200px, thumbnail, Hydrogen silsesquioxane (R = H). Hydrogen silsesquioxane(s) (HSQ, H-SiO_x, T^H_n, H-resin) are inorganic compounds with the empirical formula SiO_3/2sub>n. The cubic H₈Si₈O₁₂ (T^H₈) is used as the visual representation for HSQ. T^H₈, T^H₁₀, T^H₁₂, and T^H₁₄ have been characterized by EA), gas chromatography–mass spectroscopy ( GC-MS), IR spectroscopy, and

NMR spectroscopy Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique to observe local magnetic fields around atomic nuclei. The sample is placed in a magnetic fiel ...

. High purity semiconductor-grade HSQ has been investigated as a negative

resist A resist, used in many areas of manufacturing and art, is something that is added to parts of an object to create a pattern by protecting these parts from being affected by a subsequent stage in the process. Often the resist is then removed. For ...

photolithography In integrated circuit manufacturing, photolithography or optical lithography is a general term used for techniques that use light to produce minutely patterned thin films of suitable materials over a substrate, such as a silicon wafer, to protect ...

and electron-beam (e-beam) lithography. HSQ is commonly delivered in

methyl isobutyl ketone Methyl isobutyl ketone (MIBK) is the common name for the organic compound 4-methylpentan-2-one, condensed chemical formula (CH3)2CHCH2C(O)CH3. This colourless liquid, a ketone, is used as a solvent for gums, resins, paints, varnishes, lacquers, and ...

( MIBK) and can be used to form 0.01–2 µm films on substrates/wafers. When exposed to electrons or extreme ultraviolet radiation (

EUV Extreme ultraviolet radiation (EUV or XUV) or high- energy ultraviolet radiation is electromagnetic radiation in the part of the electromagnetic spectrum spanning wavelengths from 124 nm down to 10 nm, and therefore (by the Planck ...

), HSQ cross-links via hydrogen evolution concomitant with Si-O bond

crosslink In chemistry and biology a cross-link is a bond or a short sequence of bonds that links one polymer chain to another. These links may take the form of covalent bonds or ionic bonds and the polymers can be either synthetic polymers or natural ...

ing. Sufficiently dosed and exposed regions form a low dielectric constant (low-k) Si rich oxide that is chemically resistant/insoluble towards developers, such as tetramethylammonium hydroxide ( TMAH). Sub-10 nm patterning is achievable with HSQ. The nanoscale patterning capabilities and low-k of the Si rich oxide produced is potentially of broad scope of nano applications and devices. HSQ has been available as 1 and 6% (wt%) MIBK solutions from Dow Inc. (Formally Dow Corning), called XR-1541-001 and XR-1541-006, respectively. HSQ in MIBK has a short shelf life. Alternatively, Applied Quantum Materials Inc. (AQM) produces HSQ with a longer shelf life.^, AQM HSQ solutions are available in the United States from DisChem, Inc.

References

Optical materials {{material-stub

Further reading

References