Mems reflectors having tail portions that extend inside a recess and head portions that extend outside the recess and methods of forming same

A MEMS reflector in an Optical Cross Connect (OXC) switch comprising:

• a substrate;
• a recess in the substrate having a side wall and a floor;
• a moveable reflector having a tail portion extending on the substrate beyond a first portion of the side wall opposite the recess floor configured to rotate into the recess and a head portion extending beyond the side wall on the substrate outside the recess;
• a hinge coupled to the moveable reflector and to the side wall to define an axis about which the moveable reflector is configured to rotate in a first direction into the recess to move the tail towards the side wall and to rotate in a second direction out of the recess to move the tail away from the side wall;
• and
• a latch member on the substrate extending opposite the floor beyond a second portion of the side wall opposite the first portion of the side wall to contact the tail, wherein the latch member holds the head away from the substrate to define a wedge shaped gap between the head and the substrate opposite the head.

A MEMS Angle-To-Offset (ATO) optical switch comprising:

• a relay lens having a central optical axis;
• a plurality of optical inputs, located on a first side of the central optical axis, that provide input optical radiation along an input optical path to the relay lens;
• a plurality of optical outputs, located on a second side of the central optical axis opposite the first side, that receive output optical radiation along an output optical path from the relay lens;
• an ATO lens having a concave reflecting surface facing the relay lens and centered on the central optical axis;
• a first array of MEMS reflectors facing the concave surface of the ATO lens and positioned on the first side of the optical axis between the relay lens and the ATO lens, wherein the MEMS reflectors of the first array are angled towards the optical axis;
• a second array of MEMS reflectors facing the concave surface of the ATO lens and positioned on the second side of the optical axis between the relay lens and the ATO lens, wherein the MEMS reflectors of the second array are angled towards the optical axis;
• and
• wherein optical radiation is conducted from the inputs through the relay lens to the ATO lens and reflected to the second array of MEMS reflectors which reflect the optical radiation across the central optical axis to the first array of MEMS reflectors via the ATO lens which reflect the optical radiation parallel to the central optical axis back to the ATO lens which reflects the optical radiation to the plurality of outputs through the relays lens.

A Microelectromechanical System (MEMS) structure comprising:

• a substrate;
• a recess in the substrate having a side wall;
• and
• a moveable reflector on the substrate that pivots on the side wall and is cantilevered thereon to define a neutral position that avoids contact with the substrate.

A method of forming a Microelectromechanical System (MEMS) structure comprising:

• depositing a nitride layer on a substrate;
• patterning the nitride layer to form a hinge and a latch member spaced apart on the substrate;
• forming a moveable reflector on the hinge and on the a portion of the latch member closest to the hinge using electroplating;
• releasing the moveable reflector from substrate;
• and
• etching the substrate to form a recess beneath the hinge and the latch member.