Method for forming multi-depth mems package

A method for manufacturing a microelectromechanical systems (MEMS) package, the method comprising:

• preparing a cap substrate having a first device region, a second device region, and a scribe line region defined on the cap substrate;
• forming a first trench in the first device region, a second trench in the second device region, and a scribe trench in the scribe line region at a front side of the cap substrate, wherein the first trench, the second trench, and the scribe trench have the same depth;
• forming and patterning a hard mask over the cap substrate, wherein the hard mask has a first thickness in the scribe trench and a first portion of the first trench, and a second thickness smaller than the first thickness in the second trench and a second portion of the first trench;
• removing the hard mask from the scribe trench and performing an etch to the scribe trench to lower a bottom surface of the scribe trench;
• and
• removing the hard mask from the second trench and performing an etch to the scribe trench and the second trench to lower bottom surfaces of the scribe trench and the second trench, so as to generate a greater depth in the scribe trench than the second trench, and the second trench deeper than the first trench.

A microelectromechanical systems (MEMS) package comprising:

• a device substrate comprising first and second MEMS devices;
• and
• a cap substrate bonded to the device substrate, the cap substrate enclosing a first cavity overlying the first MEMS device and a second cavity overlying the second MEMS device;
• wherein the first cavity has a first depth with respect to a front-side surface of the cap substrate smaller than a second depth of the second cavity with respect to the front-side surface of the cap substrate;
• wherein a stopper is raised from a bottom surface of the first cavity to a position within the first cavity and vertically lower than the front-side surface of the cap substrate.