Abstract: A process is described for depositing silicon nitride, in which the temperature in a furnace is set to from 600° C. to 645° C. The silicon nitride formed in this way is permeable to small molecules, such as in particular hydrogen molecules, yet nevertheless retains its etching selectivity with respect to silicon dioxide.

Abstract: A method for fabricating a trench capacitor for a semiconductor memory includes forming a masking layer in a trench that is disposed in a substrate. Nanocrystallites, which are used to pattern the masking layer, are deposited on the masking layer. Microtrenches are etched into the substrate in a lower region of the trench by the patterned masking layer. The microtrenches form a roughened trench sidewall. As a result, the outer capacitor electrode is formed with a larger surface area, allowing the trench capacitor to have a higher capacitance.

Abstract: A method for improving a doping profile using gas phase doping is described. In the method, silicon nitride and/or products of decomposition from a silicon nitride deposition are introduced in a process chamber before or during the actual gas phase doping. This allows the doping profile to be significantly improved.

Abstract: A method for fabricating a trench capacitor for a semiconductor memory includes forming a masking layer in a trench that is disposed in a substrate. Nanocrystallites, which are used to pattern the masking layer, are deposited on the masking layer. Microtrenches are etched into the substrate in a lower region of the trench by the patterned masking layer. The microtrenches form a roughened trench sidewall. As a result, the outer capacitor electrode is formed with a larger surface area, allowing the trench capacitor to have a higher capacitance.

Abstract: A method for improving a doping profile using gas phase doping is described. In the method, silicon nitride and/or products of decomposition from a silicon nitride deposition are introduced in a process chamber before or during the actual gas phase doping. This allows the doping profile to be significantly improved.

Abstract: A method for fabricating a trench capacitor, that includes steps of: providing a silicon substrate; forming a trench, having a lower region and a surface, in the silicon substrate; and forming a doped layer in the silicon substrate in the lower region of the trench. In addition, a roughened silicon layer that has silicon grains with a diameter ranging from essentially 10 to 100 nm is produced in the lower region of the trench. A dielectric intermediate layer is applied on the roughened silicon layer, and the trench is filled with a doped layer.

Abstract: A microroughness on a surface is produced in a single process step by forming semiconductor grains directly from a process gas. The semiconductor grains are finely distributed on the surface. As a result of forming the microroughness in a single process step, time and costs are saved during fabrication.

Abstract: A method for fabricating a trench capacitor, that includes steps of: providing a silicon substrate; forming a trench, having a lower region and a surface, in the silicon substrate; and forming a doped layer in the silicon substrate in the lower region of the trench. In addition, a roughened silicon layer that has silicon grains with a diameter ranging from essentially 10 to 100 nm is produced in the lower region of the trench. A dielectric intermediate layer is applied on the roughened silicon layer, and the trench is filled with a doped layer.