摘要:
A method of forming bitlines for a memory cell array of an integrated circuit and conductive lines interconnecting transistors of an external region outside of the memory cell array is provided. The method includes patterning troughs in a dielectric region covering the memory cell array according to a first critical dimension mask. Bitline contacts to a substrate and bitlines are formed in the troughs. Thereafter, conductive lines are formed which consist essentially of at least one material selected from the group consisting of metals and conductive compounds of metals in horizontally oriented patterns patterned by a second critical dimension mask, wherein the conductive lines interconnect the bitlines to transistors of external circuitry outside of the memory cell array, the conductive lines being interconnected to the bitlines only at peripheral edges of the memory cell array.
摘要:
A method of forming borderless contacts and a borderless contact structure for semiconductor devices. A preferred embodiment comprises using a second etch selectivity material disposed over a first etch selectivity material to preserve the first etch selectivity material during the etch processes for the various material layers of the semiconductor device while forming the borderless contacts.
摘要:
A method of forming borderless contacts and a borderless contact structure for semiconductor devices. A preferred embodiment comprises using a second etch selectivity material disposed over a first etch selectivity material to preserve the first etch selectivity material during the etch processes for the various material layers of the semiconductor device while forming the borderless contacts.
摘要:
An improved pitcher-shaped active area for a field effect transistor that, for a given gate length, achieves an increase in transistor on-current, a decrease in transistor serial resistance, and a decrease in contact resistance. The pitcher-shaped active area structure includes at least two shallow trench insulator (STI) structures formed into a substrate that defines an active area structure, which includes a widened top portion with a larger width than a bottom portion. An improved fabrication method for forming the improved pitcher-shaped active area is also described that implements a step to form STI structure divots followed by a step to migrate substrate material into at least portions of the divots, thereby forming a widened top portion of the active area structure. The fabrication method of present invention forms the pitcher-shaped active area without the use of lithography, and therefore, is not limited by the smallest ground rules of lithography tooling.
摘要:
An improved pitcher-shaped active area for a field effect transistor that, for a given gate length, achieves an increase in transistor on-current, a decrease in transistor serial resistance, and a decrease in contact resistance. The pitcher-shaped active area structure includes at least two shallow trench insulator (STI) structures formed into a substrate that defines an active area structure, which includes a widened top portion with a larger width than a bottom portion. An improved fabrication method for forming the improved pitcher-shaped active area is also described that implements a step to form STI structure divots followed by a step to migrate substrate material into at least portions of the divots, thereby forming a widened top portion of the active area structure. The fabrication method of present invention forms the pitcher-shaped active area without the use of lithography, and therefore, is not limited by the smallest ground rules of lithography tooling.
摘要:
An etch rate of a nitride liner layer is improved relative to an etch rate of a nitride cap layer. The nitride liner layer is located at an exposed portion of a substrate adjacent to a stacked structure also located atop the substrate. The nitride cap layer is located atop the stacked structure. An oxide spacer is formed along sidewalls of the stacked structure. The nitride liner layer is patterned and etched to form at least one opening therein to the substrate while the nitride cap layer remains substantially intact.
摘要:
A semiconductor device is fabricated to have improved bitline contact formation. Polysilicon is deposited between gate contacts that connect to transistors of DRAM memory cells. The polysilicon covers the gate contacts and continues to cover the gate contacts during subsequent processing steps. A bitline of, e.g., tungsten, is deposited so that it contacts at least a portion of the polysilicon, thereby providing electrical contact with the DRAM transistors.
摘要:
In a method of forming a contact, a liner reactive ion etch is affected on a substrate to remove silicon nitride and silicon oxide. An oxygen plasma ex-situ clean, a Huang AB clean, and a dilute hydrofluric acid (DHF) clean are affected. Amorphous silicon is deposited and an anneal is performed to regrow and recrystallize amorphous silicon.
摘要:
A semiconductor structure of reduced contact resistance is provided by providing a layer of amorphous silicon-derived material on an epitaxial silicon substrate having an average dopant concentration of at least about 1020 atoms/cm3 in the contact material within about 500 Å of the substrate.
摘要:
Methods for forming or etching silicon trench isolation (STI) in a silicon-on-insulator (SOI) region and a bulk silicon region, and a semiconductor device so formed, are disclosed. The STI can be etched simultaneously in the SOI and bulk silicon regions by etching to an uppermost silicon layer using an STI mask, conducting a timed etch that etches to a desired depth in the bulk silicon region and stops on a buried insulator of the SOI region, and etching through the buried insulator of the SOI region. The buried insulator etch for this process can be done with little complexity as part of a hardmask removal step. Further, by choosing the same depth for both the bulk and SOI regions, problems with a subsequent CMP process are avoided. The invention also cleans up the boundary between the SOI and bulk regions where silicon nitride residuals may exist.