| Summary: | In this paper we present a comprehensive report on the issues found during the manufacturing of high-yield CMOS-MEMS sensors based on vapor-phase hydrogen fluoride (vapor-<inline-formula> <tex-math notation="LaTeX">$HF$ </tex-math></inline-formula>) oxide etching. During the study we have identified the main issues affecting CMOS-MEMS high-yield manufacturing regarding the silicon oxide as a sacrificial material, the passivation as a release mask, the BEOL as structural material for MEMS design and the aluminum-sputtering as a sealing layer for the MEMS cavity. This study has been carried out by systematically analyzing over 100 full wafers in 10 different runs on four different foundries using <inline-formula> <tex-math notation="LaTeX">${\mathrm {0.5~ \mu m }}$ </tex-math></inline-formula>, <inline-formula> <tex-math notation="LaTeX">${\mathrm {0.18~ \mu m }}$ </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">${\mathrm {0.15~ \mu m }}$ </tex-math></inline-formula> CMOS processes, containing both test structures and full-sensor designs.
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