, the patterned resin layer 22 after development may be subjected to further irradiation with active energy rays (for example, UV light) (hereinafter also referred to as a post-exposure process).

[0028] The post-exposure step involves irradiating the entire surface of the patterned resin layer 22 with active energy rays. Irradiation with active energy rays can be performed in the same manner as the irradiation during exposure described above, at a dose of 500-1500 mJ / cm². 2 The irradiation dose can be set to this value.

[0029] <Curing process> In the semiconductor manufacturing method of this embodiment, a curing step may be further performed after the patterning step, in which the patterned resin layer 22 is heat-cured. The curing step is a step of heat-curing the patterned resin layer 22 after the patterning step to obtain a patterned resin layer 24 made of a cured product (see Figure 1(c)). The heating temperature can be 150 to 200°C, and the heating time can be 1 to 120 minutes. Heating can be performed by known methods such as a hot plate or an inert oven, and it is preferable to heat under a nitrogen atmosphere. If the curing step is not performed, the patterned resin layer 24 made of a cured product in each subsequent step should be read as the patterned resin layer 22.

[0030] <Ion implantation process> Next, as shown in Figure 1(d), ion implantation is performed on the silicon substrate 10 using an ion implantation apparatus, with a patterned resin layer 24 made of cured material serving as a mask. The ion species used in ion implantation are appropriately selected according to the semiconductor to be manufactured. By implanting trivalent ion species such as boron and aluminum as impurities into the silicon substrate, a p-type semiconductor can be produced. On the other hand, by implanting pentavalent ion species such as arsenic and phosphorus as impurities into the silicon substrate, an n-type semiconductor can be produced.

[0031] As shown in Figure 1(e), by performing ion implantation using a patterned resin layer 24 made of cured material as a mask, ions are selectively implanted into the impurity region 30 of the silicon-based substrate 10 directly beneath the exposed area where the patterned resin layer 24 made of cured material is not formed. The conditions for ion implantation are not particularly limited, and well-known conditions (acceleration energy, implantation amount, beam current, implantation temperature, etc.) can be applied according to the required dose.

[0032] After ion implantation, ery ringing may be performed as needed. This allows for a more uniform concentration of impurities in the impurity region 30.

[0033] Next, as shown in Figure 1(f), the patterned resin layer 24 made of cured material is removed by O2 ashing or the like. Through these steps, a silicon-based substrate 10 can be obtained in which ions are selectively implanted in a predetermined region (impurity region 30).

[0034] The ion implantation process described above enables well formation and source / drain formation. After the ion implantation process described above, a MOS-FET can be fabricated, for example, by forming a gate using polysilicon. When manufacturing a MOS-FET, the impurity region 30 becomes the source region and the drain region.

[0035] In particular, by using a SiC substrate as the silicon-based substrate 10, it is possible to manufacture power semiconductors.

[0036] The ion implantation process in this embodiment simplifies the number of steps compared to conventional methods that use a silicon oxide layer as a mask. Therefore, it is possible to reduce the time and cost in semiconductor manufacturing.

[0037] Furthermore, the resin layer (mask) obtained using the resin composition described in detail later exhibits excellent ion implantation resistance and allows for the formation of fine patterns, thus enabling the manufacture of finer semiconductors.

[0038] (Resin composition) The resin composition according to the embodiment contains a polyhydroxyamide compound, a crosslinking agent, and a photoacid generator. As described above, the resin composition is used for mask formation in the ion implantation method. <Polyhydroxyamide compound> The polyhydroxyamide compound has a structural unit represented by the following formula (1).

[0039] [Chemical formula] {In formula (1), R 1 is a divalent organic group, and R 2 is a tetravalent organic group.}

[0040] R in formula (1) 1 is not particularly limited as long as it is a divalent organic group, and may be, for example, a divalent organic group containing an aromatic hydrocarbon group (arylene group), an aliphatic hydrocarbon group (alkylene group, cycloalkylene group), an ether group, a ketone group, an ester group, etc.

[0041] R in formula (1) 1 Preferably has an aromatic hydrocarbon group or an aliphatic hydrocarbon group among the above-mentioned divalent organic groups. Examples of the divalent organic group having an aromatic hydrocarbon group include divalent organic groups having structures such as a biphenyl skeleton, a diphenyl ether skeleton, a benzophenone skeleton, a diphenyl ethane skeleton, a diphenyl propane skeleton, a diphenyl hexafluoropropane skeleton, a diphenyl sulfone skeleton, and a benzene skeleton. Examples of the divalent organic group having an aliphatic hydrocarbon group include divalent organic groups having structures such as a cyclopropane skeleton, a cyclobutane skeleton, a cyclopentane skeleton, a cyclohexane skeleton, a cycloheptane skeleton, a cyclooctane skeleton, a cyclononane skeleton, a cyclodecane skeleton, a cycloundecane skeleton, a cyclododecane skeleton, and a dicyclopentadiene skeleton.

[0042] From the viewpoint of the resolution of the resin composition, etc., R 1The number of carbon atoms is preferably 4 to 30, and phenyl, biphenyl, diphenyl ether, and diphenylhexafluoropropane are preferred. In addition, the polyhydroxyamide compound contains R 1 It is also possible to include two or more of the groups exemplified above.

[0043] R in equation (1) 2 The tetravalent organic group is not particularly limited, but a tetravalent aromatic hydrocarbon group is preferred, for example. Examples of tetravalent aromatic hydrocarbon groups include tetravalent aromatic hydrocarbon groups having structures such as a biphenyl skeleton, diphenyl ether skeleton, diphenyl thioether skeleton, benzophenone skeleton, diphenylmethane skeleton, diphenylpropane skeleton, diphenylhexafluoropropane skeleton, diphenyl sulfoxide skeleton, diphenyl sulfone skeleton, benzene skeleton, and fluorene skeleton.

[0044] More specifically, the polyhydroxyamide compound preferably has the structural unit of the following formula (2).

[0045] [ka] In equation (2) above, Y is a methyl group or a trifluoromethyl group (CF3 group).

[0046] Polyhydroxyamide compounds may have alkali-soluble groups at their terminal ends. The alkali-soluble groups at the terminal ends are not particularly limited and include functional groups such as alcoholic hydroxyl groups, phenolic hydroxyl groups, acid anhydride groups, carboxyl groups, sulfonic acid groups, sulfonamide groups, and active methylene groups. From the viewpoint of solubility in developing solutions, it is preferable to have carboxyl groups or phenolic hydroxyl groups.

[0047] When the resin composition of this embodiment is a negative-type photosensitive resin composition, phenolic hydroxyl groups are particularly preferred among these alkali-soluble groups. When the polyhydroxyamide compound has phenolic hydroxyl groups at its termini, the solubility of the polyhydroxyamide compound in the developer can be improved. Furthermore, since phenolic hydroxyl groups are less reactive than carboxyl groups, excessive reaction with the crosslinking agent is suppressed, and the solubility of the unexposed areas in the developer can be maintained even when a PEB process is performed. As a result, resolution can be maintained, and it is presumed that a resin composition capable of forming finer and higher aspect ratio patterns can be provided.

[0048] Furthermore, the alkali-soluble groups contained at the ends of these polyhydroxyamide compounds may be present as residues of the monomers constituting the polyhydroxyamide compound, or as terminal structures introduced by a terminal encapsulant having alkali-soluble groups. Preferably, the alkali-soluble groups contained at the ends of the polyhydroxyamide compounds are present as terminal structures introduced by a terminal encapsulant having alkali-soluble groups.

[0049] Examples of end-capturing agents are not particularly limited and include compounds having one amino group and a hydroxyl group, such as aminophenol compounds, hydroxybenzylamine compounds, aminobenzyl alcohol compounds, and alcoholamine compounds; compounds having one carboxyl group and a hydroxyl group, such as hydroxy acids; acid anhydride compounds having a hydroxyl group, such as hydroxy acid anhydrides; compounds having an amino group and a carboxyl group, such as aminobenzoic acid and amino acids; and acid anhydride compounds such as phthalic anhydrides and 5-norbornene-2,3-dicarboxylic acid anhydrides.

[0050] Polyhydroxyamide compounds may contain structural units other than those shown in formulas (1) and (2) above.

[0051] The weight-average molecular weight (Mw) of the polyhydroxyamide compound is 2,000 to 20,000, preferably 2,000 to 15,000, more preferably 3,000 to 15,000, and even more preferably 4,000 to 10,000. This range allows for the formation of finer patterns with higher aspect ratios.

[0052] The number-average molecular weight (Mn) of the polyhydroxyamide compound is preferably 1,000 to 10,000, and more preferably 1,500 to 6,000.

[0053] The molecular weight dispersion (PDI) of the polyhydroxyamide compound is preferably 1.0 to 5.0, and more preferably 1.0 to 4.5.

[0054] When the weight-average molecular weight (Mw), number-average molecular weight (Mn), and molecular weight dispersion (PDI) of the polyhydroxyamide compound fall within a specified range, a favorable balance is achieved between solubility in the developer in the unexposed area and reaction with the crosslinking agent during exposure, resulting in a resin composition with superior resolution.

[0055] In this specification, the weight-average molecular weight and number-average molecular weight are measured by gel permeation chromatography (GPC) (GL7700, GL Sciences) and converted to standard polystyrene values. The specific measurement conditions are as follows: Column: TSKgelαM (manufactured by Tosoh Corporation) Column temperature: 40℃ Eluent composition: NMP solution containing 100 mmol / L H3PO4 (using an 85% aqueous solution of H3PO4 as the raw material) and 10 mmol / L LiBr. Eluent flow rate: 0.5mL / min Calibration standard reagent: Polystyrene Detector wavelengths: 260nm and 300nm Detector temperature: Room temperature (approximately 25°C) Baseline range during analysis: 15-40 minutes Molecular weight calculation range during analysis: 20-35 minutes Furthermore, in this specification, the molecular weight dispersibility (PDI) is calculated by the following formula. PDI = Mw / Mn

[0056] <Crosslinking agent> The crosslinking agent is not particularly limited and any known agent can be used, such as melamine compounds, guanamine compounds, triazine compounds, epoxy compounds, oxetane compounds, isocyanate compounds, and oxazoline compounds. The crosslinking agent is preferably a compound having at least one selected from the group consisting of methoxymethyl groups and methylol groups. These functional groups, using the acid generated from the photoacid generator described later as an active species, undergo a crosslinking reaction with phenolic hydroxyl groups and carboxyl groups contained in polyhydroxyamide compounds, etc., upon heating, thereby achieving negative-type photolithography (pattern formation) through exposure, PEB, and development. Furthermore, by further heating after pattern formation, the curing reaction of the resin composition proceeds, improving the heat resistance of the resin layer made of the cured product.

[0057] Furthermore, the crosslinking agent is preferably heterocyclic in order to improve the resolution of the resin composition and the heat resistance of the resin layer. The heterocyclic is not particularly limited and may contain one or more heteroatoms such as boron, nitrogen, oxygen, phosphorus, sulfur, antimony, arsenic, bismuth, selenium, silicon, tellurium, or tin, and may be a saturated or unsaturated ring of three, four, five, six, seven, or eight members. From the viewpoint of the resolution of the resin layer and the heat resistance of the resin layer, a heterocyclic containing nitrogen is preferred, and a heterocyclic containing multiple nitrogen atoms is more preferred.

[0058] Specifically, from the viewpoint of providing compounds having a triazine structure such as hexamethylolmelamine and hexamethoxymethylmelamine, tetramethylolbenzoguanamine, and tetramethoxymethylbenzoguanamine compositions, compounds having a guanamine structure such as triazine guanamine containing a triazine ring, compounds having a glycoluryl structure such as tetramethylol glycoluryl and tetramethoxyglycoluryl, and compounds having an imidazolidinone structure such as 1,3-bis(methoxymethyl)-2-imidazolidinone are more preferred. Of these, compounds having a triazine structure containing a triazine ring and compounds having a guanamine structure are particularly preferred from the viewpoint of being able to form a finer and higher aspect ratio pattern.

[0059] <Photoacid Generator> The photoacid generator is not particularly limited as long as it is a compound that generates acid upon irradiation with light such as ultraviolet or visible light. Examples include naphthoquinone diazide compounds, diarylsulfonium salts, triarylsulfonium salts, dialkylphenacylsulfonium salts, diaryliodonium salts, aryldiazonium salts, aromatic tetracarboxylic acid esters, aromatic sulfonic acid esters, nitrobenzyl esters, aromatic N-oxiamide sulfonates, aromatic N-oxiimide sulfonates, aromatic sulfamides, oxime sulfonate compounds, naphthalimide, and benzoquinone diazosulfonic acid esters. These can be used individually or in combination in any ratio. From the viewpoint of achieving better resolution, the photoacid generator is preferably an oxime sulfonate compound, and more preferably one containing the structure of formula (4) below.

[0060] [ka]

[0061] (In the formula, X is a hydrocarbon group or halogen atom, m is an integer from 0 to 3, R 3 (This refers to an organic group containing a hydrogen atom, a hydrocarbon group, a ketone group, or a halogen atom.) In formula (4) above, X is not particularly limited and can be, for example, a hydrocarbon group (e.g., alkyl group, alkenyl group, alkynyl group, aryl group, etc.) or a halogen atom. The hydrocarbon group may have substituents and can have a linear, branched, or cyclic structure. Linear or branched hydrocarbon groups having 1 to 4 carbon atoms are preferably used. A chlorine atom or a fluorine atom is preferably used as the halogen atom.

[0062] In equation (4) above, m represents an integer between 0 and 3, preferably 0 or 1. When m is 2 or 3, the multiple X values ​​may be the same or different.

[0063] R in equation (4) above 3 It is preferable that this be an organic group containing a hydrogen atom, a hydrocarbon group, a ketone group, or a halogen atom. The hydrocarbon group (e.g., alkyl group, alkenyl group, alkynyl group, aryl group, etc.) may be unsubstituted, or it may be substituted with a halogen atom.

[0064] The hydrocarbon group is preferably linear, branched, or cyclic with 1 to 20 carbon atoms, and more preferably linear, branched, or cyclic with 1 to 10 carbon atoms. The halogen atom may be a chlorine atom or a fluorine atom.

[0065] Examples of commercially available oximesulfonate compounds include Irgacure PAG103, Irgacure PAG108, Irgacure PAG121, and Irgacure PAG203, all manufactured by BASF.

[0066] <Alcoholamine compounds> The resin composition according to this embodiment may contain an alcoholamine compound. In particular, when the resin composition of this embodiment contains an alcoholamine compound, it is possible to suppress the diffusion of acid generated from the photoacid generator to the unexposed areas upon exposure, thereby improving resolution and preventing the formation of development residue in the unexposed areas after development.

[0067] Alcoholamine compounds are compounds having an alcoholic hydroxyl group and an amine skeleton, and the amine skeleton can be a primary amine skeleton, a secondary amine skeleton, or a tertiary amine skeleton. Alcoholamine compounds are not particularly limited, and examples include diethanolamine, triethanolamine, tris(2-methoxy)amine, bis(2-methoxy)amine, tris(2-ethoxy)amine, bis(2-ethoxy)amine, N-methyldiethanolamine, N-ethyldiethanolamine, N,N-dimethylethanolamine, etc. These can be used individually or in combination in any ratio. Of these, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, and N,N-dimethylethanolamine are more preferred.

[0068] <Solvent> The resin composition of this embodiment may contain a solvent. The solvent is not particularly limited and examples include ethers, esters, glycol esters, ketones, lactones, lactams, sulfoxides, tetramethylurea, dimethyl sulfone, pyridine, and the like.

[0069] Examples of ethers include 2-methoxy-1-methylethyl acetate (PGMEA), ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, propylene glycol dimethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, and dipropylene glycol monoethyl ether.

[0070] Examples of esters include ethyl acetate, butyl acetate, ethyl lactate, methyl 3-methoxypropionate, methyl 2-methoxypropionate, ethyl 3-methoxypropionate, ethyl 2-methoxypropionate, ethyl 3-ethoxypropionate, and ethyl 2-ethoxypropionate.

[0071] Ketones include methyl ethyl ketone; methyl isobutyl ketone (4-methyl-2-pentanone); 2-heptanone; Cycloalkanones, which are monoketones such as cyclopropanone, cyclobutanone, cyclopentanone, cyclohexanone, methylcyclohexanone, cycloheptanone, cyclooctanone, 2-norbornone, 2-methylcyclohexanone, 4-methylcyclohexanone, 3-methylcyclohexanone, and 2,2-dimethylcyclopentanone; Cycloalkanones of diketones such as 1,3-cyclopentanedione, 3-methyl-1,2-cyclopentanedione, 1,2-cyclohexanedione, 1,3-cyclohexanedione, 1,4-cyclohexanedione, and 2-methyl-1,3-cyclopentanedione; Cycloalkenones such as 4-methyl-2-cyclopentenone, 2-cyclohexenone, 2-cyclopenten-1-one, and 2-cyclohexen-1-one; Examples include cyclic ketones with a heterocyclic skeleton, such as 2-azetidinone, 4,5-dihydro-3(2H)-thiophenone, 4-oxotiane, and dihydrolevogluconocene.

[0072] Examples of glycol esters include carbitol acetate, ethyl cellosolve acetate, and ethylene glycol monoethyl ether acetate.

[0073] Examples of lactones include γ-butyrolactone, examples of lactams include N-methylpyrrolidone and N-methylcaprolactam, and examples of sulfoxides include dimethyl sulfoxide and hexamethyl sulfoxide.

[0074] These solvents can be used individually or in combination in any ratio. Among these solvents, lactones or cyclic ketones are preferred from the viewpoint of excellent affinity with each component in the resin composition, and γ-butyrolactone or cyclopentanone are preferred. Furthermore, from the viewpoint of excellent solvent removal during drying of the resin composition and suitability for the edge rinsing process in semiconductor manufacturing, cyclic ketones are preferred, monoketones such as cycloalkanones are more preferred, and cyclopropanone, cyclobutanone, cyclopentanone, cyclohexanone, methylcyclohexanone, cycloheptanone, cyclooctanone, 2-norbornanone, 2-methylcyclohexanone, 4-methylcyclohexanone, 3-methylcyclohexanone, and 2,2-dimethylcyclopentanone are even more preferred, and cyclopentanone is particularly preferred.

[0075] <Other ingredients> The resin composition of this embodiment may contain other components as long as they do not impair the effects of the disclosed technology. Other components may include known components that can be included in a resin composition, such as fillers, adhesives, surfactants, plasticizers, thermoacid generators, sensitizers, leveling agents, colorants, fibers, fine particles, and the like.

[0076] The surfactant is not particularly limited and examples include fluorine-based surfactants and silicone-based surfactants. Examples of commercially available fluorine-based surfactants include DIC's "MegaFac" series (e.g., MegaFac F-281, F-477, F-553, F-554, F-555, F-556, F-557, F-558, F-559, F-560, F-561, F-563, F-569, etc.). Examples of commercially available silicone-based surfactants include the surface modifier series from BICK CHEMI Corporation (e.g., BYK-302, BYK-307, BYK-310, BYK-322, BYK-323, BYK-326, BYK-331, BYK-332, BYK-333, BYK-348, BYK-349, BYK-377, BYK-378, BYK-3455, BYK-3760, etc.). These may be used individually or in combination of two or more types.

[0077] (Preparation of resin composition) The resin composition of this embodiment can be obtained by mixing a polyhydroxyamide compound, a crosslinking agent, a photoacid generator, and any other component, including an alcoholamine compound. The mixing of each component can be carried out under heating as needed. <Polyhydroxyamide compounds> The polyhydroxyamide compound content can be 50 to 80% by mass, where the total mass of solids in the resin composition is 100% by mass. Here, the mass of solids as used herein refers to the mass of the residue after all volatile components have been completely evaporated. <Crosslinking agent> The crosslinking agent content can be 5 to 80 parts by mass, based on a total mass of 100 parts by mass of the solid content of the polyhydroxyamide compound in the resin composition. Furthermore, if the crosslinking agent contains methoxymethyl groups and / or methylol groups, the ratio of the number of methoxymethyl groups and / or methylol groups in the crosslinking agent to the number of phenolic hydroxyl groups in the resin composition (methoxymethyl groups and / or methylol groups: phenolic hydroxyl groups) can be set to 120:100 to 200:100. Such a ratio can improve the resolution and heat resistance of the resin composition after heat curing. <Photoacid Generator> The amount of photoacid generator can be 0.1 to 20 parts by mass, and preferably 0.5 to 10 parts by mass, when the total mass of the solid content of the polyhydroxyamide compound in the resin composition is 100 parts by mass.

[0078] <Alcoholamine compounds> When adding an alcoholamine compound, the content can be 0.01 to 1.0 parts by mass, preferably 0.05 to 0.50 parts by mass, based on the total mass of the solid content of the polyhydroxyamide compound in the resin composition being 100 parts by mass. This range makes it easier to suppress the generation of development residue in the unexposed areas after developing the resin composition.

[0079] The embodiments of the present invention have been described above, but these are merely examples, and various other configurations can also be adopted. [Examples]

[0080] The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited thereto. <Polyhydroxyamide compounds> A polyhydroxyamide compound represented by the following formula was synthesized. Specifically, in a 120 mL vial (room temperature) equipped with a stirrer and thermometer, 16.3 g (44.5 mmol) of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (6FAP), 1.80 g (22.0 mmol) of 3-aminophenol, and 70 g of N-methylpyrrolidone (NMP) were stirred and dissolved for 15 minutes. Then, the vial was immersed in an ice bath, and while maintaining the temperature inside the vial at 0-5°C, 16.4 g (55.5 mmol) of 4,4'-oxybis(benzoyl chloride) (DEDC) was added as a solid over 10 minutes, and the mixture was stirred in the ice bath for 30 minutes. After stirring at room temperature for 18 hours, the solution was added to a large amount of deionized water, and the precipitate was collected. The obtained solid was dissolved in 135 g of ethyl acetate. 18 g of anion exchange resin (Organo Amberlist B-20) was added to this mixture and vigorously stirred for 1 hour. After concentrating the stirred solution, it was added to a large amount of deionized water and the precipitate was collected. After collecting the precipitated solid, it was dried under reduced pressure to obtain a polyhydroxyamide compound (Mn: 3,200, Mw: 9,500).

[0081] [ka]

[0082] (B-1)MW-390 (hexamethoxymethylmelamine compound manufactured by Nippon Carbide Industries Co., Ltd.) was used (see formula below).

[0083] [ka] PAG-103 (an oxime sulfonate compound manufactured by BASF) was used as the photoacid generator (see formula below).

[0084] [ka] <Alcoholamine compounds> Triethanolamine (TEA) was used as the alcoholamine compound (see formula below).

[0085] [ka] Cyclopentanone (manufactured by Tokyo Chemical Industry Co., Ltd.) was used as the solvent. <Preparation of resin composition> The above-mentioned components were blended in the amounts specified below, and the resin composition varnish was obtained by adding a solvent to dissolve and adjust the mixture so that the concentration of non-volatile components in the varnish reached 30%. Polyhydroxyamide compound: 100 parts by mass (solids) Crosslinking agent: 40 parts by mass (solid content) Photoacid generator: 5 parts by mass (solid content) Basic compound: 0.15 parts by mass (solid content)

[0086] (Ion implantation resistance evaluation) <Sample preparation> Samples for ion implantation resistance evaluation were prepared using the varnish of the obtained resin composition.

[0087] A resin composition varnish was applied to a silicon wafer using a spin coater to achieve a dry film thickness of 3 μm. The resin layer was then dried on a hot plate at 90°C for 3 minutes. An i-line stepper (FPA-3030i5+ (Canon)) was used to expose this resin layer with a test pattern having an L / S ratio of 1 / 1 μm. Post-exposure heating (PEB) was performed on a hot plate for 60 seconds. The PEB heating temperature was 120°C. Subsequently, development was performed using a 2.38 mass% TMAH aqueous solution for 60 seconds, followed by rinsing with ultrapure water for 30 seconds to obtain a patterned resin layer. The silicon wafer with the patterned resin layer was cut into 3 cm × 3 cm sections.

[0088] (Sample 1) The extracted samples were exposed to a contact exposure system (UVE-251S + EL-100 (manufactured by Sanei Electric Works Co., Ltd.)) at a concentration of 1000 mJ / cm². 2 After post-exposure under these conditions, the material was cured by heating. The temperature profile during heating is shown in Figure 2.

[0089] (Sample 2) The extracted samples were exposed to a contact exposure system (UVE-251S + EL-100 (manufactured by Sanei Electric Works Co., Ltd.)) at a concentration of 1000 mJ / cm². 2 Post-exposure was performed under these conditions (heat curing was not performed).

[0090] (Sample 3) The cut samples were cured by heating (no post-exposure was performed). The temperature profile during heating is shown in Figure 2.

[0091] (Sample 4) The cut samples were left as they were, without post-exposure or heat curing. <Ion implantation> Ion implantation was performed on each sample under the same conditions described below. Equipment used: Medium-current ion implanter (400 keV) Implanted ion species: Al Acceleration energy: 350.1 keV Injection amount: 1.000×10 15 / cm 2 Beam current: 2.55mA Injection time: 1142.6 seconds Tilt angle: 0° Temperature: Room temperature (120-130°C during the injection process) <Shape observation> Cross-sectional observations were performed on each sample before and after ion implantation using a scanning electron microscope (SEM). The shrinkage rate (%: percentage decrease from the value before ion implantation) of the pattern's film thickness, top line width, and bottom line width was calculated before and after ion implantation. The results are shown in Table 1.

[0092] [Table 1]

[0093] Table 1 shows that the resin composition of this embodiment can form a finely patterned resin composition layer, and its shape does not change easily before and after ion implantation, thus enabling the formation of fine patterns in semiconductors.

[0094] (Ion implantation test simulation) The implantation concentration distribution when ions are implanted into a resist was calculated using simulation software (SRIM2008). The conditions of the resin composition used in the simulation are shown below. The molar ratio of C:H was estimated from the composition of the resin composition used in the examples. C:H = 0.59:0.41 (molar ratio) Density: 1.05g / cm 3 Film thickness: 3.5 μm The results obtained are shown in Figure 3. As shown in Figure 3, it was confirmed that if the film thickness is approximately 1.5 μm or more, ions can be blocked and the mask can be effectively used as an ion implantation mask. [Industrial applicability]

[0095] The semiconductor manufacturing method described herein is useful in the semiconductor manufacturing field because it can simplify the ion implantation process. [Explanation of symbols]

[0096] 10 Silicon-based substrate, 20 Resin layer, 22 Patterned resin layer, 24 Patterned resin layer consisting of cured material, 30 Impurity region

Claims

1. A process of forming a resin layer on a silicon-based substrate, The process of patterning the aforementioned resin layer, The process includes performing ion implantation on the silicon-based substrate masked with a patterned resin layer, A method for manufacturing a semiconductor, wherein the resin layer is a resin layer obtained from a resin composition containing a polyhydroxyamide compound having the structural units of (1) below, a crosslinking agent, and a photoacid generator. 【Chemistry 1】 {In formula (1), R １ R is a divalent organic group. ２ It is a tetravalent organic group.

2. The method for producing a semiconductor according to claim 1, wherein the resin composition further comprises an alcoholamine compound.

3. The method for manufacturing a semiconductor according to claim 1 or 2, wherein the thickness of the resin layer is 1.5 μm or more.

4. The compound comprises a polyhydroxyamide compound having the structural unit described in (1) below, a crosslinking agent, and a photoacid generator, A resin composition used for mask formation in ion implantation. 【Chemistry 2】 {In formula (1), R １ R is a divalent organic group. ２ It is a tetravalent organic group.

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