Photovoltaic thermoelectric hybridization is a pathway to produce electric power using the heat generated in a photovoltaic cell as a heat source for a Seebeck thermoelectric generator. However, previous studies showed the need to reduce the thermal resistance between the photovoltaic cell and the thermoelectric generator to achieve high power conversion efficiency. To minimize this thermal resistance, we propose in this study a method for transferring the cell onto a custom copper substrate and removing the growth substrate from the epitaxial layer by Au-Au interdiffusion bonding and full substrate etching. Using various characterization methods, we identify the challenges in each process step for upscaling this process on a larger surface. The first cell transfer attempt achieved a mirror-like surface roughness on the epitaxial layer. Analysis of the defects caused by the bonding and the etching step allow us to identify optimizations to apply the process to the centimeter-scale areas