Adhesive Polymer Bonding Method for Integration of III-V Thin-Film Optoelectronic Devices Onto Silicon Substrate

This paper demonstrates the integration of thin-film III-V compound semiconductor devices onto silicon-based host substrate using an adhesive polymer bonding technique. A thermoplastic polymer, Polymethyl methacrylate, was employed as the bonding layer due to its low curing temperature and capability to provide uniform contact between bonding surfaces without significant bonding pressures. This enables the proposed integration of ultrathin devices with potential of low-cost, low-temperature, yet simple processing. The III-V semiconductor-based thin-film devices were separately fabricated from their preferred growth substrate utilizing epitaxial lift-off technique. A
$2 \times 2$
array of thin-film devices was integrated by the proposed approach. 3-D topology of the integrated devices was studied by optical profilometer. Scanning electron microscope images of the bonding interfaces were discussed to present the uniform contact between thin-film device and bonding layer. Post-processing to the silicon substrate with integrated devices was also investigated to provide insights on layer-by-layer integration for complex and advanced integrated microsystems.