Pressure free nanoimprinting lithography using ladder-type HSQ material for LSPR biosensor chip

We present an ingenious pressure free NIL (Nanoimprint lithography) method by simply employing a very thin PDMS mold along with a Spin-on-Glass HSQ material. Fabricating nano-patterns (i.e. nano-gratings and 2 D nano-arrays) via NIL is advantageous for LSPR based biosensors for producing large working area with high-throughput. Unlike conventional NIL and other fabrication methods, no complicated equipment is required in this work; only a simple heating plate (at 100 °C) was utilized for curing time reduction. Nano-pillar structure with definition down to 50-100 nm has been successfully fabricated using this method. After Au-deposition, mushroom like Au-capped nano-pillar chip has been successfully validated as a LSPR bio-sensor chip for IgA detection. In addition, this method provides promising features for higher dimensional structures fabrication which is considered as a beneficial tool for LSPR based biosensor sensitivity enhancement.