Hydrogen silsesquioxane

When exposed to electrons or extreme ultraviolet radiation (EUV), HSQ cross-links via hydrogen evolution concomitant with Si-O bond crosslinking.

Recently, the possibility of crosslinking HSQ using ultrashort laser pulses through multiphoton absorption and its application to 3D printing of silica glass have been demonstrated.

[3][4] 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).

The nanoscale patterning capabilities and low-k of the Si rich oxide produced is potentially of broad scope of nano applications and devices.

[6][7] HSQ solutions derived from AQM dry silone resin are available in the United States from DisChem, Inc in concentrations ranging from 1-20% in MIBK[8] under the brand name H-SiQ.