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;
• at least one movable element laterally confined within a matrix layer that overlies the MEMS substrate;
• and
• a cap substrate bonded to the matrix layer, wherein:
• a first movable element selected from the at least one 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 cap substrate comprises a vertically raised horizontal surface that overlies the first chamber,
• wherein inverted trenches vertically extend upward from a vertically raised horizontal surface of the cap substrate into the cap substrate.

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

• a MEMS substrate;
• at least one movable element laterally confined within 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 selected from the at least one 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;
• and
• inverted trenches overlie the first caping surfaces and extend upward into the cap substrate.