Abstract: One aspect of the invention relates to a method of manufacturing an integrated circuit comprising forming an array of ferroelectric memory cells on a semiconductor substrate, heating the substrate to a temperature near a Curie temperature of the ferroelectric cores, and subjecting the substrate to a temperature program, whereby thermally induced stresses on the ferroelectric cores cause a switched polarization of the cores to increase by at least about 25% as the cores cool to about room temperature. Embodiments of the invention include metal filled vias of expanded cross-section above and below the ferroelectric cores, which increase the thermal stresses on the ferroelectric cores during cooling.

Abstract: One aspect of the invention relates to a method of manufacturing an integrated circuit comprising forming an array of ferroelectric memory cells on a semiconductor substrate, heating the substrate to a temperature near a Curie temperature of the ferroelectric cores, and subjecting the substrate to a temperature program, whereby thermally induced stresses on the ferroelectric cores cause a switched polarization of the cores to increase by at least about 25% as the cores cool to about room temperature. Embodiments of the invention include metal filled vias of expanded cross-section above and below the ferroelectric cores, which increase the thermal stresses on the ferroelectric cores during cooling.

Abstract: Methods (100) are provided for fabricating a ferroelectric capacitor structure including methods (128) for etching and cleaning patterned ferroelectric capacitor structures in a semiconductor device. The methods comprise etching (140, 200) portions of an upper electrode, etching (141, 201) ferroelectric material, and etching (142, 202) a lower electrode to define a patterned ferroelectric capacitor structure, and etching (143, 206) a portion of a lower electrode diffusion barrier structure. The methods further comprise ashing (144, 203) the patterned ferroelectric capacitor structure using a first ashing process, performing (145, 204) a wet clean process after the first ashing process, and ashing (146, 205) the patterned ferroelectric capacitor structure using a second ashing process directly after the wet clean process at a high temperature in an oxidizing ambient.

Abstract: Semiconductor devices and fabrication methods are presented, in which a hydrogen barrier is provided above a ferroelectric capacitor to prevent degradation of the ferroelectric material during back-end manufacturing processes employing hydrogen. The hydrogen barrier comprises silicon rich silicon oxide or amorphous silicon, which can be used in combination with an aluminum oxide layer to inhibit diffusion of process-related hydrogen into the ferroelectric capacitor layer.

Abstract: The present invention is directed to a method of forming an FeRAM integrated circuit, which includes forming a multi-layer hard mask. The multi-layer hard mask comprises a hard masking layer overlying an etch stop layer. The etch stop layer is substantially more selective than the overlying masking layer with respect to an etch employed to remove the bottom electrode diffusion barrier layer. Therefore during an etch of the capacitor stack, an etch of the bottom electrode diffusion barrier layer results in a substantially complete removal of the hard masking layer. However, due to the substantial selectivity (e.g., 10:1 or more) of the etch stop layer with respect to the overlying masking layer, the etch stop layer completely protects the underlying top electrode, thereby preventing exposure thereof.

Abstract: The present invention is directed to a method of forming an FeRAM integrated circuit, which includes forming a TiAlON bottom electrode diffusion barrier layer prior to formation of the bottom electrode layer in an FeRAM capacitor stack. Subsequently, when performing the capacitor stack etch, the portion of the TiAlON diffusion barrier layer not covered by the FeRAM capacitor stack is etched substantially anisotropically due to the oxygen within the TiAlON diffusion barrier layer substantially preventing a lateral etching thereof. In the above manner, an undercut of the TiAlON diffusion barrier layer under the FeRAM capacitor stack is prevented. In another aspect of the invention, a method of forming an FeRAM capacitor comprises forming a multi-layer bottom electrode diffusion barrier layer. Such formation comprises forming a TiN layer over the interlayer dielectric layer and the conductive contact and forming a diffusion barrier layer thereover.

Abstract: One aspect of the invention relates to a method of manufacturing a semiconductor device in which an alignment mark is formed by a plurality of adjacent filled trenches. A processing tool detects the trenches as though they were a single filled trench of larger dimension. When the trenches are metal filled, the metal is more easily protected from oxidation than when the metal is formed into a single large trench, an effect that is pronounced when the trenches are filled with tungsten. Another aspect of the invention relates to an alignment mark formed by a plurality of tungsten filled trenches. The alignment mark can be used to align the pattern for an FeRAM capacitor stack to underlying tungsten contacts.

Abstract: A method of fabricating a ferroelectric capacitor is disclosed. The method comprises the patterning of a top electrode layer and a dielectric layer to form a capacitor stack structure having sidewalls associated therewith. Prior to patterning the bottom electrode layer, a protective film is formed on the sidewalls of the capacitor stack structure in order to protect the dielectric material from conductive contaminants associated with a subsequent patterning of the bottom electrode layer.

Abstract: A method of fabricating a ferroelectric capacitor is disclosed. The method comprises the patterning of a top electrode layer and a dielectric layer to form a capacitor stack structure having sidewalls associated therewith. Prior to patterning the bottom electrode layer, a protective film is formed on the sidewalls of the capacitor stack structure in order to protect the dielectric material from conductive contaminants associated with a subsequent patterning of the bottom electrode layer.