Abstract: A method for forming a shallow-trench isolation starts with forming a polysilicon layer, which has less stress, as the mask layer for patterning the trench on a provided substrate. An oxide layer is then formed to cover the polysilicon layer and fill the trench. The oxide layer is then removed by first performing a chemical mechanical polishing process to remove a portion of the oxide layer, wherein the remains of the oxide layer still covers the polysilicon layer and fills the trench. After that, an etching back process is performed to remove the oxide layer from the top of the polysilicon layer to form the oxide plug, which is used as an isolation.

Abstract: A method for fabricating trench isolation structures using the reverse mask is described. The method of using a reverse mask to fabricate trench isolation structures includes providing a semiconductor substrate having a first trench and a second trench in the substrate. The first trench has a width smaller than a fixed value, while the second trench has a width larger than the fixed value, the fixed value being, for example, about 0.7 .mu.m. Thereafter, a conformal insulating layer is formed over the first trench and the second trench. Next, a reverse mask layer is formed over the conformal insulating layer, and then the reverse mask layer is patterned. The reverse mask layer is patterned selectively. For example, only the region directly above the second trench is covered by the reverse mask. The region directly above the first trench is exposed.

Abstract: An LDD source/drain region is manufactured adjacent a gate electrode using a single ion implantation step. The method begins by providing a polysilicon gate electrode on a gate oxide over a substrate and then providing a thin, layer of CVD oxide over the gate electrode and over the substrate. A thicker, second layer of a material different from the first silicon oxide layer is deposited over the device and is etched back to form sidewall spacer structures alongside and spaced slightly from the gate electrode. The spacer structures formed from the second layer are then used as a mask to etch the oxide layer where it is exposed over the active regions of the substrate and then the spacer structures are removed. The portion of the oxide layer that remains over the top and sides of the gate electrode and over portions of the substrate adjacent the gate electrode is then used as a mask for an ion implantation process.

Abstract: A method of making vias in a semiconductor IC device having adequate contact to the surface of the interconnects and without inadequate landing is disclosed. The method has interconnects formed in a metal layer on the substrate of the IC device, and a first dielectric layer is formed covering the surface of the interconnects. An etch-stopping layer is then formed on top of the first dielectric layer, followed by the formation of a second dielectric layer on top of the etch-stopping layer. A photoresist layer then covers the second dielectric layer and reveals the surface regions of the second dielectric layer designated for the formation of the vias. A main etching procedure is then performed to etch into the second dielectric layer down to the surface of the etch-stopping layer, thereby forming the first section of the vias.

Abstract: A method of chemical-mechanical polishing for forming a shallow trench isolation. A substrate having a plurality of active regions, including a large active region and a small active region, is provided. A silicon nitride layer is formed on the substrate. A shallow trench is formed between the active regions. An oxide layer is formed over the substrate, so that the shallow trench is filled therewith. A partial reverse active mask is formed on the oxide layer, so that the oxide layer on a central part of the large active region is exposed. Whereas, the oxide layer on an edge part of the large active region and on the small active region are covered by the partial reverse active mask. The oxide layer is etched with the silicon nitride layer as a stop layer, using the partial reverse active mask as a mask. The oxide layer is planarized until the oxide layer within the shallow trench has a same level as the silicon nitride layer.

Abstract: A method for fabricating a MOS transistor device is provided. The method contains sequentially forming an oxide layer, a polysilicon layer, and a cap layer over a semiconductor substrate. Patterning the oxide layer, the polysilicon layer, the cap layer, and the substrate forms a trench opening in the substrate. A shallow trench isolation (STI) structure is formed by filling the opening with insulating material. A first-stage gate structure is formed on the substrate by patterning the oxide layer, the polysilicon layer, and the cap layer. A top portion of the STI structure above the substrate surface is exposed. A light ion implantation is performed to form a lightly doped region. Several spacers are respectively formed on each sidewall of the first-stage gate structure and each exposed sidewall of the STI structure. A heavy ion implantation process is performed to form interchangeable source/drain regions at each side of the first-stage gate structure. The cap layer is removed to leave an opening.

Abstract: A shallow trench isolation process provides a high quality oxide on the substrate adjacent the trench and on the upper part of the trench. This process avoids the formation of poor quality oxide on the substrate adjacent the upper edge of the trench that is believed to cause MOS transistors to exhibit the undesirable subthreshold current flow known as the "kink" effect. A pad oxide layer is grown on the surface of a silicon substrate and then a layer of silicon nitride is formed on the surface of the pad oxide. A photoresist mask is formed over the silicon nitride and the silicon nitride and pad oxide are etched, and then the substrate is etched to form a trench. The photoresist mask is removed, a layer of polysilicon is deposited over the silicon nitride layer and within the trench and the polysilicon layer is oxidized. CVD oxide is deposited to overfill the trench and then the excess CVD oxide and polysilicon oxide is removed by CMP, using the silicon nitride layer as an polish stop.

Abstract: A method of fabricating a metal-oxide semiconductor (MOS) transistor is provided. This method is devised particularly to reduce the level of degradation to the MOS transistor caused by hot carriers. In the fabrication process, a plasma treatment is applied to the wafer to as to cause the forming of a thin layer of silicon nitride on the wafer which covers the gate and the lightly-doped diffusion (LDD) regions on the source/drain regions of the MOS transistor. This thin layer of silicon nitride acts as a barrier which prevents hot carriers from crossing the gate dielectric layer, such that the degradation of the MOS transistor due to hot carriers crossing the gate dielectric layer can be greatly minimized.

Abstract: A method of forming MOS components provides that after the formation of the gate and the doped source/drain regions, a polysilicon layer is deposited and planarized using a chemical-mechanical polishing method. The resulting unremoved polysilicon layer acts as source/drain terminals. Through these arrangements, the ion doped source/drain regions will have shallow junctions, yet their junction integrity will not be compromised by subsequent contact window etching and metallization processes. Furthermore, the front-end processes for forming the MOS component provide a good planar surface that offers great convenience for the performance of subsequent back-end processes.

Abstract: The present invention relates to a method of forming lightly doped drains in metallic oxide semiconductor (MOS) components. The method includes forming a first, second, and third insulating layer above a silicon substrate having a gate, etching back the layers to leave behind L-shaped first spacers on sidewalls of the gate, followed by doping second type ions into the silicon substrate to form first lightly doped drains in the silicon substrate surface below the L-shaped first spacers, and second lightly doped drains in the silicon substrate surface elsewhere, further forming a fourth insulating to form third spacers, and using the using the third spacers, the first insulating layer, and the gate as masks when doping second type ions into the silicon substrate so as to form source/drain regions in silicon substrate surfaces not covered by the third spacers. Such a method produces greater yield and reduces leakage current from the transistor components.