Academic
Publications
Tolerance analysis for comb-drive actuator using DRIE fabrication

Tolerance analysis for comb-drive actuator using DRIE fabrication,10.1016/j.sna.2005.08.002,Sensors and Actuators A-physical,J. Li,A. Q. Liu,Q. X. Zha

Tolerance analysis for comb-drive actuator using DRIE fabrication   (Citations: 9)
BibTex | RIS | RefWorks Download
Deep reactive ion etching (DRIE) process is specially invented for bulk micromachining fabrication with the objective of realizing high aspect ratio microstructures. However, various tolerances, such as slanted etched profile, uneven deep beams and undercut, cannot be avoided during the fabrication process. In this paper, the origins of various fabrication tolerances together with its effects on the performances of lateral comb-drive actuator, in terms of electrostatic force, mechanical stiffness, stability and displacement, are discussed. It shows that comb finger with positive slope generates larger electrostatic force. The mechanical stiffness along lateral direction increases when the folded beam slants negatively. The displacement is 4.832 times larger if the comb finger and folded beam are tapered to +1° and −1°, respectively. The uneven deep fingers generate an abrupt force and displacement when the motion distance reaches the initial overlap length. The undercut reduces both the driving force and the mechanical stiffness of the lateral comb-drive actuator. The fabricated comb-drive actuator, with comb finger of +1° profile and 0.025μm undercut, and folded beam of −1° slope and 0.075μm undercut, is measured and compared with the models where both show consistent results. These analytical results can be used to compensate the fabrication tolerances at design stage and allow the actuators to provide more predictable performance.
Journal: Sensors and Actuators A-physical - SENSOR ACTUATOR A-PHYS , vol. 125, no. 2, pp. 494-503, 2006
Cumulative Annual
View Publication
The following links allow you to view full publications. These links are maintained by other sources not affiliated with Microsoft Academic Search.
    • ...Based on the theoretical study of the injection-locked laser chip, the MEMS ILL device is designed and fabricated using SOI wafers and DRIE process [12-13]...

    H. Caiet al. Characteristics of micromachined injection locking lasers

    • ...However, the position of the virtual pivot is determined by the combination of several parameters, so that it is sensitive to the condition changes such as fabrication error, temperature change, and residual stress [10], [21], [22]...
    • ...This is because of the presence of undercut (in the width direction) and notching effect (in the depth direction) in the deep reactive ion etching process, both are dependent on the trench width/shape surrounding the beam [21], [22]...
    • ...This is to avoid the stiction problem, which happens easily due to the capillary forces that occur during the rinsing and drying of wet release [21], [22], [28], [29]...
    • ...The details of the process can be found in [21], [22]...
    • ...Due to the dry etching phenomena in the process such as microloading effect and undercut, the fabricated structures may have different width and depth dependent on the surrounding trench sizes [21], [22], [28]–[30]...
    • ...As to the maximum amount of shifts tolerated by the 4.7 , it needs further study on side stability of the rotary comb drives [13], which is similar to the side stability of translational comb drive [21] but is out of the scope of this paper...

    X. M. Zhanget al. A Real Pivot Structure for MEMS Tunable Lasers

    • ...However, to account for nonideal etching characteristics of DRIE such as over etching and slanted sidewalls [34] as well as to obtain better fitting with the experimental results, a reduced spring constant (kx = 20.54 N/m corresponding to w ≈ 5.9 µm) was used for the calculations in Fig. 3...

    Kyoungsik Yuet al. Tunable Optical Bandpass Filter With Variable-Aperture MEMS Reflector

Sort by: