Abstract:
A method for manufacturing semiconductor device. The method includes the steps of providing a substrate that has a gate structure thereon, and then forming offset spacers on the sidewalls of the gate structure. Thereafter, a thin oxide annealing operation is conducted, and then a first ion implantation is carried out using the gate structure and the offset spacers as a mask to form lightly doped drain regions in the substrate. Subsequently, secondary spacers are formed on the exterior sidewalls of the offset spacers. Finally, a second ion implantation is carried out using the gate structure, the offset spacers and the secondary spacers as a mask to form source/drain regions within the lightly doped drain regions.
Abstract:
A method for fabricating a metal-oxide semiconductor (MOS) transistor is provided. The method has steps of sequentially forming an oxide layer, a polysilicon layer and a cap layer on a semiconductor substrate to form a first-stage gate. An interchangeable source/drain region with a lightly doped drain (LDD) structure is formed in the substrate at each side of the first-stage gate. An insulating layer is formed over the substrate, and is planarized so as to exposed the cap layer. Removing the exposed cap layer forms an opening that exposes the polysilicon layer. Using the insulating layer as a mask, a self-aligned selective local implantation process is performed to form a threshold-voltage doped region and an anti-punch-through doped region below the oxide layer in the substrate. A conductive layer is formed over the substrate to fill the opening. A chemical mechanical polishing process is performed to expose the insulating layer so that a remaining portion of the conductive layer fills the opening to form together with the polysilicon layer and the oxide layer to serve as an gate structure.
Abstract:
A method of fabricating a metal oxide semiconductor includes formation of a gate on a substrate. A source/drain extension is formed beside the gate in the substrate. An ion implantation step is performed to implant heavy impurities with a low diffusion coefficient in the substrate. A heavily doped halo region is formed in the substrate below the source/drain extension. A tilt-angled halo implantation step is performed to form a halo-implanted region in the substrate to the side of the source/drain extension below the gate.
Abstract:
A method for manufacturing spacers comprising the steps of first providing a semiconductor substrate having a gate electrode already formed thereon, and then sequentially depositing oxide, silicon nitride and oxide over the gate electrode and the substrate to form a first oxide layer, a silicon nitride layer and a second oxide layer. Subsequently, the second oxide layer is etched to form an oxide spacer above the silicon nitride layer. Thereafter, using the oxide spacer as a mask, a dry etching method having a high etching selectivity ratio for silicon nitride/oxide is used to etch the silicon nitride layer to form a silicon nitride spacer. Finally, the oxide spacer is removed using an oxide dip method. The silicon nitride spacers of this invention can have a greater thickness, more thickness uniformity, and a higher reliability for hot carriers. In addition, the method used in the invention can have a better control over the thickness.
Abstract:
The process includes the following steps. At first, a masking layer is formed over the semiconductor substrate. A portion of the masking layer is then removed to form an opening to the semiconductor substrate. Sidewall spacers are formed on the opening and a portion of the semiconductor substrate is removed to form a trench, through an aperture defined by the sidewall spacers. The sidewall spacers is then removed and a liner layer is formed conformably over the trench.
Abstract:
A method of manufacturing a complementary metal-oxide-semiconductor that utilizes a slight change in the patterned photoresist layer for forming the lightly doped drain structure of an NMOS and the halo implantation region during CMOS fabrication. By forming a photoresist layer that exposes the p-well region where a well pickup structure is to be formed, the distance between the photoresist layer and the gate is increased, thereby eliminating the restrictions imposed upon the tilt angle in a halo implantation. Later, the lightly doped n-type impurities in the well pickup region can be compensated for by the p-type impurity implantation when the PMOS source/drain regions are formed. Hence, the lightly doped n-type well pickup region can be reverted to a p-type impurity doped region.
Abstract:
A semiconductor device comprises a semiconductor substrate, a source/drain region formed in the substrate, a gate oxide layer on the substrate between the source/drain region, a conductive layer on the gate oxide layer, a spacer around a side wall of the gate, and an air gap between the gate and the spacer. The spacer is not directly connected with the gate. The air gap is formed between the gate and the spacer.
Abstract:
A fabricating method and a structure of a stacked-type capacitor is provided comprising forming a first dielectric layer having a first via on a semiconductor substrate. A first conductive layer is filled into the first via. Then, insulating layers and dielectric layers are formed. A photolithography step is used to form a second dendriform via in the insulating layers and the dielectric layers. A second conductive layer is filled in the second dendriform via. The insulating layers and conductive layers are removed to form a dendriform lower electrode. The dendriform electrode provides a larger surface area to increase capacitance. Further, a polysilicon layer of hemispherical grains is formed to increase the surface area of the lower electrode.
Abstract:
A method of forming a self-aligned salicide is provided. The invention twice performs selective epitaxial growth to form an amorphous silicon layer on gate electrodes and source/drain regions of a substrate after forming the gate electrodes and the source/drain regions. Then, a molybdenum impurity is doped to perform a silicidation process and to convert a metal deposited on the substrate into a salicide layer.
Abstract:
Silicidation of a polysilicon line having frcc upper sidewalls is performed so that no stress is applied to the sidewalls of the polysilicon line, resulting in the formation of a reduced stress silicide structure. This is accomplished by forming a polysilicon line having spacers on either side which extend above the upper surface of the polysilicon line but which are spaced from the edge of the polysilicon line. A layer of a metal such as titanium or tungsten is provided in contact with the top surface polysilicon line. The structure is annealed to cause the metal to react with the polysilicon to form a layer of silicide. Since the upper side portions of the polysilicon line are spaced away from the spacers during the silicidation anneal, the growing silicide region has room to expand without being subjected to lateral stresses in the silicidation process. The suicide is formed in a reduced stress condition, as compared to conventional processes, so that the silicide layer produced will be more readily converted to the desired low resistivity phase of silicide.