Study of laser-based transfer of graphene via laser induced transfer process for the on-chip integration of photodetector

Currently the most widely graphene production technique is growth via Chemical Vapor Deposition (CVD) on copper thin films previously deposited by evaporation on sapphire substrates, which can yield high-quality monolayer graphene coatings. However, the transfer of graphene from the growth substrate via conventional methods making use of support/protective layers (e.g., organic polymers), lithographic masking layers and chemical etching, is a multi-step complex procedure. Here, we report the use of laser-based transfer technique, namely, Laser-Induced Forward Transfer (LIFT) for the reliable, reproducible and high-quality transfer of graphene pixels at designated areas on SiO₂/Si substrates, directly from the growth substrate. LIFT is an environmentally friendly, mask-less technique and offers high resolution with high throughput. The quality of the transferred films has been inspected via SEM, Raman spectroscopy, and AFM characterization. Electrical characterization for mobility measurement will also be performed. The aim of this study is the process optimization of LIFT process parameters, such as the laser fluence. The reported results highlight the advantages of the laser-based monolayer graphene deposition methods for the on-chip integration of graphene-based photodetectors.