Micro-electro mechanical system device containing a bump stopper and methods for forming the same

A micro-electro mechanical system (MEMS) device, comprising:

• a MEMS substrate;
• a first chamber containing a first movable element and laterally confined within a matrix layer that overlies the MEMS substrate;
• a matrix-side bonding dielectric layer located on a top surface of the matrix layer;
• a cap substrate overlying the matrix layer and comprising a proximal horizontal surface and a vertically raised horizontal surface that is raised above the proximal horizontal surface;
• a cap-side bonding dielectric layer that is located on the proximal horizontal surface and on the vertically raised surface, wherein a portion of the cap-side bonding dielectric layer located on the proximal horizontal surface is bonded to the matrix-side bonding dielectric layer;
• and
• a bump-containing material layer located underneath a portion of the cap-side bonding dielectric layer located on the vertically-raised surface and comprising an array of downward-protruding bumps.

A micro-electro mechanical system (MEMS) device, comprising:

• a MEMS substrate;
• a matrix layer that overlies the MEMS substrate;
• and
• a cap substrate bonded to the matrix layer and comprising inverted trenches therein,
• wherein:
• a first movable element is located inside a first chamber that is laterally bounded by the matrix layer and vertically bounded by a first capping surface that overlies the first movable element;
• the first capping surface comprises an array of downward-protruding bumps including respective portions of a bump-containing material layer;
• and
• the inverted trenches overlie the first capping surfaces and extend upward into the cap substrate.