Microelectromechanical systems device having a mechanically robust anti-stiction/outgassing structure

A method for forming a microelectromechanical system (MEMS) device, the method comprising:

• forming a silicon-based semiconductor layer over an interlayer dielectric (ILD) structure, wherein the ILD structure is disposed over a first semiconductor substrate;
• forming a patterned masking layer over the silicon-based semiconductor layer, wherein the patterned masking layer masks a first portion of the silicon-based semiconductor layer and a second portion of the silicon-based semiconductor layer, wherein the first portion of the silicon-based semiconductor layer is laterally spaced from the second portion of the silicon-based semiconductor layer;
• with the patterned masking layer in place over the silicon-based semiconductor layer, performing an etching process on the silicon-based semiconductor layer to remove unmasked portions of the silicon-based semiconductor layer, thereby leaving the first portion of the silicon-based semiconductor layer in place over the ILD structure as a sensing electrode and leaving the second portion of the silicon-based semiconductor layer in place over the ILD structure as an anti-stiction structure;
• forming a movable mass in a second semiconductor substrate;
• and
• bonding the second semiconductor substrate to the first semiconductor substrate, such that both the anti-stiction structure and the sensing electrode are disposed between the movable mass and the ILD structure.

A method for forming a microelectromechanical system (MEMS) device, the method comprising:

• forming a sensing electrode over an interlayer dielectric (ILD) structure, wherein the ILD structure is disposed over a first semiconductor substrate;
• forming an anti-stiction layer over the ILD structure and the sensing electrode, wherein the anti-stiction layer is a silicon-based semiconductor;
• performing an etching process on the anti-stiction layer to form a plurality of anti-stiction structures over the ILD structure, wherein the plurality of anti-stiction structures are laterally spaced from the sensing electrode;
• bonding a second semiconductor substrate to a third semiconductor substrate;
• forming a movable mass in the second semiconductor substrate;
• after the second semiconductor substrate and the third semiconductor substrate are bonded together, bonding both the second semiconductor substrate and the third semiconductor substrate to the first semiconductor substrate;
• and
• forming a lower bond ring over the ILD structure and laterally surrounding the sensing electrode;
• wherein forming the lower bond ring and the sensing electrode comprises:
• depositing a conductive layer over the ILD structure;
• and
• removing portions of the conductive layer, thereby leaving a first portion of the conductive layer over the ILD structure as the lower bond ring and leaving a second portion of the conductive layer over the ILD structure as the sensing electrode.