Patent attributes
Tin oxide films are used as spacers and hardmasks in semiconductor device manufacturing. In one method, tin oxide layer is formed conformally over sidewalls and horizontal surfaces of protruding features on a substrate. A passivation layer is then formed over tin oxide on the sidewalls, and tin oxide is then removed from the horizontal surfaces of the protruding features without being removed at the sidewalls of the protruding features. The material of the protruding features is then removed while leaving the tin oxide that resided at the sidewalls of the protruding features, thereby forming tin oxide spacers. Hydrogen-based and chlorine-based dry etch chemistries are used to selectively etch tin oxide in a presence of a variety of materials. In another method a patterned tin oxide hardmask layer is formed on a substrate by forming a patterned layer over an unpatterned tin oxide and transferring the pattern to the tin oxide.
