Green Poly-Si TFTs: RF Breakthroughs $(f_{\mathrm{T}}/f_{\max}= 63.6/30\ \text{GHz})$ by an Ingenious Process Design for IoT Modules on Everything

We report an ingenious, low-temperature process platform for the fabrication of high-performance RF poly-Si TFTs with cut-off frequency
$(f_{\mathrm{T}})$
of 63.6 GHz and maximum oscillation frequency
$(f_{\max})$
of 30 GHz, the highest values ever reported in poly-Si devices. The superior RF performance is achieved by an exquisite combination of large-grain poly-Si channel, T-shaped gate, sidewall air-spacers, and silicide electrodes, using nanosecond-pulsed green laser anneal, high etching selectivity, novel silicidation process by design, and microwave annealing for S/D dopant activation. Our reported poly-Si TFTs are a strong competitor against standard
$0.35\mu \mathrm{r}$
SOI CMOS devices, enabling a viable, cost-effective approach for a vast landscape of IoT and More-than-Moore applications.