EML Based on Lumped Configuration, Identical Epitaxial Layer and HSQ Planarization

We present a new electro-absorption modulated laser based on a lumped configuration, identical epitaxial layer scheme, and a new low-permittivity planarization method. The design of the device is intended to offer a high modulation frequency using a simple and cheap fabrication process. A thick-film of HSQ spinon coating was used to planarize the device and enable a low capacitance contact to the p-side. A $6- \mu \mathrm{m} -$thick planarized HSQ layer was fabricated and used to implement the electrode to the electroabsorption modulator.