KR940005612B1 - Photo-resist composition use deep ultraviolet rays - Google Patents

Abstract

Photoresist composition for lithography using deep ultraviolet in which polyvinyl copolymer is used as photo cross-linking polymeric resin and melamin derivative as cross-linking agent is provided. The composition is thermally stable to plasma so that the processing condition of the semiconductor can be satisfied.

Description

Photoresist Composition for Photolithography Using Deep UV

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for preparing a negative photoresist for photolithography (photolithography) using deep UV, which is used for fabricating semiconductor circuits, and more particularly to plasma etching. It is characterized by providing a composition for producing a photoresist having good resistance and resolution up to 0.4 µm.

Until now, melamine, epoxy and bis-azides, etc., have been mainly used as a crosslinking agent based on a noblock resin to produce g- or i-ray resists, but this is a pattern of high resolution in Deep UV. Not only was it insufficient to obtain), but it was also unsuitable for resistance due to plasma etching.

Therefore, it is necessary to develop a new resin composition for photoresist to overcome the above drawbacks. Accordingly, the present invention provides a photoresist that is particularly suitable for deep UV, especially at 248 nm, and has a pattern of etching resistance and ultrafine structure of 0.4 mu. To provide a composition for preparing a negative photoresist obtainable, a polyvinyl copolymer of general formula (I), such as poly (p-vinyl) phenol copolymer [Poly ( p-vinyl) phenol copolymer] is characterized in that the addition of the melamine-based compound of formula (II) as a crosslinking agent.

Wherein n is an integer greater than or equal to 1,000, R 'is a hydrogen atom or a 4-6 nitrogen ring compound, and R "is a hydrogen atom or 4-10 alkyl atoms and 2-10 alkyl atoms substituted. As the aryl group, R 'and R' 'are not the same substituent and at least one may be an alkoxy ketone having 4-10 carbon atoms.

In the above formula, R ″ is an alkyl group having 1-3 substituted halogen atoms, and has 1-3 carbon atoms, and three R ″ may be the same or different from each other. In addition, a nitrogen atom may be substituted instead of sulfur (S), in which case R '' may be an alkyl group having 4-10 carbon atoms. In addition, when the R '' substituent is an alkyl group of hexaethoxy group, sulfur is characterized by being a nitrogen atom.

In addition, S-triazine compound, phenylene / anthracene, 1,3,4-oxadiazole compound and Onium salt, etc. may be used as the photoacid generator used as the initiator in the present invention. The structural characteristics of the PAG are shown in Table 3.

Photocrosslinkable polymer resins and crosslinker compounds associated with Formulas (I) and (II) used in the present invention are illustrated in Tables 1 and 2.

TABLE 1

TABLE 2

TABLE 3

Example 1

51 g of Compound 4 in Table 1 as a photocrosslinkable polymer resin, 6 g of Compound B in Table 2 as a crosslinking agent, and 3 g of Compound Bar in Table 3 were dissolved in 140 g of diethylene glycol dimethyl ether as a solvent. Photoresist was prepared by purification. This is applied to a photolithography process of an excimer (KrF: 248 nm) light source. Here, the coating thickness of the silicon wafer was 1.0 탆 and treated with PEB and alkaline properties at 115 ° C.

The final photoresist microcircuit pattern (L / S) was observed up to 0.4 μm by electron microscopy (SEM).

Example 2

A photoresist was prepared in the same manner as in Example 1, except that 140 g of a solvent obtained by mixing 2-ethoxyethyl acetate and cyclohexanone in a 1: 1 ratio was used instead of the solvent used in Example 1.

Example 3

Photoresist was prepared in the same manner as in Example 1, except that 51 g of Compound 1 of Table 1 was used as the photocrosslinkable polymer resin.

Example 4

51 g of Compound 2 of Table 1 was used as a photocrosslinkable polymer resin, 6 g of Compound A of Table 2 and 5 g of Compound A of Table 3 were used as a crosslinking agent, and it carried out similarly to Example 1, and prepared the photoresist.

Example 5

Photoresist was prepared in the same manner as in Example 1 using 56 g of Compound 7 in Table 1, 4 g of Compound A in Table 2, and 3 g of Onium salt in Table 3 as the photocrosslinkable polymer resin.

Example 6-8

Photoresist was prepared in the same manner as in Example 1, except that Compound 3 in Table 1 was used in an amount of 45 g, 49 g, and 56 g, respectively, as the photocrosslinkable polymer resin.

Example 9-10

Except that 51g of Compound 4 of Table 1 was used as the photocrosslinkable polymer resin and 5g and 8g of Compound B of Table 2 were used as the crosslinking agents, respectively, the same procedure as in Example 1 was carried out, and the microstructure pattern in the excimer (248 nm) light source was possible. Photoresist was prepared. This photoresist had particularly good physicochemical properties in the plasma etching process.

As for the physical property test of Example 2-10 mentioned above, the L / S pattern of 0.4 micrometer was observed in the same manner as in Example 1.

The photoresist compositions of the photolithography using Deep-UV prepared by the method of Example 1-10 were each purified by a 0.1 μm thin film filter (Millipore) to remove fine particle impurities, followed by spin coating of 10,000Å. The thickness was applied to the silicon wafer.

The deep UV lithography process enabled the fabrication of 0.4µm L / S microcircuits, and the thermal stability by plasma was particularly excellent, which greatly satisfied the process conditions of the semiconductor.

Claims (1)

In the composition of the photoresist for lithography using Deep UV, the polyvinyl copolymer of general formula (I) is used as the photocrosslinkable polymer resin, and the melamine derivative of general formula (II) as a crosslinking agent A composition of a photoresist for photolithography using di-op ultraviolet light, characterized in that the mixing. Wherein n is an integer greater than or equal to 1,000, R 'is a hydrogen atom or a 4-6 nitrogen ring compound, and R' 'is a hydrogen atom or a 4-10 alkyl group and a carbon atom 2-10 alkyl group substituted As an aryl group, R 'and R' 'are not the same substituents and at least one may be an alkoxyketone group having 4-10 carbon atoms. R '' 'is an alkyl group having 1-3 substituted halogen atoms, containing 1-3 carbon atoms, and three R' '' may be different from each other. In addition, S denotes a sulfur atom, but a nitrogen atom may be substituted instead, in which case R '' 'may be an alkyl group having 4-10 carbon atoms, and when R' '' substituent is an alkyl group of hexaethoxy group, sulfur (S) is a nitrogen source. Become self.