Limits...
Electrothermally-Actuated Micromirrors with Bimorph Actuators--Bending-Type and Torsion-Type.

Tsai CH, Tsai CW, Chang HT, Liu SH, Tsai JC - Sensors (Basel) (2015)

Bottom Line: A silicon-on-insulator MEMS process has been employed for the fabrication of these micromirrors.Electrothermal actuation has achieved a large angular movement in the micromirrors.Application of an external electric current 0.04 A to the bending-type, restricted-torsion-type, and free-torsion-type mirrors achieved rotation angles of 1.69°, 3.28°, and 3.64°, respectively.

View Article: PubMed Central - PubMed

Affiliation: Graduate Institute of Photonics and Optoelectronics and the Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan. d98941019@ntu.edu.tw.

ABSTRACT
Three different electrothermally-actuated MEMS micromirrors with Cr/Au-Si bimorph actuators are proposed. The devices are fabricated with the SOIMUMPs process developed by MEMSCAP, Inc. (Durham, NC, USA). A silicon-on-insulator MEMS process has been employed for the fabrication of these micromirrors. Electrothermal actuation has achieved a large angular movement in the micromirrors. Application of an external electric current 0.04 A to the bending-type, restricted-torsion-type, and free-torsion-type mirrors achieved rotation angles of 1.69°, 3.28°, and 3.64°, respectively.

No MeSH data available.


Photos of the three different electrothermally-actuated MEMS mirrors: (a) bending-type, (b) restricted-torsion-type, and (c) free-torsion-type.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4507607&req=5

sensors-15-14745-f002: Photos of the three different electrothermally-actuated MEMS mirrors: (a) bending-type, (b) restricted-torsion-type, and (c) free-torsion-type.

Mentions: Figures 2a–c are optical microscope images of the bending-type mirror, restricted-torsion-type mirror, and free-torsion-type mirror, respectively. Figure 3 is a schematic drawing of the device from a cross-sectional view along the A–A’ shown in Figure 2c. The structure details are depicted and the materials used are shown. These mirrors are actuated by sending a current mainly through the Cr/Au top layer. The temperature of the bimorph actuator is then substantially increased by Joule heating. The Cr/Au top layer has a higher effective CTE compared to Si bottom layer, causing the top layer expands differently from the bottom layer. This further causes the mirror to tilt away from its initial posture.


Electrothermally-Actuated Micromirrors with Bimorph Actuators--Bending-Type and Torsion-Type.

Tsai CH, Tsai CW, Chang HT, Liu SH, Tsai JC - Sensors (Basel) (2015)

Photos of the three different electrothermally-actuated MEMS mirrors: (a) bending-type, (b) restricted-torsion-type, and (c) free-torsion-type.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4507607&req=5

sensors-15-14745-f002: Photos of the three different electrothermally-actuated MEMS mirrors: (a) bending-type, (b) restricted-torsion-type, and (c) free-torsion-type.
Mentions: Figures 2a–c are optical microscope images of the bending-type mirror, restricted-torsion-type mirror, and free-torsion-type mirror, respectively. Figure 3 is a schematic drawing of the device from a cross-sectional view along the A–A’ shown in Figure 2c. The structure details are depicted and the materials used are shown. These mirrors are actuated by sending a current mainly through the Cr/Au top layer. The temperature of the bimorph actuator is then substantially increased by Joule heating. The Cr/Au top layer has a higher effective CTE compared to Si bottom layer, causing the top layer expands differently from the bottom layer. This further causes the mirror to tilt away from its initial posture.

Bottom Line: A silicon-on-insulator MEMS process has been employed for the fabrication of these micromirrors.Electrothermal actuation has achieved a large angular movement in the micromirrors.Application of an external electric current 0.04 A to the bending-type, restricted-torsion-type, and free-torsion-type mirrors achieved rotation angles of 1.69°, 3.28°, and 3.64°, respectively.

View Article: PubMed Central - PubMed

Affiliation: Graduate Institute of Photonics and Optoelectronics and the Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan. d98941019@ntu.edu.tw.

ABSTRACT
Three different electrothermally-actuated MEMS micromirrors with Cr/Au-Si bimorph actuators are proposed. The devices are fabricated with the SOIMUMPs process developed by MEMSCAP, Inc. (Durham, NC, USA). A silicon-on-insulator MEMS process has been employed for the fabrication of these micromirrors. Electrothermal actuation has achieved a large angular movement in the micromirrors. Application of an external electric current 0.04 A to the bending-type, restricted-torsion-type, and free-torsion-type mirrors achieved rotation angles of 1.69°, 3.28°, and 3.64°, respectively.

No MeSH data available.