Alignment Accuracy in a MA/BA8 Gen3 Using Substrate Conformal Imprint Lithography (SCIL)
Substrate Conformal Imprint Lithography (SCIL) originally invented by Philips Research is an innovative nanoimprint technology. With this technology substrates up to 200 mm can be patterned with features down to a few nanometer resolution, delivering a unique uniformity of the imprint and the residual layer. The SCIL process was implemented as an option in a standard SUSS Mask Aligner in 2009 and is available on MA/BA6, MA/BA6 Gen3 and MA/BA8 Gen3 (Figure 1). The SCIL technology uses a three layer stamp for structure transfer (see Figure 3 and Figure 4). This stamp is composed of a thin glass back plate (~200 μm), a soft PDMS buf fer layer (~500 μm) and a high modulus PDMS layer (100 μm) with the structur es to be transferred. With this setup of the stamp absolute distortions like magnification errors but also the relative distortions due to elastic deformation during the imprint are minimized. Furthermore distortions of the structures during the imprint process are avoided by using only a small imprint pressure (20 mbar) and mainly capillary forces to pull the stamp into the resist layer.