Abstract:
A DRAM cell and method of fabrication are provided that eliminate critical photolithography fabrication steps by merging stacked capacitor formation with electrical contacts. The a single lithography step can be used to form the electrical contacts (28) because the stacked capacitors (46,48,50) are co-planar with the bit lines (36) and the stacked capacitors are located in the insulating material provided between the bit lines. Unlike conventional capacitor-over-bit line (COB) DRAM cells, this capacitor-beside-bit line DRAM cell eliminates the need to dedicate contacts to the capacitor, making it possible to achieve higher capacitance with lower global topography.
Abstract:
A semiconductor device, in accordance with the present invention, includes a doped semiconductor substrate (102) wherein the doping of the substrate has a first conductivity and a device region (110) formed near a surface of the substrate. The device region includes at least one device well. A buried well (104) is formed in the substrate below the device region. The buried well is doped with dopants having a second conductivity. A trench region (124) surrounds the device region and extends below the surface of the substrate to at least the buried well such that the device region is isolated from other portions of the substrate by the buried well and the trench region.
Abstract:
A DRAM cell and method of fabrication are provided that eliminate critical photolithography fabrication steps by merging stacked capacitor formation with electrical contacts. The a single lithography step can be used to form the electrical contacts because the stacked capacitors are co-planar with the bit lines and the stacked capacitors are located in the insulating material provided between the bit lines. Unlike conventional capacitor-over-bit line (COB) DRAM cells, this capacitor-beside-bit line DRAM cell eliminates the need to dedicate contacts to the capacitor, making it possible to achieve higher capacitance with lower global topography.
Abstract:
A semiconductor memory device (100), in accordance with the present invention, includes a substrate having a major surface including an array region (102) and a support region (104). The array region includes memory cell structures (106) having a first height above the major surface of the substrate. The support area includes dummy structures (119) formed therein having a second height above the major surface. A dielectric layer (118) is formed over the memory cell structures in the array region and the dummy structures in the support region such that a top surface (122) of the dielectric layer is substantially planar wherein topographical features are substantially eliminated on the dielectric layer across the array region and the support region.
Abstract:
Apparatus for etching a patterned layer of a noble metal such as platinum. The apparatus implements a process whereby exposed areas of the noble metal are first implanted with ions and are subsequently etched. Both the ion implantation step and the etching step occur sequentially in the same chamber in the presence of a plasma discharge. The apparatus uses either a dual output power supply or two distinct power supplies to sequentially supply a high power output required for the ion implantation step and a low power output required for the etching step. Multiple cycles of implantation followed by etching may be applied to achieve deep etching of thick layers. A programmed computer controls the process steps. A method of using the apparatus is also provided.