Design and Characterization of Single-Layer Step-Bridge Structure for Out-of-Plane Thermal Actuator

J. Micromech. Microeng.

Gupta

2013

Realizing out-of-plane actuation in micro-electro-mechanical systems (MEMS) is still a challenging task. In this paper, the design, fabrication methods and experimental results for a MEMS-based out-of-plane motion stage are presented based on bulk micromachining technologies. This stage is electrothermally actuated for out-of-plane motion by incorporating beams with step features. The fabricated motion stage has demonstrated displacements of 85 μm with 0.4 μm (mA) −1 rates and generated up to 11.8 mN forces with stiffness of 138.8 N m −1. These properties obtained from the presented stage are comparable to those for in-plane motion stages, therefore making this out-of-plane stage useful when used in combination with in-plane motion stages.

Section: Introductionmentioning

confidence: 99%

Creating large out-of-plane displacement electrothermal motion stage by incorporating beams with step features

J. Micromech. Microeng.

Gupta

2013

“…This stage is composed of an actuator, an oscillating plate, and eight folded springs and each component is analyzed in the following section. An electrothermal actuator is adapted as an actuator and designed for its reliable operation in dusty environments [14], [15]. A capacitive displacement sensor is attached at the end of the oscillating plate to monitor its behavior and the large square plate of micro-scale level is used to hold the paste tested.…”

Section: Introductionmentioning

confidence: 99%

Design of a 1 DOF MEMS motion stage for a parallel plane geometry rheometer

Ferraris

et al. 2016

ELS

Rotational rheometers are used to measure paste properties, but the test would take too long to be useful for quality control (QC) on the job site. In this paper, a new type of rheometer is proposed based on a one degree of freedom (DOF) micro-electro-mechanical systems (MEMS)-based motion stage. Preliminary data will be presented to show the capability of the system to measure the viscoelastic properties of a paste. The parallel plate geometry rheometer consists of two plates, which move relative to each other to apply a strain to the material to be tested. From the stress measured and the strain applied, the rheological characteristics of the material can be calculated. The new device consists of an electrothermal actuator and a motion plate. For the rheological measurements, the device is designed to generate the shear stress up to 60 Pa and maintain its stiffness to less than 44 N/m. With these features, the device uses a square plate of 1.5 mm x 1.5 mm to provide enough area for a few micro-liter level volumes. The motion of the square plate is monitored by a capacitive sensor at the end of the oscillating plate which has a resolution of 1.06 μm. When a reference cementitious paste, Standard Reference Material (SRM)-2492, is placed between the oscillating plate of the presented motion stage and a fixed plate, the reduction in the displacement of the oscillating plate is monitored showing that the presented motion stage is reasonably designed to detect the response of the reference cementitious paste.

“…But the connection of parts between multi-layers tends to be under significant shear stress during operation, so those tend to fail faster than other parts and reduce the total life-time of the system. To avoid this kind of a problem, a single layer electrothermal actuator was introduced [10]. The single layer actuator is made of a single layer with different height like bridges or steps [9,10], so there is no stress concentration between layers.…”

Section: Introductionmentioning

confidence: 99%

“…To avoid this kind of a problem, a single layer electrothermal actuator was introduced [10]. The single layer actuator is made of a single layer with different height like bridges or steps [9,10], so there is no stress concentration between layers. With the single layer, the life-time of the proposed actuator can be protected [10].…”

Section: Introductionmentioning

confidence: 99%

“…The single layer actuator is made of a single layer with different height like bridges or steps [9,10], so there is no stress concentration between layers. With the single layer, the life-time of the proposed actuator can be protected [10]. But this step-bridge shape needs additional processes to build the desired step shapes on the single layer.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Design, fabrication and characterization of a single-layer out-of-plane electrothermal actuator for a MEMS XYZ stage

Proceedings of the Workshop on Performance Metrics for Intelligent Systems

Gupta

2012

This paper presents the design, fabrication and characterization of a single-layer out-of-plane electrothermal actuator based on MEMS (Micro-Electro-Mechanical System). The proposed electrothermal actuator is designed to generate motions along the out-of-plane or normal to a wafer by a Joule heating when the current flows through the actuator. This out-of-plane electrothermal actuator is based on a single layer of a SOI (Silicon on Insulator) wafer and two notches near the middle of the actuator beams. Due to these notches, the thermal expansion of the beams in the actuator generates an eccentric loading, which converts into the bending of the beams. This bending of the beam finally generates the out-of-plane motion at the middle of the beam. This behavior is described by the prepared analytic equations and compared by the results from FEM (Finite element Model) analysis. With fabricated samples, a 30 m displacement is measured along out-of-plane at 5 V driving voltage. The 1st mode of the resonant frequency for the out-of-plane motion is expected to occur at 74.9 kHz from FEA. The proposed actuator is based on the standard SOI-MUMPs (SOI-Multi User Manufacturing Process) , so it has good integration capability with other system employing same fabrication techniques. To test its integration capability, a MEMS XYZ stage is fabricated by embedding the proposed out-of-plane electrothermal actuator onto an existing MEMS XY stage. The range of motion of the fabricated XYZ stage is measured about 35 m x 35 m x 30 m along X, Y and Z axes without any changes on its fabrication process.