Silicone structure-containing polymer, photosensitive resin composition, photosensitive resin coating, photosensitive dry film, laminate, and pattern forming process

Abstract

A photosensitive resin composition comprising a silicone structure-containing polymer having crosslinking groups or crosslinking reaction-susceptible reactive sites in the molecule is coated onto a substrate to form a photosensitive resin coating which has improved substrate adhesion, a pattern forming ability, crack resistance, heat resistance, and reliability as protective film.

Claims

1. A silicone structure-containing polymer comprising recurring units having the formula (a1) and recurring units having the formula (b1): ##STR00042## wherein R.sup.1 to R.sup.4 are each independently a C.sub.1-C.sub.8 monovalent hydrocarbon group, m and n are each independently an integer of 0 to 300, X.sup.1 is a divalent group having the formula (1): ##STR00043## wherein R.sup.11 is each independently hydrogen or a C.sub.1-C.sub.8 monovalent hydrocarbon group in which at least one hydrogen may be substituted by halogen, R.sup.12 is each independently a C.sub.1-C.sub.8 straight, branched or cyclic alkylene group in which any methylene moiety may be substituted by an ether bond or phenylene moiety, R.sup.13 is each independently hydrogen, a C.sub.1-C.sub.8 monovalent hydrocarbon group, hydroxyl group or glycidyl group, p and q are each independently an integer of 0 to 4, Y.sup.1 is a divalent organic group having the formula (1-1), (1-2) or (1-3): ##STR00044## wherein R.sup.14 is a C.sub.1-C.sub.8 monovalent hydrocarbon group in which at least one hydrogen may be substituted by halogen, Y.sup.2 is a divalent organic group, r and s are each independently an integer of 0 to 3, t and u are each independently an integer of 0 to 2.

2. The silicone structure-containing polymer of claim 1 wherein Y.sup.2 is a group selected from the following groups: ##STR00045## ##STR00046## wherein R is each independently halogen, or a C.sub.1-C.sub.8 straight, branched or cyclic alkyl or haloalkyl group, w is an integer of 1 to 6, x is an integer of 0 to 4, and y and z are each independently an integer of 0 to 4.

3. The silicone structure-containing polymer of claim 1, further comprising recurring units having the formula (a2) and recurring units having the formula (b2): ##STR00047## wherein R.sup.1 to R.sup.4, m and n are as defined above, X.sup.2 is a divalent group having the formula (2): ##STR00048## wherein Z.sup.1 is a single bond or a divalent organic group selected from the following: ##STR00049## R.sup.21 is each independently hydrogen or methyl, R.sup.22 and R.sup.23 are each independently a C.sub.1-C.sub.4 straight, branched or cyclic alkyl group or a C.sub.1-C.sub.4 straight, branched or cyclic alkoxy group, a is each independently an integer of 0 to 7, b and c are each independently an integer of 0 to 2.

4. The silicone structure-containing polymer of claim 1, further comprising recurring units having the formula (a3) and recurring units having the formula (b3): ##STR00050## wherein R.sup.1 to R.sup.4, m and n are as defined above, X.sup.3 is a divalent group having the formula (3): ##STR00051## wherein Z.sup.2 is a single bond or a divalent organic group selected from the following: ##STR00052## R.sup.31 is each independently hydrogen or methyl, R.sup.32 and R.sup.33 are each independently a C.sub.1-C.sub.4 straight, branched or cyclic alkyl group or a C.sub.1-C.sub.4 straight, branched or cyclic alkoxy group, d is each independently an integer of 0 to 7, e and f are each independently an integer of 0 to 2.

5. The silicone structure-containing polymer of claim 1, further comprising recurring units having the formula (a4) and recurring units having the formula (b4): ##STR00053## wherein R.sup.1 to R.sup.4, m and n are as defined above, X.sup.4 is a divalent group having the formula (4): ##STR00054## wherein R.sup.41 is each independently hydrogen or methyl, and g is each independently an integer of 0 to 7.

6. The silicone structure-containing polymer of claim 1, further comprising recurring units having the formula (a5) and recurring units having the formula (b5): ##STR00055## wherein R.sup.1 to R.sup.4, m and n are as defined above, X.sup.5 is a divalent group having the formula (5): ##STR00056## wherein R.sup.51 is each independently hydrogen or methyl, R.sup.52 and R.sup.53 are each independently a C.sub.1-C.sub.8 monovalent hydrocarbon group, j and k are each independently an integer of 0 to 300, and h is each independently an integer of 0 to 7.

7. A photosensitive resin composition comprising (A) a base resin containing the silicone structure-containing polymer of claim 1 and (B) a photoacid generator.

8. The photosensitive resin composition of claim 7, further comprising (C) a crosslinker.

9. The photosensitive resin composition of claim 8 wherein the crosslinker (C) is at least one compound selected from the group consisting of an amino condensate modified with formaldehyde or formaldehyde-alcohol, a phenol compound having on the average at least two methylol or alkoxymethylol groups in the molecule, and an epoxy compound having on the average at least two epoxy groups in the molecule.

10. The photosensitive resin composition of claim 7, further comprising (D) a solvent.

11. The photosensitive resin composition of claim 7, further comprising (E) a basic compound.

12. A photosensitive resin coating formed of the photosensitive resin composition of claim 7.

13. A photosensitive dry film comprising a support film and the photosensitive resin coating of claim 12 thereon.

14. A laminate comprising a substrate having grooves and/or holes having an opening width of 10 to 100 μm and a depth of 10 to 120 μm and the photosensitive resin coating of claim 12 thereon.

15. A pattern forming process comprising the steps of: (i) coating the photosensitive resin composition of claim 7 onto a substrate to form a photosensitive resin coating thereon, (ii) exposing a predetermined region of the photosensitive resin coating to radiation through a photomask and post-exposure baking, and (iii) developing the photosensitive resin coating as post-exposure baked in a developer to dissolve away the unexposed region of the resin coating and to form a pattern of the resin coating.

16. A pattern forming process comprising the steps of: (i) attaching the photosensitive dry film of claim 13 at its photosensitive resin coating to a substrate to dispose the photosensitive resin coating thereon, (ii) exposing a predetermined region of the photosensitive resin coating to radiation through a photomask and post-exposure baking, and (iii) developing the photosensitive resin coating as post-exposure baked in a developer to dissolve away the unexposed region of the resin coating and to form a pattern of the resin coating.

17. The pattern forming process of claim 15, further comprising (iv) post-curing the patterned resin coating resulting from development step (iii) at a temperature of 100 to 250° C.

18. The pattern forming process of claim 15 wherein the substrate has grooves and/or holes having an opening width of 10 to 100 μm and a depth of 10 to 120 μm.

19. The photosensitive resin composition of claim 7 which is to form a coating for protecting electric and electronic parts.

20. The photosensitive resin composition of claim 7 which is to form a coating for bonding two substrates together.

Description

EXAMPLE

(1) Examples of the invention are given below by way of illustration and not by way of limitation. Notably, the weight average molecular weight (Mw) is measured by gel permeation chromatography (GPC) versus monodisperse polystyrene standards using GPC column TSKgel Super HZM-H (Tosoh Corp.) under analytical conditions: flow rate 0.6 mL/min, tetrahydrofuran elute, and column temperature 40° C. All parts are by weight (pbw).

(2) Compounds (S-1) to (S-7) used in Examples and Comparative Examples are shown below.

(3) ##STR00040##
[1] Synthesis of Siloxane Structure-Containing Polymers

Example 1

(4) Synthesis of Resin 1

(5) A 3-L flask equipped with a stirrer, thermometer, nitrogen purge line and reflux condenser was charged with 19.6 g (0.05 mol) of Compound (S-1), 13.3 g (0.05 mol) of Compound (S-2), 162.5 g (0.25 mol) of Compound (S-3a), and 64.5 g (0.15 mol) of Compound (S-7), further with 2,000 g of toluene, and heated at 70° C. Thereafter, 1.0 g of a toluene solution of chloroplatinic acid (platinum concentration 0.5 wt %) was added, and 58.2 g (0.30 mol) of Compound (S-5) and 604.0 g (0.20 mol) of Compound (S-6) wherein y.sup.1=40 (Shin-Etsu Chemical Co., Ltd.) were added dropwise over 1 hour. The molar ratio of the total amount of hydrosilyl groups to the total amount of alkenyl groups was 1/1. At the end of dropwise addition, the reaction solution was heated at 100° C. and aged for 6 hours. Toluene was distilled off in vacuum from the reaction solution, yielding Resin 1. On .sup.1H—NMR and .sup.29Si—NMR spectroscopy (Bruker Corp.), Resin 1 was identified to contain recurring units having formulae (a1) to (a4) and (b1) to (b4). On GPC analysis, it was confirmed that the peaks assigned to the reactants had disappeared, proving that a polymer corresponding to the charge ratio was synthesized. Resin 1 had a Mw of 42,000 and a silicone content of 65.5 wt %.

Example 2

(6) Synthesis of Resin 2

(7) A 3-L flask equipped with a stirrer, thermometer, nitrogen purge line and reflux condenser was charged with 19.6 g (0.05 mol) of Compound (S-1), 13.3 g (0.05 mol) of Compound (S-2), 133.0 g (0.25 mol) of Compound (S-3b), and 64.5 g (0.15 mol) of Compound (S-7), further with 2,000 g of toluene, and heated at 70° C. Thereafter, 1.0 g of a toluene solution of chloroplatinic acid (platinum concentration 0.5 wt %) was added, and 58.2 g (0.30 mol) of Compound (S-5) and 604.0 g (0.20 mol) of Compound (S-6) wherein y.sup.1=40 (Shin-Etsu Chemical Co., Ltd.) were added dropwise over 1 hour. The molar ratio of the total amount of hydrosilyl groups to the total amount of alkenyl groups was 1/1.

(8) At the end of dropwise addition, the reaction solution was heated at 100° C. and aged for 6 hours. Toluene was distilled off in vacuum from the reaction solution, yielding Resin 2.

(9) On .sup.1H—NMR and .sup.29Si—NMR spectroscopy (Bruker Corp.), Resin 2 was identified to contain recurring units having formulae (a1) to (a4) and (b1) to (b4). On GPC analysis, it was confirmed that the peaks assigned to the reactants had disappeared, proving that a polymer corresponding to the charge ratio was synthesized. Resin 2 had a Mw of 43,000 and a silicone content of 67.7 wt %.

Example 3

(10) Synthesis of Resin 3

(11) A 3-L flask equipped with a stirrer, thermometer, nitrogen purge line and reflux condenser was charged with 19.6 g (0.05 mol) of Compound (S-1), 13.3 g (0.05 mol) of Compound (S-2), 135.5 g (0.25 mol) of Compound (S-3c), and 64.5 g (0.15 mol) of Compound (S-7), further with 2,000 g of toluene, and heated at 70° C. Thereafter, 1.0 g of a toluene solution of chloroplatinic acid (platinum concentration 0.5 wt %) was added, and 58.2 g (0.30 mol) of Compound (S-5) and 604.0 g (0.20 mol) of Compound (S-6) wherein y.sup.1=40 (Shin-Etsu Chemical Co., Ltd.) were added dropwise over 1 hour. The molar ratio of the total amount of hydrosilyl groups to the total amount of alkenyl groups was 1/1. At the end of dropwise addition, the reaction solution was heated at 100° C. and aged for 6 hours. Toluene was distilled off in vacuum from the reaction solution, yielding Resin 3. On .sup.1H—NMR and .sup.29Si—NMR spectroscopy (Bruker Corp.), Resin 3 was identified to contain recurring units having formulae (a1) to (a4) and (b1) to (b4). On GPC analysis, it was confirmed that the peaks assigned to the reactants had disappeared, proving that a polymer corresponding to the charge ratio was synthesized. Resin 3 had a Mw of 42,000 and a silicone content of 67.5 wt %.

Example 4

(12) Synthesis of Resin 4

(13) A 3-L flask equipped with a stirrer, thermometer, nitrogen purge line and reflux condenser was charged with 39.2 g (0.10 mol) of Compound (S-1), 26.5 g (0.10 mol) of Compound (S-2), 32.5 g (0.05 mol) of Compound (S-3a), 9.3 g (0.05 mol) of Compound (S-4), and 86.0 g (0.20 mol) of Compound (S-7), further with 2,000 g of toluene, and heated at 70° C. Thereafter, 1.0 g of a toluene solution of chloroplatinic acid (platinum concentration 0.5 wt %) was added, and 58.2 g (0.30 mol) of Compound (S-5) and 317.0 g (0.20 mol) of Compound (S-6) wherein y.sup.1=20 (Shin-Etsu Chemical Co., Ltd.) were added dropwise over 1 hour. The molar ratio of the total amount of hydrosilyl groups to the total amount of alkenyl groups was 1/1. At the end of dropwise addition, the reaction solution was heated at 100° C. and aged for 6 hours. Toluene was distilled off in vacuum from the reaction solution, yielding Resin 4. On .sup.1H—NMR and .sup.29Si—NMR spectroscopy (Bruker Corp.), Resin 4 was identified to contain recurring units having formulae (a1) to (a5) and (b1) to (b5). On GPC analysis, it was confirmed that the peaks assigned to the reactants had disappeared, proving that a polymer corresponding to the charge ratio was synthesized. Resin 4 had a Mw of 43,000 and a silicone content of 55.7 wt %.

Example 5

(14) Synthesis of Resin 5

(15) A 3-L flask equipped with a stirrer, thermometer, nitrogen purge line and reflux condenser was charged with 39.2 g (0.10 mol) of Compound (S-1), 26.5 g (0.10 mol) of Compound (S-2), 26.6 g (0.05 mol) of Compound (S-3b), 9.3 g (0.05 mol) of Compound (S-4), and 86.0 g (0.20 mol) of Compound (S-7), further with 2,000 g of toluene, and heated at 70° C. Thereafter, 1.0 g of a toluene solution of chloroplatinic acid (platinum concentration 0.5 wt %) was added, and 58.2 g (0.30 mol) of Compound (S-5) and 317.0 g (0.20 mol) of Compound (S-6) wherein y.sup.1=20 (Shin-Etsu Chemical Co., Ltd.) were added dropwise over 1 hour. The molar ratio of the total amount of hydrosilyl groups to the total amount of alkenyl groups was 1/1. At the end of dropwise addition, the reaction solution was heated at 100° C. and aged for 6 hours. Toluene was distilled off in vacuum from the reaction solution, yielding Resin 5. On .sup.1H—NMR and .sup.29Si—NMR spectroscopy (Bruker Corp.), Resin 5 was identified to contain recurring units having formulae (a1) to (a5) and (b1) to (b5). On GPC analysis, it was confirmed that the peaks assigned to the reactants had disappeared, proving that a polymer corresponding to the charge ratio was synthesized. Resin 5 had a Mw of 45,000 and a silicone content of 56.3 wt %.

Example 6

(16) Synthesis of Resin 6

(17) A 3-L flask equipped with a stirrer, thermometer, nitrogen purge line and reflux condenser was charged with 39.2 g (0.10 mol) of Compound (S-1), 26.5 g (0.10 mol) of Compound (S-2), 27.1 g (0.05 mol) of Compound (S-3c), 9.3 g (0.05 mol) of Compound (S-4), and 86.0 g (0.20 mol) of Compound (S-7), further with 2,000 g of toluene, and heated at 70° C. Thereafter, 1.0 g of a toluene solution of chloroplatinic acid (platinum concentration 0.5 wt %) was added, and 58.2 g (0.30 mol) of Compound (S-5) and 317.0 g (0.20 mol) of Compound (S-6) wherein y.sup.1=20 (Shin-Etsu Chemical Co., Ltd.) were added dropwise over 1 hour. The molar ratio of the total amount of hydrosilyl groups to the total amount of alkenyl groups was 1/1. At the end of dropwise addition, the reaction solution was heated at 100° C. and aged for 6 hours. Toluene was distilled off in vacuum from the reaction solution, yielding Resin 6. On .sup.1H—NMR and .sup.29Si—NMR spectroscopy (Bruker Corp.), Resin 6 was identified to contain recurring units having formulae (a1) to (a5) and (b1) to (b5). On GPC analysis, it was confirmed that the peaks assigned to the reactants had disappeared, proving that a polymer corresponding to the charge ratio was synthesized. Resin 6 had a Mw of 44,000 and a silicone content of 56.3 wt %.

Comparative Example 1

(18) Synthesis of Resin 7

(19) A 3-L flask equipped with a stirrer, thermometer, nitrogen purge line and reflux condenser was charged with 78.4 g (0.20 mol) of Compound (S-1), 39.8 g (0.15 mol) of Compound (S-2), and 64.5 g (0.15 mol) of Compound (S-7), further with 2,000 g of toluene, and heated at 70° C. Thereafter, 1.0 g of a toluene solution of chloroplatinic acid (platinum concentration 0.5 wt %) was added, and 58.2 g (0.30 mol) of Compound (S-5) and 604.0 g (0.20 mol) of Compound (S-6) wherein y.sup.1=40 (Shin-Etsu Chemical Co., Ltd.) were added dropwise over 1 hour. The molar ratio of the total amount of hydrosilyl groups to the total amount of alkenyl groups was 1/1. At the end of dropwise addition, the reaction solution was heated at 100° C. and aged for 6 hours. Toluene was distilled off in vacuum from the reaction solution, yielding Resin 7. Resin 7 had a Mw of 42,000 and a silicone content of 71.5 wt %.

Comparative Example 2

(20) Synthesis of Resin 8

(21) A 3-L flask equipped with a stirrer, thermometer, nitrogen purge line and reflux condenser was charged with 58.8 g (0.15 mol) of Compound (S-1), 26.5 g (0.10 mol) of Compound (S-2), 9.3 g (0.05 mol) of Compound (S-4), and 86.0 g (0.20 mol) of Compound (S-7), further with 2,000 g of toluene, and heated at 70° C. Thereafter, 1.0 g of a toluene solution of chloroplatinic acid (platinum concentration 0.5 wt %) was added, and 58.2 g (0.30 mol) of Compound (S-5) and 317.0 g (0.20 mol) of Compound (S-6) wherein y.sup.1=20 (Shin-Etsu Chemical Co., Ltd.) were added dropwise over 1 hour. The molar ratio of the total amount of hydrosilyl groups to the total amount of alkenyl groups was 1/1. At the end of dropwise addition, the reaction solution was heated at 100° C. and aged for 6 hours. Toluene was distilled off in vacuum from the reaction solution, yielding Resin 8. Resin 8 had a Mw of 45,000 and a silicone content of 57.0 wt %.

(22) [2] Preparation of Photosensitive Resin Compositions

Examples 7 to 17 and Comparative Examples 3 to 4

(23) Photosensitive resin compositions were prepared by combining the resin (Resins 1 to 8), photoacid generator, crosslinker, solvent, and basic compound in accordance with the formulation shown in Table 1, agitating them at room temperature until dissolution, and precision filtering through a Teflon® filter with a pore size of 1.0 μm.

(24) TABLE-US-00001 TABLE 1 Comparative Component Example Example (pbw) 7 8 9 10 11 12 13 14 15 16 17 3 4 (A) Resin 1 100 Resin 2 100 Resin 3 100 100 100 100 100 100 Resin 4 100 Resin 5 100 Resin 6 100 Resin 7 100 Resin 8 100 (B) PAG-1 1 1 1 1 1 1 1 0.1 10 1 1 1 1 (C) CL-1 10 10 10 10 10 10 10 10 10 25 1 10 10 CL-2 3 3 3 3 3 3 3 3 3 35 1 3 3 (D) cyclopentanone 55 55 55 55 55 55 55 55 55 55 55 55 55 (E) AM-1 0.1

(25) In Table 1, photoacid generator PAG-1, crosslinkers CL-1 and CL-2, and basic compound AM-1 are identified below.

(26) ##STR00041##
[3] Preparation of Photosensitive Dry Film

(27) A die coater was used as the film coater and a polyethylene terephthalate (PET) film of 38 μm thick used as the support film. Each of the photosensitive resin compositions in Table 1 was coated onto the support film. The coated film was passed through a hot air circulating oven (length 4 m) set at 100° C. over 5 minutes to form a photosensitive resin coating on the support film, yielding a photosensitive dry film. Using a laminating roll, a polyethylene film of 50 μm thick as the protective film was bonded to the photosensitive resin coating under a pressure of 1 MPa, yielding a protective film-bearing photosensitive dry film. The thickness of each photosensitive resin coating is tabulated in Table 2. The thickness of a resin coating was measured by an optical interference film thickness gauge.

(28) [4] Evaluation of Resin Coating

(29) (1) Pattern Formation and Evaluation

(30) From the protective film-bearing photosensitive dry film, the protective film was stripped off. Using a vacuum laminator TEAM-100RF (Takatori Corp.) with a vacuum chamber set at a vacuum of 80 Pa, the photosensitive resin coating on the support film was closely bonded to a migration test substrate (comb-shaped electrode-bearing substrate, conductor: copper, conductor spacing and width: 20 μm, conductor thickness: 4 μm). The temperature was 110° C. After restoration of atmospheric pressure, the substrate was taken out of the laminator, and the support film was stripped off. Then the photosensitive resin coating was prebaked on a hot plate at 130° C. for 5 minutes for enhancing adhesion to the substrate.

(31) Next, using a contact aligner exposure tool, the photosensitive resin coating was exposed to radiation of 405 nm through a mask having a line-and-space pattern and a contact hole pattern. After exposure, the coated substrate was baked (PEB) on a hot plate at 120° C. for 5 minutes and cooled. This was followed by spray development in propylene glycol monomethyl ether acetate (PGMEA) for 300 seconds for forming a pattern of the resin coating.

(32) The patterned photosensitive resin coating on the substrate was post-cured in an oven at 180° C. for 2 hours while the oven was purged with nitrogen. Under a scanning electron microscope (SEM), the contact hole patterns of 100 μm, 80 μm, 60 μm, 40 μm, and 20 μm were observed in cross section, with the minimum hole pattern in which holes extended down to the film bottom being reported as maximum resolution. From the cross-sectional photo, the contact hole pattern of 80 μm was evaluated for perpendicularity, and rated excellent (⊚) for perpendicular pattern, good (O) for slightly inversely tapered profile, fair (Δ) for inversely tapered profile, and poor (X) for opening failure.

(33) (2) Evaluation of Electric Properties (Dielectric Breakdown Strength)

(34) For the evaluation of dielectric breakdown strength of a photosensitive resin coating of a photosensitive resin composition, each of the photosensitive resin compositions in

(35) Table 1 was coated onto a steel plate of 13 cm×15 cm×0.7 mm (thick) by means of a bar coater and heated in an oven at 180° C. for 2 hours to form a photosensitive resin coating.

(36) The resin composition was coated such that the resulting coating had a thickness of 0.2 μm. The resin coating was tested by a breakdown tester TM-5031AM (Tama Densoku Co., Ltd.) to determine the dielectric breakdown strength thereof

(37) (3) Evaluation of Reliability (Adhesion, Crack Resistance)

(38) Each of the photosensitive resin film-bearing wafers after pattern formation and post-cure in Examples 7 to 17 and Comparative Examples 3 to 4 was cut into specimens of 10 mm squares using a dicing saw with a dicing blade (DAD685 by DISCO Co., spindle revolution 40,000 rpm, cutting rate 20 mm/sec). Ten specimens for each Example were examined by a thermal cycling test (test of holding at −25° C. for 10 minutes and holding at 125° C. for 10 minutes, the test being repeated 1,000 cycles). After the test, it was observed whether or not the resin film peeled from the wafer and whether or not the resin film cracked. The sample was rated “good” when all specimens did not peel or crack, “peeled” when one or more specimens peeled, and “cracked” when one or more specimens cracked.

(39) (4) Evaluation of Heat Resistance

(40) Prior to a heating test, the weight of a specimen (prepared in the above reliability evaluation) was measured. The specimen was held in an oven at 200° C. for 1,000 hours, taken out of the oven, and measured for weight again. The sample was rated good when the weight change before and after the test was less than 0.5%, and poor when the weight change before and after the test was equal to or more than 0.5%.

(41) (5) Evaluation of Chemical Resistance

(42) To examine the solvent resistance of a photosensitive resin coating, especially resistance to NMP which is frequently used in the fabrication of semiconductor devices, a pattern of 10 mm×10 mm was formed on a wafer from each composition by the same procedure as in (3) Evaluation of reliability. The pattern-bearing wafer was immersed in NMP at room temperature for 1 hour, after which it was examined for a film thickness change and outer appearance for evaluating chemical resistance. The sample was rated good (O) when no changes of film thickness and appearance were observed, and poor (X) when any film thickness increase and swell were observed.

(43) The test results of the resin coatings of the photosensitive resin compositions in Table 1 are tabulated in Table 2.

(44) TABLE-US-00002 TABLE 2 Comparative Example Example 7 8 9 10 11 12 13 14 15 16 17 3 4 Resin coating 100.4 100.5 99.7 101.0 100.1 99.9 99.7 100.2 98.9 99.7 100.9 100.3 100.5 thickness (μm) Contact hole pattern ◯ ◯ ◯ ◯ ◯ ◯ ⊚ ◯ ◯ ◯ ◯ ◯ ◯ profile Maximum resolution 80 80 80 80 80 80 60 60 100 100 80 100 100 (μm) Dielectric breakdown 530 540 555 495 550 565 585 505 565 570 580 540 575 strength (V/μm) Reliability Adhesion Good Good Good Good Good Good Good Good Good Good Good Peeled Peeled Crack Good Good Good Good Good Good Good Good Good Good Good Cracked Cracked resistance Heat resistance Good Good Good Good Good Good Good Good Good Good Good Poor Poor Chemical resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯

(45) As is evident from the test results, the photosensitive resin compositions within the scope of the invention experience little film thickness loss, exhibit good resolution, i.e., sufficient properties as photosensitive material. The resin coatings obtained therefrom have improved electric properties (e.g., dielectric breakdown strength), heat resistance and chemical resistance, as well as improved adhesion and crack resistance after the thermal cycling test, and are thus useful as protective film for circuits and electronic parts. Thus photosensitive dry films having more reliability are available.

(46) Japanese Patent Application No. 2017-153884 is incorporated herein by reference.

(47) Although some preferred embodiments have been described, many modifications and variations may be made thereto in light of the above teachings. It is therefore to be understood that the invention may be practiced otherwise than as specifically described without departing from the scope of the appended claims.