Hafnium(IV) silicate

Hafnium silicate is the hafnium(IV) salt of silicic acid with the chemical formula of HfSiO4.

Hafnium(IV) silicate
Names
Preferred IUPAC name
Hafnium(IV) silicate
Systematic IUPAC name
Hafnium(4+) silicate
Identifiers
3D model (JSmol)
ChemSpider
Properties
HfO4Si
Molar mass 270.57 g·mol−1
Appearance Tetragonal crystal[1]
Density 7.0 g/cm3
Melting point 2,758 °C (4,996 °F; 3,031 K) [1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Thin films of hafnium silicate and zirconium silicate grown by atomic layer deposition, chemical vapor deposition or MOCVD, can be used as a high-k dielectric as a replacement for silicon dioxide in modern semiconductor devices.[2] The addition of silicon to hafnium oxide increases the band gap, while decreasing the dielectric constant. Furthermore, it increases the crystallization temperature of amorphous films and further increases the material's thermal stability with Si at high temperatures.[3] Nitrogen is sometimes added to hafnium silicate for improving the thermal stability and electrical properties of devices.

Natural occurrence

Hafnon is the natural form of hafnium orthosilicate. Its name suggests the mineral is the Hf analogue of much more common zircon. Hafnon is the only currently known confirmed mineral of hafnium (i.e., hafnium-dominant one). Hafnon and zircon form a solid solution. Hafnon is a solely pegmatitic mineral and it occurs in largely fractionated (complex-genesis/history) pegmatites. [4]

gollark: I should assign unique IDs to the other sandbox escape bugs.
gollark: My "fix" is this:```lua--[["Fix" for bug PS#E9DCC81BSummary: `pcall(getfenv, -1)` seemingly returned the environment outside the sandbox.Based on some testing, this seems like some bizarre optimization-type feature gone wrong.It seems that something is simplifying `pcall(getfenv)` to just directly calling `getfenv` and ignoring the environment... as well as, *somehow*, `function() return getfenv() end` and such.The initial attempt at making this work did `return (fn(...))` instead of `return fn(...)` in an attempt to make it not do this, but of course that somehow broke horribly. I don't know what's going on at this point.This is probably a bit of a performance hit, and more problematically liable to go away if this is actually some bizarre interpreter feature and the fix gets optimized away.Unfortunately I don't have any better ideas. Also, I haven't tried this with xpcall, but it's probably possible, so I'm attempting to fix that too.]]local real_pcall = pcallfunction _G.pcall(fn, ...) return real_pcall(function(...) local ret = {fn(...)} return unpack(ret) end, ...)end local real_xpcall = xpcallfunction _G.xpcall(fn, handler) return real_xpcall(function() local ret = {fn()} return unpack(ret) end, handler)end```which appears to work at least?
gollark: Fixed, but I don't really know how or why.
gollark: ... should I create a bug report?
gollark: It returns two, actually. The second one. I don't know *what* the first one is doing.

References
  1. Haynes, William M., ed. (2011). CRC Handbook of Chemistry and Physics (92nd ed.). Boca Raton, FL: CRC Press. p. 4-66. ISBN 1439855110.
  2. Mitrovic, I.Z.; Buiu, O.; Hall, S.; Bungey, C.; Wagner, T.; Davey, W.; Lu, Y. (April 2007). "Electrical and structural properties of hafnium silicate thin films". Microelectronics Reliability. 47 (4–5): 645–648. doi:10.1016/j.microrel.2007.01.065.
  3. J.H. Choi; et al. (2011). "Development of hafnium based high-k materials—A review". Materials Science and Engineering: R. 72 (6): 97–136. doi:10.1016/j.mser.2010.12.001.
  4. https://www.mindat.org/min-1792.html


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