A 171k-LUT Nonvolatile FPGA using Cu Atom-Switch Technology in 28nm CMOS

A nonvolatile FPGA using atom-switch crossbars is implemented in a 28nm CMOS. The depopulated atom-switch crossbar with double-gate layout achieves 75% area saving. The routability degradation due to the depopulation is mitigated by a modified routing architecture of mixed segment lengths with thinning out connection block populations. To our knowledge, the novel FPGA provides the largest logic capacity of 171k lookup-table (LUT) among 3D-FPGAs based on monolithically integrated nonvolatile switch and memory. The operating frequency and dynamic power are significantly improved as compared to conventional atom-switch FPGAs.