Lam Research Corporation

Chen-Wei Liang

Jengyi Yu

Samantha S H Tan

Alan John Jensen

Seongjun Heo

Richard Stephan Wise

Yang Pan

Boris Volosskiy

Liu Yang

Da Li

Ge Yuan

Andrew Liang

Tin oxide films are used as spacers and hardmasks in semiconductor device manufacturing. In one method, tin oxide layer (e.g., spacer footing) needs to be selectively etched in a presence of an exposed silicon-containing layer, such as SiOC, SiON, SiONC, amorphous silicon, SiC, or SiN. In order to reduce damage to the silicon-containing layer the process involves passivating the silicon-containing layer towards a tin oxide etch chemistry, etching the tin oxide, and repeating passivation and etch in an alternating fashion. For example, passivation and etch can be each performed between 2-50 times. In one implementation, passivation is performed by treating the substrate with an oxygen-containing reactant, activated in a plasma, and the tin oxide etching is performed by a chlorine-based chemistry, such as using a mixture of Cland BCl.

Alternating etch and passivation process

Provided herein are methods and systems for reducing roughness of an EUV resist and improving etched features. The methods involve descumming an EUV resist, filling divots of the EUV resist, and protecting EUV resists with a cap. The resulting EUV resist has smoother features and increased selectivity to an underlying layer, which improves the quality of etched features. Following etching of the underlying layer, the cap may be removed.

Atomic layer etch and selective deposition process for extreme ultraviolet lithography resist improvement

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El Cerrito, CA, United States of America

Chen-Wei Liang