Abstract:
PROBLEM TO BE SOLVED: To prevent resistance of an embedded strap of a DRAM cell from changing by the overlapping manner of a deep trench and an active region. SOLUTION: This semiconductor device contains a semiconductor substrate. At least a pair of deep trenches are formed in the substrate. A collar is formed in at least a part of the sidewall of each of the deep trenches. The inside of each of the deep trenches is filled with a trench filler 44. An embedded strap 46 is formed over the whole of each of the deep trenches and covers the upper surfaces of the trench filler 44 and the collar. An insulating region is formed between a a pair of the deep trenches. A trench upper part dielectric region 52 formed in the deep trench, so as to overlap with the embedded strap 46 of each of the deep trenches.
Abstract:
A structure and process for fabricating embedded vertical DRAM cells includes fabricating vertical MOSFET DRAM cells with silicided polysilicon layers in the array regions, the landing pad and/or interconnect structures, the support source and drain regions and/or the gate stack. The process eliminates the need for a M0 metallization layer.
Abstract:
A structure and process for fabricating embedded vertical DRAM cells includes fabricating vertical MOSFET DRAM cells with silicided polysilicon layers in the array regions, the landing pad and/or interconnect structures, the support source and drain regions and/or the gate stack. The process eliminates the need for a M0 metallization layer.
Abstract:
A method for clearing an isolation collar (5) 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 insulating material is deposited above a node conductor (3) of the storage capacitor. A layer of silicon (9) is deposited over the barrier material. Dopant ions are implanted at an angle (11) 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.
Abstract:
A method of forming relatively thin uniform insulating collar in the storage trench of a storage trench DRAM cell. A DRAM trench is first formed in a silicon substrate. Then, a nitride liner (81) is deposited on the silicon trench walls. The nitride liner may be deposited directly on the silicon walls or on an underlying oxide layer (79). A layer of amorphous silicon (83) is then deposited over the nitride liner. A silicon nitride layer is deposited on the oxidized surface of the amorphous silicon. A resist (83) is formed in the lower portion of the trench, and the exposed silicon nitride layer on top of the amorphous silicon is removed, leaving the upper portion of the amorphous silicon layer exposed. The upper portion of the layer of amorphous silicon is then oxidized so as to form a relatively thin, uniform collar (89) along the entire circumference of the trench. The nitride liner underlying the amorphous silicon layer enhances the thickness uniformity of the amorphous silicon layer and thereby the uniformity of the resulting oxide collar. The nitride liner also acts to limit lateral oxidation of the silicon trench walls during oxidation of the amorphous silicon layer. The nitride liner underlying the collar is also effective in cell operation to control the cell charge at the collar-substrate interface.
Abstract:
Vertical field effect transistors having a channel region defined by at least one semiconducting nanotube and methods for fabricating such vertical field effect transistors by chemical vapor deposition using a spacer-defined channel. Each nanotube is grown by chemical vapor deposition catalyzed by a catalyst pad positioned at the base of a high-aspect-ratio passage defined between a spacer and a gate electrode. Each nanotube grows in the passage with a vertical orientation constrained by the confining presence of the spacer. A gap may be provided in the base of the spacer remote from the mouth of the passage. Reactants flowing through the gap to the catalyst pad participate in nanotube growth.
Abstract:
Carbon nanotube field effect transistors, arrays of carbon nanotube field effect transistors, device structures, and arrays of device structures. A stacked device structure includes a gate electrode layer and catalyst pads each coupled electrically with a source/drain contact. The gate electrode layer is divided into multiple gate electrodes and at least one semiconducting carbon nanotube is synthesized by a chemical vapor deposition process on each of the catalyst pads. The gate electrode has a sidewall covered by a gate dielectric and at least one semiconducting carbon nanotube adjacent to the sidewall of the gate electrode. Source/drain contacts are electrically coupled with opposite ends of the semiconducting carbon nanotube to complete the device structure. Multiple device structures may be configured either as a memory circuit or as a logic circuit.
Abstract:
A structure and process for semiconductor fuses and antifuses in vertical DRAMS provides fuses and antifuses in trench openings formed within a semiconductor substrate. Vertical transistors may be formed in other of the trench openings formed within the semiconductor substrate. The fuse is formed including a semiconductor plug (108) formed within an upper portion of the trench opening (110) and includes conductive leads (252, 254) contacting the semiconductor plug. The antifuse is formed including a semiconductor plug formed within an upper portion of the trench opening and includes conductive leads formed over the semiconductor plug, at least one conductive lead isolated from the semiconductor plug by an antifuse dielectric. Each of the fuse and antifuse are fabricated using a sequence of process operations also used to simultaneously fabricate vertical transistors according to vertical DRAM technology, the plug forming the gate of the vertical transistor.
Abstract:
A semiconductor device including a substrate. At least one pair of deep trenches is arranged in the substrate. A collar lines at least a portion of a wall of each deep trench. A deep trench fill fills each deep trench. A buried strap extends completely across each deep trench over each deep trench fill and each collar. An isolation region is arranged between the deep trenches. A dielectric region overlies each buried strap in each deep trench.