Etching method and method for manufacturing semiconductor element
Provided is an etching method capable of selectively etching an etching target containing a silicon compound including at least one of a nitrogen atom or an oxygen atom and a silicon atom with respect to a specific non-etching target without using plasma. The etching method includes an etching step in which an etching gas containing fluorine gas is brought into contact with a member to be etched including an etching target and a non-etching target in the absence of plasma to selectively etch the etching target with respect to the non-etching target. The etching target contains a silicon compound including at least one of a nitrogen atom or an oxygen atom and a silicon atom. The non-etching target includes at least one selected from tantalum, cobalt, copper, titanium nitride, nickel, and amorphous carbon. The etching step is performed under temperature conditions of from 40° C. to less than 350° C.
1. An etching method comprising an etching step in which an etching gas containing fluorine gas is brought into contact with a member to be etched including an etching target being a target of etching with the etching gas and a non-etching target not being the target of the etching with the etching gas in an absence of plasma to selectively etch the etching target with respect to the non-etching target, wherein the etching target contains a silicon compound including at least one of a nitrogen atom or an oxygen atom and a silicon atom;
wherein the non-etching target includes at least one selected from tantalum, cobalt, copper, titanium nitride, nickel, and amorphous carbon;
wherein the etching step is performed under temperature conditions of from 40° C. to less than 350° C.;
wherein the etching gas consists of only fluorine gas or consists of a mixed gas consisting of fluorine gas and an inert gas.
2. The etching method according to claim 1 , wherein the inert gas is at least one selected from nitrogen gas, helium, argon, neon, krypton, and xenon.
3. The etching method according to claim 2 , wherein an amount of the fluorine gas contained in the etching gas is from 0.5% by volume to 70% by volume.
4. The etching method according to claim 1 , wherein an amount of the fluorine gas contained in the etching gas is from 0.5% by volume to 70% by volume.
5. The etching method according to claim 1 , wherein the non-etching target is used as a resist in the etching of the etching target with the etching gas.
6. The etching method according to claim 1 , wherein an etching selectivity ratio being a ratio of an etching rate of the etching target to an etching rate of the non-etching target is 3 or more.
7. A method for manufacturing a semiconductor element, the method using the etching method according to claim 1 to manufacture the semiconductor element, wherein the member to be etched is a semiconductor substrate including the etching target and the non-etching target; and wherein the method comprises a processing step of removing at least a part of the etching target from the semiconductor substrate by the etching.
8. The etching method according to claim 1 , wherein the silicon compound is at least one of silicon oxide or silicon nitride.
9. The etching method according to claim 8 , wherein the etching step is performed under pressure conditions of from 1 Pa to 100 kPa.
10. The etching method according to claim 8 , wherein the etching step is performed under temperature conditions of from 70° C. to 330° C.
11. The etching method according to claim 8 , wherein the etching gas is a gas comprising only fluorine gas or is a mixed gas containing fluorine gas and inert gas.
12. The etching method according to claim 8 , wherein an amount of the fluorine gas contained in the etching gas is from 0.5% by volume to 70% by volume.
13. The etching method according to claim 1 , wherein the etching step is performed under pressure conditions of from 1 Pa to 100 kPa.
14. The etching method according to claim 13 , wherein the etching step is performed under temperature conditions of from 70° C. to 330° C.
15. The etching method according to claim 13 , wherein the etching gas is a gas comprising only fluorine gas or is a mixed gas containing fluorine gas and inert gas.
16. The etching method according to claim 13 , wherein an amount of the fluorine gas contained in the etching gas is from 0.5% by volume to 70% by volume.
17. The etching method according to claim 1 , wherein the etching step is performed under temperature conditions of from 70° C. to 330° C.
18. The etching method according to claim 17 , wherein the etching gas is a gas comprising only fluorine gas or is a mixed gas containing fluorine gas and inert gas.
19. The etching method according to claim 17 , wherein an amount of the fluorine gas contained in the etching gas is from 0.5% by volume to 70% by volume.