US 11,810,791 B2
Etching method, substrate processing apparatus, and substrate processing system
Hironari Sasagawa, Miyagi (JP); and Maju Tomura, Miyagi (JP)
Assigned to TOKYO ELECTRON LIMITED, Tokyo (JP)
Filed by TOKYO ELECTRON LIMITED, Tokyo (JP)
Filed on Jan. 28, 2021, as Appl. No. 17/160,460.
Claims priority of application No. 2020-012241 (JP), filed on Jan. 29, 2020.
Prior Publication US 2021/0233777 A1, Jul. 29, 2021
Int. Cl. H01L 21/311 (2006.01); H01L 21/3065 (2006.01); H01J 37/32 (2006.01); H01L 21/02 (2006.01); H01L 21/308 (2006.01); H01L 21/3213 (2006.01)
CPC H01L 21/31116 (2013.01) [H01J 37/32082 (2013.01); H01J 37/32449 (2013.01); H01L 21/02164 (2013.01); H01L 21/308 (2013.01); H01L 21/3065 (2013.01); H01L 21/31144 (2013.01); H01L 21/32136 (2013.01); H01L 21/32139 (2013.01); H01J 2237/334 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An etching method comprising:
forming a film on a surface of a substrate having a region at least partially made of silicon oxide and a mask provided on the region, the mask including an opening that partially exposes the region and the film being made of a same material as that of the region; and
after the forming the film, etching the region,
wherein the forming the film includes supplying a first gas to the substrate thereby forming a precursor layer on the substrate, and supplying a second gas to the precursor layer thereby forming the film from the precursor layer, wherein the precursor layer is formed with one of (1)-(5) conditions as indicated below,
wherein the film is configured such that a thickness thereof decreases from an upper end of the substrate along a depth direction of the opening of the mask and the region of the substrate is exposed at a bottom portion of the opening,
wherein, in the etching, the film corrects a shape of the mask to enhance a verticality of the opening formed in the region, and
wherein the (1)-(5) conditions are as follows:
(1) a pressure in the chamber during forming the precursor with the first gas is set to be less than a pressure at which a substance forming the precursor is adsorbed on an entire surface of the substrate,
(2) a processing time of forming the precursor with the first gas is set to be shorter than a process time in which the substance forming the precursor is adsorbed on the entire surface of the substrate,
(3) a dilution rate of the substance forming the precursor with the first gas is set to be lower than a dilution rate at which the substance forming the precursor layer is formed on the entire surface of the substrate,
(4) a temperature of a substrate support in the chamber is set to be lower than a temperature at which the substance forming the precursor with the first gas is adsorbed on the entire surface of the substrate, and
(5) an absolute value of a radio-frequency power is set to be smaller than an absolute value of the radio-frequency power at which the substance forming the precursor layer is adsorbed on the entire surface of the substrate.