Abstract:
A method for ultra-fine patterning of a semiconductor device performs a first, anisotropic etching of a hard mask layer according to a pattern created by lithographic techniques to create lines in the hard mask layer having an initial width. A second, anisotropic etching is performed on the hard mask layer to narrow the lines further than otherwise possible with a single etching according to the patterns created by lithography. Using the narrowed lines created in the hard mask layer, a third, anisotropic etching is performed, this time on the conductor layer shadowed by the narrow lines of the hard mask layer. The third etching creates narrow lines in the conductor layer in accordance with the narrow lines of the hard mask layer.
Abstract:
A method of fabricating a polysilicon gate 8 in a metal oxide semiconductor (MOS) transistor in an integrated circuit includes providing a metal layer 18, such as cobalt, on the sidewall 12 of the polysilicon gate 8, silicidizing the metal with the polysilicon in the polysilicon gate 8 to form a metal silicide sidewall 20, and removing the metal silicide sidewall 20 by etching.
Abstract:
A multilayer semiconductor structure includes a conductive via. The conductive via includes a pellet of metal having a high resistance to electromigration. The pellet is made from a conformal layer of copper or gold deposited over the via to form a copper or gold reservoir or contact located in the via. A barrier layer is provided between the reservoir and an insulating layer to prevent the pellet from diffusing into the insulating layer. The pellet can be formed by selective deposition or by etching a conformal layer. The conformal layer can be deposited by sputtering, collimated sputtering, chemical vapor deposition (CVD), dipping, evaporating, or by other means. The barrier layer and pellet may be etched by anisotropic dry etching, plasma-assisted etching, or other layer removal techniques.
Abstract:
A dual-metal CMOS arrangement and method of making the same provides a substrate and a plurality of NMOS devices and PMOS devices formed on the substrate. Each of the plurality of NMOS devices and PMOS devices have gate electrodes. Each NMOS gate electrode includes a first silicide region on the substrate and a first metal region on the first silicide region. The first silicide region of the NMOS gate electrode consists of a first silicide having a work function that is close to the conduction band of silicon. Each of the PMOS gate electrodes includes a second silicide region on the substrate and a second metal region on the second silicide region. The second silicide region of the PMOS gate electrode consists of a second silicide having a work function that is close to the valence band of silicon.
Abstract:
A dual-metal CMOS arrangement and method of making the same provides a substrate and a plurality of NMOS devices and PMOS devices formed on the substrate. Each of the plurality of NMOS devices and PMOS devices have gate electrodes. Each NMOS gate electrode includes a first silicide region on the substrate and a first metal region on the first silicide region. The first silicide region of the NMOS gate electrode consists of a first silicide having a work function that is close to the conduction band of silicon. Each of the PMOS gate electrodes includes a second silicide region on the substrate and a second metal region on the second silicide region. The second silicide region of the PMOS gate electrode consists of a second silicide having a work function that is close to the valence band of silicon.
Abstract:
A silicon-on-insulator substrate is disclosed which comprises: a silicon substrate layer; a first insulation layer over the silicon substrate layer; a conductive layer over the first insulation layer comprising at least one metal or metal silicide over the first insulation layer; a second insulation layer over the conductive layer; a silicon device layer comprising silicon over the second insulation layer; and at least one conductive plug through the silicon substrate layer and the first insulation layer contacting the conductive layer, or at least one conductive plug through the silicon device layer and the second insulation layer contacting the conductive layer. Also disclosed are methods for making silicon-on-insulator substrates having improved heat transfer structures.
Abstract:
A silicon-on-insulator substrate is disclosed which comprises: a silicon substrate layer; a first insulation layer over the silicon substrate layer; a conductive layer over the first insulation layer comprising at least one metal or metal silicide over the first insulation layer; a second insulation layer over the conductive layer; a silicon device layer comprising silicon over the second insulation layer; at least first conductive plug through the silicon substrate and the first insulation layer contacting the conductive layer; and at least one second conductive plug through the silicon device layer and the second insulation layer contacting the conductive layer. Also disclosed are methods for forming silicon-on-insulator substrates having improved stable ground characteristics.
Abstract:
A method of isolation of active islands on a silicon-on-insulator semiconductor device, comprising the steps of (a) providing a silicon-on-insulator semiconductor wafer having a silicon active layer, a dielectric isolation layer and a silicon substrate, in which the silicon active layer is formed on the dielectric isolation layer and the dielectric isolation layer is formed on the silicon substrate; (b) etching the silicon active layer to form an isolation trench wherein an unetched silicon layer at bottom of the isolation trench remains; (c) oxidizing the layer of silicon at the bottom of the isolation trench to a degree sufficient to oxidize through the layer of silicon at the bottom to the dielectric isolation layer; and (d) filling the isolation trench with a trench isolation material to form a shallow trench isolation structure.
Abstract:
In one embodiment, the present invention relates to a method of facilitating heat removal from a device layer of a silicon-on-insulator substrate comprising bulk silicon, an insulation layer over the bulk silicon, and a silicon device layer over the insulation layer involving forming at least one conductive plug comprising a conductive material within the bulk silicon and the insulation layer so as to contact the silicon device layer. In another embodiment, the present invention relates to a silicon-on-insulator structure, made of a silicon substrate layer; an insulation layer over the silicon substrate layer; a silicon device layer comprising silicon over the insulation layer; a conductive plug through the silicon substrate layer and the insulation layer contacting the silicon device layer; and a heat generating structure on the silicon device layer at least partially overlapping the conductive plug.
Abstract:
STI (Shallow Trench Isolation) structures are fabricated such that leakage current is minimized through a field effect transistor fabricated between the STI structures. The shallow trench isolation structure include a pair of isolation trenches, with each isolation trench being etched through a semiconductor substrate. A first dielectric material fills the pair of isolation trenches and extends from the isolation trenches such that sidewalls of the first dielectric material filling the isolation trenches are exposed beyond the top of the semiconductor substrate. A second dielectric material is deposited on the sidewalls of the first dielectric material exposed beyond the top of the semiconductor substrate. The second dielectric material has a different etch rate in an acidic solution from the first dielectric material filling the isolation trenches. The present invention may be used to particular advantage when the first dielectric material filling up the isolation trenches is comprised of silicon dioxide, and when the second dielectric material deposited on the sidewalls of the first dielectric material is comprised of silicon nitride. With the protective silicon nitride covering the sidewalls of the silicon dioxide filling the STI (shallow trench isolation) trenches, formation of divots is avoided in the silicon dioxide filling the STI (shallow trench isolation) trenches. Thus, when a field effect transistor is fabricated between such STI structures, silicides formed near the STI structures do not extend down toward the junction of the drain contact region and the source contact region of the field effect transistor such that drain and source leakage current is minimized.