A 4.8-mW Label-free Frequency-shift 3×3×2 3D Biosensor Array with Vertically-stacked 60-GHz LC Oscillators in 22-nm CMOS

This paper shows a 3D ($3 \times 3 \times 2$) frequency-shift label-free biosensor array using vertically-stacked LC oscillators in 22 nm CMOS technology. The bio-sensing circuit is composed of the two 60-GHz LC oscillators and dividers that are necessary for extracting 60 GHz} output signals from the chip. The 0.04 mm
²
chip (0.0035 mm
²
. per single-element) measurement using thick and thin resin samples successfully demonstrated their vertical and horizontal detection in $60 \mu \mathrm{m} \times 60 \mu \mathrm{m} \times 4 \mu \mathrm{m}$ special resolution and 73 % fill factor consuming 4.8 mW under 1.2 V per the single-element.