E-beam lithography using dry powder resist of hydrogen silsesquioxane having long shelf life

This is the authors' abstract. We don't add key points for this paper.

Hydrogen silsesquioxane (HSQ) is arguably the most popular negative e-beam resist for academic research. One of the most significant advantages of HSQ is its ultrahigh resolution. However, it has a short shelf life, which increases its cost. As an alternative, a new type of dry powder HSQ resist resin (Applied Quantum Materials, referred to as AQM) was introduced here, the shelf life of which can be considered as infinitely long. A small amount of the powder can be dissolved in a solvent as needed right before exposure. Furthermore, this powder HSQ resist has a similar resolution and sensitivity parameters. By using the high-contrast development process with a salty developer, a 7.5 nm half-pitch nested “L” shape structure is achieved.