Hi Just wondering why is it called gf180 while Lmin = 280n?

Marketing? : ) No, actually the reason is that the wafers are processed on the same line as other GF180 process variants. However, the MCU variant has a base thick oxide, and a thicker oxide on top of that for the 5V-6V devices, so the devices are all very large compared to the standard GF 180 BCD process.