Abstract:
A method of fabricating an integrated circuit with ultra-shallow source/drain junctions utilizes a solid-phase impurity source. The solid-phase impurity source can be a doped silicon dioxide layer approximately 300 nm thick. The structure is thermally annealed to drive dopants from the solid-phase impurity source into the source and drain regions. The dopants from the impurity source provide ultra-shallow source and drain extensions. The process can be utilized for P-channel or N-channel metal oxide field semiconductor effect transistors (MOSFETS).
Abstract:
For fabricating a field effect transistor on an active device area of a semiconductor substrate, a gate dielectric and a gate electrode are formed on a portion of the active device area. First spacers are formed on sidewalls of the gate electrode and the gate dielectric. A contact dopant is implanted into exposed regions of the active device area to form drain and source contact junctions. A contact laser thermal anneal is performed to activate the contact dopant within the drain and source contact junctions. The first spacers are removed, and an extension dopant is implanted into exposed regions of the active device area to form drain and source extension junctions. An extension laser thermal anneal is performed to activate the extension dopant within the drain and source extension junctions. The fluence of the extension laser thermal anneal is lower than the fluence of the contact laser thermal anneal.
Abstract:
A method for making a ULSI MOSFET includes depositing a high-k gate insulator on a silicon substrate and then depositing a field oxide layer over the gate insulator. The field oxide layer is masked with photoresist and the photoresist patterned to establish first gate windows, and the oxide below the windows is then etched away to establish first gate voids in the oxide. The first gate voids are filled with a first metallic gate electrode material that is suitable for establishing a gate electrode of, e.g., an N-channel MOSFET. Second gate voids are similarly made in the oxide and filled with a second gate electrode material that is suitable for establishing a gate electrode of, e.g., an P-channel MOSFET or another N-channel MOSFET having a different threshold voltage than the first MOSFET. With this structure, plural threshold design voltages are supported in a single ULSI chip that uses high-k gate insulator technology.
Abstract:
A method of fabricating an integrated circuit utilizes asymmetric source/drain junctions. The process can be utilized for P-channel or N-channel metal oxide field semiconductor effect transistors (MOSFETS). The drain extension is deeper than the source extension. The source extension is more conductive than the drain extension. The transistor has reduced short channel effects and strong drive current and yet is reliable.
Abstract:
An integrated circuit includes a transistor with a T-shaped gate conductor. The T-shaped gate conductor can achieve a lower sheet resistance characteristic. The transistor can include a silicided source region, a silicided drain region, and a gate structure having the T-shaped gate conductor. The T-shaped gate conductor has a silicided top portion. The silicided top portion can have different silicidation characteristics than the silicided source region and the silicided drain region.
Abstract:
A method for suppressing silicidation retardation effects caused by high dopant concentrations, in particular high Arsenic concentrations, at the surface of a semiconductor substrate. The method includes implanting a preamorphization substance into the substrate to define the boundary of the source/drain, then implanting the dopant at high energy to establish a dopant concentration peak that is distanced from the surface of the substrate. The dopant is activated by rapid thermal annealing, with the relatively deep dopant concentration peak facilitating subsequent improved formation of silicide on the surface of the substrate.
Abstract:
A method of forming a dielectric gate insulator in a transistor is disclosed herein. The method includes providing a gate structure including a layer of material over a semiconductor structure, siliciding the substrate, and transforming the layer of material into a gate dielectric material. The gate dielectric material can be a high-k gate dielectric material.
Abstract:
A MOSFET with raised source/drains that can readily be silicidated and have shallow source/drain extensions. The invention uses chemical vapor epitaxy to create raised source/drains. The invention provides molecules containing silicon and molecules containing germanium, preferably GeH4, for the chemical vapor epitaxy. Initially, the concentration of GeH4 is between 5 to 10% of the concentration of molecules containing silicon. During the chemical vapor epitaxy, the concentration of GeH4 is reduced to zero. The raised source/drains and the gate are subjected to silicidation. The higher concentrations of GeH4 allow more selective epitaxy to silicon, thus preventing deposition on the polysilicon gate, nitride spacers and isolation trenches. It also allows for the use of lower epitaxy temperatures reducing movements of dopants in the source/drain extension. The slow reduction in concentration of GeH4 allows for the epitaxy temperature to be kept low. The reduced germanium concentration near the end of the epitaxy allows better silicidation of the raised source/drain.
Abstract:
A semiconductor device and a method of forming same are disclosed. The device includes an SOI wafer including a semiconductor layer, a substrate and a buried insulator layer therebetween; the semiconductor layer including a source region, a drain region, and a body region disposed between the source and drain regions, the source and drain regions including respective source and extensions which extend partially laterally inwardly towards one another above the body region; and, a gate on the semiconductor layer disposed above the body region, the gate being operatively arranged with the source, drain, and body regions to form a transistor; wherein the source and drain regions include source and drain deep doped regions on opposite sides of and laterally spaced from the gate and laterally adjacent to the respective source and drain extensions, and wherein the source and drain extensions include respective source and drain silicide extension portions disposed therein of a first thickness and the source and drain deep doped regions include respective source and drain silicide deep portions disposed therein of a second thickness relatively thicker than the first thickness.
Abstract:
A method of manufacturing an integrated circuit utilizes solid phase epitaxy to form a channel region. The method includes providing an amorphous semiconductor material including germanium, crystallizing the amorphous semiconductor material via solid phase epitaxy, and doping to form a source location and a drain location. The semiconductor material containing germanium can increase the charge mobility associated with the transistor.