Abstract:
A semiconductor structure and methods for forming the same are provided. The semiconductor structure includes a first MOS device of a first conductivity type and a second MOS device of a second conductivity type opposite the first conductivity type. The first MOS device includes a first gate dielectric on a semiconductor substrate; a first metal-containing gate electrode layer over the first gate dielectric; and a silicide layer over the first metal-containing gate electrode layer. The second MOS device includes a second gate dielectric on the semiconductor substrate; a second metal-containing gate electrode layer over the second gate dielectric; and a contact etch stop layer having a portion over the second metal-containing gate electrode layer, wherein a region between the portion of the contact etch stop layer and the second metal-containing gate electrode layer is substantially free from silicon.
Abstract:
A method of integrated circuit fabrication includes first forming at least one via in an insulting layer, and thereafter forming at least one trench-like structure separately. After a via is formed in an insulating layer, a layer of resist material is formed on the surface of the insulting layer and substantially filled the via. This step is followed by patterning at least one trench-like structure on the resist layer, and the trench-like structure is etched to the desired level. In some other embodiments, at least one trench-like structure is formed before at least one via is formed. An integrated circuit is manufactured by the aforementioned methods.
Abstract:
In accordance with the objective of the invention a new method is provided for the creation of a seal ring having dissimilar elements. The Critical Dimensions of the seal ring are selected with respect to the CD of other device features, such a seal vias, such that the difference in etch sensitivity between the created seal ring and the via holes is removed. All etch of the simultaneously etched features is completed at the same time, avoiding punch through of an underlying layer of etch stop material.
Abstract:
A method of fabrication used for semiconductor integrated circuit devices to define a thin copper fuse at a top via opening, in a partial etch, dual damascene integration scheme, efficiently reducing top metal thickness in a fusible link, for the purpose of laser ablation. Some advantages of the method are: (a) avoids copper fuse contact to low dielectric material, which is subject to the thermal shock of laser ablation, (b) increases insulating material thickness over the fuse using better thickness control, and most importantly, (c) reduces the copper fuse thickness, for easy laser ablation of the copper fuse, and finally, (d) uses USG, undoped silicate glass to avoid direct contact with low dielectric constant materials.
Abstract:
A process for creating a metal filled, dual damascene opening, in a composite insulator layer, has been developed. The process features selective RIE procedures, used to create a wide diameter opening in an upper silicon oxide layer, and a narrow diameter opening in a lower silicon oxide layer. Small area, silicon nitride islands, or shapes, a component of the composite insulator layer, are used as a stop layer, during the selective RIE procedures. The use of small area, silicon nitride shapes, offers less composite insulator capacitance, than counterparts fabricated using larger area, silicon nitride stop layers.
Abstract:
The present invention discloses a hybrid polysilicon/amorphous silicon TFT device for switching a LCD and a method for fabrication wherein a n.sup.+ doped amorphous silicon layer is advantageously used as a mask during a laser annealing process such that only a selected portion of a hydrogenated amorphous silicon layer is converted to a crystalline structure while other portions retain their amorphous structure. As a result, a polysilicon TFT and at least one amorphous silicon TFT are formed in the same structure and the benefits of both a polysilicon TFT and amorphous silicon TFT such as a high charge current and a low leakage current are retained in the hybrid structure.
Abstract:
The present invention includes forming a conductive layer on a substrate. Portions of the conductive layer are removed using a first photoresist layer as a mask. A first oxide layer is formed over the conductive layer and the substrate, and an amorphous silicon layer is then formed on the first oxide layer. After annealing the amorphous silicon layer, thereby transforming amorphous silicon layer to a polysilicon layer, a second oxide layer is formed on the polysilicon layer. The second oxide layer is removed using a second photoresist layer as a mask. An amorphous silicon carbon layer is formed over the second oxide layer and the polysilicon layer, and a heavily-doped amorphous silicon carbon layer is formed on the amorphous silicon carbon layer. After annealing the heavily-doped amorphous silicon carbon layer and the amorphous silicon carbon layer, thereby transforming the heavily-doped amorphous silicon carbon layer to a heavily-doped polysilicon carbon layer, and transforming the amorphous silicon carbon layer to a polysilicon carbon layer, portions of the polysilicon carbon layer, the heavily-doped polysilicon carbon layer and the polysilicon layer are removed using a third photoresist layer as a mask.
Abstract:
A method of fabricating a polycrystalline silicon thin-film transistor having two symmetrical lateral resistors is disclosed. Two sub-gates are formed along with a gate in the gate metal or polysilicon layer of the thin-film transistor. The two sub-gates that are located symmetrically on the two sides of the gate have equal distances to the gate. One sub-gate is near the drain of the thin film transistor and the other near the source. Two sections in the polycrystalline silicon layer of the thin film transistor are blocked by the two sub-gates and no impurity material is doped. The two undoped sections form the symmetrical lateral resistors of this invention. The lateral resistor near the drain decreases the electric field in the nearby depletion area when the thin-film transistor is switched off. The current leakage is reduced.