63 results about "Fermi level pinning" patented technology

Nano-engineered structures are disclosed, incorporating nanowhiskers of high mobility conductivity and incorporating pn junctions. In one embodiment, a nanowhisker of a first semiconducting material has a first band gap, and an enclosure comprising at least one second material with a second band gap encloses said nanoelement along at least part of its length, the second material being doped to provide opposite conductivity type charge carriers in respective first and second regions along the length of the of the nanowhisker, whereby to create in the nanowhisker by transfer of charge carriers into the nanowhisker, corresponding first and second regions of opposite conductivity type charge carriers with a region depleted of free carriers therebetween. The doping of the enclosure material may be degenerate so as to create within the nanowhisker adjacent segments having very heavy modulation doping of opposite conductivity type analogous to the heavily doped regions of an Esaki diode. In another embodiment, a nanowhisker is surrounded by polymer material containing dopant material. A step of rapid thermal annealing causes the dopant material to diffuse into the nanowhisker. In a further embodiment, a nanowhisker has a heterojunction between two different intrinsic materials, and Fermi level pinning creates a pn junction at the interface without doping.

A semiconductor device and process including a high-k gate dielectric is described. A substrate is provided, and a high-k gate dielectric material, preferably amorphous HfSiON, is deposited over the substrate. In preferred embodiments, the high-k dielectric material includes nitrogen. In a preferred embodiment, a silicon nitride layer is deposited using jet vapor deposition (JVD) on the high-k dielectric material. When the JVD nitride layer is deposited according to preferred embodiments, the layer has a low density of charge traps, it maintains comparable carrier mobility and provides better EOT compared to oxide or oxynitride. A second nitrogen-containing layer formed between the high-k dielectric and the gate electrode acts as a diffusion barrier. It also reduces problems relating to oxygen vacancy formation in high-k dielectric and therefore minimizes Fermi-level pinning.

The invention provides a germanium-based NMOS (N-metal-oxide-semiconductor) device and a preparation method thereof, belonging to the technical field of ultra large scale integration (ULSI) circuit manufacturing. Two layers of insulation medium material are inserted among metal source and drain electrodes and a substrate of the germanium based-NMOS device, and the bottom layer is S medium material with high pinning coefficient, such as hafnium oxide, silicon nitride or hafnium silica, and the upper layer of medium material is delta EC medium material with low conduction band offset, such as titanium dioxide, gallium oxide or strontium titanium oxygen. According to the invention, the fermi energy level pinning effect can be weakened, the electronic potential barrier is reduced, and furtherthe performances of a germanium-based schottky NMOS device are improved; and compared with the traditional method in which a single layer of insulation medium material such as AL2O3 is adopted, the preparation method can be used for effectively reducing the schottky potential barrier and maintaining lower source and drain resistance, therefore, the performances of the device are improved to a large extent.

A structure of a MIS transistor for realizing a CMOS circuit capable of simultaneously achieving the high ON current and the low power consumption is provided. Each of the gate insulators of an n channel MIS transistor and a p channel MIS transistor is composed of a hafnium oxide (HfO2) film. Also, the gate electrode of the n channel MIS transistor is composed of an Ni (nickel) silicide film, and the gate electrode of the p channel MIS transistor is composed of a Pt (platinum) film. In this structure, Fermi level pinning of the gate electrodes can be prevented. Therefore, the increase of the threshold voltage of the n channel MIS transistor and the p channel MIS transistor can be inhibited.

The invention relates to a semiconductor device with high dielectric constant material, which includes a substrate and the high dielectric constant material formed on the substrate. The high dielectric constant material is preferably amorphous HfSiON. In a preferred embodiment, the high dielectric constant material contains nitrogen. In a preferred embodiment, the silicon nitride layer is formed on the high-k material using spray vapor deposition. After the deposition of this JVD nitride layer, this layer has a lower charge trap density and has comparable carrier mobility to oxide or oxynitride and better equivalent oxide thickness. The present invention may also include a second nitrogen-containing layer formed between the high dielectric constant material and the gate electrode as a diffusion barrier layer. The present invention reduces the problems caused by oxygen vacancies formed in high dielectric constant materials, thereby reducing the Fermi level pinning effect.

Nano-engineered structures are disclosed, incorporating nanowhiskers of high mobility conductivity and incorporating pn junctions. In one embodiment, a nanowhisker of a first semiconducting material has a first band gap, and an enclosure comprising at least one second material with a second band gap encloses said nanoelement along at least part of its length, the second material being doped to provide opposite conductivity type charge carriers in respective first and second regions along the length of the of the nanowhisker, whereby to create in the nanowhisker by transfer of charge carriers into the nanowhisker, corresponding first and second regions of opposite conductivity type charge carriers with a region depleted of free carriers therebetween. The doping of the enclosure material may be degenerate so as to create within the nanowhisker adjacent segments having very heavy modulation doping of opposite conductivity type analogous to the heavily doped regions of an Esaki diode. In another embodiment, a nanowhisker is surrounded by polymer material containing dopant material. A step of rapid thermal annealing causes the dopant material to diffuse into the nanowhisker. In a further embodiment, a nanowhisker has a heterojunction between two different intrinsic materials, and Fermi level pinning creates a pn junction at the interface without doping.

Complementary transistors and methods of forming the complementary transistors on a semiconductor assembly are described. The transistors are formed with an optional interfacial oxide, such as SiO2 or oxy-nitride, to overlay a semiconductor substrate which will be conductively doped for PMOS and NMOS regions. Then a dielectric possessing a high dielectric constant of least seven or greater (also referred to as a high-k dielectric) is deposited on the interfacial oxide. The high-k dielectric is covered with a thin monolayer of metal oxide (i.e., aluminum oxide, Al2O3) that is removed from the NMOS regions, but remains in the PMOS regions. The resulting NMOS transistor diffusion regions contain predominately metal to silicon bonds that create predominately Fermi level pinning near the valence band while the resulting PMOS transistor diffusion regions contain metal to silicon bonds that create predominately Fermi level pinning near the conduction band.

Complementary transistors and methods of forming the complementary transistors on a semiconductor assembly are described. The transistors are formed with an optional interfacial oxide, such as SiO2 or oxy-nitride, to overlay a semiconductor substrate which will be conductively doped for PMOS and NMOS regions. Then a dielectric possessing a high dielectric constant of least seven or greater (also referred to as a high-k dielectric) is deposited on the interfacial oxide. The high-k dielectric is covered with a thin monolayer of metal oxide (i.e., aluminum oxide, Al2O3) that is removed from the NMOS regions, but remains in the PMOS regions. The resulting NMOS transistor diffusion regions contain predominately metal to silicon bonds that create predominately Fermi level pinning near the valence band while the resulting PMOS transistor diffusion regions contain metal to silicon bonds that create predominately Fermi level pinning near the conduction band.