CMOS-MEMS integration with through-chip via process

A method comprising:

• fabricating a CMOS structure on a first substrate, including at least one CMOS device and at least one conducting layer;
• fabricating a cap structure by forming one or more cavities in a cap wafer;
• fabricating a MEMS structure over the first substrate, including at least one MEMS device;
• bonding the MEMS structure to the cap structure such that the one or more cavities are facing the MEMS device;
• and
• forming a via in the cap structure, wherein the via extends to a silicon pillar that is directly over the at least one conducting layer of the CMOS structure, and wherein the via also extends over a top side of the cap structure, such that the via forms a conductive path from the top side of the cap structure to the at least one conducting layer of the CMOS structure through the silicon pillar.

A method comprising:

• fabricating a CMOS-MEMS structure that includes a CMOS structure and a MEMS structure, wherein the CMOS structure includes at least one CMOS device and at least one conducting layer;
• fabricating a cap structure by etching a first side of a cap wafer to form one or more cavities, with an isolation layer formed on the first side of the cap wafer;
• bonding the cap structure to the CMOS-MEMS structure;
• etching one or more trenches at a second side of the cap wafer;
• and
• depositing conductive material towards the second side of the cap wafer and surfaces of the one or more trenches, to form a conductive contact that passes through one of the trenches at the second side of the cap wafer and conductively connected to the at least one conducting layer of the CMOS structure.