摘要:
The vertical DRAM capacitor with a buried LOCOS collar characterized by: a self-aligned bottle and gas phase doping; no consumption of silicon at the depth of the buried strap; no reduction of trench diameter; and a nitride layer to protect trench sidewalls during gas phase doping.
摘要:
A process for fabricating a single-sided semiconductor deep trench structure filled with polysilicon trench fill material includes the following steps. Form a thin film, silicon nitride, barrier layer over the trench fill material. Deposit a thin film of an amorphous silicon masking layer over the barrier layer. Perform an angled implant into portions of the amorphous silicon masking layer which are not in the shadow of the deep trench. Strip the undoped portions of the amorphous silicon masking layer from the deep trench. Then strip the newly exposed portions of barrier layer exposing a part of the trench fill polysilicon surface and leaving the doped, remainder of the amorphous silicon masking layer exposed. Counterdope the exposed part of the trench fill material. Oxidize exposed portions of the polysilicon trench fill material, and then strip the remainder of the masking layer.
摘要:
The surface area of the walls of a trench formed in a substrate is increased. A barrier layer is formed on the walls of the trench such that the barrier layer is thinner near the corners of the trench and is thicker between the corners of the trench. A dopant is introduced into the substrate through the barrier layer to form higher doped regions in the substrate near the corners of the trench and lesser doped regions between the corners of the trench. The barrier layer is removed, and the walls of the trench are etched in a manner that etches the lesser doped regions of the substrate at a higher rate than the higher doped regions of the substrate to widen and lengthen the trench and to form rounded corners at the intersections of the walls of the trench.
摘要:
A method for clearing an isolation collar from a first interior surface of a deep trench at a location above a storage capacitor while leaving the isolation collar at other surfaces of the deep trench. A barrier material is deposited above a node conductor of the storage capacitor. A layer of silicon is deposited over the barrier material. Dopant ions are implanted at an angle into the layer of deposited silicon within the deep trench, thereby leaving the deposited silicon unimplanted along one side of the deep trench. The unimplanted silicon is etched. The isolation collar is removed in locations previously covered by the unimplanted silicon, leaving the isolation collar in locations covered by the implanted silicon.
摘要:
A trench capacitor structure for improved charge retention and method of manufacturing thereof are provided. A trench is formed in a p-type conductivity semiconductor substrate. An isolation collar is located in an upper portion of the trench. The substrate adjacent the upper portion of the trench contains a first n+ type conductivity region and a second n+ type conductivity region. These regions each abut a wall of the trench and are separated vertically by a portion of the p-type conductivity semiconductor substrate. A void which encircles the perimeter of the trench is formed into the wall of the trench and is located in the substrate between the first and second n+ type conductivity regions.
摘要:
A trench capacitor with improved strap is disclosed. The strap is located above the top surface of the capacitor. The top surface of the trench capacitor, which is formed by the top surfaces of the collar and storage plate, is planar. By locating the strap on a planar surface, the divot present in conventional strap processes is avoided. This results in improved strap reliability and device performance.
摘要:
A trench capacitor with improved strap is disclosed. The strap is located above the top surface of the capacitor. The top surface of the trench capacitor, which is formed by the top surfaces of the collar and storage plate, is planar. By locating the strap on a planar surface, the divot present in conventional strap processes is avoided. This results in improved strap reliability and device performance.
摘要:
A trench capacitor with improved strap is disclosed. The strap is located above the top surface of the capacitor. The top surface of the trench capacitor which is formed by the top surfaces of the collar and storage plate, is planar. By locating the strap on a planar surface, the divot present in conventional strap processes is avoided. This results in improved strap reliability and device performance.
摘要:
An improved capacitor is formed by a process where an improved node dielectric layer is formed with an improved dielectric constant by performing an Free Radical Enhanced Rapid Thermal Oxidation (FRE RTO) step during formation of the node dielectric layer. Use of an FRE RTO step instead of the conventional furnace oxidation step produces a cleaner oxide with a higher dielectric constant and higher capacitance. Other specific embodiments of the invention include improved node dielectric layer by one or more additional nitridation steps, done by either Remote Plasma Nitridation (RPN), Rapid Thermal Nitridation (RTN), Decoupled Plasma Nitridation (DPN) or other nitridation method; selective oxidation; use of a metal layer rather than a SiN layer as the dielectric base; and selective oxidation of the metal layer.