Abstract: A method for developing a photo-exposed photoresist layer to improve a critical dimension uniformity (CDU) for a semiconductor device manufacturing process including providing a semiconductor process wafer having a process surface comprising a photoresist layer photo-exposed according to an exposure pattern; dispensing a predetermined amount of developer solution over a stationary semiconductor process wafer to form a film of developer solution covering the process surface; partially developing the exposed portions of the photoresist layer comprising maintaining the semiconductor process wafer in a stationary position for a predetermined time period; rotating the semiconductor process wafer for a predetermined period of time to remove a portion of the developer solution; and, repeating the steps of dispensing, partially developing, and rotating, for a predetermined number of repetition cycles to complete a photoresist development process.

Abstract: Removing photoresist from alignment marks on a semiconductor wafer using a wafer edge exposure process is disclosed. The alignment marks on the wafer are covered by photoresist used in conjunction with semiconductor processing of one or more layers deposited on the semiconductor wafer. One or more parts of the edge of the wafer are exposed to remove the photoresist from these parts and thus reveal alignment marks on the wafer. The exposure of the one or more parts of the wafer is accomplished without performing a photolithographic clear out process. Rather, a wafer edge exposure (WEE) process is inventively utilized. Once the WEE process is performed, subsequent layers may be deposited by aligning them using the revealed alignment marks.

Abstract: A method for fabricating capacitor-under-bit line (CUB) DRAMs with logic circuits is achieved. CUB are better than capacitor-over-bit line (COB) DRAM circuits because of reduced contact aspect ratios, but CUB require patterning the capacitor top plate over the capacitor rough topography while providing openings to bit line contacts between closely spaced capacitors. A bottom antireflecting coating (BARC) is used in a first method; a non-conform PECVD oxide is used in a second method to make reliable high aspect ratio openings between the capacitors. The BARC is deposited to fill the space between capacitors. A photo-resist layer with improved uniformity is then deposited over the BARC and exposed and developed to form an etch mask with improved resolution for the capacitor top plate. The BARC is plasma etched, and the polysilicon plate is patterned. In the second method a non-conformal PECVD oxide is deposited that is thicker on the top of the capacitors than in the narrow space between capacitors.

Abstract: A method using a single masking step for making double-cylinder stacked capacitors for DRAMs which increases capacitance while eliminating erosion of an underlying oxide insulating layer when the masking step is misaligned is described. A planar silicon oxide (SiO2) first insulating layer is formed over device areas, and a first silicon nitride (Si3N4) etch-stop layer is deposited, and openings are etched for capacitor node contacts. A first polysilicon layer is deposited to a thickness sufficient to fill the openings and to form an essentially planar surface. A second insulating layer is deposited and patterned to form portions with vertical sidewalls over the node contacts. A conformal second Si3N4 layer is deposited and etched back to form spacers on the vertical sidewalls, and the first polysilicon layer is etched to the first Si3N4 layer. The second insulating layer is selectively removed using HF acid while the first polysilicon and first Si3N4 layers prevent etching of the underlying first SiO2 layer.

Abstract: A method for fabricating a microelectronic layer. There is first provided a substrate. There is then formed over the substrate a target layer. There is then formed upon the target layer a patterned photoresist layer which defines a first aperture, where the first aperture has a first aperture width which exposes a first portion of the target layer. There is then reflowed thermally the patterned photoresist layer to form a reflowed patterned photoresist layer which defines a substantially straight sided second aperture. The second aperture has a second aperture width less than the first aperture width, and the second aperture thus exposes a second portion of the blanket target layer of areal dimension less than the first portion of the blanket target layer. Finally, there is then fabricated the target layer to form a fabricated target layer while employing the reflowed patterned photoresist layer as a mask layer.

Abstract: Within a method for fabricating a microelectronic device there is first provided a silicon substrate. There is then formed upon the silicon substrate a first series of structures having a comparatively narrow spacing which leaves exposed a first series of comparatively narrow portions of the silicon substrate, and where the first series of structures is separated from a second series of structures also formed upon the silicon substrate, the second series of structures having a comparatively wide spacing which leaves exposed a second series of comparatively wide portions of the silicon substrate. There is then masked one of the first series of comparatively narrow portions of the silicon substrate and the second series of comparatively wide portions of the silicon substrate.

Abstract: A method is disclosed for forming self-aligned, borderless contact and vias together and simultaneously with relaxed photolithographic alignment tolerances using a modified dual damascene process having two etch-stop layers. A first etch-stop layer is formed over a first dielectric layer. A second dielectric layer and a second etch-stop layer are next formed sequentially over the first etch-stop layer. Contact/via hole pattern is etched into the first etch-stop layer using a first photoresist layer. A second photoresist layer, patterned with metal line trench pattern, is formed over the contact/via patterned first etch-stop layer. The contact/via hole openings are etched into the first dielectric layer until the second etch-stop layer is reached. Then, both the first and second etch-stop layers are etched through the openings.

Abstract: This invention relates to a novel fuse structure and method for deleting redundant circuit elements on integrated circuits. This fuse structure is useful for increasing the repair yield on RAM chips by deleting defective rows of memory cells. The method involves forming a fuse area in a patterned electrically conducting layer also used to form interconnections. A relatively thin (0.4 um) insulating layer is deposited having a uniform thickness across the substrate. The next level of patterned interconnections is formed with a portion of the layer aligned over the fuse area to serve as an etch-stop layer. For example, the conducting layers can be the first and second poly-silicon layers on a RAM chip. The remaining multilevel of interconnections is then formed having a number of relatively thick interlevel dielectric (ILD) layers interposed which can have an accumulative large variation in thickness across the substrate.

Abstract: A process for fabricating a crown shaped, capacitor structure, in a SAC opening, featuring a silicon nitride spacer, located on the walls of a bottom portion of the SAC opening, has been developed. The process features forming a SAC opening in a thick silicon oxide layer, then repairing, or filling, seams or voids, that may be present in the thick silicon oxide layer, at the perimeter of the SAC opening, via formation of a silicon nitride spacer on the sides of the SAC opening. Subsequent processing features: the isotropic removal of a top portion of the silicon nitride spacer; the formation of a polysilicon storage node structure, in the SAC opening; and the recessing of a top portion of the thick silicon oxide layer, resulting in exposure of additional polysilicon storage node, surface area.

Abstract: A new method of forming an improved buried contact junction is described. A gate silicon oxide layer is provided over the surface of a semiconductor substrate. A polysilicon layer is deposited overlying the gate oxide layer. A hard mask layer is deposited overlying the polysilicon layer. The hard mask and polysilicon layers are etched away where they are not covered by a mask to form a polysilicon gate electrode and interconnection lines having a silicon nitride layer thereover wherein gaps are left between the gate electrode and interconnection lines. A layer of dielectric material is deposited over the substrate to fill the gaps. The had mask layer is removed. Thereafter, the polysilicon layer is etched away where it is not covered by a buried contact mask to form an opening to the semiconductor substrate. Ions are implanted into the semiconductor substrate within the opening to form the buried contact.

Abstract: A method for making a planar interlevel dielectric (ILD) layer, having improved thickness uniforming across the substrate surface, over a patterned electrically conducting layer is achieved. The method involves forming electrically conducting lines on which is deposited a conformal first insulating layer that is uniformly thick across the substrate. An etch-stop composed of Si3N4 is deposited and a second insulating layer, composed of SiO2 or a low-dielectric-constant insulator, is deposited. The second insulating layer is then partially chemically/mechanically polished back to within a few thousand Angstroms of the etch-stop layer. The remaining second insulating layer is then plasma etched back selectively to the etch-stop layer to form a planar surface having a uniformly thick first insulating layer over the electrically conducting lines. The contact openings or via holes can now etched to a uniform depth in the etch-stop layer and the first insulating layer across the substrate.

Abstract: A process for forming crown shaped capacitor structures, for a DRAM device, has been developed. The process features the use of a disposable insulator layer, applied prior to photolithographic and dry etching procedures, used to define the capacitor upper plate structures. The disposable insulator layer alleviates the topography effects presented by crown shaped storage node structures, relaxing the complexity of the patterning of the capacitor upper plate structures.

Abstract: A new method is provided to create a gradated dopant concentration in the contact plug of DRAM devices whereby a high dopant concentration is present at the bottom of the plug and a low dopant concentration is present at the top of the plug. Two layers of dielectric are deposited; the upper layer serves as a layer to adjust the dopant concentration in the lower layer. This adjustment is done by Rapid Thermal anneal of both layers of dielectric. After the dopant concentration has been adjusted, the upper layer of dielectric is removed and the upper section of the contact node is formed using lightly doped poly. The high dopant concentration at the bottom of the contact plug results in low contact resistance between the plug and the underlying silicon substrate. A low dopant concentration at the top surface of the contact plug results in low oxidation of the surface of the plug.

Abstract: A process for reducing the aspect ratio, for narrow diameter contact holes, formed in thick insulator layers, used to integrate logic and DRAM memory devices, on the same semiconductor chip, has been developed. The process of reducing the aspect ratio, of these contact holes, features initially forming, via patterning procedures, lower, narrow diameter contact holes, to active device regions, in the logic area, while also forming self-aligned contact openings to source/drain regions in the DRAM memory region. After forming tungsten structures, in the lower, narrow diameter contact holes, polycide bitline, and polysilicon capacitor structures, are formed in the DRAM memory region, via deposition, and patterning, of upper level insulator layers, and polysilicon and polycide conductive layers. Upper, narrow diameter openings, are then formed in the upper level insulator layers, exposing the top surface of tungsten structures, located in the lower, narrow diameter contact holes.

Abstract: A method for making crown capacitors using a new and improved crown etch window process for DRAM cells is described. After forming FETs for the memory cells, a planar first insulating layer (IPO-1) is formed and bit lines are formed thereon. A second insulating layer (IPO-2) is deposited, and a first etch-stop layer and a disposable insulating layer are deposited. Contact openings are etched in the layers to the substrate, and are filled with a polysilicon to form capacitor node contact plugs. The disposable layer is removed to expose the upper portions of the plugs extending above the first etch-stop layer. A second etch-stop layer is deposited and a thick insulating layer is deposited in which capacitor openings are etched over and to the plugs.

Abstract: A process for forming a DRAM, cylindrical shaped, stacked capacitor structure, located under a bit line structure, has been developed. The process features defining a polysilicon cell plate structure, during the same photolithotgraphic and anisotropic etching procedures, used to open a bit line contact hole. The bit line contact hole is formed by first opening a top portion of the bit line contact hole, using a photoresist shape as an etch mask, and after the formation of silicon nitride spacers, on the sides of the top portion of the bit line contact hole, the bottom portion of the bit line contact hole is opened, using silicon nitride as an etch mask.

Abstract: A new method of maintaining good control of the dielectric thickness over a top capacitor plate during planarization by CMP by introducing a CMP stop layer under the topmost dielectric layer is described. Semiconductor device structures, including a node contact region, are provided in and on a semiconductor substrate. A bottom plate electrode is formed contacting the node contact region through an opening in a first insulating layer. A capacitor dielectric layer is deposited overlying the bottom plate electrode. A second conducting layer is deposited overlying the capacitor dielectric to form a top plate electrode of the capacitor. A second insulating layer is deposited overlying the second conducting layer. A silicon nitride polish stop layer is deposited overlying the second insulating layer. The polish stop layer, second insulating layer, second conducting layer, and capacitor dielectric layer are patterned to form the DRAM integrated circuit device.

Abstract: A method using a two-step contact process for making word-line strapping on DRAM devices was achieved. The method replaces a single-step contact process in which it is difficult to etch the smaller contact openings. After partially completing the DRAM cells by forming gate electrodes and word lines having a first hard mask, a planar first insulating layer is formed. Capacitor node contact openings are etched and capacitors with a protective second hard mask are completed. A thin first photoresist mask with improved resolution is used to etch small first contact openings in the first insulating layer to the word lines, while the second hard mask protects the capacitors from etching. Tungsten plugs are formed in the openings, and an interlevel dielectric layer is deposited over the capacitors. A thin second photoresist mask with improved resolution is used to etch second contact openings to the tungsten plugs.

Abstract: A method for forming a self aligned contact wherein a dielectric layer is formed directly on a conductive structure according the present invention. A semiconductor structure having a polysilicon conductive structure (such as a bit line) thereon is provided. A contact area is located on the semiconductor structure adjacent to the conductive structure. A dielectric layer, preferably composed of silicon oxide is formed over the conductive structure and the semiconductor structure. A top hard mask layer is formed over the dielectric layer. A contact opening is formed in the top hard mask layer and the dielectric layer using an etch selective to oxide over polysilicon, thereby exposing the contact region of the semiconductor structure adjacent to the conductive structure without etching through the conductive structure.

Abstract: This invention relates to a novel fuse structure and method for deleting redundant circuit elements on integrated circuits. This fuse structure is useful for increasing the repair yield on RAM chips by deleting defective rows of memory cells. The method involves forming a fuse area in a patterned electrically conducting layer also used to form interconnections. A relatively thin (0.4 um) insulating layer is deposited having a uniform thickness across the substrate. The next level of patterned interconnections is formed with a portion of the layer aligned over the fuse area to serve as an etch-stop layer. For example, the conducting layers can be the first and second polysilicon layers on a RAM chip. The remaining multilevel of interconnections is then formed having a number of relatively thick interlevel dielectric (ILD) layers interposed which can have an accumulative large variation in thickness across the substrate.