Method for forming silicon or silicon compound pattern in semiconductor manufacturing process

Abstract

Disclosed is a method of forming a fine silicon pattern with a high aspect ratio for fabrication of a semiconductor device. The method includes a cleaning process of removing organic residue or reside originating in fumes using a cleaning solution, thereby enabling formation of a desired pattern while preventing the pattern from being lifted. Thus, the present disclosure enables formation of a fine pattern by using a novel cleaning method.

Claims

1. A method of forming a silicon pattern or a silicon compound pattern in a process of depositing a polymer layer or a predetermined compound layer in the presence of a silicon oxide pattern under a silicon layer or a silicon compound layer, the method comprising: sequentially performing deposition of an organic film and an inorganic film on a silicon oxide pattern, application of a photoresist film, and formation of a photoresist pattern through exposure and development of the photoresist film; performing a first dry etching process using an etching gas with the photoresist pattern being served as an etching mask; cleaning, using a cleaning solution, a wafer with residue of the organic film remaining thereon to prevent pattern lifting attributable to impurities generated during the etching before deposition of the polymer layer or the predetermined compound layer; and performing a second dry etching process to etch the polymer layer or the predetermined compound layer.

2. The method according to claim 1, wherein the cleaning comprises: spraying the cleaning solution at a rate of 1 to 200 mL/s for 1 to 200 seconds with the wafer being rotated; stopping the spraying; and spin-drying the wafer.

3. The method according to claim 2, wherein in the cleaning, the cleaning solution is sprayed in an amount of 20 to 300 mL.

4. The method according to claim 3, wherein in the cleaning, the cleaning solution is sprayed in an amount of 40 to 300 mL.

5. The method according to claim 4, wherein in the cleaning, the cleaning solution is sprayed in an amount of 50 to 300 mL.

6. The method according to claim 1, wherein the deposition of the organic film and the inorganic film on an etching target is chemically or physically performed.

7. The method according to claim 6, wherein the organic film on the etching target has a carbon content of 30% to 100%.

8. The method according to claim 1, wherein a light source for the formation of the pattern emits light of a 13.5-nm wavelength, a 198-nm wavelength, a 248-nm wavelength, or a 365-nm wavelength or an e-beam.

9. The method according to claim 1, wherein the etching gas used for the dry etching process after the formation of the pattern comprises a gas or a mixture of two or more gases selected from among inert gases such as argon or nitrogen, gases of molecules containing one or more fluorine atoms, and oxygen.

10. The method according to claim 1, wherein the cleaning solution comprises 1% to 100% by weight of a material capable of washing polymer residue off, 0% to 99% by weight of a solvent, 0% to 3% by weight of a surfactant, and 0% to 10% by weight of an alkali compound.

11. The method according to claim 10, wherein the material capable of washing polymer residue off comprises a solvent or a mixture of two or more solvents selected from among alcohol-based solvents, amide-based solvents, ketonic solvents, ester-based solvents, and carbonated hydrogen-based solvents.

12. The method according to claim 10, wherein the alkali compound comprises at least one or a mixture of two or more ones selected from among amines and ammonium hydroxides.

Description

MODE FOR INVENTION

Examples 1 to 10 and Comparison Examples 1 to 2

Example 1

(1) On the substrate with the patterned layer, a spin-on-carbon (SOC) layer, which is an organic carbon film, was formed to be 1,000 Å thick and backed at 400° C. for 3 minutes. Next, an SiON layer, which is an inorganic film, was formed to be 300 Å thick by a chemical vapor deposition method. Next, a photoresist film for an KrF light source was formed to be 2,000 Å thick, followed by exposure at 24 mj using a Nikon 204B KrF exposure apparatus, resulting in a photoresist mask having a 200 nm pattern. The deposited film was etched down, using a dry etching method, to the oxide layer, which was a base layer (i.e., substrate), using the formed mask and an etching gas. Next, a cleaning solution composed of 80% of isopropyl alcohol, 17.9% of ethylene glycol, 2% of tetraethylammonium hydroxide, and 0.1% of polyoxyethylene lauryl ester was sprayed onto the base layer (substrate) at a rate shown in Table 1. Next, a polymer layer was formed to be 300 Å thick on the substrate by chemical vapor deposition and dry etched to form a final desired pattern.

Examples 2 to 10

(2) The process was performed in the same manner as in Example 1 to form a desired pattern, except that the amount of the cleaning solution sprayed varied as in Table 1.

Comparative Examples 1 to 2

(3) The process was performed in the same manner as in Example 1 to form a desired pattern, except that the amount of the cleaning solution sprayed varied as in Table 1.

(4) The process was performed in the same manner as in Example 1 to form a desired pattern, except that the cleaning solution was not used.

(5) Characterization

(6) The patterns formed in Examples 1 to 10 and Comparative Examples 1 to 2 were observed to check whether the patterns were lifted or not. The results were represented in values. The values are determined by the criteria shown below.

(7) <Criteria for Evaluation Values>

(8) 0: lifting was observed from 100% of the observed patterns.

(9) 1: lifting was observed from 90% of the observed patterns.

(10) 2: lifting was observed from 80% of the observed patterns.

(11) 3: lifting was observed from 70% of the observed patterns.

(12) 4: lifting was observed from 60% of the observed patterns.

(13) 5: lifting was observed from 50% of the observed patterns.

(14) 6: lifting was observed from 40% of the observed patterns.

(15) 7: lifting was observed from 30% of the observed patterns.

(16) 8: lifting was observed from 20% of the observed patterns.

(17) 9: lifting was observed from 10% of the observed patterns.

(18) 10: lifting was observed from 0% of the observed patterns.

(19) TABLE-US-00001 TABLE 1 Amount of Lifting ejection evaluation (mL) value Example 1 20 4 Example 2 30 6 Example 3 40 8 Example 4 50 10 Example 5 100 10 Example 6 150 10 Example 7 200 10 Example 8 210 10 Example 9 220 10 Example 10 300 10 Comparative — 0 Example 1 Comparative 10 1 Example 2

(20) As shown in Table 1, first, in Comparative Examples 1 and 2 in which the cleaning solution was sprayed in an amount of 0 to 10 mL, the evaluation values of the patterns ranged from 0 to 1, indicating a poor result.

(21) Second, in Examples 1 to 2 in which the cleaning solution was sprayed in an amount of 2˜30 mL, the evaluation values ranged from 4 to 6, indicating a good result.

(22) Third, in Example 3 in which the cleaning solution was sprayed in an amount of 40 mL, the evaluation value was 8, indicating a better result.

(23) Fourth, in Examples 4 to 10 in which the cleaning solution was sprayed in an amount of 50 300 mL, the evaluation values were 10, indicating the best result.