Intel launched its first processors with High-k Metal Gate (HKMG) transistors on a 45nm process in 2007 and over the years foundries adopted it too. TSMC followed in 2012, Samsung in 2014 and now news reaches us that UMC just mastered HKMG as well with the arrival of MDM9625 LTE modem fabbed on a 28nm process for Qualcomm.
Intel ventured into gate-last HKMG transistors in 2007 with their 45nm node processors, followed by TSMC in 2012 and Samsung in 2014. We at TechInsights note that both Samsung and GlobalFoundries began their metal gate transistors with a gate-first process at their 32/28nm nodes and then later switched to the gate last process for their 20nm process nodes.
The two variants of the HKMG transistors are gate-first and gate-last, with the gate-last having an additional two versions: high-k first or high-k last. Intel’s 45nm HKMG process featured a high-k first gate-last fabrication sequence, while their 32nm process was a high-k last gate-last process.