Abstract:
For forming a highly conductive junction in an active device area of a semiconductor substrate, a first dopant is implanted into the active device area to form a preamorphization region. A second dopant is then implanted into the preamorphization region to have a dopant profile along a depth of the preamorphization region, and the dopant profile has a dopant peak within the preamorphization region. A RTA (Rapid Thermal Anneal) is performed to recrystallize a portion of the preamorphization region from an interface between the preamorphization region and the semiconductor substrate to below the dopant peak. A LTP (Laser Thermal Process) is then performed to recrystallize a remaining portion of the preamorphization region that has not been recrystallized during the RTA (Rapid Thermal Anneal) to activate a substantial portion of the second dopant in the preamorphization region. In this manner, a relatively small portion of junction at the interface of the junction with the semiconductor substrate is recrystallized using a RTA (Rapid Thermal Anneal) process before the LTP (Laser Thermal Process). The interface of the junction with the semiconductor substrate that is recrystallized using a RTA (Rapid Thermal Anneal) has a minimized amount of crystallization defects such that the resistance of the junction is minimized. Such a highly conductive junction may be formed as a drain extension, a source extension, a drain contact junction, and a source contact junction of a field effect transistor for minimizing the series resistance at the drain and source of the field effect transistor and thus for enhancing the speed performance of the field effect transistor.
Abstract:
A method of manufacturing an integrated circuit is disclosed herein. The method includes providing an implant in a semiconductor to create an amorphous region; growing a thermal oxide layer on the amorphous region such that the thermal oxide layer consumes a portion of the amorphous region; and removing the thermal oxide layer such that the resulting amorphous region is super-shallow.
Abstract:
A method of fabricating an integrated circuit with a gate structure comprised of an oxide/polysilicon/metal stack. The method includes forming the gate structure by using a metal plug as a hard mask in place of a hard mask produced using photolithography. Thus, linewidth limitations of conventional photolithography do not apply. Specifically, the method includes providing a pattern over a semiconductor substrate; partially filling the pattern with a polysilicon material such that a trench is left in the polysilicon material, and filling the trench in the polysilicon material with metal to form a plug. After forming the materials, excess materials are removed leaving the gate structure.
Abstract:
A field effect transistor is fabricated to have a drain overlap and a source overlap to minimize series resistance between the gate and the drain and between the gate and the source of the field effect transistor. The parasitic Miller capacitance formed by the drain overlap and the source overlap is reduced by forming a depletion region at the sidewalls of the gate structure of the field effect transistor. The depletion region at the sidewalls of the gate structure is formed by counter-doping the sidewalls of the gate structure. The sidewalls of the gate structure at the drain side and the source side of the field effect transistor are doped with a type of dopant that is opposite to the type of dopant within the gate structure. Such dopant at the sidewalls of the gate structure forms a respective depletion region from the sidewall into approximately the edge of the drain overlap and source overlap that extends under the gate structure to reduce the parasitic Miller capacitance formed by the drain overlap and the source overlap.
Abstract:
In a method for fabricating a highly activated shallow abrupt doped junction in a semiconductor substrate, a first dopant is implanted into a predetermined surface of the semiconductor substrate to form a preamorphization junction having a first predetermined depth from the predetermined surface of the semiconductor substrate. Furthermore, a second dopant is implanted into the preamorphization junction with a dopant profile along a depth of the semiconductor substrate from the predetermined surface of the semiconductor substrate. A peak of the dopant profile is located at a fraction of the first predetermined depth of the preamorphization junction. A silicidation RTA (Rapid Thermal Anneal) is performed to form silicide on the semiconductor substrate. The silicidation RTA (Rapid Thermal Anneal) recrystallizes the preamorphization junction from the first predetermined depth of the preamorphization junction up to an unrecrystallized depth of the preamorphization junction. The unrecrystallized depth of the preamorphization junction does not reach up to the peak of the dopant profile. An additional RTA (Rapid Thermal Anneal) is performed to recrystallize the preamorphization junction from the unrecrystallized depth of the preamorphization junction substantially up to the predetermined surface of the semiconductor substrate. The highly activated shallow abrupt doped junction is formed by activation of a substantial portion of the second dopant in the preamorphization junction during the additional RTA (Rapid Thermal Anneal).
Abstract:
A semiconductor device with improved short channel characteristics is formed with a buried amorphous region comprising a retrograde impurity region having the impurity concentration peak of the semiconductor substrate. The buried amorphous region, formed below the channel region, suppresses diffusion of displaced atoms and holes from the source/drain regions and reduces the resistance against latch-up phenomenon, thereby improving short channel characteristics.
Abstract:
A shallow doped junction that is part of an integrated circuit device within a semiconductor substrate is formed with box-shaped implant profiles for implantation of the amorphizing implant species and the dopant implant species such that the doped junction has minimized sheet resistance. A box-shaped implant profile for implantation of the amorphizing implant species is formed from implantation of the amorphizing implant species with a plurality of projection ranges to form a plurality of implant profiles. A box-shaped implant profile for implantation of the dopant implant species is formed from implantation of the dopant implant species with a plurality of projection ranges to form a plurality of implant profiles. In addition, each of the plurality of implant profiles for the dopant implant species is preferably below the solid solubility of the dopant implant species within the semiconductor substrate. By controlling the implant profiles of the amorphizing implant species and the dopant implant species during fabrication of the doped junction, the sheet resistance of the doped junction is minimized. In addition, the temperature and the time period for activating the dopant implant species in a RTA (Rapid Thermal Anneal) process is also minimized such that the doped junction remains relatively shallow.
Abstract:
A field effect transistor (FET) is formed on a silicon substrate, with a nitride gate insulator layer being deposited on the substrate and an oxide gate insulator layer being deposited on the nitride layer to insulate a gate electrode from source and drain regions in the substrate. The gate material is then removed to establish a gate void, and spacers are deposited on the sides of the void such that only a portion of the oxide layer is covered by the spacers. Then, the unshielded portion of the oxide layer is removed, thus establishing a step between the oxide and nitride layers that overlays the source and drain extensions under the gate void to reduce subsequent capacitive coupling and charge carrier tunneling between the gate and the extensions. The spacers are removed and the gate void is refilled with gate electrode material.
Abstract:
A method of fabricating an integrated circuit with ultra-shallow source and drain junctions utilizes a damascene process. The substrate is over-etched to form extensions in the source and drain regions. The process can be utilized for P-channel or N-channel metal oxide field semiconductor effect transistors (MOSFETS).
Abstract:
An integrated circuit and method of fabrication is provided for an integrated circuit having punch-through suppression. Unlike conventional methods of punch-through suppression wherein a dopant implant is fabricated in the device, the present invention utilizes an inert ion implantation process whereby inert ions are implanted through a fabricated gate structure on the semiconductor substrate to form a region of inert ion implant between source and drain regions of a device on the integrated circuit. This accumulation region prevents punch-through between source and drain regions of the device. In a second embodiment, the inert ion implantation is used in conjunction with the conventional punch-through dopant implant. In this second embodiment, diffusion of the implant during subsequent thermal annealing is suppressed by the inert ion accumulation in the subsurface region of the device. Accordingly, improved integrated circuits and methods of fabricating an integrated circuit having punch-through suppression are disclosed.