Parallel-kinematics XYZ MEMS part 1: Kinematics and design for fabrication

Abstract

Micro-and nanopositioning systems are widely used in the field of nanotechnology for probing, imaging, and increasingly for processing. This two-part set of papers presents a MEMS-scale parallel-kinematics mechanism, designed to achieve pure spatial (X, Y and Z) translation. With three independent kinematic chains connecting the end-effector to the base, a fully functional mechanism with axis actuation and displacement sensing is realized in a double device layer ("oreo") SOI wafer using only conventional, microfabrication processes. This paper, the first in a two paper set, presents the mechanism, specially designed for scalable microfabrication. It analyzes its kinematics and dynamics, and characterizes its workspace. Part II of this set of papers describes the detailed design, fabrication, characterization and control of the devices.

Parallel-kinematics XYZ MEMS part 2: Fabrication and experimental characterization

“…The designed device is expected to be a general-purpose, MEMS-scale, spatial positioning platform that can be adapted to several possible applications. Motivated by applications in nano-indentation, confocal microscopy, scanned probe microscopy, the design objectives are to realize an in-substrate, low-profile stage based on the kinematic scheme developed in [1], and actuated by electrostatic drives. The stage is designed to have workspace capable of embedding a cube of dimension 20μm x 20μm x 20μm and is to be actuated by electrostatic drives with a maximum voltage of less than 150V.…”

“…n the companion paper [1], we have discussed the kinematics, dynamics and design approach to a parallel-kinematics, MEMSscale, spatial translation stage concept (referred to as a PK-XYZ-MEMS stage), realizable on a double device layer silicon-oninsulator (SOI) substrate. We have shown that the forward position kinematics problem is reduced to a sixth-order polynomial equation, and that the inverse position kinematics problem admits closed-form solution.…”

“…The purpose of this paper is to discuss the physical realization of a PK-XYZ-MEMS stage, explain the fabrication process, experimentally characterize its workspace, verify its mobility, and validate its static and dynamic performance. The companion paper [1] also reported on the design methodology of a PK-XYZ-MEMS stage and, while elucidating the design methodology and verifying the kinematic and dynamic equations, produced a detailed design of a MEMS stage with previously unrealized mechanical specifications. The reader may find it useful to refer back to [1] for details of the formulae and procedures used.…”

“…The companion paper [1] also reported on the design methodology of a PK-XYZ-MEMS stage and, while elucidating the design methodology and verifying the kinematic and dynamic equations, produced a detailed design of a MEMS stage with previously unrealized mechanical specifications. The reader may find it useful to refer back to [1] for details of the formulae and procedures used. Section II of this paper reviews the design objectives, motivation, and design rationale and summarizes aspects of the design that are important from the point of view of fabrication.…”

A Large Range of Motion 3D MEMS Scanner With Five Degrees of Freedom

“…One of the most complete electrostatic actuators has been demonstrated by Correa et al [22] and Koo et al [20] in their partner articles. Their device is capable of moving in a 20 µm cube using a silicon-on-insulator (SOI) process and closed loop control.…”