Study of process of HSQ in electron beam lithography

As a kind of inorganic negative-tone resist in electron beam lithography, hydrogen silsesquioxane(HSQ) has a high pattern resolution of about 5 nm, but the poor sensitivity limits its extensive application in the field of micro-fabrication. It's very difficult to fabricate the high aspect-ratio dense resist pattern for HSQ because of backscattering electrons and proximity effect. The methods by optimizing process condition are proposed to improve the contrast of graphic structure of HSQ resist and restrain electron beam proximity effect at the same time. On 450nm thick resist layer, HSQ resist pillar array pattern with 5 aspect-ratio under 50kv voltage and HSQ resist mesh pattern structure with 9 aspect-ratio under 100kv voltage can been achieved with optimization of process condition.