Abstract: A method of fabricating a barrier layer includes oxidizing a silicon-containing substrate to form a substrate oxide layer on the surface of the substrate, producing an oxygen-impervious layer at an interface between the substrate oxide layer and the substrate, and etching the substrate oxide layer until the underlying oxygen-impervious layer is uncovered.

Abstract: A memory cell has a trench, in which a trench capacitor is disposed. Furthermore a vertical transistor is formed in the trench above the trench capacitor. A barrier layer is disposed for the electric connection of the conductive trench filling to a lower doping region of the vertical transistor. The barrier layer is a diffusion barrier for dopants or impurities that are contained in the conductive trench filling.

Abstract: In a method for forming a trench capacitor a first layer of silicon oxide is deposited in a storage trench and a layer of silicon is deposited over the first layer by a chemical vapor deposition process. A layer of an oxidizable metal is deposited over the layer of silicon. The layer of silicon and the layer of the oxidizable metal are subsequently oxidized to form a layer of silicon oxide and metal oxide.

Abstract: A method in which a recess is formed in the surface of a semiconductor substrate and a material is grown on the inner wall of the recess, includes the steps of producing an electrically insulating layer on the surface of the substrate outside the recess, and selectively growing the material on the inner wall of the recess as a result of the substrate, as an electrode, being brought into contact with an electrolysis liquid and electrolysis being carried out, during which the insulating layer prevents the material from growing outside the recess. Before the electrolysis is carried out, a reserve material is epitaxially deposited on the inner wall of the recess and, during the electrolysis, the reserve material is converted into the material being grown by electrolysis.

Abstract: A memory having a memory cell formed in a substrate and including a trench capacitor and a transistor and a method for producing the memory includes connecting the trench capacitor to the transistor with a self-aligned connection. The transistor at least partly covers the trench capacitor. The trench capacitor is filled with a conductive trench filling and an insulating covering layer is situated on the conductive trench filling. An epitaxial layer is situated above the insulating covering layer. The transistor is formed in the epitaxial layer. The self-aligned connection is formed in a contact trench and includes an insulation collar in which a conductive material is introduced. A conductive cap is formed on the conductive material.

Abstract: A trench capacitor has an insulation collar that is formed non-conformally in the upper region of a trench in such a way that a layer thickness in an upper section of the insulation collar is greater than a layer thickness in a lower section of the insulation collar. This results in a trench capacitor having improved leakage current properties. A simplified and cost-effective method of fabricating a trench capacitor is also provided.

Abstract: A semiconductor memory cell is formed in a substrate and includes a trench capacitor and a selection transistor. The trench capacitor includes a capacitor dielectric and a conductive trench filling. Disposed on the conductive trench filling is a diffusion barrier on which an epitaxial layer is formed. The selection transistor is disposed as a planar transistor above the trench capacitor. A drain doping region of the selection transistor is disposed in the epitaxial layer.

Abstract: A trench capacitor for use in a semiconductor memory cell is formed in a substrate. The trench capacitor includes a trench having an upper region and a lower region, an insulation collar formed in the upper region on a trench wall of the trench, and a buried well, through which the lower region of the trench at least partly extends. The trench capacitor further includes, as an outer capacitor electrode, a conductive layer lining the lower region of the trench and the insulation collar, a dielectric layer lining the conductive layer, and a conductive trench filling which is filled into the trench as an inner capacitor electrode. A method of fabricating a trench capacitor is also provided.

Abstract: A trench capacitor has an insulation collar that is formed non-conformally in the upper region of a trench in such a way that a layer thickness in an upper section of the insulation collar is greater than a layer thickness in a lower section of the insulation collar. This results in a trench capacitor having improved leakage current properties. A simplified and cost-effective method of fabricating a trench capacitor is also provided.

Abstract: A non-volatile semiconductor memory cell and an associated method are disclosed, in which a conventional dielectric ONO layer (10) is replaced by a very thin metal oxide layer (6) of WOx and/or TiO2. The high relative dielectric constant of these materials further improves the integration density and the control voltages required for the semiconductor memory cell.

Abstract: In a method for forming a trench capacitor a first layer of silicon oxide is deposited in a storage trench and a layer of silicon is deposited over the first layer by a chemical vapor deposition process. A layer of an oxidizable metal is deposited over the layer of silicon. The layer of silicon and the layer of the oxidizable metal are subsequently oxidized to form a layer of silicon oxide and metal oxide.

Abstract: A trench capacitor is formed in a substrate and includes a trench having an upper region and a lower region. An insulating collar is formed in the upper region of the trench. The lower region of the trench extends through a buried well. A buried plate is formed around the lower region of the trench as an outer capacitor electrode. A dielectric layer, which forms the capacitor dielectric, lines the lower region of the trench and the insulating collar. A conductive trench filling is put into the trench. A conductive contact layer of tungsten nitride is provided above the insulating collar, between the substrate and the conductive trench filling, and acts as a diffusion barrier. This makes it possible to provide the trench capacitor more closely to the transistor, since the transistor is not damaged by material which is contained in the conductive trench filling.

Abstract: To fabricate a trench capacitor in a substrate, a trench is formed in the substrate. The trench has an upper region and a lower region. In the trench, first of all nanocrystallites and/or a seed layer for nanocrystallites are deposited in the upper region and the lower region. Then, the nanocrystallites and/or the seed layer are removed from the upper region of the trench by means of an etching process. The etching parameters of the etching process are selected in such a way that the seed layer and/or the nanocrystallites which are uncovered in the upper region and the lower region are removed only from the upper region. Consequently, an expensive mask layer can be avoided in the lower region of the trench.

Abstract: A two-step progressive thermal oxidation process is provided to improve the thickness uniformity of a thin oxide layer in semiconductor wafer fabrication. A semiconductor wafer, e.g., of silicon, with a surface subject to formation of an oxide layer thereon but which is substantially oxide layer-free, is loaded, e.g., at room temperature, into an oxidation furnace maintained at a low loading temperature, e.g., of 400-600° C., and the wafer temperature is adjusted to a low oxidizing temperature, e.g., of 400-600° C., all while the wafer is under an inert, e.g., nitrogen, atmosphere. The wafer is then subjected to initial oxidation, e.g., in dry oxygen, at the low oxidizing temperature to form a uniform initial thickness oxide, e.g., silicon dioxide, layer, e.g., of up to 10 angstroms, on the surface, after which the furnace temperature is increased to a high oxidizing temperature, e.g., of 700-1200° C., while the wafer is under an inert atmosphere. The wafer is next subjected to final oxidation, e.

Abstract: A method for manufacturing a trench capacitor uses a low-pressure gas phase doping for forming a buried plate as a capacitor plate. The use of the low-pressure gas phase doping reduces process costs and improves capacitor properties.

Abstract: A method in which a recess is formed in the surface of a semiconductor substrate and a material is grown on the inner wall of the recess, includes the steps of producing an electrically insulating layer on the surface of the substrate outside the recess, and selectively growing the material on the inner wall of the recess as a result of the substrate, as an electrode, being brought into contact with an electrolysis liquid and electrolysis being carried out, during which the insulating layer prevents the material from growing outside the recess. Before the electrolysis is carried out, a reserve material is epitaxially deposited on the inner wall of the recess and, during the electrolysis, the reserve material is converted into the material being grown by electrolysis.

Abstract: A trench capacitor, in particular for use in a semiconductor memory cell, has a trench formed in a substrate; an insulation collar formed in an upper region of the trench; an optional buried plate in the substrate region serving as a first capacitor plate; a dielectric layer lining the lower region of the trench and the insulation collar as a capacitor dielectric; a conductive second filling material filled into the trench as a second capacitor plate; and a buried contact underneath the surface of the substrate. The substrate has, underneath its surface in the region of the buried contact, a doped region introduced by implantation, plasma doping and/or vapor phase deposition. A tunnel layer, in particular an oxide, nitride or oxinitride layer, is preferably formed at the interface of the buried contact.

Abstract: A trench is formed in a substrate with an upper region and a lower region. The trench is subsequently widened in its upper region and in its lower region by isotropic etching. In the upper region, an insulating collar is formed that is designated as a buried insulating collar due to the widened trench. The insulating collar is removed in the vicinity of the surface of the substrate, through which the substrate is exposed in this region. Here, a selective epitaxial layer is subsequently grown in the trench, through which a subsequently formed selection transistor can be formed in perpendicular fashion over the trench, or very close to the trench. In addition, through the widened trench the electrode surface of the capacitor electrodes is enlarged, which ensures an increased storage capacity.

Abstract: A trench capacitor is formed with an insulation collar. After the formation of the trench, firstly an insulating layer is deposited, from which layer the insulation collar will be subsequently formed. Afterward, the trench is partly filled with a sacrificial filling material and a thin patterning layer is deposited thereon. Spacers are formed from that layer and cover the insulating layer in the upper region of the trench. Afterward, the sacrificial filling material and the insulating layer are completely removed in the lower region of the trench. As a result, the insulation collar is produced in the upper region of the trench.

Abstract: The instant invention is a method for fabricating a trench contact to a deep trench capacitor with a polysilicon filling in a trench hole formed in a silicon substrate. An epitaxy process is performed to selectively grow silicon above the polysilicon filling in the trench hole. An opening leading to the polysilicon filling is anisotropically etched into the epitaxially grown silicon. The opening has lateral dimensions that are smaller than those of the polysilicon filling, and the opening is filled with polysilicon.