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Hafnium Selenide |
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Hafnium Selenide is
generally immediately available in most volumes. High purity, submicron and nanopowder forms may be considered. Additional technical, research and safety (MSDS) information is available as is a Reference Calculator for converting relevant units of measurement.
Hafnium is a Block D, Group 4, Period 6 element. The electronic configuration is [Xe] 4f14 5d2 6s2. In its elemental form hafnium's CAS number is 7440-58-6. The hafnium atom has a radius of 156.4.pm and it's Van der Waals radius is 200.pm. Hafnium is one of the Group IV transition elements that is refined from various zirconic mineral deposits. Hafnium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity); metals in the form of foil, sputtering target, and rod, and compounds as submicron and nanopowder. It's primary uses are due to its ability as a nuclear "getter" or absorber of neutrons. It is a primary component in nuclear control rods for this purpose. It also finds uses as a dopant in the alloy of steel and titanium. It is also used in the production of mantles for high intensity incandescent lamps. Hafnium is replacing polysilicon as the principle gate or electrode material in metal oxide semiconductor field effect transistors (MOSFETs) which are the basis for all modern semiconductors. As semiconductors have gotten smaller, the limiting factor in further size reduction has been the ability of the silicon oxide gate to perform below 10 angstroms where leakage occurs. Recent research has been devoted to the development of High-k materials which can function as a di-electric barrier or gate with lower leakage. Using hafnium based alloys as this di-electric gate has allowed for the development of MOSFET gates smaller than 10 angstroms. This allows for further size reduction, reduced switching power requirements and improved performance. Selenium is a Block P, Group 16, Period 4 element. The electronic configuration is [Ar] 3d10 4s2 4p4. In its elemental form selenium's CAS number is 7782-49-2. The selenium atom has a radius of 116.pm and it's Van der Waals radius is 190.pm. Selenium exhibits both photovoltaic action, where light is converted directly into electricity, and photoconductive action, where the electrical resistance decreases with increased illumination. These properties make selenium useful in the production of photocells and exposure meters for photographic use, as well as solar cells. Below its melting point, selenium is a p-type semiconductor and has many uses in electronic and solid-state applications. Selenium is available as metal and compounds with purities from 99% to 99.9999% (ACS grade to ultra-high purity); metals in the form of foil, sputtering target, and rod, and compounds as submicron and nanopowder. Selenium was first discovered by Jons Berzelius in 1817. American Elements semi conducting materials are crystal structures produced from ultra high purity starting materials synthesized by our high purity production facility which includes several large electric muffle furnaces, a tube furnace for hydrogen reduction, 50 gallon glass-lined Pfaudler reactors supported by our analytical laboratory containing X-ray diffraction, SEM, AA, BET surface area, and ICP Spectrometry for trace metals analysis. See a discussion of American Elements Ultra High Purity and Analytical capabilities. See Crystal Growth for processes used to fabricate semiconductor materials, which include:
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