Abstract: A process for creating a storage node electrode, for a DRAM cell, exhibiting increased surface area resulting from the formation of an agglomerated metal silicide layer, on the top surface of the storage node electrode, has been developed. The process features creating a polysilicon, storage node electrode shape, followed by the formation of an overlying, agglomerated titanium disilicide layer. The agglomerated titanium disilicide layer is formed from a RTA procedure, applied to a smooth titanium disilicide layer, located on the polysilicon, storage node electrode.

Abstract: A method and structure for forming a modified field oxide region having increased field oxide threshold voltages (Vth) and/or reduced leakage currents between adjacent device areas is achieved. The method involves forming a field oxide using the conventional local oxidation of silicon (LOCOS) using a patterned silicon nitride layer as a barrier to oxidation. After forming the LOCOS field oxide by thermal oxidation and removing the silicon nitride, a conformal insulating layer composed of silicon oxide is deposited and anisotropically etched back to form sidewall insulating portions over the bird's beak on the edge of the LOCOS field oxide, thereby forming a new modified field oxide. P-channel implants are formed in the device areas. Then a second implant is used to implant through the modified field oxide to provide channel-stop regions with modified profiles that increase the field oxide Vth and/or reduce leakage current between device areas.

Abstract: A new method is provided for treating the surface of a layer of passivation where this layer of passivation comprises silicon dioxide or silicon nitride. An oxygen rich layer is created over the surface of the layer of passivation. Under the first embodiment of the invention a layer of silicon oxide is deposited over the surface of a substrate, a layer of plasma enhanced silicon nitride is deposited over the surface of the layer of silicon oxide, and a layer of oxynitride is deposited over the surface of the layer of plasma enhanced silicon nitride. Under the second embodiment of the invention a layer of silicon oxide is deposited over the surface of a substrate, a layer of silicon nitride is deposited over the surface of layer of silicon oxide. The surface of the layer of silicon nitride is oxidized by N2O or O2 plasma treatment.

Abstract: A method of forming self aligned contacts in silicon integrated circuit wafers which has a reduced contact resistance is described. A contact hole formed in a layer of dielectric is filled with polysilicon using a split polysilicon process. A first polysilicon layer is deposited after the contact hole is opened. The first polysilicon is preferably, but not necessarily, high temperature film doped polysilicon. The first polysilicon is then treated using C2F6/O2. A second polysilicon layer, preferably furnace doped polysilicon, is then deposited to completely fill the contact hole. The wafer is then planarized, using chemical mechanical polishing or back etching, leaving polysilicon completely filling the contact hole and forming a low resistance contact.

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: An improved method to form self-aligned contacts with polysilicon plugs is described. A semiconductor substrate is provided. A silicon oxide layer overlying the semiconductor substrate is deposited. A contact hole is etched through the silicon oxide layer to the surface of the semiconductor substrate. A polysilicon layer is deposited overlying the silicon oxide layer and filling completely the contact hole. The polysilicon layer is polished away to define only polysilicon remaining in the contact hole and to remove the silicon oxide layer sufficient to flatten the top surface of the silicon oxide layer. The fabrication of the integrated circuit device is completed.

Abstract: This invention provides a method for forming a self aligned contact plug with low contact resistance in a semiconductor device using a two step process of (1) forming a high temperature polysilicon film and (2) forming a furnace doped polysilicon layer. The process begins by providing a substrate structure, having a first gate structure and a second gate structure thereon and having a contact area between the first gate structure and the second gate structure. An inter level dielectric layer is formed over the first gate structure and the second gate structure. The interlevel dielectric layer is patterned to form a self aligned contact opening over the contact area. Impurity ions are implanted into the substrate structure through the self aligned contact opening to form source and drain regions. In the key steps, a high temperature polysilicon film is formed over the source and drain regions, and a furnace doped polysilicon layer is formed over the high temperature polysilicon film.

Abstract: A process for creating a storage node electrode, for a DRAM cell, exhibiting increased surface area resulting from the formation of an agglomerated metal silicide layer, on the top surface of the storage node electrode, has been developed. The process features creating a polysilicon, storage node electrode shape, followed by the formation of an overlying, agglomerated titanium disilicide layer. The agglomerated titanium disilicide layer is formed from a RTA procedure, applied to a smooth titanium disilicide layer, located on the polysilicon, storage node electrode.

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.

Abstract: A method of fabricating a metal guard ring (e.g., 139 149 159) around for a metal fuse 141 and fuse opening 88. The metal fuse 41 is formed from a second metal layer (M2) (or M3 or M4, etc.) and is connected to an underlying polysilicon layer 22 by fuse interconnections 129A 129B. The method comprises:a) forming a first polysilicon line 22A and a second polysilicon line 22B over at least the fuse area 84 insulated (e.g.

Abstract: A method for forming protection layers completely around a metal fuse to protect the metal fuse 74A and metal lines 74B from moisture corrosion from fuse opening and micro-cracks in dielectric layers. The invention surrounds the fuse on all sides with two protection layers: a bottom protection layer 70 and a top protection layer 78. The top protection layer 78 is formed over the fuse metal, the sidewalls of the metal fuse and the bottom protection layer 70. The protection layers 70 78 of the invention form a moisture proof seal structure around the metal fuse 74A and protect the metal fuse 74A and metal lines 74B from moisture and contaminates.

Abstract: A process for creating an insulator filled, shallow trench, in a semiconductor substrate, in which the insulator layer in the shallow trench, is not exposed to procedures used to remove defining composite insulator layers, has been developed. The process features creating a lateral recess, in a thick silicon nitride layer, used as a component of a composite insulator layer, where the composite insulator layer is used for subsequent definition of the shallow trench, in the semiconductor substrate.

Abstract: A contact between a conductor and a substrate region in a MOSFET SRAM device is formed by a dielectric layer on the surface of a partially completed SRAM device with pass transistors and latch transistors with the dielectric layer being formed above those pass and latch transistors. A thin film transistor gate electrode and an interconnection line are formed on the upper surface of the dielectric layer. A gate oxide layer covers the gate electrode and the interconnection line. A polysilicon conductive layer which covers the gate oxide layer includes a channel region between a source region and a drain region which are formed on opposite sides of the channel region. There is a channel mask formed self-aligned with the channel region formed above the channel region as well as being above the gate electrode. The polysilicon conductive layer is doped aside from the channel mask thereby providing a source region and a drain region on opposite sides of the channel region.

Abstract: A method and structure for forming a modified field oxide region having increased field oxide threshold voltages (V.sub.th) and/or reduced leakage currents between adjacent device areas is achieved. The method involves forming a field oxide using the conventional local oxidation of silicon (LOCOS) using a patterned silicon nitride layer as a barrier to oxidation. After forming the LOCOS field oxide by thermal oxidation and removing the silicon nitride, a conformal insulating layer composed of silicon oxide is deposited and anisotropically etched back to form sidewall insulating portions over the bird's beak on the edge of the LOCOS field oxide, thereby forming a new modified field oxide. P-channel implants are formed in the device areas. Then a second implant is used to implant through the modified field oxide to provide channel-stop regions with modified profiles that increase the field oxide V.sub.th and/or reduce leakage current between device areas.

Abstract: A method for making cylinder-shaped stacked capacitors for DRAMs is described. A planar first insulating layer is formed over device areas. An etch-stop layer, a second insulating layer, and a polish-back endpoint detect layer are deposited in which cylinder-shaped capacitors with node contacts are formed. First openings for node contacts are etched in the polish-back and second insulating layers to the etch-stop layer aligned over the device areas. Wider second openings, aligned over the first openings, are etched through the polish-back layer, and also removes the etch-stop layer in the first openings. The second insulating layer in the second openings is etched to the etch-stop layer, while the first insulating layer is etched in the first openings for node contact openings. A doped first polysilicon layer is deposited and polished back to the polish-back detect layer to form concurrently the node contacts in the first openings and bottom electrodes in the second openings.

Abstract: A method of forming a contact between a conductor and a substrate region in a MOSFET SRAM starts with forming a dielectric layer on the surface of a partially completed SRAM device with pass and latch transistors covering the transistors. Then, form a thin film gate electrode and an interconnect on the dielectric layer with a gate oxide layer covering the gate electrode and the interconnect; cover the gate oxide layer with a poly conductive layer. Then form a silicon oxide layer over the poly conductive layer and pattern the silicon oxide layer to form a silicon oxide channel mask over the poly conductive layer which is used to pattern the silicon oxide layer into a channel mask over the gate electrode. The channel mask is used for patterning the implanting of dopant into the poly conductive layer aside from the channel mask to form a source region, a drain region and an interconnect in the poly conductive layer.

Abstract: A method for making improved capacitor bottom electrodes (capacitor nodes) having longer refresh cycle times and increased capacitance for DRAM cells has been achieved. The method involves using a polysilicon high-temperature film (HTF) instead of the conventional doped polysilicon to form the node capacitors. After forming the DRAM pass transistors (FETs) and depositing an insulating layer, node contact openings are etched in the insulator to the drain of the FET. The capacitor bottom electrodes are formed by depositing a polysilicon HTF at a temperature of at least 650.degree. C. using a reactant gas mixture of H.sub.2 /SiH.sub.4 /PH.sub.3, which results in a longer refresh cycle time and increased capacitance. This results in a significantly improved final die yield. After forming an interelectrode dielectric layer on the bottom electrodes, another doped polysilicon layer is deposited to form the top electrodes to complete the DRAM cells.

Abstract: A method for preventing bubble formation over source/drain active areas in p-channel MOSFETs is described. Bubble formation occurs when the source/drain areas and silicon containing gate electrodes are implanted with BF.sub.2.sup.+ molecule ions following an anisotropic LDD spacer etch using a plasma. It is found that the plasma causes the silicon surface to become prone to adsorption of BF.sub.2.sup.+ molecule ions during the source/drain/gate implantation. These adsorbed species are released and form bubbles during reflow of a subsequently deposited glass layer. The invention performs the spacer etch only partially with the anisotropic plasma and completes the spacer formation with a wet etch. The active silicon and gate electrode surfaces are thus not damaged by the plasma. Consequently adsorption of BF.sub.2.sup.+ molecule ions is inhibited and bubble formation does not occur during reflow.

Abstract: A process is provided in which silicon thin film transistors fabricated with polycrystalline silicon, silicon oxide, and silicon conductive layers are exposed to microwave plasmas containing water vapor and to subsequent annealing steps to bring about an improvement in the ratio of device drain current in the conductive state to that in the non-conductive state, and a lower device subthreshold voltage swing.