JP4548318B2 - Positive photosensitive resin composition and semiconductor device using the positive photosensitive resin composition - Google Patents

Description

  The present invention relates to a positive photosensitive resin composition and a semiconductor device using the positive photosensitive resin composition.

  Conventionally, polybenzoxazole resins and polyimide resins having excellent heat resistance and excellent electrical and mechanical properties have been used for surface protective films and interlayer insulating films of semiconductor elements.

Here, in order to simplify the process when a polybenzoxazole resin or a polyimide resin is used, a positive photosensitive resin composition in which a diazoquinone compound of a photosensitive material is combined with these resins is also used (Patent Document 1). ).
JP-A-1-46862

  The prior art described in the above literature has room for improvement in the following points.

  The surface protective film and the interlayer insulating film of the conventional semiconductor element have a sufficiently high elastic modulus. Therefore, when a semiconductor package is manufactured with the semiconductor sealing resin, the filler contained in the semiconductor sealing resin has a surface. There has been a problem that the surface of the protective film and the interlayer insulating film is pierced, and wrinkles and cracks are generated on the film surface by the reflow process, thereby reducing the yield of the semiconductor package. In addition, there is a problem that even if a high elastic modulus is maintained, the solubility in a solvent is low, so that development with an alkaline developer cannot be performed satisfactorily.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a positive photosensitive resin composition capable of realizing a relatively high yield with a high elastic modulus and capable of alkali developability. It is in.

Such an object is achieved by the present invention described in the following [1] to [9].
[1]
(A) a polyamide resin represented by the general formula (1), and
(B) a photosensitive diazoquinone compound,
A positive photosensitive resin composition comprising:

(In the formula, n is an integer of 1 or more. X and Y are organic groups, and at least one Y ₁ is included in Y included in the polyamide resin.)

(In the formula, R ₁ and R ₂ are organic groups and may be the same or different. M and n are integers of 1 or more. They may be the same or different.)
[2]
The positive photosensitive resin composition according to [1], wherein Y ₁ is represented by the following formula.

(R ₃ and R ₄ are hydrogen or a hydrocarbon group and may be the same or different.)
[3]
The positive photosensitive resin composition according to [1] or [2], wherein a proportion of Y ₁ contained in the polyamide resin is 50 to 100%.
[4]
Furthermore, the positive photosensitive resin composition in any one of [1] thru | or [3] containing the compound which has (C) phenolic hydroxyl group.
[5]
The positive photosensitive resin composition according to [4], wherein the compound (C) having a phenolic hydroxyl group has a structure represented by the following formula:

(Wherein R ₅ and R _{6 each} represent a halogen atom, an alkyl group, an alkoxy group, an alkyl ester group cycloalkyl group or a cycloalkoxy group. R ₅ and R ₆ may be the same or different. M , N is an integer of 0 to 5. p and q are integers of 0 to 3 and p + q ≧ 2.R ₇ is a single bond, a methylene group, an alkylene group, an oxygen atom, a carbonyl group, a carbonyl ether group. , Represents a sulfur atom, a sulfonyl group, or an azo group.)
[6]
A step of applying the positive photosensitive resin composition according to any one of [1] to [5] onto a substrate to form a composition layer;
Irradiating active energy rays to a desired portion of the composition layer, and then contacting with a developer to form a pattern; and
Heating the composition layer;
A pattern forming method comprising:
[7]
A semiconductor substrate, a semiconductor element provided on the semiconductor substrate, and an insulating film provided on the semiconductor element;
The semiconductor device, wherein the insulating film is a film formed from the positive photosensitive resin composition according to any one of [1] to [5].
[8]
A display element substrate, an insulating film covering the surface, and a display element provided on the display element substrate;
The light-emitting device, wherein the insulating film is a film formed from the positive photosensitive resin composition according to any one of [1] to [5].
[9]
A method of manufacturing a semiconductor device comprising a semiconductor chip and a protective film covering the surface thereof,
Applying a positive photosensitive resin composition on the semiconductor chip to form a resin layer;
Irradiating an active energy ray to a desired portion of the resin layer; and
A step of bringing the developer into contact with the resin layer after irradiation with active energy rays, and then forming the protective film by heating the resin layer;
Including
The method of manufacturing a semiconductor device, wherein the positive photosensitive resin composition is the positive photosensitive resin composition according to any one of [1] to [5].

  According to the positive photosensitive resin composition of the present invention, there is provided a positive photosensitive resin composition which can realize a relatively high yield with a high elastic modulus and can be developed with an alkali developer.

  The present invention relates to a positive photosensitive resin composition containing (A) a polyamide resin represented by the general formula (1) and (B) a photosensitive diazoquinone compound. The following is an example, and the present invention is not limited to the following. Hereinafter, each component of the positive photosensitive resin composition of the present invention will be described in detail.

The polyamide resin represented by the general formula (1) in the present invention is characterized in that it contains at least one Y ₁ out of Y contained in the polyamide resin. Y ₁ has an ester structure sandwiched between aromatic rings, and the presence of this structure in the polyamide of the present invention improves the crystallinity of the polyamide resin, and a positive photosensitive resin composition using the same It is possible to improve the film surface elastic modulus of the surface protective film and the interlayer insulating film manufactured from the product.

Y in the general formula (1) can take the following organic groups in addition to Y ₁ .
For example, the following formula is exemplified.

(Wherein A: —CH ₂ —, —C (CH ₃ ) ₂ —, —O—, —S—, —SO ₂ —, —CO—, —NHCO—, —C (CF ₃ ) ₂ —, or R ₁₀ represents one selected from an alkyl group and a halogen atom, and may be the same or different, and is a positive number r = 0 to 2.)

However, it is not limited to these. Among these, more preferable are:

(R ₁₁ represents one selected from an alkyl group and a halogen atom, and may be the same or different. R is an integer of 0 to 2.)

Two or more types may be used.

In the present invention, among the Y included in the polyamide resin of the general formula (1), the ratio of the Y ₁ is occupied by is preferably 50-100%. More preferably, it is 70 to 100%. When the said ratio is more than a lower limit, there exists a merit that a high elasticity modulus and solvent solubility can be maintained.

In the polyamide resin represented by the general formula (1) in the present invention, X contained in the polyamide resin can have the following organic groups.
For example, the following formula is exemplified.

(In the formula, A represents —CH ₂ —, —C (CH ₃ ) ₂ —, —O—, —S—, —SO ₂ —, —CO—, —NHCO—, —C (CF ₃ ) ₂ —, —COO— or a single bond, R ₁₂ represents one selected from an alkyl group, an alkyl ester group, and a halogen atom, and may be the same or different, and is a positive number of r = 0 to 2. R ₁₃ represents one selected from a hydrogen atom, an alkyl group, an alkyl ester group, and a halogen atom.)
Among these, preferred are those represented by the following formula. These may be used alone or in combination of two or more.

(R ₉ represents one selected from an alkyl group, an alkyl ester group, and a halogen atom, and each may be the same or different. R is an integer of 0 to 2.)
In the present invention, it is desirable to seal the end from the viewpoint of storage stability. For sealing, a derivative having an aliphatic group or a cyclic compound group having at least one alkenyl group or alkynyl group can be introduced as an acid derivative or an amine derivative at the end of the polyamide represented by the general formula (1). Specifically, for example, a compound selected from diamine or bis (aminophenol) having a structure of X, 2,4-diaminophenol, and the like, and a tetracarboxylic acid anhydride, trimellitic acid anhydride, dicarboxylic acid having a structure of Y After synthesizing a polyamide resin having a structure represented by the general formula (1) obtained by reacting with a compound selected from acid or dicarboxylic acid dichloride, dicarboxylic acid derivative, hydroxydicarboxylic acid, hydroxydicarboxylic acid derivative, etc. It is preferable to cap the terminal amino group contained in the polyamide resin as an amide using an acid anhydride or acid derivative containing an aliphatic group or cyclic compound group having at least one alkenyl group or alkynyl group. Examples of the group derived from an acid anhydride or acid derivative containing an aliphatic group or cyclic compound group having at least one alkenyl group or alkynyl group after reacting with an amino group include:

However, it is not limited to these.
Among these, particularly preferred are:

  Two or more types may be used. The method is not limited to this method, and the terminal acid contained in the polyamide resin is capped as an amide using an amine derivative containing an aliphatic group or a cyclic compound group having at least one alkenyl group or alkynyl group. You can also

  When this polyamide resin is heated at about 250 to 400 ° C., it is dehydrated and closed, and a heat-resistant resin is obtained in the form of polyimide resin, polybenzoxazole resin, or copolymerization of both.

  The photosensitive diazoquinone compound (B) used in the present invention is a compound having a 1,2-benzoquinonediazide or 1,2-naphthoquinonediazide structure, and is known from US Pat. It is a substance. For example, the following are mentioned.

In the formula, Q is selected from a hydrogen atom, formula (5), and formula (6). Here, at least one of Q of each compound is represented by formula (5) or formula (6).

  Among these, an ester of a phenol compound and 1,2-naphthoquinone-2-diazide-5-sulfonic acid or 1,2-naphthoquinone-2-diazide-4-sulfonic acid is particularly preferable. Specific examples thereof include the following formula. These may be used alone or in combination of two or more.

In the formula, Q is selected from a hydrogen atom, formula (5), and formula (6). Here, at least one of Q of each compound is represented by formula (5) or formula (6).

  A preferred addition amount of the photosensitive diazoquinone compound (B) used in the present invention is 1 to 50 parts by weight with respect to 100 parts by weight of the resin. If the amount is less than 1 part by weight, a good pattern cannot be obtained, and if it exceeds 50 parts by weight, the sensitivity is greatly reduced.

  Furthermore, in the present invention, it is preferable to use (C) a compound having a phenolic hydroxyl group in combination so that high-sensitivity and patterning can be performed with high resolution without developing residue (scum) during development. As for the compounding quantity of the compound which has a phenolic hydroxyl group, 1-30 weight part is preferable with respect to 100 weight part of resin. The compound having a phenolic hydroxyl group is represented by the general formula (4). Specific examples of the general formula (4) include the following, but are not limited thereto.

Of these, preferably

It is chosen from.

  The resin composition and the positive photosensitive resin composition in the present invention may contain additives such as a leveling agent and a silane coupling agent as necessary.

  In the present invention, these components are dissolved in a solvent and used in the form of a varnish. Solvents include N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol Monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl-1,3-butylene glycol acetate, 1,3-butylene glycol-3-monomethyl ether, methyl pyruvate, ethyl pyruvate, methyl-3-methoxypropio And the like, and may be used alone or in combination. However, among the above, regarding the amine-based solvent (for example, N-methyl-2-pyrrolidone, etc.), the usage ratio and the like are limited in the usage environment of the semiconductor process.

  In the method of using the positive photosensitive resin composition of the present invention, first, the composition is applied to a suitable support such as a silicon wafer, a ceramic substrate, an aluminum substrate and the like. In the case of a semiconductor device, the coating amount is applied so that the final film thickness after curing is 0.1 to 50 μm. When the film thickness is less than the lower limit, it is difficult to sufficiently exert the function as a surface protective film of the semiconductor element, and when the film thickness exceeds the upper limit, it is difficult to obtain a fine processed pattern. Examples of the coating method include spin coating using a spinner, spray coating using a spray coater, dipping, printing, roll coating, and the like. Next, after prebaking at 60 to 130 ° C. to dry the coating film, actinic radiation is applied to the desired pattern shape. As the actinic radiation, X-rays, electron beams, ultraviolet rays, visible rays and the like can be used, but those having a wavelength of 200 to 500 nm are preferable.

  Next, a relief pattern is obtained by dissolving and removing the irradiated portion with a developer. As the developer, inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, diethylamine, di-n Secondary amines such as propylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, quaternary ammonium such as tetramethylammonium hydroxide and tetraethylammonium hydroxide An aqueous solution of an alkali such as a salt and an aqueous solution to which an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant is added can be preferably used. As a developing method, methods such as spraying, paddle, dipping, and ultrasonic waves are possible.

  Next, the relief pattern formed by development is rinsed. Distilled water is used as the rinse liquid. Next, heat treatment is performed to form an oxazole ring and / or an imide ring, thereby obtaining a final pattern rich in heat resistance.

  The photosensitive resin composition according to the present invention is useful not only for semiconductor applications but also as interlayer insulation for multilayer circuits, cover coats for flexible copper-clad plates, solder resist films and liquid crystal alignment films, interlayer insulation films for elements in display elements, etc. It is.

  Examples of specific uses for semiconductors include a passivation film obtained by forming the above-described photosensitive resin composition film on a semiconductor element, and a photosensitive resin composition described above on a passivation film formed on a semiconductor element. Examples thereof include a buffer coat film formed by forming a physical film, and an interlayer insulating film formed by forming the above-described photosensitive resin composition film on a circuit formed on a semiconductor element.

  Among them, as one application example in which the photosensitive resin composition of the present invention is used in a semiconductor device, application to a semiconductor device having bumps will be described with reference to the drawings. FIG. 1 is an enlarged cross-sectional view of a pad portion of a semiconductor device having a bump according to the present invention. As shown in FIG. 1, a passivation film 3 is formed on an input / output Al pad 2 in a silicon wafer 1, and a via hole is formed in the passivation film 3. Further, a positive photosensitive resin (buffer coat film) 4 is formed thereon, and a metal (Cr, Ti, etc.) film 5 is formed so as to be connected to the Al pad 2, and the metal film 5 is formed of solder bumps. 9 is etched to insulate between the pads. Barrier metal 8 and solder bumps 9 are formed on the insulated pads.

  Examples of display device applications include TFT interlayer insulating films, TFT element flattening films, color filter flattening films, protrusions for MVA liquid crystal display devices, and cathode partitions for organic EL elements. The usage method is based on forming the photosensitive resin composition layer patterned on the board | substrate which formed the display body element and the color filter by said method according to a semiconductor use. High transparency is required for display device applications, especially interlayer insulation films and planarization films, but by introducing a post-exposure process before curing the photosensitive resin composition layer, it is excellent in transparency. A resin layer can be obtained, which is more preferable in practical use.

Hereinafter, the present invention will be described specifically by way of examples.
Example 1
[Synthesis of polyamide resin]
1,3-dihydro-1,3-dioxo-5-isobenzofurancarboxylic acid-1,4-phenylene ester 7.33 g (0.016 mol) and 1,3-phenylenediamine 1.30 g (0.012 mol) And 1,4-phenylenediamine (0.87 g, 0.008 mol) were placed in a four-necked separable flask equipped with a thermometer, stirrer, raw material inlet, and dry nitrogen gas inlet tube, and N-methyl-2- 57.0 g of pyrrolidone was added and dissolved. Thereafter, the mixture was reacted at 75 ° C. for 12 hours using an oil bath. Next, 1.31 g (0.008 mol) of 5-norbornene-2,3-dicarboxylic anhydride dissolved in 7 g of N-methyl-2-pyrrolidone was added, and the mixture was further stirred for 12 hours to complete the reaction. After filtering the reaction mixture, the reaction mixture was poured into a solution of water / methanol = 3/1 (volume ratio), the precipitate was collected by filtration, washed thoroughly with water, dried under vacuum, and the desired polyamide resin ( A-1) was obtained.
[Preparation of resin composition]
Soluble in 10 g of synthesized polyamide resin (A-1), 2 g of photosensitive diazoquinone represented by the following formula (B-1), 1 g of a compound having a phenolic hydroxyl group represented by the following formula (C-1), and 70 g of γ-butyrolactone Then, the mixture was filtered through a 0.2 μm fluororesin filter to obtain a positive photosensitive resin composition.
[Developability evaluation]
This positive photosensitive resin composition was applied onto a silicon wafer using a spin coater and then dried on a hot plate at 120 ° C. for 4 minutes to obtain a coating film having a thickness of about 5 μm. Through this coating film, a mask made by Toppan Printing Co., Ltd. (test chart No. 1: remaining pattern and blank pattern with a width of 0.88 to 50 μm are drawn), Nikon Corporation i-line stepper NSR-4425i The exposure amount was increased by 200 mJ / cm ² to 20 mJ / cm ² steps. Next, the exposed portion was dissolved and removed by immersing in a 2.38% tetramethylammonium hydroxide aqueous solution for 80 seconds, and then rinsed with pure water for 30 seconds. When the pattern was observed, it was confirmed that the 10 μm pattern was well opened.
[Evaluation of the physical properties]
This positive photosensitive resin composition was applied on a 6-inch silicon wafer using a spin coater so as to have a thickness of 5 μm after curing, and then dried on a hot plate at 120 ° C. for 4 minutes, and then using a clean oven. Curing was performed at an oxygen concentration of 1000 ppm or less at 150 ° C./30 minutes + 320 ° C./30 minutes.

  Next, the obtained cured film was subjected to a reflow resistance test. BF-30 (manufactured by Arakawa Chemical) was applied as a flux on the cured film and passed through 260 ° C. reflow twice. Thereafter, the flux was removed by washing with xylene and isopropanol, and the surface of the cured film was observed with an optical microscope, but no cracks or wrinkles were observed.

Next, a tensile test was performed. A cured film having a width of 10 mm was pulled at a rate of 5 mm / min with a tensile measuring machine and measured. The tensile elastic modulus was 5.2 GPa.
Example 2
[Synthesis of polyamide resin]
In the synthesis of the polyamide resin of Example 1, 1,3-dihydro-1,3-dioxo-5-isobenzofurancarboxylic acid-1,4-phenylene ester was replaced with 1,3-dihydro-1,3-dioxo- Except for changing to 5.50 g (0.012 mol) of 5-isobenzofurancarboxylic acid-1,4-phenylene ester and 1.18 g (0.004 mol) of 4,4′-biphenyltetracarboxylic dianhydride A polyamide resin was synthesized (A-2) in the same manner as in Example 1.
[Production of resin composition, developability and evaluation of physical properties]
Using the obtained polyamide resin (A-2), a positive photosensitive resin composition was produced and evaluated in the same manner as in Example 1.
Example 3
[Synthesis of polyamide resin]
In the synthesis of the polyamide resin of Example 1, 1.30 g (0.012 mol) of 1,3-phenylenediamine and 0.87 g (0.008 mol) of 1,4-phenylenediamine were combined with 2,2′-bis (tri (Fluoromethyl) benzidine 1.92 g (0.006 mol), 1,3-phenylenediamine 1.30 g (0.012 mol) and 1,4-phenylenediamine 0.22 g (0.002 mol) Were synthesized in the same manner as in Example 1 (A-3).
[Production of resin composition, developability and evaluation of physical properties]
Using the obtained polyamide resin (A-3), a positive photosensitive resin composition was produced and evaluated in the same manner as in Example 1.
<< Comparative Example 1 >>
[Synthesis of polyamide resin]
In the synthesis of the polyamide resin of Example 1, 4.71 g (0.016 mol) of 4,4′-biphenyltetracarboxylic dianhydride, 1.30 g (0.012 mol) of 1,3-phenylenediamine and 1,1 A polyamide resin was synthesized (A-4) in the same manner as in Example 1 except that the amount was changed to 0.87 g (0.008 mol) of 4′-phenylenediamine.
[Preparation of resin composition]
An attempt was made to dissolve 10 g of the synthesized polyamide resin (A-4) and 2 g of photosensitive diazoquinone (B-1) having the following structure in 70 g of γ-butyrolactone, but it finally became a gel. Therefore, dissolution was performed with N-methyl-pyrrolidone, and the same evaluation as in Example 1 was performed. Regarding the workability evaluation, the 10 um pattern did not open well. The reflow resistance was good. The elastic modulus was 4.8 GPa.
<< Comparative Example 2 >>
[Production of resin composition, developability and evaluation of physical properties]
In the synthesis of the polyamide resin in Comparative Example 1, 1.30 g (0.012 mol) of 1,3-phenylenediamine and 0.87 g (0.008 mol) of 1,4′-phenylenediamine were added to 1,3-phenylenediamine. A polyamide resin was synthesized (A-5) in the same manner as in Comparative Example 1 except that 0.87 g (0.008 mol) and 1,4′-phenylenediamine were changed to 1.30 g (0.012 mol). [Production of resin composition, developability and evaluation of physical properties]
Using the obtained polyamide resin (A-5), a positive photosensitive resin composition was prepared and evaluated in the same manner as in Example 1. However, as in Example 2, it was dissolved in γ-butyrolactone. The sample was dissolved in N-methyl-pyrrolidone in the same manner as in Comparative Example 1 and evaluated in the same manner as in Comparative Example 1.

  The present invention relates to a positive photosensitive resin composition that can realize a relatively high yield with a high elastic modulus and can be developed with an alkali developer, and includes a surface protective film for a semiconductor element, an interlayer insulating film, and a surface protective film for a display element It is preferably used for an interlayer insulating film or the like.

The expanded sectional view of the pad part of an example of the semiconductor device which has a bump of the present invention is shown.

Explanation of symbols

1 Silicon wafer 2 Al pad 3 Passivation film 4 Buffer coat film 5 Metal (Cr, Ti, etc.) film 6 Wiring (Al, Cu, etc.)
7 Insulating film 8 Barrier metal 9 Solder bump

Claims (9)

(A) a polyamide resin represented by the general formula (1), and
(B) a photosensitive diazoquinone compound,
A positive photosensitive resin composition comprising:

(In the formula, n is an integer of 1 or more. X and Y are organic groups, and at least one Y ₁ is included in Y included in the polyamide resin.)

(In the formula, R ₁ and R ₂ are organic groups and may be the same or different. M and n are integers of 1 or more. They may be the same or different.) The positive photosensitive resin composition according to claim _1, wherein Y ₁ is represented by the following formula.

(R ₃ and R ₄ are hydrogen or a hydrocarbon group and may be the same or different.) 3. The positive photosensitive resin composition according to claim ₁ , wherein a proportion of Y ₁ contained in the polyamide resin is 50 to 100%.   The positive photosensitive resin composition according to claim 1, further comprising (C) a compound having a phenolic hydroxyl group. The positive photosensitive resin composition according to claim 4, wherein the compound (C) having a phenolic hydroxyl group has a structure represented by the following formula.

(Wherein R ₅ and R _{6 each} represent a halogen atom, an alkyl group, an alkoxy group, an alkyl ester group cycloalkyl group or a cycloalkoxy group. R ₅ and R ₆ may be the same or different. M , N is an integer of 0 to 5. p and q are integers of 0 to 3 and p + q ≧ 2.R ₇ is a single bond, a methylene group, an alkylene group, an oxygen atom, a carbonyl group, a carbonyl ether group. , Represents a sulfur atom, a sulfonyl group, or an azo group.) Applying the positive photosensitive resin composition according to any one of claims 1 to 5 on a substrate to form a composition layer;
Irradiating active energy rays to a desired portion of the composition layer, and then contacting with a developer to form a pattern; and
Heating the composition layer;
A pattern forming method comprising: A semiconductor substrate, a semiconductor element provided on the semiconductor substrate, and an insulating film provided on the semiconductor element;
The semiconductor device, wherein the insulating film is a film formed from the positive photosensitive resin composition according to claim 1. A display element substrate, an insulating film covering the surface, and a display element provided on the display element substrate;
The light emitting device, wherein the insulating film is a film formed from the positive photosensitive resin composition according to any one of claims 1 to 5. A method of manufacturing a semiconductor device comprising a semiconductor chip and a protective film covering the surface thereof,
Applying a positive photosensitive resin composition on the semiconductor chip to form a resin layer;
Irradiating an active energy ray to a desired portion of the resin layer; and
A step of bringing the developer into contact with the resin layer after irradiation with active energy rays, and then forming the protective film by heating the resin layer;
Including
A method of manufacturing a semiconductor device, wherein the positive photosensitive resin composition is the positive photosensitive resin composition according to claim 1.

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