| abstract |
Tin oxide films are used as spacers and hard masks in the manufacture of semiconductor devices. In one method, the tin oxide layer is conformally formed on the sidewalls and horizontal surfaces of the raised features on the substrate. Then, a passivation layer is formed over the tin oxide on the sidewall, and then the tin oxide is removed from the horizontal surface of the raised feature without removing the tin oxide at the sidewall of the raised feature. Then, the material of the raised feature is removed while leaving the tin oxide at the sidewall of the raised feature, thereby forming a tin oxide spacer. The chemical composition of dry etching based on hydrogen and chlorine is used to selectively etch tin oxide in the presence of many materials. In another method, the patterned tin oxide hard mask layer is formed on a substrate by forming a patterned layer over an unpatterned tin oxide and transferring the pattern to the tin oxide. |