Pattern forming method
A pattern-forming method includes applying an inorganic film-forming composition on an upper face side of a substrate to provide an inorganic film, forming a resist pattern on an upper face side of the inorganic film; and dry-etching once or several times using the resist pattern as a mask such that the substrate has a pattern The inorganic film-forming composition includes a polyacid or a salt thereof, and an organic solvent. The step for forming a resist pattern may include the steps of: applying a resist composition on an upper face side of the inorganic film to provide a resist film; exposing the resist film; and developing the resist film exposed.
1. A pattern-forming method comprising:
applying an inorganic film-forming composition on an upper face side of a substrate to provide an inorganic film;
forming a resist pattern on an upper face side of the inorganic film; and
dry-etching once or several times using the resist pattern as a mask such that the substrate has a pattern,
wherein the inorganic film-forming composition comprises:
a polyacid or a salt thereof;
an organic solvent; and
a compound represented by formula (1):
R 1 —CO—CHR 3 —CO—R 2 (1)
wherein, in the formula (1), R 1 and R 2 each independently represent a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms or a substituted or unsubstituted oxyhydrocarbon group having 1 to 20 carbon atoms; and R 3 represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms.
2. The pattern-forming method according to claim 1 , wherein the resist pattern is formed by:
applying a resist composition on an upper face side of the inorganic film to provide a resist film;
exposing the resist film; and
developing the resist film exposed.
3. The pattern-forming method according to claim 1 , wherein a metal element composing the polyacid or the salt thereof is titanium, zirconium, vanadium, niobium, tantalum, molybdenum, tungsten or a combination thereof.
4. The pattern-forming method according to claim 1 , wherein the polyacid is an isopolyacid, a heteropolyacid or a combination thereof.
5. The pattern-forming method according to claim 4 , wherein the isopolyacid comprises an anion represented by formula (2):
[M x O y ] m− (2)
wherein, in the formula (2), M represents titanium, zirconium, vanadium, niobium, tantalum, molybdenum or tungsten; x is an integer of 1 to 200; y is an integer of 3 to 2,000; and m is an integer of 1 to 200.
6. The pattern-forming method according to claim 4 , wherein a hetero atom composing the heteropolyacid is phosphorus, silicon or a combination thereof.
7. The pattern-forming method according to claim 6 , wherein the heteropolyacid comprises an anion represented by formula (3):
[X a M b O c ] n− (3)
wherein, in the formula (3), M represents titanium, zirconium, vanadium, niobium, tantalum, molybdenum or tungsten; X represents phosphorus or silicon; a is an integer of 1 to 100; b is an integer of 1 to 200; c is an integer of 3 to 2,000; and n is an integer of 1 to 200, wherein “a” is no greater than “b”.
8. The pattern-forming method according to claim 1 , wherein the inorganic film-forming composition further comprises water.