Atomic layer etching method and semiconductor device manufacturing method using the same

An atomic layer etching method comprising:

• forming a metal layer on a substrate;
• and
• etching at least a portion of the metal layer,
• wherein the etching at least the portion of the metal layer includes at least one etching cycle,
• the at least one etching cycle includes supplying an active gas including a halogen gas onto the metal layer, and supplying an amine based etching support gas after the supplying the active gas, and
• the supplying the etching support gas includes supplying the etching support gas at a feeding dosage of 50 Tory sec to 70 Tory sec,
• the etching support gas is pentamethyldiethylenetriamine (PMDETA) expressed by the following formula
• wherein H is hydrogen, C is carbon, and N is nitrogen.

A semiconductor device manufacturing method comprising:

• forming an active pattern on a substrate;
• forming a source/drain pattern on the active pattern;
• forming an interlayer insulating film on the source/drain pattern;
• forming a pre-active contact connected with the source/drain pattern, in the interlayer insulating film;
• and
• etching a portion of the pre-active contact,
• wherein the etching the portion of the pre-active contact includes at least one etching cycle,
• the at least one etching cycle includes supplying an active gas onto the pre-active contact, and supplying an etching support gas after supplying the active gas, and
• the etching support gas is expressed by the following general formula
• wherein each of R1, R2, R3, R4 and R5 independently includes hydrogen or a C1-C4 alkyl group, and N is nitrogen.