Abstract: Isotropic deposition of a selectively etchable material in an opening in a body of material followed by isotropic deposition of an etch resistant material forms a mask for anisotropic etching of the selectively etchable material at potentially sub-lithographic dimensions to form potentially sub-lithographic features within a trench. This process can be exploited to form a folded trench capacitor in which a trench is formed with one or more upstanding and possibly hollow features therein; effectively multiplying the surface area and or allowing reduced trench depth for a given charge storage capacity or a combination thereof. Further surface treatments such as deposition of hemispherical grain silicon can be used to further enhance the effective area of the trench. Isolation structures of sub-lithographic dimensions can also be formed by depositing appropriate materials within the trenches formed in accordance with the mask.

Abstract: The processing of a semiconductor body front side surface can be monitored in-situ, and thickness data for a body can be obtained ex-situ, by directing an infrared beam at the back side surface of the body. The light is reflected from front and back sides of a body portion to form primary and secondary reflections which are detected. An interference signal representative of interference fringes of the primary and secondary reflections is generated, and thickness data for the body or a body portion is calculated from the interference signal. In-situ monitoring of processes such as mechanical-chemical polishing, chemical vapor deposition, and plasma or reactive ion etching is achieved by providing a light passageway through a semiconductor body support such as a chuck or electrode, e.g., a cathode. In this manner, the process monitoring does not hinder, and is not hindered by, the processing steps and equipment.

Abstract: Isotropic deposition of a selectively etchable material in an opening in a body of material followed by isotropic deposition of an etch resistant material forms a mask for anisotropic etching of the selectively etchable material at potentially sub-lithographic dimensions to form potentially sub-lithographic features within a trench. This process can be exploited to form a folded trench capacitor in which a trench is formed with one or more upstanding and possibly hollow features therein; effectively multiplying the surface area and or allowing reduced trench depth for a given charge storage capacity or a combination thereof. Further surface treatments such as deposition of hemispherical grain silicon can be used to further enhance the effective area of the trench. Isolation structures of sub-lithographic dimensions can also be formed by depositing appropriate materials within the trenches formed in accordance with the mask.