Fabrication and integration of nanobolometer sensors on a MEMs process

In this work, we combine electron beam lithography (EBL) with conventional microscale metal deposition and etch process technologies, to create bolometer devices with nanoscale feature critical dimensions (CDs). We report the creation of titanium (Ti) bolometer devices with 70 nm minimum feature CDs, and total bolometer film thicknesses ranging between 60 nm and 150 nm. Our new nanobolometer devices are integrated with conventional CMOS/MEMs fabrication technologies, creating thermally isolated sensors with nanoscale feature sizes on a 0.5 μm CMOS base process. We also present temperature coefficient of resistance (TCR) data for the new devices, and show a nanobolometer TCR performance of 0.22%/K at 70 nm CDs, comparable to microscale bolometer devices.