Abstract: A transistor and a transistor fabrication method in which the heavy source/drain implants which require high-temperature thermal anneals are performed before the LDD implants which require lower temperature thermal anneals. In addition, the n-type arsenic source/drain implant which requires the highest temperature anneal is performed prior to the p-type boron implant which requires a lower temperature thermal anneal. In a conventional LDD, the LDD implants are performed first, prior to the source/drain implants. The LDD implants, especially the p-type boron implants, are annealed at a relatively low temperature. The source/drain implants require a higher thermal anneal temperature since they need to diffuse a longer distance. The n-type arsenic source/drain implants require an especially high temperature since arsenic is relatively large ion with a low diffusivity. During the high temperature thermal anneal, the LDD implants that are already present will migrate significantly.

Abstract: An integrated circuit fabrication method incorporating nitrogen into the polysilicon-dielectric interface in an MOS transistor. A semiconductor substrate having a P-well region and an N-well region is provided. Each well region includes channel regions and source/drain regions. A dielectric layer, preferably a thermal oxide, is formed on an upper surface of the semiconductor substrate. The thermal oxide can be grown in a nitrogen bearing ambient, an O.sub.2 ambient, or an H.sub.2 O ambient. Alternatively, the dielectric may be formed from a deposited oxide. Thereafter, a layer of polysilicon is formed on the dielectric layer and a plurality of "nitrogenated" polysilicon gates is formed on the dielectric layer over the channel regions. In a presently preferred embodiment, nitrogen species are introduced into the polysilicon gates with an ion implantation step. The nitrogen implantation step may alternatively be performed before or after the patterning of the polysilicon layer.

Abstract: A semiconductor process in which a silicon film is chemically vapor deposited upon a native oxide film as part of the gate oxide formation process. The invention contemplates a method of forming a thin gate dielectric semiconductor transistor. A semiconductor substrate which includes a native oxide film on an upper region of a silicon bulk is provided and a silicon film is deposited on the native oxide film. A first oxide film is then formed on a the native oxide film by thermally oxidizing a portion of the silicon film proximal to the native oxide film such that the thin gate dielectric comprises the native oxide film and the first oxide film. Thereafter, a conductive gate is formed on the thin gate dielectric and a pair of source/drain structures are formed within a pair of source/drain regions of the semiconductor substrate. The pair of source/drain structures are laterally displaced on either side of the channel region of the semiconductor substrate.

Abstract: A process is provided for producing active and passive devices on various levels of a semiconductor topography. As such, the present process can achieve device formation in three dimensions to enhance the overall density at which an integrated circuit is formed. The multi-level fabrication process not only adds to the overall circuit density, but does so with emphasis placed on high performance interconnection between devices on separate levels. The interconnect configuration is made as short as possible between features within one transistor level to features within another transistor level. This interconnect scheme lowers resistivity by forming a gate conductor of an upper level transistor upon a gate conductor of lower level transistor. Alternatively, the gate conductors can be a single conductive entity. In order to abut the gate conductors together, or form a single gate conductor, the upper level transistor is inverted relative to the lower level transistor.

Abstract: A communication system is provided that includes a mechanism for recognizing various communication protocols. That is, the communication system employs a packet processor which can adapt to sent and receive numerous protocols. The packet processor forms a part of a network adapter card or router associated with a LAN or a WAN. The packet processor includes subsystems which can be selectively re-configured so that the processor can dispatch and recognize differing protocols. More specifically, the reconfigurable processor can dispatch and recognize differing packet and field formats associated with various communication protocols. Re-configuration is performed on select subsystems using at least a portion of a field programmable logic cell if not portions of numerous logic cells confirmed within defined areas on which the integrated processor is fabricated. As such, the logic cells can be programmed at the user site and, after program, function at a high performance level.

Abstract: An integrated circuit is formed whereby junction of NMOS transistors are formed dissimilar to junctions of PMOS transistors. The NMOS transistors include an LDD area, an MDD area and a heavy concentration source/drain area. Conversely, the PMOS transistor include an LDD area and a source/drain area. The NMOS transistor junction is formed dissimilar from the PMOS transistor junction to take into account the less mobile nature of the junction dopants relative to the PMOS dopants. Thus, a lessening of the LDD area and the inclusion of an MDD area provide lower source/drain resistance and higher ohmic connectivity in the NMOS device. The PMOS junction includes a relatively large LDD area so as to draw the highly mobile, heavy concentration boron atoms away from the PMOS channel.

Abstract: A method is provided for forming a transistor in which capacitive coupling between the gate conductors and adjacent structures employed by the integrated circuit is reduced. According to an embodiment, a gate conductor is dielectrically spaced above a semiconductor substrate, and a masking structure is arranged upon an upper surface of the gate conductor. A source/drain implant self-aligned to opposed lateral sidewalls of the masking structure is performed to form source/drain implant areas within the substrate. Select portions of the gate conductor are removed such that opposed ends of the masking structure extend beyond opposed sidewall surfaces of the gate conductor. A lightly doped drain implant self-aligned to the opposed sidewall surfaces of the narrowed gate conductor is performed to form lightly doped drain implant areas within the substrate.

Abstract: An integrated circuit is formed whereby junctions of NMOS transistors are formed dissimilar to junctions of PMOS transistors. The NMOS transistors include an LDD area, at least one MDD area, and a heavy concentration source/drain area. Conversely, the PMOS transistor includes an LDD area and a source/drain area. The NMOS transistor junction is formed dissimilar from the PMOS transistor junction to take into account, inter alia, the less mobile nature of the junction dopants relative to the PMOS dopants. Thus, a lessening of the LDD area and the inclusion of an MDD area provides lower source-drain resistance and higher ohmic connectivity in the NMOS device. The PMOS junction includes a relatively large LDD area so as to draw the highly mobile, heavy concentration boron atoms away from the PMOS channel.

Abstract: An improved series and/or parallel connection of transistors within a logic gate is presented. The improved connection is brought about by a sacrificial structure on which gate conductors are formed adjacent sidewall surfaces of the sacrificial structure. The sacrificial structure thereby provides spacing between the series-connected or parallel-connected transistors. Upon removal of each sacrificial structure, a pair of transistors can be formed by implanting dopant species into the substrate on opposite sides of the spaced conductors. Beneath what was once a sacrificial structure is a shared implant area to which two transistors are coupled either in series or in parallel. By depositing the gate conductor material and then anisotropically removing the material except adjacent the vertical sidewall surfaces, an ultra short gate conductor can be formed concurrent with other gate conductors within a logic gate.

Abstract: A microcontroller integrates an internal memory accessible by the cores included thereon. Logic within the microcontroller compares memory addresses generated by the cores to values in a configuration register specifying a memory address range in which the internal memory resides. The logic generates a chip select signal to the internal memory if the memory address generated resides within the specified address range to enable accesses by the cores to the internal memory. The integrated circuit may be configured in a debug mode wherein the chip select signal is inhibited to the internal memory, however the chip select signal is provided external to the integrated circuit on a pin. The chip select signal may then be used to select an external memory which serves to overlay the internal memory address range. Thus the debug mode allows instruction code and data to reside in the external memory rather than the internal memory while in the debug mode.

Abstract: Low-mass implants, for example hydrogen and helium ions, are used in place of more typical dopants like boron, phosphorus, and arsenic for testing the performance of ion implanters. Consistency between ion implantation test runs with the low-mass ions may be used to provide information about the proper operation of ion implanters. Lower-mass ions do not transfer as much of their energy to the wafer as heavier ions. Consequently, high energy ion implantations with low-mass ions do not repair wafer surface damage to the same degree as ion implantations with high-mass ions. When sufficient surface damage exists, a thermawave tool can detect the damage and provide information about the performance of the ion implanter. This determination can be made in a one-step method. An additional advantage to implanting the test wafers with low-mass ions is being able to reuse the wafers for subsequent test runs.

Abstract: A method is provided for forming nitride sidewall spacers self-aligned between opposed sidewall surfaces of a gate conductor and a sacrificial dielectric sidewall. In one embodiment, a transistor is formed by first CVD depositing a sacrificial across a semiconductor substrate. An opening is etched through the dielectric to the underlying substrate. A gate oxide is thermally grown across the region of the substrate exposed by the first opening. A polysilicon gate conductor is then formed within the opening upon the gate oxide. Portions of the gate conductor and the gate oxide are removed to expose selective regions of the substrate. In this manner, a pair of opposed sidewall surfaces are defined for the polysilicon gate conductor which are laterally spaced from respective first and second dielectrics. A LDD implant is forwarded into those exposed selective regions of the semiconductor substrate.

Abstract: A system and method for detecting faults in wafer fabrication process tools by acquiring real-time process parameter signal data samples used to model the process performed by the process tool. The system includes a computer system including a DAQ device, which acquires the data samples, and a fault detector program which employs a process model program to analyze the data samples for the purpose of detecting faults. The model uses data samples in a reference database acquired from previous known good runs of the process tool. The fault detector notifies a process tool operator of any faults which occur thus potentially avoiding wafer scrap and potentially improving mean time between failures. The fault detector also receives notification of the occurrence of process events from the process tool, such as the start or end of processing a wafer, which the fault detector uses to start and stop the data acquisition, respectively.

Abstract: A semiconductor and/or integrated circuit is provided having reduced particulate count upon or within the circuit. During power ramp down post etch or deposition, particles which formed within the plasma used to effectuate etch or deposition are gradually swept from the region above the integrated circuit. Plasma, and more specifically, the field which forms the plasma is maintained but at reduced levels to allow gradual reduction of particles through a multitude of steps. The steps culminate in eliminating power to the electrodes and plasma between the electrodes. However, at the time at which power is absent, only a few of the original particles remain in the critical region above the integrated circuit. Residual particles can be removed in a purge step following the successive sequence of ramp down steps. Gap between the electrodes is increased to a final position early in the ramp down sequence so that additional electrode movement does not occur when the field is weakened.

Abstract: A interconnect structure is provided having a conductor with enhanced thickness. The conductor includes an upper portion and a lower portion, wherein the lower portion geometry is sufficient to increase the current-carrying capacity beyond that provided by the upper portion. The lower portion is formed by filling a trench within an upper dielectric region, and the upper portion is formed by selectively removing a conductive material from the upper dielectric surface except for regions directly above the lower portion. The upper and lower portions thereby form a conductor of enhanced cross-section which can be produced by modifying a via-etch mask, rather than having to reconfigure and/or move interconnect features formed by a metal mask.

Abstract: A method for isolating a first active region from a second active region, both of which are configured within a semiconductor substrate. The method comprises forming a dielectric masking layer above a semiconductor substrate. An opening is then formed through the masking layer. A pair of dielectric spacers are formed upon the sidewalls of the masking layer within the opening. A trench is then etched in the semiconductor substrate between the dielectric spacers. A first dielectric layer is then thermally grown on the walls and base of the trench. A CVD oxide is deposited into the trench and processed such that the upper surface of the CVD oxide is commensurate with the substrate surface. Portions of the spacers are also removed such that the thickness of the spacers is between about 0 to 200 .ANG.. The semiconductor topography is then exposed to a barrier-entrained gas and heated so that barrier atoms become incorporated in regions of the active areas in close proximity to the trench isolation structure.

Abstract: A process is provided for forming a transistor gate conductor having an etch stop arranged at a depth below its upper surface such that the lateral width of the gate conductor above the etch stop may be exclusively narrowed to provide for reduction of transistor channel length. A masking layer, i.e., photoresist, patterned above the gate conductor is isotropically etched so as to minimize its lateral width prior to etching the gate conductor. Portions of the gate conductor not protected by the photoresist may be etched from above the etch stop to define a new pair of opposed sidewall surfaces for the upper portion of the gate conductor. The lateral width of the upper portion of the gate conductor thus may be reduced to a smaller dimension than that of conventional gate conductors. The gate conductor is subjected to an anisotropic etch in which portions of the gate conductor not protected by the narrowed photoresist are etched down to the etch stop.

Abstract: An improved multilevel interconnect structure is provided. The interconnect structure includes several levels of conductors, wherein conductors on one level are staggered with respect to conductors on another level. Accordingly, a space between conductors on one level is directly above or directly below a conductor within another level. The staggered interconnect lines are advantageously used in densely spaced regions to reduce the interlevel and intralevel capacitance. Furthermore, an interlevel and an intralevel dielectric structure includes optimally placed low K dielectrics which exist in critical spaced areas to minimize capacitive coupling and propagation delay problems. The low K dielectric, according to one embodiment, includes a capping dielectric which is used to prevent corrosion on adjacent metallic conductors, and serves as an etch stop when conductors are patterned.

Abstract: A multilevel interconnect structure is provided. The multilevel interconnect structure includes two, three or more levels of conductors formed according to at least two exemplary embodiments. According to one embodiment, the contact structure which links conductors on one level to an underlying level is formed by a single via etch step followed by a fill step separate from a fill step used in filling the via. In this embodiment, the via is filled with a conductive material which forms a plug separate from the material used in forming the interconnect. In another exemplary embodiment, the step used in filling the via can be the same as that used in forming the interconnect. In either instance, a via is formed through a first dielectric to underlying conductors. A second dielectric is patterned upon the first dielectric and serves to laterally bound the fill material used in producing the overlying interconnect.

Abstract: A semiconductor process in which a dielectric layer is formed on an upper surface of a semiconductor substrate which includes a silicon base layer. Thereafter, an upper silicon layer is formed on an upper surface of the dielectric layer. The dielectric layer and the upper silicon layer are then patterned to form first and second silicon-dielectric stacks on the upper surface of the base silicon layer. The first and second silicon-dielectric stacks are laterally displaced on either side of a channel region of the silicon substrate and each include a proximal sidewall and a distal sidewall. The proximal sidewalls are approximately coincident with respective boundaries of the channel region. Thereafter, proximal and distal spacer structures are formed on the proximal and distal sidewalls respectively of the first and second silicon-dielectric stacks. A gate dielectric layer is then formed on exposed portions of the silicon base layer over a channel region of the base silicon layer.