摘要:
A method of forming low resistance contact structures in vias arranged between interconnect levels is provided. The method involves interconnect lines having an anti-reflective layer formed thereupon. An interlevel dielectric layer is formed over the interconnect lines. A photoresist layer is formed over the interlevel dielectric layer and patterned to define via locations. During via etch, an organic (carbon-based) polymer layer forms upon the anti-reflective-coated interconnect lines at the bottoms of the vias. The photoresist and the etch byproduct polymer layers are then removed using a dry etch process which employs a forming gas comprising nitrogen and hydrogen. A native oxide layer subsequently forms upon the anti-reflective-coated interconnect lines when exposed to oxygen. The native oxide layer is then removed, along with any residual etch byproduct polymer, during a sputter etch procedure. Each resulting via is substantially void of polymer and oxide residue so as to present a clean via area which allows ready adherence of a plug material to the anti-reflective coating.
摘要:
A method of forming an improved isolation trench between active regions within the semiconductor substrate. The improved method incorporates a trench liner having a nitrogen content of approximately 0.5 to 2.0 percent. A pad layer is formed on a silicon substrate and a nitride layer is formed on the pad layer. Thereafter, a photoresist layer is patterned on the silicon nitride layer such that regions of the nitride layer are exposed where an isolation trench will subsequently be formed. Next, the exposed regions of the nitride layer and the pad layer situated below the exposed regions of the nitride layer are etched away to expose regions of the silicon substrate. Subsequently, isolation trenches are etched into the silicon substrate with a dry etch process. A trench liner is then formed and nitrogen incorporated into the trench liner. Incorporation of nitrogen into the trench liner can be accomplished by either forming the trench liner in the presence of a nitrogen bearing ambient or by forming a pure SiO.sub.2 trench liner and subsequently implanting the SiO.sub.2 trench liner with nitrogen. After formation of the nitrogenated trench liner, the trench is filled with a dielectric preferably comprised of a CVD oxide. Thereafter, the CVD fill dielectric is planarized and the nitride layer is stripped away.
摘要:
An isolation technique is provided for improving the overall planarity of filled isolation regions relative to adjacent silicon mesas. The isolation process results in a silicon mesa having enhanced mechanical and electrical properties. Planarity is performed by repeating the steps of filling isolation trenches, patterning large area isolation trenches, and refilling isolation trenches to present an upper surface having indents which can be readily removed by a chemical-mechanical polish. The silicon mesa upper surface is enhanced by utilizing a unique set of layers stacked upon the silicon substrate, and thereafter patterning the substrate to form raised silicon surfaces, or mesas, having the stacked layers thereon. The patterned, stacked layers include a unique combination of dissimilar compositions which, when removed, leave a silicon mesa upper surface which is recessed below the adjacent, filled trenches. The patterned stacked layers incorporate a polysilicon and/or oxide buffer which prevents deleterious migration of nitrogen from the overlying nitride layer to the underlying silicon mesa upper surface.
摘要:
A method of forming a self-aligned field oxide isolation structure without using silicon nitride. The method comprises forming a dielectric on an upper surface of a semiconductor substrate. The upper surface of the semiconductor substrate comprises an active region and an isolation region laterally adjacent to each other. A photoresist layer is patterned on top of the implant dielectric to expose regions of the implant dielectric over the active region. Nitrogen is then implanted into the active region through the implant dielectric. Nitrogen is preferably introduced into semiconductor substrate in an approximate atomic concentration of 0.5 to 2.0 percent. After the nitrogen has been implanted into a semiconductor substrate, the photoresist layer is stripped and the implant dielectric is removed. The wafer is then thermally oxidized such that a field oxide having a first thickness is grown over the isolation region and a thin oxide having a second thickness is grown over the active region. The presence of the nitrogen within the semiconductor substrate retards the oxidation rate of the silicon in the active region such that the thickness of the thin oxide is substantially less than the thickness of the thermal oxide. In a presently preferred embodiment, the field oxide has a thickness of 2,000 to 8,000 angstroms while the thin oxide has a thickness of less than 300 angstroms.
摘要:
A method of forming a self-aligned field oxide isolation structure without using silicon nitride. The method comprises forming a dielectric on an upper surface of a semiconductor substrate. The upper surface of the semiconductor substrate comprises an active region and an isolation region laterally adjacent to each other. A photoresist layer is patterned on top of the implant dielectric to expose regions of the implant dielectric over the active region. Nitrogen is then implanted into the active region through the implant dielectric. Nitrogen is preferably introduced into semiconductor substrate in an approximate atomic concentration of 0.5 to 2.0 percent. After the nitrogen has been implanted into a semiconductor substrate, the photoresist layer is stripped and the implant dielectric is removed. The wafer is then thermally oxidized such that a field oxide having a first thickness is grown over the isolation region and a thin oxide having a second thickness is grown over the active region. The presence of the nitrogen within the semiconductor substrate retards the oxidation rate of the silicon in the active region such that the thickness of the thin oxide is substantially less than the thickness of the thermal oxide. In a presently preferred embodiment, the field oxide has a thickness of 2,000 to 8,000 angstroms while the thin oxide has a thickness of less than 300 angstroms.
摘要:
An isolation technique is provided for improving the overall planarity of filled isolation regions relative to adjacent silicon mesas. The isolation process results in a silicon mesa having enhanced mechanical and electrical properties. Planarity is performed by repeating the steps of filling isolation trenches, patterning large area isolation trenches, and refilling isolation trenches to present an upper surface having indents which can be readily removed by a chemical-mechanical polish. The silicon mesa upper surface is enhanced by utilizing a unique set of layers stacked upon the silicon substrate, and thereafter patterning the substrate to form raised silicon surfaces, or mesas, having the stacked layers thereon. The patterned, stacked layers include a unique combination of dissimilar compositions which, when removed, leave a silicon mesa upper surface which is recessed below the adjacent, filled trenches. The patterned stacked layers incorporate a polysilicon and/or oxide buffer which prevents deleterious migration of nitrogen from the overlying nitride layer to the underlying silicon mesa upper surface.
摘要:
An improved process is provided for forming field dielectric in lieu of local oxidation process often referred to as the "LOCOS" process. The improved process utilizes blanket formation of first and second dielectrics across an entire semiconductor substrate. In a subsequent step, both first and second dielectrics are selectively removed in areas overlying active regions. The first and second dielectrics are formed using a combination of thermal growth and/or chemical deposition. The resulting field dielectric structure is relatively thin, yet demonstrates superior dielectric properties. Blanket formation followed by select removal ensures a fine-line demarcation between field and active regions and substantially eliminates encroachment problems normally associated with conventional LOCOS. Additionally, the thin field dielectric structure can be formed with rounded or reflowed corners to avoid step coverage problems for subsequently placed conductive elements.
摘要:
A method of fabricating a dual damascene structure is described. A dielectric layer and a metal hard mask layer are sequentially formed on a substrate having thereon a conductive layer and a liner layer. The metal hard mask layer and the dielectric layer are patterned to form a via hole exposing a portion of the liner layer. A gap-filling layer is filled in the via hole, having a height of ¼ to ½ of the depth of the via hole. A trench is formed in the metal hard mask layer and the dielectric layer. The gap-filling layer is removed to expose the portion of the liner layer, which is then removed. A metal layer is formed filling in the via hole and the trench, and then the metal hard mask layer is removed.
摘要:
A plurality of active areas are defined on a semiconductor substrate. Then at least one gate is formed on the semiconductor substrate to cover a portion of the active area. Thereafter a plurality of source/drain are formed in the active area not covered by the gate followed by forming a first dielectric layer on the semiconductor substrate to cover the gate and the source/drain. After that, at least one pixel cap top plate is formed atop the first dielectric layer and a capacitor dielectric layer is formed atop the surface of the top plate. Finally, at least one pixel cap bottom plate is formed atop the first dielectric layer to cover the top plate.
摘要:
A plurality of active areas are defined on a semiconductor substrate. Then at least one gate is formed on the semiconductor substrate to cover a portion of the active area. Thereafter a plurality of source/drain are formed in the active area not covered by the gate followed by forming a first dielectric layer on the semiconductor substrate to cover the gate and the source/drain. After that, at least one pixel cap top plate is formed atop the first dielectric layer and a capacitor dielectric layer is formed atop the surface of the top plate. Finally, at least one pixel cap bottom plate is formed atop the first dielectric layer to cover the top plate.