Method for an optical switch on a substrate

A method comprising:

• providing a glass substrate;
• providing four suspension arms each comprising an internal stress gradient polysilicon layer, each said suspension arm having a first end and a second end, said first end being attached to said substrate;
• providing a polysilicon area having a reflective surface layer, said polysilicon area being attached to said second end of each of said four suspension arms;
• and
• providing four electrodes arranged on said glass substrate adjacent to said four metal suspension arms, respectively, to create an electric field for producing deflective movement of said polysilicon area having said reflective surface layer.

A method performed on a substrate, comprising:

• producing an array of at least one mirror structure at a surface of the substrate, each mirror structure including:
• two or more suspension arms, each arm having an internal stress gradient, each arm further having an end attached to the substrate's surface, the arm extending from the substrate's surface to an attachment point;
• a mirror attached to the attachment points of the suspension arms, the mirror including a polysilicon area and a reflective area on the polysilicon area, the polysilicon area including parts of first and second polysilicon layers, the first and second polysilicon layers having internal stress gradients acting in different directions;
• and
• electrodes operable to deflect the suspension arms, the electrodes being operable together to tilt the mirror by deflecting the suspension arms.

A method performed on a substrate structure, comprising:

• producing an array of at least one optical device on the substrate structure each optical device including:
• each arm two or more suspension arms, each including part of a polysilicon layer each arm further extending from a first end attached to the substrate structure to second end not attached to the substrate structure;
• the polysilicon layer having a internal stress gradient that moves the arm away from the substrate structure;
• an optical element supported on the second ends of the suspension arms;
• and
• for each suspension arm, an electrode that responds to an actuation signal by attracting the suspension arm toward the substrate structure.

A method performed on a substrate structure, comprising:

• producing an array of optical devices on the substrate structure, each optical device including:
• two or more suspension arms, each arm further having a length extending from a first end attached to the substrate structure to a second end that is not attached to the substrate structure;
• each arm being movable between a first position in which the arm's length has an initial separation from the substrate structure and a second position in which the arm's length is drawn toward the substrate structure, decreasing at separation;
• each arm having an internal stress gradient polysilicon layer moving the arm's length toward the first position;
• an optical element supported on the second ends of the suspension arms;
• and
• for each suspension arm, an electrode under the suspension arm, the electrode responding to an actuation signal by deflecting the suspension arm from its first position toward its second position;
• the electrodes responding individually to the actuation signals to tilt the optical element around two non-collinear axes.

A method performed on a glass substrate structure, comprising:

• producing an array of mirror structures on the substrate structure, each mirror structure including:
• two or more suspension arms, each arm having a length extending from a first end attached to the substrate structure to a second end that is not attached to the substrate structure;
• each arm being movable between a first position in which the arm's length has an initial separation from the substrate structure and a second position in which the arm's length is drawn toward the substrate structure, decreasing separation;
• each arm having an internal stress gradient polysilicon layer moving the arm's length toward the first position;
• a mirror supported on the second ends of the suspension arms, the mirror including a polysilicon area and a reflective surface layer;
• and
• for each suspension arm, an electrode under the suspension arm, the electrode responding to an actuation signal by creating an electric field that deflects the suspension arm from its first position toward its second position by beginning to decrease separation at the arm's first end and proceeding to decrease separation along the length of the arm toward the arm's second end;
• the electrodes responding individually to the actuation signals to tilt the mirror around two non-collinear axes;
• the act of producing the array of mirror structures comprising:
• producing first, second, and third patterned layers over the substrate structure:
• the first patterned layer including the electrodes of the mirror structures;
• the second patterned layer being a polysilicon layer over the first patterned layer and including the internal stress gradient polysilicon layers of the suspension arms and the polysilicon areas of the mirrors:
• the third patterned layer being over the second patterned layer and including the reflective surface layers of the mirrors;
• and
• releasing the mirror structures to allow the internal stress gradient polysilicon layer of each suspension arm to move the suspension arm toward its first position.