Planar cavity MEMS and related structures, methods of manufacture and design structures

A method of forming at least one Micro-Electro-Mechanical System (MEMS), comprising:

• forming a lower sacrificial material used to form a lower cavity;
• forming a cavity via connecting the lower cavity to an upper cavity, the cavity via being formed with a top view profile of rounded or chamfered edges;
• forming an upper sacrificial material within and above the cavity via, which has a resultant surface based on the profile of the cavity via,
• wherein the upper cavity is formed with a lid that is devoid of structures that would interfere with a MEMS beam, comprising:
• depositing a lid material on the resultant surface of the upper sacrificial material;
• venting the upper sacrificial material to form the upper cavity such the lid material forms the lid which conforms with the resultant surface of the upper sacrificial material;
• depositing the upper sacrificial material using a non-regressive silicon deposition process to form a profile comprising tapered side walls on an upper surface;
• depositing the lid material over the upper sacrificial material and within a depression formed from the tapered side walls;
• patterning at least one vent hole in the lid;
• and
• venting or stripping the upper sacrificial material through the at least one opening such that the lid includes the profile of the sacrificial material,
• wherein the non-regressive silicon deposition process comprises a conformal silicon deposition process including performing multiple plasma vapor deposition (PVD) silicon deposition and rf biased wafer etchback steps, wherein the non-regressive deposition process eliminates a regressive overhang structure of the lid material.

A method of forming at least one Micro-Electro-Mechanical System (MEMS), comprising:

• forming a plurality of discrete wires on a substrate in a lower cavity initially filled with a first layer of sacrificial material;
• forming a MEMS beam on the first layer of sacrificial material;
• depositing a second layer of sacrificial material within a cavity via extending to the lower cavity, the deposition of the second layer of sacrificial material being a non-regressive silicon deposition process comprising a conformal silicon deposition process with multiple plasma vapor deposition (PVD) silicon deposition and rf biased wafer etchback steps to achieve a non-regressive opening above the cavity via;
• forming a lid material on the second layer of sacrificial material;
• and
• venting the second layer of sacrificial material and the sacrificial material to form the lower cavity and an upper cavity which comprises a lid formed from the lid material, the lid being devoid of structures that would interfere with the MEMS beam.

A method of forming a Micro-Electro-Mechanical System (MEMS) structure, comprising:

• forming a MEMS cavity;
• and
• forming a MEMS beam with sufficient clearance from a lid structure such that the MEMS beam will not be riveted when released,
• wherein the forming the MEMS beam comprises:
• depositing sacrificial material using a non-regressive silicon deposition process to form a profile comprising tapered side walls on an upper surface;
• and
• venting or stripping the sacrificial material through at least one opening,
• wherein the non-regressive silicon deposition process comprises a conformal silicon deposition process including performing multiple plasma vapor deposition (PVD) silicon deposition and rf biased wafer etchback steps, wherein the non-regressive deposition process eliminates a regressive overhang structure of the lid structure.

A method in a computer-aided design system for generating a functional design model of a MEMS, the method comprising:

• generating a functional representation of a cavity via with a top view profile of rounded or chamfered edges, which connects a lower cavity to an upper cavity;
• generating a functional representation of a lower sacrificial material within the lower cavity, wherein the cavity via with the top view profile of the rounded or the chamfered edges is generated prior to a venting of the lower sacrificial material from the lower cavity;
• generating a functional representation of an upper sacrificial material within and above the cavity via, which has a resultant surface based on the profile of the electrical vias and the cavity via;
• and
• generating a functional representation of the upper cavity having a lid that is devoid of structures that would interfere with a MEMS beam, comprising a lid material on the resultant surface of the upper sacrificial material, and a venting of the upper sacrificial material within and above the cavity via such that the lid structure forms a lid that conforms with the resultant surface of the upper sacrificial material,
• wherein:
• the functional representation of the upper sacrificial material comprises a profile comprising tapered side walls on an upper surface, which is formed using a non-regressive silicon deposition process;
• the non-regressive silicon deposition process comprises a conformal silicon deposition process including performing multiple plasma vapor deposition (PVD) silicon deposition and rf biased wafer etchback steps;
• the non-regressive deposition process eliminates a regressive overhang structure of the lid material;
• and
• the functional representations are generated using a processor of the computer-aided design system.