Figure 3
From: Highly efficient thin-film 930 nm VCSEL on PDMS for biomedical applications
The fabrication process of the thin-film VCSEL transferred onto a PDMS substrate. (a) p-on-n structure of the thin-film VCSEL is grown in upward order using an MOCVD system. (b) The front-end process is performed including front pattern formation, top-contact (Ti/Pt/Au) metallization, and mesa etching. Subsequently, the front-processed VCSEL is bonded to the sapphire carrier using an Apiezon W wax. (c) The 350-μm n-GaAs substrate is removed by the NH4OH-based etchant. (d) Thin-film VCSEL with Ni/AuGe/Ni/Au is coupled to a PDMS with a metal strip via an SMB technique. (e) The top-emitting thin-film 930 nm VCSEL is fabricated onto a PDMS by removing the sapphire carrier.
