If $\mathrm{P}$ is Passivation, $\mathrm{Q}$ is $n$-well implant, $\mathrm{R}$ is metallization and $S$ is source/drain diffusion, then the order in which they are carried out in a standard $n$-well CMOS fabrication process, is
- P-Q-R-S
- Q-S-R-P
- R-P-S-Q
- S-R-Q-P