Negative pattern forming method and resist pattern
A negative pattern forming method, includes: (i) forming a film having a film thickness of 200 nm or more from a chemical amplification resist composition containing (A) a resin capable of increasing a polarity of the resin (A) by an action of an acid to decrease a solubility of the resin (A) for a developer containing one or more organic solvents, (B) a compound capable of generating an acid upon irradiation with an actinic ray or radiation, and (C) a solvent; (ii) exposing the film, so as to form an exposed film; and (iii) developing the exposed film with a developer containing one or more organic solvents.
1. A negative pattern forming method, comprising:
(i) forming a film having a film thickness of 200 nm or more from a chemical amplification resist composition containing (A) a resin capable of increasing a polarity of the resin (A) by an action of an acid to decrease a solubility of the resin (A) for a developer containing one or more organic solvents, (B) a compound capable of generating an acid upon irradiation with an actinic ray or radiation, and (C) a solvent;
(ii) exposing the film, so as to form an exposed film; and
(iii) developing the exposed film with a developer containing one or more organic solvents,
wherein:
the film formed from the chemical amplification resist composition is formed on a substrate not coated with a bottom anti-reflection coating;
the substrate not coated with a bottom anti-reflection coating is a stepped substrate having a step of 10 nm or more in height;
a step in the stepped substrate has a space of 20 nm to 200 nm; and
the dissolution rate of the film formed of the resin (A) for butyl acetate at 25° C. is 25 nm/sec or more.
2. The negative pattern forming method according to claim 1 ,
wherein the resin (A) contains a repeating unit having a group capable of decomposing by an action of an acid to produce a polar group, in an amount of 40 mol% or more based on all repeating units in the resin (A).
3. The negative pattern forming method according to claim 1 ,
wherein the resin (A) has a weight average molecular weight of 5,000 or more.
4. The negative pattern forming method according to claim 1 ,
wherein the developer containing one or more organic solvents contains at least one kind of an organic solvent selected from the group consisting of a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, an amide-based solvent and an ether-based solvent.
5. The negative pattern forming method according to claim 1 , further comprising: (iv) performing rinsing by using a rinsing solution containing one or more organic solvents.
6. The negative pattern forming method according to claim 1 , wherein the
exposing of the film in the step (ii) is exposure to an ArF excimer laser.
7. The negative pattern forming method according to claim 1 ,
wherein the film thickness of the film formed from the chemical amplification resist composition is 600 nm or less.
8. The negative pattern forming method according to claim 1 , wherein the film thickness is 250 nm or more.
9. A manufacturing method of an electronic device, comprising: the negative pattern forming method claimed in claim 1 .