Wafer level integrated mems device enabled by silicon pillar and smart cap

A method, comprising:

• forming a capping substrate comprising a ventilation trench within the capping substrate;
• forming a lining structure including an oxide layer on sidewalls of the ventilation trench and a polysilicon layer over the oxide layer, the lining structure leaving an opening hat defines a vent extending to a first height as measured from a lower surface of the capping substrate to an upper surface of the ventilation trench;
• forming a sealing structure within the ventilation trench;
• forming first and second recessed regions laterally spaced apart from the sealing structure, an uppermost extent of the recessed regions being at a second height that is less than the first height;
• providing a device substrate comprising first and second micro-electro mechanical system (MEMS) devices;
• bonding the capping substrate to the device substrate hermetically sealing a first cavity at a first gas pressure associated with the first MEMS device and the first recess region, and defining a second cavity associated with the second MEMS device and the second recess region, wherein the second cavity is in fluid communication with the vent;
• and
• adjusting a gas pressure in the second cavity through the vent and sealing the vent hermetically at a second gas pressure that is different than the first gas pressure of the first cavity.

A method, comprising:

• providing a device substrate comprising first and second micro-electro mechanical system (MEMS) devices;
• forming a capping substrate comprising a ventilation trench extending from a front side of the capping substrate to a position within the capping substrate;
• before bonding the device substrate to the capping substrate, forming a sealing structure within the ventilation trench, the sealing structure defining a vent within the capping substrate, wherein the sealing structure includes an overhang meeting at the front side of the capping substrate and sealing the ventilation trench from top;
• bonding the device substrate to the capping substrate hermetically sealing a first cavity associated with the first MEMS device and a second cavity associated with the second MEMS device, wherein the second cavity is in fluid communication with the vent;
• adjusting a gas pressure of the second cavity to a second gas pressure;
• and
• sealing the vent hermetically at the second gas pressure that is different than a first gas pressure of the first cavity.

A method, comprising:

• providing a device substrate comprising first and second micro-electro mechanical system (MEMS) devices;
• providing a capping substrate, wherein laterally spaced apart isolation trenches separated by a silicon region are concurrently formed with a ventilation trench and having a height substantially equal to a height of the ventilation trench;
• forming a sealing structure within the ventilation trench and the isolation trenches, the sealing structure filing the isolation trenches and defining a vent within the ventilation trench;
• forming first and second recessed regions laterally spaced apart from the ventilation trench and the isolation trenches;
• bonding the device substrate to the capping substrate at a first gaps pressure and hermetically sealing a first cavity associated with the first MEMS device and a second cavity associated with the second MEMS device, wherein the second cavity is in fluid communication with the vent;
• and
• thinning the capping substrate to open the vent and adjusting a gas pressure of the second cavity to a second gas pressure different than the first gas pressure.