Hydrogen silsesquioxane

Manfrinato, V. R., Cheong, L. L., Duan, H., Winston, D., Smith, H. I., and K. K. Berggren. 2011. Sub-5 keV electron-beam lithography in hydrogen silsesquioxane resist. Microelectronic Engineering... 

ACRONYMS, ALTERNATIVE NAMES, TRADE NAME HSQ, LPHSQ, hydridosilsesquioxane, hydrogen silsesquioxane, polyhydrosilsesquioxane, FOx (Dow Corning Corp.)... 

Hessel CM, Henderson EJ, Veinot JGC (2006) Hydrogen silsesquioxane a molecular precursor for nanocrystalline Si-Si02 composites and freestanding hydride surface terminated silicon nanoparticles. Chem Mater 18 6139-6146... 

Scheme 13.8 Molecular structure of hydrogen silsesquioxane (HSQ) before cross-linking...

Peuker M, Lim M, Smith HI et al (2002) Hydrogen silsesquioxane, a high-iesolution negtive tone e-beam resist, investigated for its applicability in photon-based lithographies. Microelectron Eng 61 803-809... 

Mohammad M, Dew S, Evoy S et al (2011) Fabrication of sub-10 nm silicon carbon nitride resonators using a hydrogen silsesquioxane mask patterned by electron beam lithography. Microelectron Eng 88 2338-2341... 

Henschel W, Georgiev Y, Kurz H (2003) Study of a high contrast process for hydrogen silsesquioxane as a negative tone electron beam resist. J Vac Sci Technol, B Micro-electron Nanometer Struct 21 2018... 

A bilayer resist consisting of hydrogen silsesquioxane and Novolac was investigated for fabricating high-aspect-ratio structures. In the bilayer combination, the silicon-containing top layer allowed nanoscale structures with aspect ratios exceeding 15 to be etched into the hard-baked Novolac bottom layer. 

The synthesis of monolithic materials with built-in reactive sites opens up the opportunities for exploiting their reactivity for desired piuqroses with precision. In this context, hydrosilanes containing reactive Si—H bonds in monomeric and polymeric forms have been used for the reduction of organic compounds [60]. Therefore, as a solid material hydrogen silsesquioxane (H—SiOi s, HSQ) represents a reactive solid for which the reactivity can be used for desired purposes. However, the synthesis of monolithic HSQ directly from alkoxide precursor (tri-methoxy/ethoxysilane) is rather difficult, as the Si—H bond is very weak and can easily be cleaved imder basic and nucleophilic conditions, restricting the sol-gel only to the acid-catalyzed route, and only the synthesis of HSQ films and periodic mesoporous particles has been reported so far [61]. 

Moitra, N., Kanamori, K., Shimada, T., Takeda, K., Ikuhara, Y.H., Gao, X., and Nakanishi, K. (2013) Synthesis of hierarchically porous hydrogen silsesquioxane monoliths and embedding of metal nanoparticles by on-site reduction. Adv. Funct. Mater., 23, 2714-2722. 

Figures (a) Schematic illustration of the use of hydrogen silsesquioxane (HSQ) nanoposts to provide long-range order for a PS-b-PDMSfilm. (b) SEM micrograph of a poorly ordered monolayer of spherical domains formed on a flat surface, (c and d) SEM images of ordered block copolymer spheres formed within a sparse 2D lattice posts (brighter dots) prepared by electron-beam (e-beam) lithography.

Thermally curable materials such as poly(benzene-dicar-boxylic-diallylesters), PDMS, ° hydrogen silsesquioxane (HSQ), or spin-on glasses (SOGs), " " and many commercial resists have been successfully imprinted. Sevaal thermally curable resists that are commercially available are based on allyl prepolymers and begin to thermally aosslink to form poly(diallylphthalate) (PDAP) at temperatures greata than 120-140 This type of thermally curable material has... 

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