Sputtering Al2O3 enhanced bandgap engineering for integrated photonic devices

We present experimental results of the application of Sputtering enhanced Quantum Well Intermixing (QWI) process, where the bandgap of InGaAsP/InP quantum well laser microstructure is effectively modified by intermixing quantum well and potential barrier layers through sputtering Al2O3-QWI. This technique creates point defects through plasma induced disordering in the process of sputtering Al2O3. The subsequent Rapid thermal Anneal (RTA) process is performed to increase the diffusion rate and quantum well intermixing. This results in an increased transitional energy and hence it modifies the bandgap essential for the development of next generation complex photonic integrated circuits (ICs). We report a large bandgap blue shift of 144 nm is achievable with a very high increase in photoluminescence (PL) intensity. The experimental results of the bandgap shifted waveguides and laser diodes are presented. Photoluminescence (PL) measurements of InGaAsP/InP laser structure were taken before and after Al2O3-QWI process. The proposed technique can provide reliable and fast post-growth wafer level fabrication of photonic devices monolithically.

Automated summary

This paper presents experimental results of the application of sputtering enhanced Quantum Well Intermixing (QWI) process to modify the bandgap of InGaAsP/InP quantum well laser microstructure. Point defects are created through plasma induced disordering in the process of sputtering Al2O3. Rapid thermal anneal (RTA) process is performed to increase the diffusion rate and achieve quantum well intermixing. The proposed technique provides reliable and fast fabrication of photonic devices at the wafer level.