Patent ID: 9725304
Date: 2017-08-08
CPC Classifications: B81B,B81C,H01L

Claim:
1. A semiconductor device having multiple MEMS (micro-electro mechanical system) devices, comprising: a semiconductor substrate having a first MEMS device and a second MEMS device; an encapsulation substrate having a top portion and sidewalls forming a first cavity and a second cavity, the encapsulation substrate being bonded to the semiconductor substrate with a bonding material at a lower end of the sidewalls to encapsulate the first MEMS device in the first cavity and to encapsulate the second MEMS device in the second cavity; wherein the second cavity includes at least one access channel at a recessed region below a first sidewall of the encapsulation substrate adjacent to an interface between the encapsulation substrate and the semiconductor substrate, the access channel being disposed below a bottom portion of the first sidewall without the bonding material; and a thin film covering the access channel to seal the second cavity; wherein the first cavity is at a first atmospheric pressure and the second cavity is at a second atmospheric pressure, wherein the second atmospheric pressure is different from the first air pressure.